Living bioreactor compositions and methods of use

Abstract

The present disclosure provides compositions comprising a structure for use as a therapeutic cell niche. Additionally, provided herein are methods for using such compositions, e.g., for use in cell therapy in a subject in need thereof.

Description

[0001] LIVING BIOREACTOR COMPOSITIONSAND METHODS OF USE

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of U.S. Provisional Application 63 / 598,496, filed on November 13, 2023, the entirety of which is incorporated by reference herein.

[0004] SEQUENCE LISTING

[0005] The application contains a Sequence Listing, which is submitted herewith in XML format, and is hereby incorporated by reference in its entirety. The XML copy, created on November 13, 2023, is named 50222-713 601. xml and is 721,232 bytes in size.

[0006] BACKGROUND

[0007] The cell microenvironment plays a significant role in cell therapy. For example, the bone marrow can serve as a niche that supports cell viability.

[0008] SUMMARY

[0009] In one aspect, the present disclosure provides compositions for supporting cell therapies. Compositions include ceramic scaffolds, formulations for preparing scaffolds (e.g., ink formulations for generating a 3D printed scaffold), and therapeutic agents. Therapeutic agents include those that promote bone growth and the production of bone marrow. Compositions herein may be combined (e.g., a scaffold and a therapeutic agent), seeded with cells to generate devices for use in tissue replacement and grafting, and / or utilized to support cell therapy in vivo. As such, compositions herein may be referred to as living bioreactors, or therapeutic living bioreactors. For some compositions, therapeutic agents may be tethered to the scaffold via a targeting moiety that interacts with a scaffold component, such as a ceramic material. Advantages of the compositions and methods described herein may include production of bone marrow and providing a living bioreactor to support cell therapy.

[0010] Provided herein is a method of treating a subject, the method comprising delivering to the subject a device comprising a first three-dimensional structure and a first therapeutic agent tethered to the three-dimensional structure via a first targeting moiety; wherein the three- dimensional structure comprises calcium phosphate and optionally a polymer, the calcium phosphate is present in the three-dimensional structure at 50% to 100%by weight, and the polymer is present in the three-dimensional structure at 0% to 50% by weight; wherein the method of treating (i) comprises a cell therapy, a tissue replacement therapy, or a tissue graft and / or (ii) results in bone marrow formation in the subject, production of lymphocytes in the subject, or T cell formation in the subject, or a combination of two or more thereof; and wherein the first therapeutic agent comprises bone morphogenetic protein 2 (BMP -2), epidermal growth factor (EGF), platelet derived growth factor (PDGF), insulin like growth factor (IGF-1), fibroblast growth factor (FGF), fibroblast growth factor 2 (FGF2), fibroblast growth factor 18 (FGF18), transforming growth factor alpha (TGF-a), transforming growth factor beta (TGF-P), transforming growth factor beta 1 (TGF-P 1), transforming growth factor beta 3 (TGF-P3), osteogenic protein 1 (OP-1), osteogenic protein 2 (OP -2), osteogenic protein 3 (OP-3), bone morphogenetic protein 3 (BMP-3), bone morphogenetic protein 4 (BMP-4), bone morphogenetic protein 5 (BMP-5), bone morphogenetic protein 6 (BMP-6), bone morphogenetic protein 7 (BMP- 7), bone morphogenetic protein (BMP-9), bone morphogenetic protein 10 (BMP-10), bone morphogenetic protein 11 (BMP-11), bone morphogenetic protein 12 (BMP-12), bone morphogenetic protein 13 (BMP-13), bone morphogenetic protein 15 (BMP-15), delta-like ligand-4 (DLL4), dentin phosphoprotein (DPP), vegetal related growth factor (VGR), growth differentiation factor 1 (GDF-1), growth differentiation factor 3 (GDF-3), growth differentiation factor 5 (GDF-5), growth differentiation factor 6 (GDF-6), growth differentiation factor 7 (GDF- 7), growth differentiation factor 8 (GDF8), growth differentiation factor 11 (GDF11), growth differentiation factor 15 (GDF15), vascular endothelial growth factor (VEGF), hyaluronic acid binding protein (HABP), collagen binding protein (CBP), fibroblast growth factor 18 (FGF-18), keratinocyte growth factor (KGF), tumor necrosis factor alpha (TNFa), tumor necrosis factor (TNF)- related apoptosis inducing ligand (TRAIL), wnt family member 1 (WNT1), wnt family member2 (WNT2), wntfamily member 2B (WNT2B), wntfamily member 3 (WNT3), wntfamily member 3 A (WNT3 A), wnt family member 4 (WNT4), wnt family member 5 A (WNT5 A), wnt f amily memb er 5 B (WNT 5 B), wnt f amily m emb er 6 (WNT6), wnt f amily memb er 7 A (WNT7 A), wnt family member 7B (WNT7B), wnt family member 8A (WNT8A), wnt family member 8B (WNT8B), wnt family member 9A (WNT9A), wnt family member 9B (WNT9B), wnt family member 10A (WNT10 A), wntfamily member 1 OB (WNT 1 OB), wntfamily member 11 (WNT11), or wnt family member 16 (WNT16), or a mature peptide or functional portion thereof.

[0011] In some embodiments, the device comprises a second therapeutic agent, wherein the second therapeutic agent is BMP-2, and the first therapeutic agent is the epidermal growth factor (EGF), platelet derived growth factor (PDGF), insulin like growth factor (IGF-1), fibroblast growth factor (FGF), fibroblast growth factor 2 (FGF2), fibroblast growth factor 18 (FGF18), transforming growth factor alpha (TGF-a), transforming growth factor beta (TGF-P), transforming growth factor beta 1 (TGF-P 1), transforming growth factor beta 3 (TGF-P3), osteogenic protein 1 (OP-1), osteogenic protein 2 (OP -2), osteogenic protein 3 (OP-3), bone morphogenetic protein 3 (BMP-3), bone morphogenetic protein 4 (BMP-4), bone morphogenetic protein 5 (BMP-5), bone morphogenetic protein 6 (BMP-6), bone morphogenetic protein 7 (BMP- 7), bone morphogenetic protein (BMP-9), bone morphogenetic protein 10 (BMP-10), bone morphogenetic protein 11 (BMP-11), bone morphogenetic protein 12 (BMP-12), bone morphogenetic protein 13 (BMP-13), bone morphogenetic protein 15 (BMP-15), delta-like ligand-4 (DLL4), dentin phosphoprotein (DPP), vegetal related growth factor (VGR), growth differentiation factor 1 (GDF-1), growth differentiation factor 3 (GDF-3), growth differentiation factor 5 (GDF-5), growth differentiation factor 6 (GDF-6), growth differentiation factor 7 (GDF- 7), growth differentiation factor 8 (GDF8), growth differentiation factor 11 (GDF11), growth differentiation factor 15 (GDF15), vascular endothelial growth factor (VEGF), hyaluronic acid binding protein (HABP), collagen binding protein (CBP), fibroblast growth factor 18 (FGF-18), keratinocyte growth factor (KGF), tumor necrosis factor alpha (TNFa), tumor necrosis factor (TNF)- related apoptosis inducing ligand (TRAIL), wnt family member 1 (WNT1), wnt family member2 (WNT2), wntfamily member 2B (WNT2B), wntfamily member 3 (WNT3), wntfamily member 3 A (WNT3 A), wnt family member 4 (WNT4), wnt family member 5 A (WNT5 A), wnt f amily memb er 5 B (WNT 5 B), wnt f amily memb er 6 (WNT6), wnt f amily memb er 7 A (WNT7 A), wnt family member 7B (WNT7B), wnt family member 8A (WNT8A), wnt family member 8B (WNT8B), wnt family member 9A (WNT9A), wnt family member 9B (WNT9B), wnt family member 10A (WNT10A), wntfamily member 1 OB (WNT 1 OB), wntfamily member 11 (WNT11), or wnt family member 16 (WNT16), or mature peptide or functional portion thereof. In some embodiments, the second therapeutic agent is tethered to the three-dimensional structure via a second targeting moiety.

[0012] The three-dimensional structure may be in a granular form, a porous form, a powder, a putty, a paste, or fiber form. The three-dimensional structure may be printed using additive manufacturing.

[0013] In some embodiments, the calcium phosphate is present in the three-dimensional structure at 50% to 70% by weight, and the polymer is present in the three-dimensional structure at 30% to 50% by weight. In some embodiments, the polymer comprises polycaprolactone, caprolactone / glycolide copolymer, poly(D,L-lactide-co-glycolide) copolymer, poly(lactic-co- glycolic acid) (PLGA), or dioxanone / L-lactide copolymer, or a combination thereof. In some embodiments, the polymer comprises caprolactone / glycolide copolymer. In some embodiments, the three-dimensional structure has a density of 1 g / cm3to 3 g / cm3. In some embodiments, the three-dimensional structure has an open porosity of 15%to 45%. In some embodiments, the three- dimensional structure comprises a fiber having a diameter of 325 pm and 475 pm. In some embodiments, the three-dimensional structure has a plurality of micropores. In some embodiments, the micropores have an average pore size of about 1 micron to about 500 microns, or about 50 microns to about 250 microns, or about 150 microns in diameter. In some embodiments, the three-dimensional structure has a strut diameter of about 300 micrometers to about 600 micrometers.

[0014] The method may comprise delivering to the subject the cell therapy. The method may comprise delivering to the subject a tissue graft. The method may comprise delivering to the subject insulin, a GLP1 agonist, antibody, and / or recombinant biologic.

[0015] The method may comprise deliveringto the subject a second three-dimensional structure. In some embodiments, the second three-dimension structure comprises calcium phosphate and a polymer. In some embodiments, calcium phosphate is present in the second three-dimensional structure at 50% to 70% by weight of the second three-dimensional structure, and the polymer is present in the second three-dimensional structure at 30% to 50% by weight of the second three- dimensional structure. In some embodiments, the polymer comprises polycaprolactone, caprolactone / glycolide copolymer, poly(D,L-lactide-co-glycolide) copolymer, poly(lactic-co- gly colic acid) (PLGA), or dioxanone / L-lactide copolymer, or a combination thereof. The second three-dimensional structure may be in a granular form, a porous form, a powder, a putty, a paste, or fiber form.

[0016] The details of one or more embodiments of the disclosure are setforthinthe accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims.

[0017] BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG. 1A is an example composition herein that functions as a living bioreactor or niche for cell therapy. FIG. IB shows bone marrow and new bone formation after implant of a living bioreactor into a subject. FIG. 1C shows the formation of osteoblasts, fibrocartilage, and fibrous tissue observable after 8 weeks of implantation. FIG. ID shows stable bone marrow formation was observable after 26 weeks.

[0019] FIGS. 2A-2C areimagesfrom scanningelectronmicroscopy(SEMimages) of an example 3D printed object made with ink formulation #1 as outlinedin Example 2. FIG. 2 A and FIG.2C are SEM images of the surface of the object at increasing magnifications. FIG. 2B is an SEM image of the side of the object. FIGS. 3A-3C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation #2 as outlinedin Example 2. FIG. 3 A and FIG.3C are SEM images of the surface of the object at increasing magnifications. FIG. 3B is an SEM image of the side of the object.

[0020] FIGS. 4A-4C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation #3 as outlinedin Example 2. FIG. 4 A and FIG.4C are SEM images of the surface of the object at increasing magnifications. FIG. 4B is an SEM image of the side of the object.

[0021] FIGS. 5A-5C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation #4 as outlinedin Example 2. FIG. 5 A and FIG.5C are SEM images of the surface of the object at increasing magnifications. FIG. 5B is an SEM image of the side of the object.

[0022] FIGS. 6A-6C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation #5 as outlinedin Example 2. FIG. 6 A and FIG.6C are SEM images of the surface of the object at increasing magnifications. FIG. 6B is an SEM image of the side of the object.

[0023] FIGS. 7A-7C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation #6 as outlinedin Example 2. FIG. 7 A and FIG.7C are SEM images of the surface of the object at increasing magnifications. FIG. 7B is an SEM image of the side of the object.

[0024] FIGS. 8A-8C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation #7 as outlinedin Example 2. FIG. 8 A and FIG.8C are SEM images of the surface of the object at increasing magnifications. FIG. 8B is an SEM image of the side of the object.

[0025] FIGS. 9A-9C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation #8 as outlinedin Example 2. FIG. 9 A and FIG.9C are SEM images of the surface of the object at increasing magnifications. FIG. 9B is an SEM image of the side of the object.

[0026] FIGS. 10A-10C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation #9 as outlined in Example 2. FIG. 10A and FIG. IOC are SEM images of the surface of the object at increasing magnifications. FIG. 10B is an SEM image of the side of the object.

[0027] FIGS. 11A-10C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation #10 as outlined in Example 2. FIG. 11A and FIG. 11C are SEM images of the surface of the object at increasing magnifications. FIG. 11B is an SEM image of the side of the object.

[0028] FIGS. 12A-12C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation # 11 as outlined in Example 2. FIG. 12A and FIG. 12C are SEM images of the surface of the object at increasing magnifications. FIG. 12B is an SEM image of the side of the object.

[0029] FIGS. 13A-13C are images from scanning electron microscopy (SEM images) of an example 3D printed object made with ink formulation # 12 as outlined in Example 2. FIG. 13A and FIG. 13C are SEM images of the surface of the object at increasing magnifications. FIG. 13B is an SEM image of the side of the object.

[0030] FIG. 14A is a photograph of an example flexible 3 -layer membrane made with ink formulation #16 3Dprinted with a 400 micron nozzle as outlinedin Example 2. FIGS. 14B-14D are images from scanning electron microscopy (SEM images) of the flexible 3 -layer membrane at increasing magnifications.

[0031] FIG. 15A is a photograph of an example gyroid scaffold made with ink formulation #16 3D printed with a 400 micron nozzle as outlinedin Example 2. FIGS. 15B-15D are images from scanning electron microscopy (SEM images) of the gyroid scaffold at increasing magnifications.

[0032] FIG. 16A is a photograph of an example flexible 3 -layer membrane made with ink formulation #18 3D printed with a 400 micron nozzle as outlined in Example 2. FIG. 16B is a photograph of a hollow cylinder made with ink # 183D printed with a 400 micron nozzle as outline in Example 2.

[0033] FIG. 17A is a photograph of an example flexible 3 -layer membrane made with ink formulation #19 3D printed with a 400 micron nozzle as outlined in Example 2. FIG. 17B is a photograph of a hollow cylinder made with ink #193D printed with a 400 micron nozzle as outline in Example 2.

[0034] FIG. 18A are microscope images of L929 mouse fibroblasts following an in vitro cytotoxicity assay that was performed to determine cell response, specifically toxic effects, when exposed to extracts from the 3D printed scaffolds. FIG. 18B shows the results of the cytotoxicity assay as determined using the following cytotoxicity scale defined in ISO 10993 -5:2009 standard.

[0035] FIG. 19A shows a composition herein comprising a structure (e.g., 3D printed scaffold) (left) and a therapeutic agent comprising an autograft or allograft material. FIG. 19B shows a composition herein comprising two structures - a 3D printed scaffold, and within the 3D printed scaffold, a structure comprised of fibers (referenced to with an arrow). In this example composition, bound to the structure comprised of fibers is a therapeutic agent, such as a growth factor that is tethered to the fibers via a peptide. FIG. 19C shows a composition comprising a 3D printed scaffold (left) combined with a therapeutic agent, such as a growth factor, that is tethered to the scaffold via a peptide.

[0036] FIG. 20 is a stained histology section showing an implant of the present application harvested at 28 days.

[0037] FIG. 21 is a stained histology section of the implant showing extensive bone marrow genesis.

[0038] FIG. 22 is a stained histology section of the implant showing the presence of red blood cells.

[0039] FIGS. 23A-23B show different orientations of a 3D printed scaffold of the present application.

[0040] FIG. 24 shows an example multilayer bioreactor of the present application comprising a first ceramic structure shell (101 ), a second ceramic structure shell (102), and an internal ceramic structure (103). In an example, the first and third ceramic scaffolds are 3D printed. For instance, the first ceramic structure shell of FIGS. 23A-23B. The second ceramic structure may be in a granular form, a porous form, a powder, a putty, a paste, fiber form, or a coating on the surface of the first and / or third structures.

[0041] DETAILED DESCRIPTION

[0042] Various compositions, such as therapeutic agents, formulations and structures, are provided herein. The structures may be coated with a therapeutic agent, e.g. , a tetherable protein (for example, a growth factor) for a desired therapeutic effect, such as promotion of bone marrow after implantation of the tethered structure. The compositions herein may serve as a living bioreactor to support cell therapy.

[0043] Methods of Treatment

[0044] In one aspect, provided are methods of administering to a subject a composition herein, e.g., a therapeutic agent and / or structure. In some methods, the subject is treated with a device comprising the therapeutic agent and the structure. In some instances, the subject has undergone, is undergoing, or will undergo a cell therapy. In some instances, the composition is a living bioreactor that provides a niche to support the cell therapy . The niche may be highly vascularized. The niche may be a bone marrow microenvironment. In some instances, administration of the composition produces new bone marrow in the subject. Cell therapy methods provided herein include administering to a subject a composition (e.g. , therapeutic agent and / or structure), and a cell therapy. The administration may be sequential or co-administration. The cell therapy may comprise administering to a subject a cell that expresses a therapeutic gene or peptide. The therapeutic peptide may be, e.g., insulin or an antibody. This antibody delivery can be used as an alternative to infusion. It is contemplated that a variety of therapeutics and / or pharmaceuticals can be similarly delivered via therapeutic living bioreactors. Advantages of this administration include precise localization of therapeutics and / or pharmaceuticals.

[0045] In one example, a therapeutic living bioreactor is used to develop an artificial thymus to support the immune system. This artificial thymus is useful for the production of lymphocytes in a subject with e.g., an immune disorder.

[0046] In another example, a therapeutic living bioreactor is used for metabolic cell therapies. One example of a metabolic cell therapy for which a therapeutic livingbioreactor is used is insulin release. This insulin releasing therapeutic living bioreactor is useful in a subject with diabetes.

[0047] Compositions

[0048] In one aspect, provided herein are compositions comprising a structure that may be delivered (e.g., implanted) into a subject. In some embodiments, the compositions comprise a therapeutic agent, such as a growth factor, that optionally is tethered to the structure. The compositions may provide an environment (e.g., niche) suitable for cell therapy. As such, compositions herein may be delivered in combination with, or prior to, a cell therapy. Nonlimiting example compositions are shown in FIGS. 1A and 19A-19C.

[0049] FIG. 1A is an example embodiment of a composition serving as a niche for cells. The composition may comprise a structure described herein. For example, a structure comprising a calcium containing compound, such as calcium phosphate. FIG. 19A is an example composition comprising a structure (e.g., 3D printed scaffold) (left) and a therapeutic agent comprising an autograft or allograft material. FIG. 19B is an example composition comprising two structures - a 3D printed scaffold, and within the 3D printed scaffold (area referenced with an arrow), a structure comprised of fibers. In this example composition, bound to the structure comprised of fibers is a therapeutic agent, such as a growth factor that is tethered to the fibers via a peptide. FIG. 19C is an example composition comprising a 3D printed scaffold (left) combined with a therapeutic agent, such as a growth factor, that is tethered to the scaffold via a peptide. Structures

[0050] In one aspect, provided herein are structures that may be delivered to a subject, for example, in a method described herein. For instance, the structures maybe delivered to the subject to provide a niche for cell therapy. The structures may be part of a device further comprising a therapeutic agent. As anon-limiting example, thetherapeutic agentisbound to the structure. The structure or device may generate bone marrow in the subject.

[0051] In some embodiments, a structure herein comprises a calcium containing compound. Nonlimiting exemplary structure materials include calcium phosphate (e.g. , tricalcium phosphate, beta tricalcium phosphate, alpha tricalcium phosphate), hydroxyapatite, fluorapatite, bone (e.g., demineralized bone), glasses (bioglasses) such as silicates, vanadates, and related ceramic minerals, and chelated divalent metal ions. Specific example structures include, without limitation, Mastergraft strip, VitossFoam Pack, chronOS Strip, Vitoss Micromorsels, LifeInk500, Hyperelastic Bone, bioactive glass, P TCP powder, P TCP spray dried powder, hydroxyapatite powder, hydroxyapatite-coated bone screw, P TCP granules, hydroxyapatite granules, 3D printed structures, and ReBOSSIS. Structures herein may be of any form, including, without limitation, a granular form, a porous form, a powder, a putty (e.g., a moldable putty), a paste, fiber form, a coating on a solid surface (e.g., a coating on a medical device), and any combination thereof.

[0052] In some embodiments, the structure is a fiber. The fiber may be an electrospun fiber. In some embodiments, the fiber comprises a calcium containing compound and a bioabsorbable polymer. Example fibers include about 0-40 wt% bioabsorabable and 60-100% calcium containing compound. The calcium containing compound may comprise calcium phosphate, e.g, betatricalcium phosphate. The calcium containing compound may comprise calcium phosphate and silicon-doped vaterite (SiV). The bioabsorbable polymer may be PLGA. In some embodiments, the fiber comprises about 20-40% bioabsorbable polymer and about 60-80% calcium containing compound. In some embodiments, the fiber comprises about 30% bioabsorbable polymer and about 70% calcium containing compound.

[0053] The structures may be a variety of different shapes (e.g., a cross, a ladder, a sphere, an ellipsoid, a square, a triangular pyramid, a rod, a cone, a torus, or a wedge, or any combination thereof) and sizes (e.g., largest average diameter of about 1 mm to about 10 cm). In some embodiments, the structure is porous (e.g., about 90% to about 99% porous when dry (no hydration)).

[0054] Structure Formulations

[0055] In one aspect, provided herein are formulations for fabrication of structures. The structures include, without limitation, those described herein, including ink formulations for the preparation of a 3D printed scaffold. As a non-limiting example, the formulations include a ceramic material such as calcium phosphate (e.g., tricalcium phosphate, beta tricalcium phosphate, alphatricalcium phosphate), hydroxyapatite, fluorapatite, bone (e.g., demineralized bone), glasses (bioglasses) such as silicates, vanadates, and related ceramic minerals, or chelated divalent metal ions, or a combination thereof. In some embodiments, the ceramic material comprises beta -tricalcium phosphate (P-TCP). In some embodiments, the formulation is about 30-70, 30-65, 30-60, 30-55, 30-50, 30-45, 30-40, 30-35, 35-70, 35-65, 35-60, 35-55, 35-50, 35-45, 35-40, 40-70, 40-65, 40- 60, 40-55, 40-50, 40-45, 45-70, 45-65, 45-60, 45-55, 45-50, 50-70, 50-65, 50-60, 50-55, 55-70, 55-65, 55-60, 60-70, 60-65, or 65-70 percent ceramic by weight of the formulation. For instance, the formulation is about 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, or 70% ceramic by weight. In a non-limiting example, the formulation is about 60% ceramic by weight. In some embodiments, the ceramic is P-TCP. In some embodiments, the P-TCP is introduced into the formulation as a powder. In some embodiments, the formulation comprises one or more additional components. Non-limiting examples of additional components include water, polymer (including copolymer), antifoaming agent, dispersing agent, solvent, particulate or sacrificial pore former, blowing agent, and plasticizer.

[0056] In some embodiments, the formulation comprises one or more polymers, e.g., about 1, 2, 3, 4, or 5 polymers. Non-limiting examples of polymers include poly (ethylene oxide), polypropylene oxide), polyethylene glycol (PEG), and polyester. In some embodiments, the polymer is a water soluble polymer, e.g., PEG. In some embodiments, the formulation comprises a polymer that is about 5-30 percent by weight of the formulation. In some embodiments, the formulation comprises a polymer that is about 10-30 percent by weight of the formulation. In some embodiments, the formulation is about20-60 percenttotal polymerby weight. For instance, the total polymer includes two or more polymers in the formulation, where the total percentage of polymers in the formulationisabout20-60percentofthe weight of the formulation. In an example embodiment, a first polymer is present at about 5-15% by weight of the formulation, and a second polymer is present at about 5-15% by weight of the formulation. In some embodiments, the formulation is about 30 to about 50 percenttotal polymerby weight. As non -limiting examples, the formulation is about 35-45 percent total polymer by weight. In an example, the polymer comprises a poloxamer. Poloxamers are block copolymers of polyethylene oxide) (PEO) and polypropylene oxide) (PPO). A non-limiting example of a poloxamer is poloxamer 407, such as Pluronic®F-127. In some cases, the formulation comprises about 5-20, 5-15, 5-10, 10-20, 10-15, or 15-20 percent poloxamer 407 by weight. As another example, the polymer comprises polyethylene glycol (PEG). In some cases, the formulation comprises about 5-30, 5-25, 5-20, 5- 15, 5-10, 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight PEG. For instance, the formulation comprisesabout 5-30, or 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25 , 26, 27, 28, 29 or 30 percent by weight PEG. In some embodiments, there is a first PEG with a first molecular weight, and a second PEG with a second molecular weight. In some embodiments, PEG can have a molecular weight from 500 g / mol to 35,000 g / mol. In some cases, the molecular weight of PEG is about 500 g / mol, about 1,000 g / mol, about 1,500 g / mol, about 20,00 g / mol, about 2,500 g / mol, about 3,000 g / mol, about 3,500 g / mol, about 4,000 g / mol, about 4,500 g / mol, about 5,000 g / mol, about 5,500 g / mol, about 6,000 g / mol, about 6,500 g / mol, about 7,000 g / mol, about 7,500 g / mol, about 8,000 g / mol, about 8,500 g / mol, about 9,000 g / mol, about 9,500 g / mol, about 10,000 g / mol, about 10,500 g / mol, about 11,000 g / mol, about 11,500 g / mol, about 12,000 g / mol, about 12,500 g / mol, about 13,000 g / mol, about

[0057] 13.500 g / mol, about 14,000 g / mol, about 14,500 g / mol, about 15,000 g / mol, about 15,500 g / mol, about 16,000 g / mol, about 16,500 g / mol, about 17,000 g / mol, about 17,500 g / mol, about 18,000 g / mol, about 18,500 g / mol, about 19,000 g / mol, about 19,500 g / mol, about 20, 000 g / mol, about

[0058] 20.500 g / mol, about21,000 g / mol, about21,500 g / mol, about 22,000 g / mol, about22,500 g / mol, about 23,000 g / mol, about23,500 g / mol, about24,000 g / mol, about 24,500 g / mol, 25,000 g / mol,

[0059] 25.500 g / mol, 26,000 g / mol, 26,500 g / mol, 27,000 g / mol, 27,500 g / mol, 28,000 g / mol, 28,500 g / mol, 29,000 g / mol, 29,500 g / mol, 30,000 g / mol, 30,500 g / mol, 31,000 g / mol, 31,500 g / mol, 32,000 g / mol, 32,500 g / mol, 33,000 g / mol, 33,500 g / mol, 34,000 g / mol, 34,500 g / mol or about 35,000 g / mol. In a nonlimiting example embodiment, the formulation comprises PEG having a molecular weight of 1,500 g / mol. In a further nonlimiting example embodiment, the formulation comprises PEG having a molecular weight of 8,000 g / mol. In a further nonlimiting example embodiment, the formulation comprises PEG having a molecular weight of 20,000 g / mol. In a further nonlimiting example embodiment, the formulation comprises PEG having a molecular weight of 35,000 g / mol. In a nonlimiting example embodiment, the formulation comprises a first PEG at about 5 -15 percent by weight and a second PEG at about 5 -15 percent by weight. In a nonlimiting example embodiment, the formulation comprises a first PEG at about 15 percent by weight and a second PEG at about 15 percent by weight. In a nonlimiting example embodiment, the formulation comprises a first PEG at about 5 percent by weight and a second PEG at about 5 percent by weight. In a nonlimiting example embodiment, the formulation comprises a first PEG at about 10 percent by weight and a second PEG at about 10 percent by weight. The first PEG may have a lower molecular weight and a lower melt viscosity than the second PEG. For instance, the first PEG has a molecular weight of about 500-15,000 g / mol and the second PEG has a molecular weight of about 25,000-50,000 g / mol. As another example, the polymer comprises polydioxanone (PDS). In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10- 15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight PDS. For instance, the formulation comprises about 15-25, or 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25 percent by weight PDS. As another example, the polymer comprises poly -1-lactide. In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight poly -1-lactide. For instance, the formulation comprises about 15-25, or 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25 percent by weight poly -1-lactide. As another example, the polymer comprises a polyester. In some embodiments, the polyester comprises a biodegradable polyester such as polycaprolactone (PCL). In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight PCL. For instance, the formulation comprises about 15 -25, or 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25 percent by weight PCL. In some cases, the formulation comprises PCL having a molecular weight of 50,000 g / mol. In some embodiments, the polyester comprises a polyglycolide or poly(gly colic acid) (PGA). In some cases, the formulation comprises about 0.5- 20, 0.5-18, 0.5-16, 0.5-14, 0.5-12, 0.5-10, 0.5-8, 0.5-6, 0.5-4, 0.5-2, 1-20, 1-18, 1-16, 1-14, 1-12,

[0060] 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6, 2-4, 3-20, 3-18, 3-16, 3-14,

[0061] 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5- 12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percentby weightPGA. For instance, the formulation comprises about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 percentby weight PGA. In some cases, the PGA has a molecular weight of about 38,000-54,000. In some embodiments, the polyester comprises a polylactide, such as poly(D,L-lactide). In some cases, the formulation comprises about 0.5-20, 0.5-18, 0.5-16, 0.5-14, 0.5-12, 0.5-10, 0.5-8, 0.5-6, 0.5- 4, 0.5-2, 1-20, 1-18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10,

[0062] 2-8, 2-6, 2-4, 3-20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10,

[0063] 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percent by weight polylactide. For instance, the formulation comprises about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 percent by weight polylactide.

[0064] In some embodiments, the polymer comprises a copolymer. In some embodiments, the copolymer is presentin the formulation at about 10-30%by weight. In some cases, the copolymer comprises poly glycolide. In some cases, the copolymer comprises PCL and poly glycolide. For instance, the copolymer comprises about 80-99, 80-98, 80-97, 80-96, 80-95, 80-94, 80-93, 80-92, 80-91, 80-90, 80-89, 80-88, 80-87, 80-86, 80-85, 85-99, 85-98, 85-97, 85-96, 85-95, 85-94, 85- 93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90-95, 90-94, 90-93, 90-92, 90-91, 95-99, 95-98, 95-97, or 95-96 percent molar PCL, and about 1 -20, 1-18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6, 2-4, 3-20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percent molar poly glycolide. In some cases, the copolymer comprises about 90-95 percent by mole PCL and about 5-10 percent by mole poly glycolide. In some cases, the copolymer comprises PDS and polyglycolide. For instance, the copolymer comprises about 80-99, 80-98, 80-97, 80-96, 80-95, 80-94, 80-93, 80-92, 80-91, 80-90, 80-89, SO- 88, 80-87, 80-86, 80-85, 85-99, 85-98, 85-97, 85-96, 85-95, 85-94, 85-93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90-95, 90-94, 90-93, 90-92, 90-91, 95-99, 95-98, 95-97, or 95-96 percent molar PDS, and about 1 -20, 1-18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2- 16, 2-14, 2-12, 2-10, 2-8, 2-6, 2-4, 3-20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4- 16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percent molar polyglycolide. In some cases, the copolymer comprises about 90-95 percentby mole PDS and about 5-10 percentby mole polyglycolide. In some cases, the copolymer comprises PDS-glycolide copolymer. For instance, the formulation comprises about 10-30, 10- 25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, 25-30, or 20 percent by weight PDS- glycolide copolymer. In some cases, the copolymer comprises glycolide / L-lactide. In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight glycolide / L-lactide copolymer. For instance, the formulation comprises about 15-25, or 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25 percent by weight glycolide / L-lactide copolymer. In some cases, the copolymer comprises glycolide and lactide (e.g., L-lactide). For instance, the copolymer comprises about 80-99, 80-98, 80-97, 80-96, 80-95, 80-94, 80-93, 80-92, 80-91, 80-90, 80-89, 80-88, 80-87, 80-86, 80-85, 85-99, 85-98, 85-97, 85- 96, 85-95, 85-94, 85-93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90-95, 90-94, 90-93, 90-92, 90-91, 95-99, 95-98, 95-97, or 95-96 percent molar glycolide, and about 1-20, 1-18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6, 2-4, 3-20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5- 16, 5-14, 5-12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percent molar lactide (e.g., L- lactide). In some cases, the copolymer comprises about 85 -95 percent by mole glycolide and about 5-15 percentby mole lactide (e.g., L-lactide), e.g., glycolide / L-lactide copolymer (95 :5). In some cases, the copolymer comprises caprolactone / glycolide. In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight caprolactone / glycolide copolymer. For instance, the formulation comprises about 15- 25, or 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25 percent by weight caprolactone / glycolide copolymer. In some cases, the copolymer comprises caprolactone and glycolide. For instance, the copolymer comprises about 80-99, 80-98, 80-97, 80-96, 80-95, 80-94, 80-93, 80-92, 80-91, 80- 90, 80-89, 80-88, 80-87, 80-86, 80-85, 85-99, 85-98, 85-97, 85-96, 85-95, 85-94, 85-93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90-95, 90-94, 90-93, 90-92, 90-91, 95-99, 95-98, 95- 97, or 95-96 percent molar caprolactone, and about 1 -20, 1-18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6, 2-4, 3-20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percent molar glycolide. In some cases, the copolymer comprises about 85-95 percent by mole caprolactone and about 5-15 percent by mole glycolide, e.g., caprolactone / glycolide copolymer (95:5) or caprolactone / glycolide copolymer (90:10). In some cases, the copolymer comprises poly(D,L-lactide-co-glycolide) copolymer. For instance, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, 25-30, or 20 percent by weight poly(D,L-lactide-co-glycolide) copolymer. In some cases, the copolymer comprises lactide (e.g., poly(D,L-lactide)) and poly glycolide. For instance, the copolymer comprises about 35-65, 35-60, 35-55, 35-50, 35-45, 35-40, 40-65, 40-60, 40-55, 40- 50, 40-45, 45-65, 45-60, 45-55, 45-50, 50-65, 50-60, 50-55, 55-65, 55-60, 60-65 percentmolar lactide (e.g., poly(D,L-lactide)), and about 35-65, 35-60, 35-55, 35-50, 35-45, 35-40, 40-65, 40- 60, 40-55, 40-50, 40-45, 45-65, 45-60, 45-55, 45-50, 50-65, 50-60, 50-55, 55-65, 55-60, 60-65 percent molar glycolide, e.g., poly(D,L-lactide-co-glycolide) copolymer (50:50). In some cases, the copolymer compriseslactide (e.g. , L-lactide) and PDS. For instance, the copolymer comprises about 35-65, 35-60, 35-55, 35-50, 35-45, 35-40, 40-65, 40-60, 40-55, 40-50, 40-45, 45-65, 45-60, 45-55, 45-50, 50-65, 50-60, 50-55, 55-65, 55-60, 60-65 percentmolar PDS, and about 35-65, 35- 60, 35-55, 35-50, 35-45, 35-40, 40-65, 40-60, 40-55, 40-50, 40-45, 45-65, 45-60, 45-55, 45-50, 50-65, 50-60, 50-55, 55-65, 55-60, 60-65 percent molar lactide (e.g., L-lactide). In some cases, the copolymer comprises PDS-L-lactide copolymer. For instance, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, 25-30, or 20 percent by weight PDS-L-lactide copolymer. In some cases, the copolymer comprises dioxanone. In some cases, the copolymer comprises dioxanone and lactide (e.g., L-lactide). For instance, the copolymer comprises about 80-99, 80-98, 80-97, 80-96, 80-95, 80-94, 80-93, 80-92, 80-91, 80- 90, 80-89, 80-88, 80-87, 80-86, 80-85, 85-99, 85-98, 85-97, 85-96, 85-95, 85-94, 85-93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90-95, 90-94, 90-93, 90-92, 90-91, 95-99, 95-98, 95- 97, or 95-96 percent molar dioxanone, and about 1-20, 1-18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 14, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6, 2-4, 3-20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 8- 20, 8-18, 8-16, 8-14, 8-12, or 8-10 percent molar lactide (e.g., L-lactide). In some cases, the copolymer comprises about 85-95 percent by mole dioxanone and about 5-15 percent by mole lactide (e.g., L-lactide), e.g., dioxanone / L-lactide copolymer (90: 10).

[0065] In some instances, the copolymer has a faster resorption rate than a single polymer. For instance, the copolymers used in example embodiments of ink formulation #2 (polycaprolactone / polyglycolide copolymer (95 :5)), ink formulation #3 (polycaprolactone / polyglycolide copolymer (90: 10)), and ink formulation #4 (poly(D,L-lactide- co-glycolide) copolymer (50:50)) have faster resorption rates than polycaprolactone. The resorption rates vary from slowest to fastest as: poly-l-lactide, polycaprolactone, polycaprolactone / polyglycolide copolymer (95:5), polycaprolactone / glycolide copolymer (90: 10), polydioxanone / L-lactide copolymer (90:10), poly dioxanone, glycolide / L-lactide copolymer (95 :5), poly(D,L-lactide-co-glycolide) copolymer (50:50).

[0066] In some embodiments, the formulation comprises two or more polymers. In some embodiments, the formulation is about 5-30, 5-25, 5-20, 5-15, 5-10, 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight of a first polymer, and about 5-30, 5-25, 5-20, 5-15, 5-10, 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or25-30 percent by weight of a second polymer. In some embodiments, one polymer is water soluble, and another polymer is not water soluble. For instance, the water soluble polymer is removed from the scaffold after or during manufacture, and the non-water soluble polymer constitutes a structural element of the scaffold. In non-limiting examples, the formulation is about 10-30 percent by weight of a first polymer, and about 10-30 percentby weight of a second polymer, or about 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 percentby wei^it of the firstpolymer, and about 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 percentby weight of the second polymer. In some cases, the first and / or second polymer comprises PEG. In some cases, the firstpolymer comprises PCL and the second polymer comprises PEG. In some cases, the first polymer comprises PDS and the second polymer comprises PEG. In some cases, the firstpolymer comprises poly-l-lactide and the second polymer comprises PEG. In some cases, the first polymer comprises a copolymer and the second polymer comprises PEG. The copolymer may comprise PCL and poly glycolide (e.g., 95mol% poly caprolactone, 5mol% poly glycolide; 90mol% poly caprolactone, 10mol% poly glycolide). The copolymer may comprise polylactide (e.g., poly(D, L-lactide) and poly glycolide (e.g., 50mol% poly(D, L-lactide), 50mol% polyglycolide or poly(D,L-lactide-co-glycolide) copolymer (50:50)). The copolymer may comprise PDS-glycolide copolymer (e.g., 90mol% PDS, 10mol% poly glycolide). The copolymer may comprise PDS-L-lactide copolymer (e.g., 90mol% PDS, 10mol% L-lactide or dioxanone / L-lactide copolymer (90: 10)). The copolymer may comprise glycolide-L-lactide copolymer (e.g., 95mol% glycolide, 5mol% L-lactide or glycolide / L-lactide copolymer (95 :5)).

[0067] In some embodiments, the formulation comprises one or more particulates. The particulate may be a pore former, sometimes referred to as a sacrificial pore former. The particulate may be water soluble. The particulate may comprise a salt and / or sugar. Non-limiting examples of particulates include sodium chloride, calcium chloride, sucrose, trehalose (e.g., a, a trehalose dihydrate), and mannitol (e.g., D-mannitol). Other pore formers include water soluble polymers, such as PEG. In some cases, the particulate comprises sucrose. In some embodiments, the formulation comprises about 1 -10, 1-9, 1-8, 1-7, 1-6, 1-5, 2-10, 2-9, 2-8, 2-7, 2-6, 2-5, 3-10, 3-9, 3-8, 3-7, 3-6, 3-5, 4-10, 4-9, 4-8, 4-7, 4-6, 4-5, 5-10, 5-9, 5-8, 5-7, or 5-6 percent by weight particulate. In some cases, the formulation comprises about 1 -10%, or about 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10% particulate. For instance, about 1 -10% sucrose. In some embodiments, the particulate or pore former has an average size of about 1 micron to about 500 microns in diameter. For instance, about 1 micron to about 450 microns, about 1 micron to about 400 microns, about 1 micron to about 350 microns, about 1 micron to about 300 microns, about 1 micron to about 250 microns, about 1 micron to about 200 microns, about 1 micron to about 150 microns, about 50 microns to about 500 microns, about 50 microns to about 450 microns, about 50 microns to about 400 microns, about 50 microns to about 350 microns, about 50 microns to about 300 microns, about 50 microns to about 250 microns, about 50 microns to about 200 microns, about 50 microns to about 150 microns, about 100 microns to about 500 microns, about 100 microns to about 450 microns, about 100 microns to about 400 microns, about 100 microns to about 350 microns, about 100 microns to about 300 microns, about 100 microns to about 250 microns, about 100 microns to about 200 microns, about 100 microns to about 150 microns, about 150 microns to about 500 microns, about 150 microns to about 450 microns, about 150 microns to about 400 microns, about 150 microns to about 350 microns, about 150 microns to about 300 microns, about 150 microns to about 250 microns, or about 150 microns to about 200 microns in diameter. In some cases, the particular or pore former has an average size of about 50 microns to about 250 microns, about 60 microns to about 240 microns, about 70 microns to about 230 microns, about 80 microns to about 220 microns, or about 90 microns to about 210 microns in diameter. In some embodiments, the particulate of pore former has an average size of about 100 microns to about 200 microns, e.g., about 110 microns to about 190 microns, about 120 microns to about 180 microns, about 130 microns to about 170 microns, about 140 microns to about 160 microns, or about 100 microns, about 110 microns, about 120 microns, about 130 microns, about 140 microns, about 150 microns, about 160 microns, about 170 microns, about 180 microns, about 190 microns, or about 200 microns in diameter. In some embodiments, the particulate or pore former has an average size of about 150 microns in diameter. In some embodiments, upon removal of the particulate or pore former, a structure formed from the formulation has micropores that provide additional surface area to the structure for contact with a therapeutic agent as compared to a structure formed with a formulation lackingthe particulate or pore former. In some embodiments, the microporesof the structure have an average pore size of about 1 micron to about 500 microns, or about 50 microns to about 250 microns, or about 150 microns in diameter.

[0068] In some embodiments, the formulation comprises one or more blowing agents. In some embodiments, the blowing agent comprises about 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 6- 20, 6-18, 6-16, 6-14, 6-12, 6-10, 6-8, 8-20, 8-18, 8-16, 8-14, 8-12, 8-10, 10-20, 10-18, 10-16, 10- 14, 10-12, 5-15, or about 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, or 15 percent by weight blowing agent. In some cases, the blowing agent releases carbon dioxide base during printing to create a foamed structure that can increase porosity of the structure. Non-limiting examples of blowing agents include baking powder (e.g, monocalcium phosphate, sodium bicarbonate, corn starch) and azodicarbonamide. In some cases, the blowing agent comprises sodium bicarbonate. In some cases, the formulation comprises about5-15, orabout5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 percent by weight sodium bicarbonate. In some embodiments, the blowing agent provides for micropores in the structure having an average diameter of about 1 micron to about 500 microns, or about 50 microns to about 250 microns, or about 150 microns.

[0069] In some embodiments, a formulation comprises a ceramic material (e.g., P-TCP) and a polymer. Polymers include PEO, PPO, PDS, PEG, polyester, copolymers, or a combination thereof. In some embodiments, the formulation is about 30-70, 30-65, 30-60, 30-55, 30-50, 30- 45, 30-40, 30-35, 35-70, 35-65, 35-60, 35-55, 35-50, 35-45, 35-40, 40-70, 40-65, 40-60, 40-55, 40-50, 40-45, 45-70, 45-65, 45-60, 45-55, 45-50, 50-70, 50-65, 50-60, 50-55, 55-70, 55-65, 55- 60, 60-70, 60-65, or 65-70 percent ceramic material (e.g., P-TCP) by weight, e.g., about 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, or 70% ceramic material (e.g , P-TCP) by weight. In some cases, the formulation comprises about 5-20, 5-15, 5-10, 10-20, 10-15, or 15 -20 percent poloxamer 407 by weight. In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15- 25, 15-20, 20-30, 20-25, or 25-30 percent by weight PEG. In some cases, the formulation comprises about 5-15 percentby weight a first PEG and 5-15 percent by weight a second PEG. In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20- 30, 20-25, or 25-30 percent by weightPCL. In some cases, the formulation comprises about 10- 30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight PDS. In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20- 30, 20-25, or 25-30 percentby weight caprolactone / glycolide copolymer (95:5). In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight caprolactone / glycolide copolymer (90:10). In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight poly(D,L-lactide-co-glycolide) copolymer (50:50). In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percentby weight dioxanone / L-lactide copolymer (90:10). In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight glycolide / L-lactide copolymer (95 :5). In some cases, the formulation comprises about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percentby weight poly-

[0070] 1-lactide. In some embodiments, the formulation further comprises an antifoaming agent. In some embodiments, the formulation further comprises a dispersing agent. In some embodiments, the formulation further comprises a solvent. In some embodiments, the formulation further comprises a plasticizer. In some embodiments, the formulation further comprises a particulate or sacrificial pore former. In some cases, the formulation further comprises a blowing agent.

[0071] In some embodiments, a formulation comprises a ceramic material (e.g., P-TCP) and a particulate or sacrificial pore former. The particulate may be water soluble. Non-limiting examples of particulates include salts and sugars, e.g. , sodium chloride, calcium chloride, sucrose, trehalose (e.g. , a, a trehalose dihydrate), and mannitol (e.g. , D-mannitol). The pore former may be a water soluble polymer such as PEG. In some embodiments, the formulation is about 30-70, 30-65, 30-60, 30-55, 30-50, 30-45, 30-40, 30-35, 35-70, 35-65, 35-60, 35-55, 35-50, 35-45, 35- 40, 40-70, 40-65, 40-60, 40-55, 40-50, 40-45, 45-70, 45-65, 45-60, 45-55, 45-50, 50-70, 50-65, 50-60, 50-55, 55-70, 55-65, 55-60, 60-70, 60-65, or 65-70 percent ceramic material (e.g., P-TCP) by weight, e.g., about 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, or 70% ceramic material (e.g., P-TCP) by weight. In some embodiments, the formulation comprises about 1 -10, 1-9, 1-8, 1-7, 1-6, 1-5,

[0072] 2-10, 2-9, 2-8, 2-7, 2-6, 2-5, 3-10, 3-9, 3-8, 3-7, 3-6, 3-5, 4-10, 4-9, 4-8, 4-7, 4-6, 4-5, 5-10, 5-9, 5-8, 5-7, or 5-6 percentby weight particulate. In some embodiments, the particulate comprises sucrose. In some embodiments, the formulation comprises about 10-30% or about 5-15% percent by weight sacrificial pore former, such as a polymer. In some embodiments, the formulation further comprises water. In some embodiments, the formulation further comprises a polymer. In some embodiments, the formulation further comprises an antifoaming agent. In some embodiments, the formulation further comprises a dispersing agent. In some embodiments, the formulation further comprises a solvent. In some embodiments, the formulation further comprises a plasticizer. In some cases, the formulation further comprises a blowing agent.

[0073] In some embodiments, a formulation comprises a ceramic material (e.g., P-TCP) and a blowing agent. Non-limiting examples of blowing agents include baking powder (e.g., monocalcium phosphate, sodium bicarbonate, com starch) and azodicarbonamide. The blowing agent may comprise sodium bicarbonate. In some embodiments, the formulation is about 30-70, 30-65, 30-60, 30-55, 30-50, 30-45, 30-40, 30-35, 35-70, 35-65, 35-60, 35-55, 35-50, 35-45, 35- 40, 40-70, 40-65, 40-60, 40-55, 40-50, 40-45, 45-70, 45-65, 45-60, 45-55, 45-50, 50-70, 50-65, 50-60, 50-55, 55-70, 55-65, 55-60, 60-70, 60-65, or 65-70 percent ceramic material (e.g., P-TCP) by weight, e.g., about 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, or 70% ceramic material (e.g., P-TCP) by weight. In some embodiments, the blowing agent comprises about 5-20, 5-18, 5-16, 5-15, 5- 14, 5-12, 5-10, 5-8, 5-6, 6-20, 6-18, 6-16, 6-14, 6-12, 6-10, 6-8, 8-20, 8-18, 8-16, 8-14, 8-12, 8- 10, 10-20, 10-18, 10-16, 10-14, 10-12, 5-15, or about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 percent by weight blowing agent. In some cases, the formulation comprises about 5 -15, or about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 percent by weight sodium bicarbonate. In some embodiments, the formulation further comprises water. In some embodiments, the formulation further comprises a polymer. In some embodiments, the formulation further comprises an antifoaming agent. In some embodiments, the formulation further comprises a dispersing agent. In some embodiments, the formulation further comprises a solvent. In some embodiments, the formulation further comprises a plasticizer. In some embodiments, the formulation further comprises a particulate or sacrificial pore former.

[0074] In another aspect, a formulation comprises a ceramic material and one or more polymers. In some embodiments, the formulation comprises about 30% to about 70% a ceramic material (e.g., P-TCP). For instance, the formulation comprises about 30-70, 30-65, 30-60, 30-55, 30-50, 30-45, 30-40, 30-35, 35-70, 35-65, 35-60, 35-55, 35-50, 35-45, 35-40, 40-70, 40-65, 40-60, 40- 55, 40-50, 40-45, 45-70, 45-65, 45-60, 45-55, 45-50, 50-70, 50-65, 50-60, 50-55, 60-70, 60-65, 65-70, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, or 70 percentby weight a ceramic material e.g., P-TCP). In some embodiments, the formulation comprises a first polymer, e.g., about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by we it first polymer. The first polymer may be polycaprolactone (PCL). The first polymer may be polydioxanone (PDS). The first polymer may be poly-l-lactide. The first polymer may be a copolymer, e.g., caprolactone / glycolide copolymer, poly(D,L-lactide-co-glycolide) copolymer, dioxanone / L-lactide copolymer, or glycolide / L-lactide copolymer. In some embodiments, the formulation comprisesa second polymer, e.g., about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight second polymer. The first and / or second polymer may be water soluble or non-water soluble. In some embodiments, the formulation comprises a first polymer, a second polymer, and / or a third polymer. The third polymer may be water soluble or non-water soluble. The second polymer may be polyethylene glycol (PEG). The second polymer may be PEG with a MW of about 8000g / mol. The third polymer may be PEG. The third polymer may be PEG with a MW of about 35, OOOg / mol. In a non-limiting embodiment, the formulation comprises about 30-70%by weight ceramic, about 10-30% by weight a firstpolymer, and about 10-30% by weight a second polymer. In a non-limiting embodiment, the formulation comprises about 30-70% by weight ceramic, about 10-30% by weight a first polymer, and about 5-15% by weight a second polymer, and about 5-15% by weight of a third polymer. For example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PCL, and about 10-30% by weight PEG. As another example, the formulation may comprise about 30- 70% by weight P-TCP, about 10-30% by weight PCL, about 5-15% by weight PEG (8000 MW), and about 5-15% by weight PEG (35000 MW). As another example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PDS, and about 10-30% by weightPEG. As another example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PDS, about 5-15% by weight PEG (8000 MW), and about 5-15% by weight PEG (35000 MW). As another example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight poly-l-lactide, and about 10-30% by weight PEG. As another example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight poly-l-lactide, about 5-15%by weight PEG (8000 MW), and about 5-15% by weight PEG (35000 MW). As another example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight copolymer, and about 10-30% by weight PEG. As another example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight copolymer, about 5-15% by weight PEG (8000 MW), and about 5-15% by weight PEG (35000 MW). Non-limiting example co-polymers include caprolactone / glycolide copolymer, poly(D,L- lactide-co-glycolide) copolymer, dioxanone / L-lactide copolymer, or glycolide / L-lactide copolymer.

[0075] In some further embodiments, the formulation comprises a particulate and / or pore former. The particulate may be water soluble. In some cases, the particulate comprises sucrose. In some embodiments, the formulation comprises about 1 -10, 1-9, 1-8, 1-7, 1-6, 1-5, 2-10, 2-9, 2-8, 2-7, 2-6, 2-5, 3-10, 3-9, 3-8, 3-7, 3-6, 3-5, 4-10, 4-9, 4-8, 4-7, 4-6, 4-5, 5-10, 5-9, 5-8, 5-7, or 5-6 percent by weight particulate. For example, the formulation may comprise about 30 -70% by weight p-TCP, about 10-30% by weightPCL, about 10-30% by weightPEG, and about 1 -10% by weight particulate. In some embodiments, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PCL, PDS, poly-l-lactide, caprolactone / glycolide copolymer, poly(D,L-lactide-co-glycolide) copolymer, dioxanone / L-lactide copolymer, or glycolide / L- lactide copolymer, about 5-15% by weight 8000 MW PEG, about 5-15% by weight 35,000 MW PEG, and about 1-10% by weight particulate. In some embodiments, the formulation comprises PEG, and the PEG is a pore former. In some embodiments, the PEG is present at about 10-30% by weight, or about 5-15% by weight 8000 MW PEG and about 5-15% by weight 35,000 MW PEG.

[0076] In some further embodiments, the formulation comprises a blowing agent. In some cases, the blowing agent comprises sodium bicarbonate. In some embodiments, the formulation comprises about 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 6-20, 6-18, 6-16, 6-14, 6-12, 6-10, 6-8, 8-20, 8-18, 8-16, 8-14, 8-12, 8-10, 10-20, 10-18, 10-16, 10-14, 10-12, 5-15, or about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 percent by weight blowing agent. For example, the formulation may comprise ab out 30-70% by weight P-TCP, ab out 10-30% by weightPCL, ab out 10-30% by weight PEG, and about 5-20% by weight blowing agent. For example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PCL, PDS, poly-l-lactide, caprolactone / glycolide copolymer, poly(D,L-lactide-co-glycolide) copolymer, dioxanone / L- lactide copolymer, or glycolide / L-lactide copolymer, about 5-15% by weight 8000 MW PEG, about 5-15% by weight 35,000 MW PEG, and about 5-20% by weight blowing agent.

[0077] In some further embodiments, the polymer of the formulation is a copolymer, such as a PCL and poly glycolide copolymer. For instance, the copolymer comprises about 80-99, 80-98, 80-97, 80-96, 80-95, 80-94, 80-93, 80-92, 80-91, 80-90, 80-89, 80-88, 80-87, 80-86, 80-85, 85- 99, 85-98, 85-97, 85-96, 85-95, 85-94, 85-93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90-95, 90-94, 90-93, 90-92, 90-91, 95-99, 95-98, 95-97, or 95-96 percent molar PCL, and about

[0078] 1-20, 1-18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6,

[0079] 2-4, 3-20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percent molar poly glycolide. In some cases, the copolymer comprises about 90-95 percent by mole PCL and about 5-10 percent by mole polyglycolide. In an example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PCL and polyglycolide copolymer e.g., 95mol% polycaprolactone, 5mol% poly glycolide), and about 10-30% by weight PEG. In an example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PCL and poly glycolide copolymer (e.g., 90mol% poly caprolactone, 10mol% poly glycolide), and about 10-30% by weight PEG. In an example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PCL and polyglycolide copolymer (e.g., 90mol% poly caprolactone, 10mol% poly glycolide, which may be referred to as caprolactone / glycolide copolymer (90: 10)), and about 5-15% by weight 8000 MW PEG, about 5-15% by weight 35,000 MW PEG. In an example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PCL and polyglycolide copolymer (e.g., 95mol% poly caprolactone, 5mol% poly glycolide), and about 5 -15% by weight 8000 MW PEG, about 5-15% by weight 35,000 MW PEG.

[0080] In some further embodiments, the polymer of the formulation is a copolymer, such as a PDS and poly glycolide copolymer. For instance, the copolymer comprises about 80-99, 80-98, 80-97, 80-96, 80-95, 80-94, 80-93, 80-92, 80-91, 80-90, 80-89, 80-88, 80-87, 80-86, 80-85, 85- 99, 85-98, 85-97, 85-96, 85-95, 85-94, 85-93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90-95, 90-94, 90-93, 90-92, 90-91, 95-99, 95-98, 95-97, or 95-96 percent molar PDS, and about

[0081] 1-20, 1-18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6,

[0082] 2-4, 3-20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percent molar poly glycolide. In some cases, the copolymer comprises about 90-95 percent by mole PDS and about 5-10 percent by mole polyglycolide. In an example, the formulation may comprise about

[0083] 30-70% by weight P-TCP, about 10-30% by weight PDS and polyglycolide copolymer (e.g., 90mol% PDS, 10mol% polyglycolide), and about 10-30% by weight PEG. In an example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PDS and polyglycolide copolymer (e.g., 90mol% PDS, 10mol% polyglycolide), and about 5 -15% by weight 8000 MW PEG, about 5-15% by weight 35,000 MW PEG.

[0084] In some further embodiments, the polymer of the formulation is a copolymer, such as a poly(D-L-lactide) and glycolide copolymer. For instance, the copolymer comprises about 30-50,

[0085] 31-49, 32-48, 33-47, 34-46, 35-45, 36-44, 37-43, 38-42, 39-41, 80-99, 80-98, 80-97, 80-96, SO- 95, 80-94, 80-93, 80-92, 80-91, 80-90, 80-89, 80-88, 80-87, 80-86, 80-85, 85-99, 85-98, 85-97, 85-96, 85-95, 85-94, 85-93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90-95, 90-94, 90- 93, 90-92, 90-91, 95-99, 95-98, 95-97, or 95-96 percent molar poly(D-L-lactide), and about SOSO^ 1-49, 32-48, 33-47, 34-46, 35-45, 36-44, 37-43, 38-42, 39-41, 1-20, 1-18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6, 2-4, 3-20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5- 12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percent molar glycolide. In some cases, the copolymer comprises about 50 percent by mole poly(D-L-lactide), and about 50 percent by mole glycolide. In an example, the formulation may comprise about 30-70%by weight p-TCP, about 10-30% by weight poly(D-L-lactide) and glycolide copolymer (e.g., 50mol% poly(D-L- lactide), 50mol% glycolide), and about 10-30% by weightPEG. In an example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight poly(D-L-lactide) and glycolide copolymer (e.g., 50mol% poly(D-L-lactide, 50mol% polyglycolide), and about 5-15% by weight 8000 MW PEG, about 5-15% by weight 35,000 MW PEG.

[0086] In some further embodiments, the polymer of the formulation is a copolymer, such as a PDS and lactide copolymer. For instance, the copolymer comprises about 80-99, 80-98, 80-97, 80-96, 80-95, 80-94, 80-93, 80-92, 80-91, 80-90, 80-89, 80-88, 80-87, 80-86, 80-85, 85-99, 85- 98, 85-97, 85-96, 85-95, 85-94, 85-93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90-95, 90-94, 90-93, 90-92, 90-91, 95-99, 95-98, 95-97, or 95-96 percent molar PDS, and about 1-20, 1- 18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6, 2-4, 3- 20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percentmolar lactide. In some cases, the copolymer comprises about 90-95 percentby mole PDS and about 5-10 percent by mole lactide. In an example, the formulation may comprise about 30-70%by weight p-TCP, about 10-30% by weight PDS and lactide copolymer (e.g., 90mol% PDS, 10mol% lactide), and about 10-30% by weight PEG. In an example, the formulation may comprise about 30-70% by weight p-TCP, about 10-30% by weight PDS and lactide copolymer (e.g., 90mol%PDS, 10mol% lactide), and about 5-15% by weight 8000 MW PEG, about 5-15% by weight 35,000 MW PEG.

[0087] In some further embodiments, the polymer of the formulation is a copolymer, such as a glycolide and lactide copolymer. For instance, the copolymer comprises about 80 -99, 80-98, SO- 97, 80-96, 80-95, 80-94, 80-93, 80-92, 80-91, 80-90, 80-89, 80-88, 80-87, 80-86, 80-85, 85-99, 85-98, 85-97, 85-96, 85-95, 85-94, 85-93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90- 95, 90-94, 90-93, 90-92, 90-91, 95-99, 95-98, 95-97, or 95-96 percent molar glycolide, and about

[0088] 1-20, 1-18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6,

[0089] 2-4, 3-20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percent molar lactide. In some cases, the copolymer comprises about 90-95 percentby mole glycolide and about 5-10 percent by mole lactide. In an example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight glycolide and lactide copolymer (e.g., 95mol% glycolide, 10mol% lactide), and about 10-30% by weightPEG. In an example, the formulationmay comprise about 30-70% by weight P-TCP, about 10-30% by weight glycolide and lactide copolymer (e.g, 95mol% glycolide, 5mol% lactide), and about 5 -15% by weight 8000 MW PEG, about 5 -15% by weight 35,000 MW PEG.

[0090] In another aspect, a formulation comprises a ceramic material and one or more polymers. In some embodiments, the formulation comprises about 30% to about 70% a ceramic material (e.g., P-TCP). For instance, the formulation comprises about 30-70, 30-65, 30-60, 30-55, 30-50, 30-45, 30-40, 30-35, 35-70, 35-65, 35-60, 35-55, 35-50, 35-45, 35-40, 40-70, 40-65, 40-60, 40- 55, 40-50, 40-45, 45-70, 45-65, 45-60, 45-55, 45-50, 50-70, 50-65, 50-60, 50-55, 60-70, 60-65, 65-70, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, or 70 percentby weight a ceramic material (e.g., P-TCP). In some embodiments, the formulation comprises a first polymer, e.g., about l0-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percentby we it first polymer. The first polymer may be a copolymer. In some embodiments, the copolymer comprises a lactide (e.g., poly(D,L-lactide)) and poly glycolide. In some embodiments, the copolymer comprises poly(D,L-lactide-co-glycolide) copolymer. In some embodiments, the copolymer comprises about 50mol% poly(D,L-lactide) and about 50mol%polyglycolide. In some embodiments, the copolymer comprises caprolactone / glycolide (e.g., 90:10, 95 :5) copolymer, poly(D,L-lactide-co-glycolide) (e.g., 50:50) copolymer, dioxanone / L-lactide (e.g., 90:10) copolymer, or glycolide / L-lactide (e.g., 95 :5) copolymer. In some embodiments, the formulation comprises a second polymer, e.g., about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percentby weight second polymer. The second polymer may be polyethylene glycol (PEG). In a non-limiting embodiment, the formulation comprises about 30-70% by weight ceramic, about 10-30% by weight a first polymer, and about 10-30% by weight a second polymer. For example, the formulation may comprise about 30-70% by weight p-TCP, about 10-30% by weight copolymer, andabout 10-30%by weightPEG. In some embodiments, the formulation may comprise about 30-70% by weight p-TCP, about 10-30% by weight copolymer, and about 5-15% by weight 8000 MW PEG, about 5-15% by weight 35,000 MW PEG.

[0091] In some further embodiments, a f ormulation comprises a ceramic material and one or more polymers. In some embodiments, the formulation comprises about 30% to about 70% a ceramic material (e.g., P-TCP). For instance, the formulation comprises about 30-70, 30-65, 30-60, 30-55, 30-50, 30-45, 30-40, 30-35, 35-70, 35-65, 35-60, 35-55, 35-50, 35-45, 35-40, 40-70, 40-65, 40- 60, 40-55, 40-50, 40-45, 45-70, 45-65, 45-60, 45-55, 45-50, 50-70, 50-65, 50-60, 50-55, 60-70, 60-65, 65-70, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, or 70 percent by weight a ceramic material (e.g., P-TCP). In some embodiments, the formulation comprises a first polymer, e.g., about 10-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by weight firstpolymer. The firstpolymer may be a copolymer, such as a dioxanone and lactide (e.g, L-lactide) copolymer. For instance, the copolymer comprises about 80-99, 80-98, 80-97, 80-96, 80-95, 80-94, 80-93, 80-92, 80-91, 80-90, 80-89, 80-88, 80-87, 80-86, 80-85, 85-99, 85-98, 85- 97, 85-96, 85-95, 85-94, 85-93, 85-92, 85-91, 85-90, 90-99, 90-98, 90-97, 90-96, 90-95, 90-94, 90-93, 90-92, 90-91, 95-99, 95-98, 95-97, or 95-96 percent molar dioxanone, and about 1-20, 1- 18, 1-16, 1-14, 1-12, 1-10, 1-8, 1-6, 1-4, 1-2, 2-20, 2-18, 2-16, 2-14, 2-12, 2-10, 2-8, 2-6, 2-4, 3- 20, 3-18, 3-16, 3-14, 3-12, 3-10, 3-8, 3-6, 3-4, 4-20, 4-18, 4-16, 4-14, 4-12, 4-10, 4-8, 4-6, 5-20, 5-18, 5-16, 5-14, 5-12, 5-10, 5-8, 5-6, 8-20, 8-18, 8-16, 8-14, 8-12, or 8-10 percentmolar lactide. In some cases, the copolymer comprises about 90-95 percent by mole dioxanone and about 5-10 percent by mole lactide. In some embodiments, the formulation comprises a second polymer, e.g., about l0-30, 10-25, 10-20, 10-15, 15-30, 15-25, 15-20, 20-30, 20-25, or 25-30 percent by we it second polymer. The second polymer may be polyethylene glycol (PEG). In a non -limiting embodiment, the formulation comprises about 30-70% by weight ceramic, about 10-30% by weight a first polymer, and about 10-30% by weight a second polymer. For example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight copolymer, and about 10-30% by weight PEG In an example, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PDS and lactide copolymer (e.g., 90mol% dioxanone, 10mol% L-lactide), and about 10-30% by weight PEG. In some embodiments, the formulation may comprise about 30-70% by weight P-TCP, about 10-30% by weight PDS and lactide copolymer (e.g., 90mol% dioxanone, 10mol% L-lactide), and about 5-15% by weight 8000 W PEG, about 5-15% by weight 35,000 MW PEG.

[0092] In one aspect, the formulation has a low viscosity that may be useful during manufacture of a 3D printed structure for extruding through a small diameter nozzle. The nozzle may have a diameter of about 240 pm to about 500 pm or about 280 to about 450 pm, or about 240 to about 850pm e.g., about240, 260, 280, 300, 320, 340, 360, 380, 400, 420, 440, 460, 480, 500 , 520, 540, 560, 580, 600, 620, 640, 660, 680, 700, 720, 740, 760, 780, 800, 820, 840, or 850 pm. In a nonlimiting example embodiment, the formulation is melt-mixed in a dual asymmetric centrifugal mixer to create a homogenous liquid ink. A mixture of low and high viscosity PEG can be used to tailor the molten ink viscosity such that oozing ofmolten ink out of the 3D printer nozzle during non-print motions is minimized while still enabling flow through a 100’s of microns diameter nozzle when the screw extruder is engaged for print motions. Higher molecular weight PEG generally is stiffer and stronger than low molecular weight PEG, the incorporation of which also improves the mechanical strength and stiffness of the feedstock material.

[0093] In one aspect, the formulation has a higherviscosity thatmay be useful during manufacture by forming the formulation into a filament. The filament may then be used for fused filament fabrication.

[0094] In one aspect, the formulation is in the form of a filament. For instance, as further described in Example 2, ink formulations were prepared into filaments for use in 3D printing structures on a fused filament fabrication (FFF) 3D printer. In some embodiments, the filament formulation has a diameter of about 1 to about 3 mm, or about 1 to about 2.75 mm, about 1 to about2.5 mm, about 1 to about2.25 mm, about 1 to about2 mm, about 1 to about 1.75 mm, about 1 to about 1.5 mm, about 1.25 to about 3 mm, about 1.25 to about 2.75 mm, about 1.25 to about 2.5 mm, about 1.25 to about 2.25 mm, about 1.25 to about 2 mm, about 1.25 to about 1.75 mm, about 1.25 to about 1.5 mm, about 1.5 to about 3 mm, about 1.5 to about 2.75 mm, about 1.5 to about 2.5 mm, about 1.5 to about 2.25 mm, about 1.5 to about 2 mm, about 1.5 to about 1.75 mm, about 1.75 to about 3 mm, about 1.75 to about2.75 mm, about 1.75 to about2.5 mm, about 1.75 to about 2.25 mm, about 1.75 to about 2 mm, about 2 to about 3 mm, about 2 to about 2.75 mm, about 2 to about 2.5 mm, or about 2 to about 2.25 mm. As a non -limiting example, the filament formulation has a diameter of about 1.5 mm to about 2 mm, or about 1.5 mm, about 1.75 mm, or about 2 mm.

[0095] In one aspect, the formulation is in the form of a pellet. For instance, as further described in Example 2, ink formulations were prepared into pellets for use in 3D structures. In some embodiments, the pellets can be made into filaments. In some embodiments, pellets can be made into powders. In some embodiments, pellets have a length of about 1 to about 6 mm, or about 1 to about 5.5 mm, about 1 to about 5 mm, about 1 to about4.5 mm, about 1 to about4 mm, about 1 to about 3.5 mm, about 1 to about 3 mm, about 1 to about 2.5 mm, about 1 to about 2 mm, about 1 to about 1.5 mm, about 1.5 to about 6 mm, about 1 .5 to about 5.5 mm, about 1 .5 to about 5 mm, ab out 1.5 to ab out 4.5 mm , ab out 1.5 to ab out 4 mm , ab out 1 .5 to ab out 3.5 mm , ab out 1.5 to ab out 3 mm, about 1.5 to about 2.5 mm, about 2 to about 6 mm, about 2 to about 5.5 mm, about 2 to about 5 mm, about 2 to about 4.5 mm, about 2 to about 4 mm, about 2 to about 3.5 mm, about 2 to about 3 mm, about2 to about 2.5 mm, about2.5 to about 6 mm, about 2.5 to about 5.5 mm, about 2.5 to about 5 mm, about 2.5 to about 4.5 mm, about 2.5 to about 4 mm, about 2.5 to about 3.5 mm, about2.5 to about 3 mm, about 3 to about 6 mm, about 3 to about 5.5 mm, about 3 to about 5 mm, about 3 to about 4.5 mm, about 3 to about 4 mm, about 3 to about 3.5 mm, about 3.5 to about 6 mm, about 3.5 to about 5.5 mm, about 3.5 to about 5 mm, about 3.5 to about 4.5 mm, about 3.5 to about 4 mm, about 4 to about 6 mm, about 4 to about 5.5 mm, about 4 to about 5 mm, about 4 to about 4.5 mm, about 4.5 to about 6 mm, about 4.5 to about 5.5 mm, about 4.5 to about 5 mm, about 5 to about 6 mm, about 5 to about 5.5 mm, or about 5.5 to about 6 mm. As a nonlimiting example embodiment, the pellets have a length of about2.5 mm to about4.5 mm, or about2.5 mm, about 3 mm, about 3.5 mm, about 4 mm, or about4.5 mm. In some embodiments, a pellet encompasses a variety of different shapes including spears, rods, granules, blocks, particles, and particles of any suitable shape.

[0096] In one aspect, the formulation is in the form of a powder. In some embodiments, the powder could be produced from a pellet. In a nonlimiting example embodiment, components of the formulation are melt-mixed into homogenous ink, and cryomilled to form powder. In a nonlimiting example embodiment, components of the formulation are dissolvedin a solvent -based slurry and spray dried to form a powder. In some embodiments, powders are used in selective laser sintering.

[0097] 3D Printed Structures

[0098] In another aspect, provided herein are 3D printed structures. The structures may be prepared using a formulation and / or method of manufacture described herein. As used herein, structures include scaffolds, and vice versa.

[0099] In some embodiments a three-dimensional structure has micropores. The micropores may be formed after removal of a particulate or pore former. The micropores may be formed by a use of a blowing agent during formulation. In some embodiments, the micropores provide additional surface area to the structure for contact with a therapeutic agent as compared to a structure lacking micropores. In a non-limiting example, the therapeutic agent comprises a targeting moiety that is non-covalently bound to a ceramic material of the structure.

[0100] In some embodiments, the micropores have an average diameter of about 1 micron to about 500 microns. For instance, about 1 micron to about 450 microns, about 1 micron to about 400 microns, about 1 micron to about 350 microns, about 1 micron to about 300 microns, about 1 micron to about 250 microns, about 1 micron to about 200 microns, about 1 micron to about 150 microns, about 50 microns to about 500 microns, about 50 microns to about 450 microns, about 50 microns to about 400 microns, about 50 microns to about 350 microns, about 50 microns to about 300 microns, about 50 microns to about 250 microns, about 50 microns to about 200 microns, about 50 microns to about 150 microns, about 100 microns to about 500 microns, about 100 microns to about 450 microns, about 100 microns to about 400 microns, about 100 microns to about 350 microns, about 100 microns to about 300 microns, about 100 microns to about 250 microns, about 100 microns to about 200 microns, about 100 microns to about 150 microns, about 150 microns to about 500 microns, about 150 microns to about 450 microns, about 150 microns to about 400 microns, about 150 microns to about 350 microns, about 150 microns to about 300 microns, about 150 microns to about 250 microns, or about 150 microns to about 200 microns in diameter. In some cases, the micropores have an average diameter of about 50 microns to about 250 microns, about 60 microns to about240 microns, about 70 microns to about 230 microns, about 80 microns to about 220 microns, or about 90 microns to about 210 microns. In some embodiments, the micropores an average diameter of about 100 microns to about 200 microns, e.g., about 110 microns to about 190 microns, about 120 microns to about 180 microns, about 130 microns to about 170 microns, about 140 microns to about 160 microns, or about 100 microns, about 110 microns, about 120 microns, about 130 microns, about 140 microns, about 150 microns, about 160 microns, about 170 microns, about 180 microns, about 190 microns, or about 200 microns. In some embodiments, the micropores have an average diameter of about 150 microns.

[0101] In some embodiments, the micropores have an average diameter of about 1 micron to about 50 microns. For instance, about 1 micron to about 45 microns, about 1 micron to about 40 microns, about 1 micron to about 35 microns, about 1 micron to about 30 microns, about 1 micron to about 25 microns, about 1 micron to about 20 microns, about 1 micron to about 15 microns, about 1 micron to about 10 microns, about 10 microns to about 50 microns, about 10 microns to about 45 microns, about 10 microns to about 40 microns, about 10 microns to about 35 microns, about 10 microns to about 30 microns, about 10 microns to about 25 microns, about 10 microns to about20 microns, about 10 microns to about 15 microns, about20 microns to about 50 microns, about 20 microns to about 45 microns, about 20 microns to about 40 microns, about 20 microns to about35 microns, about20 microns to about30 microns, about 20 microns to about 25 microns, about 30 microns to about 50 microns, about 30 microns to about 45 microns, about 30 microns to about40 microns, about 30 microns to about35 microns, about40 micronsto about50 microns, or about 40 microns to about 45 microns.

[0102] In example embodiments, the microporosity of the scaffold results in a hydrophilic scaffold, i.e. liquid readily wicks throughout the scaffold via capillary forces from the interconnected microporosity. In some embodiments a three-dimensional structure has a density of about 1 g / cm3to about 3 g / cm3. In some embodiments a three-dimensional structure has a density of about 1 g / cm3to about2 g / cm3. (e.g., about 1, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1 .95, or 2 g / cm3or any value therebetween).

[0103] In some embodiments a three-dimensional structure has an open porosity of about 15% to about 50%, about 15% to about 45%, about 15% to about 40%, about 20% to about 50%, about 20% to about 45%, about 25% to about 40%, about 25% to about 50%, about 25% to about 45%, or about 25% to about 40%. In some embodiments, the open porosity is about 25% to about 40%, e.g., about 25%, 30%, 35%, or 40%, or any value therebetween).

[0104] In some embodiments a three-dimensional structure has a strut diameter of about 300 pm to about 600 pm, about 325 pm to about 600 pm, about 350 pm to about 600 pm, about 375 pm to about 600 pm, about 400 pm to about 600 pm, about 425 pm to about 600 pm, ab out 450 pm to about 600 pm, about 475 pm to about 600 pm, about 500 pm to about 600 pm, about 525 pm to about 600 pm, about 550 pm to about 600 pm, about 300 pm to about 575 pm, about 325 pm to about 575 pm, about 350 pm to about 575 pm, about 375 pm to about 575 pm, about 400 pm to about 575 pm, about 425 pm to about 575 pm, about 450 pm to about 575 pm, about 475 pm to about 575 pm, about 500 pm to about 575 pm, about 525 pm to about 575 pm, about 550 pm to about 575 pm, about 300 pm to about 550 pm, about 325 pm to about 550 pm, about 350 pm to about 550 pm, about 375 pm to about 550 pm, about 400 pm to about 550 pm, about 425 pm to about 550 pm, about 450 pm to about 550 pm, about 475 pm to about 550 pm, about 500 pm to about 550 pm, about 525 pm to about 550 pm, about 300 pm to about 525 pm, about 325 pm to about 525 pm, about 350 pm to about 525 pm, about 375 pm to about 525 pm, about 400 pm to about 525 pm, about 425 pm to about 525 pm, about 450 pm to about 525 pm, about 475 pm to about 525 pm, about 500 pm to about 525 pm, about 300 pm to about 500 pm, about 325 pm to about 500 pm, about 350 pm to about 500 pm, about 375 pm to about 500 pm, about 400 pm to about 500 pm, about 425 pm to about 500 pm, about 450 pm to about 500 pm, about 475 pm to about 500 pm, about 300 pm to about 475 pm, about 325 pm to about 475 pm, about 350 pm to about 475 pm, about 375 pm to about 475 pm, about 400 pm to about 475 pm, about 425 pm to about475 pm, about 450 pm to about 475 pm, about 300 pm to about 450 pm, about 325 pm to about 450 pm, about 350 pm to about 450 pm, about 375 pm to about 450 pm, about 400 pm to about 450 pm, about 425 pm to about 450 pm, about 300 pm to about 400 pm, about 325 pm to about 400 pm, about 350 pm to about 400 pm, or about 375 pm to about 400 pm, about 300 to about 850, about 325 to about 850, about 350 to about 850, about 375 to about 850, about 400 to about 850, about 425 to about 850, about 450 to about 850, about 475 to about 850, about 500 to about 850, about 525 to about 850, about 550 to about 850, about 575 to about 850, about 600 to about 850, about 625 to about 850, about 650 to about 850, about 675 to about 850, about 700 to about 850, about 725 to about 850, about 750to about 850, about 775 to about 850, about 800 to about 850, about 825 to about 850, about 300 to about 825, about 325 to about 825, about 350 to about 825, about 375 to about 825, about 400 to about 825, about 425 to about 825, about 450 to about 825, about 475 to about 825, about 500 to about 825, about 525 to about 825, about 550 to about 825, about 575 to about 825, about 600 to about 825, about 625 to about 825, about 650 to about 825, about 675 to about 825, about 700 to about 825, about 725 to about 825, about 750 to about 825, about 775 to about 825, about 800 to about 825, about 825 to about 825, about 300 to about 800, about 325 to about 800, about 350 to about 800, about 375 to about 800, about 400 to about 800, about 425 to about 800, about 450 to about 800, about 475 to about 800, about 500 to about 800, about 525 to about 800, about 550 to about 800, about 575 to about 800, about 600 to about 800, about 625 to about 800, about 650 to about 800, about 675 to about 800, about 700 to about 800, about 725 to about 800, about 750to about 800, about 775 to about 800, about 300 to about 775, about 325 to about 775, about 350 to about 775, about 375 to about 775, about 400 to about 775, about 425 to about 775, about 450 to about 775, about475 to about 775, about 500 to about 775, about 525 to about 775, about 550 to about 775, about 575 to about 775, about 600 to about 775, about 625 to about 775, about 650 to about 775, about 675 to about 775, about 700 to about 775, about 725 to about 775, about 750 to about 775, about 300 to about 750, about 325 to about 750, about 350 to about 750, about 375 to about 750, about 400 to about 750, about 425 to about 750, about450 to about 750, about 475 to ab out 750 , ab out 500 to about 750, about 525 to about 750, about 550 to about 750, about 575 to about 750, about 600 to about 750, about 625 to about 750, about 650 to about 750, about 675 to about 750, about 700 to about 750, about 725 to about 750, about 300 to about 725, about 325 to about 725, about 350 to about 725, about 375 to about 725, about 400 to about 725, about 425 to about 725, about 450 to about 725, about 475 to about 725, about 500 to about 725, about 525 to about 725, about 550 to about 725, about 575 to about 725, about 600 to about 725, about 625 to about 725, about 650 to about 725, about 675 to about 725, about 700 to about 725, about 300 to about 700, about 325 to about 700, about 350 to about 700, about 375 to about 700, about 400 to about 700, about 425 to about 700, about 450 to about 700, about 475 to about 700, about 500 to about 700, about 525 to about 700, about 550 to about 700, about 575 to about 700, about 600 to about 700, about 625 to about 700, about 650 to about 700, about 675 to about 700, about 300 to about 675, about 325 to about 675, about 350 to about 675, about 375 to about 675, about 400 to about 675, about 425 to about 675, about 450 to about 675, about475 to about 675, about 500 to about 675, about 525 to about 675, about 550 to about 675, about 575 to about 675, about 600 to about 675, about 625 to about 675, about 650 to about 675, about 300 to about 650, about 325 to about 650, about 350 to about 650, about 375 to about 650, about 400 to about 650, about 425 to about 650, about 450 to about 650, about 475 to about 650, about 500 to about 650, about 525 to about 650, about 550 to about 650, about 575 to about 650, about 600 to about 650, about 625 to about 650, about 300 to about 625, about 325 to about 625, about 350 to about 625, about 375 to about 625, about 400 to about 625, about 425 to about 625, about 450 to about 625, about 475 to about 625, about 500 to about 625, about 525 to about 625, about 550 to about 625, about 575 to about 625, or about 600 to about 625 pm.

[0105] In some embodiments, the structure comprises a ceramic material such as a calcium phosphate. In some embodiments, the structure comprises about 50-100, 50-95, 50-90, 50-85, 50- 80, 50-75, 50-70, 50-65, 50-60, 50-55, 55-100, 55-95, 55-90, 55-85, 55-80, 55-75, 55-70, 55-65, 55-60, 60-100, 60-95, 60-90, 60-85, 60-80, 60-75, 60-70, 60-65, 65-100, 65-95, 65-90, 65-85, 65- 80, 65-75, 65-70, 70-100, 70-95, 70-90, 70-85, 70-80, 70-75, 75-100, 75-95, 75-90, 75-85, 75-80, 80-100, 80-95, 80-90, 80-85, 85-100, 85-95, 85-90, 90-100, 90-95, 95-100, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,91, 92, 93, 94,95, 96, 97,98, 99, or 100 percent ceramic material. In some cases, the ceramic material is calcium phosphate, such as beta -tricalcium phosphate (0- TCP).

[0106] In a non-limiting example, a structure has about 50-90% ceramic material such as 0-TCP. In some cases, the structure has about 50, 55, 60, 65, 70, 75, 80, 85, or 90% ceramic material such as 0-TCP. In some embodiments, the structure has about 10-50% polymer such as poly caprolactone (PCL) or polydioxanone (PDS), or poly-l-lactide. In some cases, the structure has about 10, 15, 20, 25, 30, 35, 40, 45, or 50% polymer such as PCL or PDS or poly-l-lactide. Example structures include those having: about 85-90% ceramic (e.g., 0-TCP) and about 10-15% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 80-85% ceramic (e.g., 0-TCP) and about 15-20% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 75 -80% ceramic (e.g., 0-TCP) and about 20-25% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 70-75% ceramic (e.g., 0-TCP) and about25-30% polymer (e.g, PCL or PDS or poly-l-lactide) by weight, about 65-70% ceramic (e.g., 0-TCP) and about 30-35% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 60-65% ceramic (e.g., 0-TCP) and about 35-40% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 55-60% ceramic (e.g., 0-TCP) and about 4045% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 50-55% ceramic (e.g., 0-TCP) and about 45 -50% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 90% ceramic (e.g., 0-TCP) and about 10% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 89% ceramic (e.g., P-TCP) and about 11% polymer (e.g., PCL or PDS or poly-l-lactide)by weight, about 88% ceramic (e.g., P-TCP) and about 12% polymer (e.g., PCL orPDS or poly-l-lactide) by weight, about 87% ceramic (e.g., P-TCP) and about 13% polymer (e.g., PCL or PDS or poly-l- lactide) by weight, about 86% ceramic (e.g., P-TCP) and about 14% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 85% ceramic (e.g., P-TCP) and about 15% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 84% ceramic (e.g., P-TCP) and about 16% polymer (e.g., PCL orPDS or poly-l-lactide) by weight, about 83% ceramic (e.g., P-TCP) and about 17% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 82% ceramic (e.g., P-TCP) and about 18% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 81% ceramic (e.g., P- TCP) and about 19% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 80% ceramic (e.g., P-TCP) and about 20% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 79% ceramic (e.g., P-TCP) and about 21% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 78% ceramic (e.g., P-TCP) and about 22% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 77% ceramic (e.g., P-TCP) and about 23% polymer (e.g., PCL or PDS or poly-l- lactide) by weight, about 76% ceramic (e.g., P-TCP) and about 24% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 75% ceramic (e.g., P-TCP) and about 25% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 74% ceramic (e.g., P-TCP) and about 26% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 73% ceramic (e.g., P-TCP) and about 27% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 72% ceramic (e.g., P-TCP) and about 28% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 71% ceramic (e.g., P- TCP) and about 29% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 70% ceramic (e.g., P-TCP) and about 30% polymer (e.g., PCL orPDS or poly-l-lactide) by weight, about 69% ceramic (e.g., P-TCP) and about 31% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 68% ceramic (e.g., P-TCP) and about 32% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 67% ceramic (e.g., P-TCP) and about 33% polymer (e.g., PCL or PDS or poly-l- lactide) by weight, about 66% ceramic (e.g., P-TCP) and about 34% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 65% ceramic (e.g., P-TCP) and about 35% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 64% ceramic (e.g., P-TCP) and about 36% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 63% ceramic (e.g., P-TCP) and about 37% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 62% ceramic (e.g., P-TCP) and about 38% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about61% ceramic (e.g., P- TCP) and about 39% polymer (e.g., PCL orPDS or poly-l-lactide) by weight, about 60% ceramic (e.g., P-TCP) and about 40% polymer (e.g., PCL orPDS or poly-l-lactide) by weight, about 59% ceramic (e.g., P-TCP) and about 41% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 58% ceramic (e.g., P-TCP) and about 42% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 57% ceramic (e.g., P-TCP) and about 43% polymer (e.g., PCL or PDS or poly-l- lactide) by weight, about 56% ceramic (e.g., P-TCP) and about 44% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 55% ceramic (e.g., P-TCP) and about 45% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 54% ceramic (e.g., P-TCP) and about 46% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 53% ceramic (e.g., P-TCP) and about 47% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 52% ceramic (e.g., P-TCP) and about 48% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, about 51% ceramic (e.g., P- TCP) and about 49% polymer (e.g., PCL or PDS or poly-l-lactide) by weight, and about 50% ceramic (e.g., P-TCP) and about 50% polymer (e.g., PCL or PDS or poly-l-lactide) by weight.

[0107] The structure may be manufactured using 3D printing from an ink comprising about 30- 70% by weight P-TCP powder, about 10-30% by weight first polymer, and about 10-30% by weight second polymer. In some cases, the structure is manufactured using 3D printing from an ink comprising about 30-70% by weight P-TCP powder, about 10-30% by weight first polymer, and about 5-15% by weight second polymer, and about 5-15% third polymer. In some cases structure may be manufactured using 3D printing from an ink comprising about 30 -70% by weight P-TCP powder, about 10-30% by weight first polymer, and about 5-15% by weight second polymer (8000 MWPEG) and about 5-15% by weightthird polymer (35,000 MW PEG). In some cases, the first polymer comprises PCL. In some cases, the first polymer comprises PDS. In some cases the first polymer comprises poly-l-lactide. In some cases, the second polymer comprises PEG. In some cases, the third polymer comprises PEG. In some cases, the ink further comprises about 1-10% by weight particulate (e.g., sucrose). In some cases, the ink further comprises about 5-20% blowing agent (e.g., sodium bicarbonate).

[0108] In some embodiments the three-dimensional structure has a density of about 1 g / cm3to about2 g / cm3or about 1 g / cm3to about 1.5 g / cm3. In some embodiments the three-dimensional structure has an open porosity of about 20% to about 40%, about 25% to about 35%, e.g., about 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35%. In some embodiments a three- dimensional structure has a strut diameter of about 300 pm to about 900 pm, about 300 pm to about 400 pm, or about 500 pm to about 900 pm.

[0109] In some embodiments the three-dimensional structure has a density of about 1 g / cm3to about 2 g / cm3or about 1.25 g / cm3to about 1.75 g / cm3. In some embodiments the three- dimensional structure has an open porosity of about 20% to about 40%, about 25% to about 35%, e.g., about 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35%. In some embodiments a three-dimensional structure has a strut diameter of about400 pm to about 500 pm, about 400 pm to about 450 pm, or about 425 pm to about 450 pm.

[0110] In some embodiments the three-dimensional structure has a density of about 1 g / cm3to about2 g / cm3or about 1 g / cm3to about 1.5 g / cm3. In some embodiments the three-dimensional structure has an open porosity of about 30% to about 50%, about 35% to about 45%, e.g., about 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, or 45%. In some embodiments a three- dimensional structure has a strut diameter of about 325 pm to about 425 pm, about 350 pm to about 400 pm, or about 360 pm to about 390 pm.

[0111] In some embodiments the three-dimensional structure has a density of about 1 g / cm3to about2 g / cm3or about 1 g / cm3to about 1.5 g / cm3. In some embodiments the three-dimensional structure has an open porosity of about 30% to about 50%, about 35% to about 45%, e.g., about 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, or 45%. In some embodiments a three- dimensional structure has a strut diameter of about 350 pm to about 450 pm, about 350 pm to about 400 pm, or about 380 pm to about 405 pm.

[0112] In a non-limiting example, a structure has about 50-90% ceramic material such as P-TCP. In some cases, the structure has about 50, 55, 60, 65, 70, 75, 80, 85, or 90% ceramic material such as P-TCP. In some embodiments, the structure has about 10-50% copolymer such as polycaprolactone / polyglycolide copolymer (PCL / PG A, e.g., 90: 10, 95 :5), poly(D,L-lactide-co- glycolide) copolymer (PLGA, e.g., 50:50), PDS-glycolide copolymer (PDS / PGA, e.g., 90:10), PDS-L-lactide copolymer (PDS / PLA, e.g., 90:10), or Dioxanone / L-lactide copolymer (e.g., 90:10). In some cases, the structure has about 10, 15, 20, 25, 30, 35, 40, 45, or 50% polymer such as PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide). Example structures include those having: about 85-90% ceramic (e.g., P-TCP) and about 10-15% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, or Dioxanone / L-lactide) by weight, about 80-85% ceramic (e.g., P-TCP) and about 15-20% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 75-80% ceramic (e.g., P-TCP) and about20-25% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide- co-glycolide)) by weight, about 70-75% ceramic (e.g., P-TCP) and about 25-30% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 65-70% ceramic (e.g., P-TCP) and about30-35% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L- lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 60-65% ceramic (e.g., P-TCP) and about 35-40% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L- lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 55-60% ceramic (e.g., P-TCP) and about 40-45% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 50-55% ceramic (e.g., P-TCP)and about45-50%polymer(e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide- co-glycolide)) by weight, about 90% ceramic (e.g., P-TCP) and about 10% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 89% ceramic (e.g., P- TCP) and about 11% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L- lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 88% ceramic (e.g., P-TCP) and about 12% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 87% ceramic (e.g., P-TCP) and about 13% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 86% ceramic (e.g., P-TCP) and about 14% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide- co-glycolide)) by weight, about 85% ceramic (e.g., P-TCP) and about 15% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 84% ceramic (e.g., P- TCP) and about 16% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L- lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 83% ceramic (e.g., P-TCP) and about 17% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 82% ceramic (e.g., P-TCP) and about 18% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 81% ceramic (e.g., P-TCP) and about 19% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide- co-glycolide)) by weight, about 80% ceramic (e.g., P-TCP) and about 20% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 79% ceramic (e.g., P- TCP) and about 21% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L- lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 78% ceramic e.g., P-TCP) and about 22% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 77% ceramic (e.g., P-TCP) and about 23% polymer e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 76% ceramic (e.g., P-TCP) and about 24% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide- co-glycolide)) by weight, about 75% ceramic e.g., P-TCP) and about 25% polymer e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 74% ceramic e.g., P- TCP) and about 26% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L- lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 73% ceramic (e.g., P-TCP) and about 27% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 72% ceramic (e.g., P-TCP) and about 28% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 71% ceramic (e.g., P-TCP) and about 29% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide- co-glycolide)) by weight, about 70% ceramic e.g., P-TCP) and about 30% polymer e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 69% ceramic e.g., P- TCP) and about 31% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L- lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 68% ceramic e.g., P-TCP) and about 32% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 67% ceramic (e.g., P-TCP) and about 33% polymer e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 66% ceramic (e.g., P-TCP) and about 34% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide- co-glycolide)) by weight, about 65% ceramic (e.g., P-TCP) and about 35% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 64% ceramic (e.g., 0- TCP) and about 36% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L- lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 63% ceramic e.g., 0-TCP) and about 37% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 62% ceramic e.g., 0-TCP) and about 38% polymer e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 61% ceramic e.g., 0-TCP) and about 39% polymer e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide- co-glycolide)) by weight, about 60% ceramic e.g., 0-TCP) and about 40% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 59% ceramic (e.g., 0- TCP) and about 41% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L- lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 58% ceramic (e.g., 0-TCP) and about 42% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 57% ceramic (e.g., 0-TCP) and about 43% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 56% ceramic (e.g., 0-TCP) and about 44% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide- co-glycolide)) by weight, about 55% ceramic (e.g., 0-TCP) and about 45% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 54% ceramic (e.g., 0- TCP) and about 46% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L- lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 53% ceramic (e.g., 0-TCP) and about 47% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight, about 52% ceramic (e.g., 0-TCP) and about 48% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide-co-glycolide)) by weight, about 51% ceramic (e.g., 0-TCP) and about 49% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, orPoly(D,L-lactide- co-glycolide)) by weight, and about 50% ceramic (e.g., P-TCP) and about 50% polymer (e.g., PCL / PGA, PDS / PGA, PDS / PLA, PLGA, Dioxanone / L-lactide, Caprolactone / Glycolide, Glycolide / L-lactide, or Poly(D,L-lactide-co-glycolide)) by weight.

[0113] In some embodiments, the compositions of ink formulations herein are varied to optimize specific surface area. The surface area may be optimized for combination with a certain therapeutic agent. For example, the structure has a surface area of about 0.2-2 m2 / g for combination with a BMP protein (e.g., tBMP-2). In some embodiments, the surface area of a structure herein is about 0.2-2, 0.2-1.8, 0.2-1.6, 0.2-1 .4, 0.2-1 .2, 0.2-1, 0.2-0.8, 0.2-0.6, 0.2-0.4, 0.4-2, 0.4-1 .8, 0.4-1 .6, 0.4-1.4, 0.4-1.2, 0.4-1, 0.4-0.8, 0.4-0.6, 0.6-2, 0.6-1 .8, 0.6-1.6, 0.6-1.4, 0.6- 1.2, 0.6-1, 0.6-0.8, 0.8-2, 0.8-1.8, 0.8-1 .6, 0.8-1.4, 0.8-1.2, 0.8-1, 1-2, 1-1.8, 1-1.6, 1-1.4, 1-1.2, 1.2-2, 1 .2-1.8, 1.2-1.6, 1.2-1.4, 1.4-2, 1.4-1.8, 1.4-1.6, 1.6-2, 1.6-1.8, or 1.8-2 m2 / g. In some embodiments, the surface area is calculated by Brunauer-Emmett-Teller (BET) by gas physisorption.

[0114] In some embodiments, the compositions of ink formulations herein are varied to optimize resorption rate of one or more materials of the scaffold. For instance, the polymers are selected based on resorption rate. The resorption rates vary from slowest to fastest as: poly caprolactone, polycaprolactone / polyglycolide copolymer (95 :5), polycaprolactone / glycolide copolymer (90: 10), polydioxanone / L-lactide copolymer (90:10), poly (D,L-lactide-co-glycolide) copolymer (50:50).

[0115] Methods of Manufacture

[0116] In another aspect, provided are methods of manufacturing a structure using 3D printing techniques.

[0117] In some embodiments, the method comprises syringe-based melt extrusion bioprinting Example inks for this method may be low in viscosity for extrusion of the ink through a narrow nozzle. Non-limiting example methods of manufacturing using this method are described in Example 2, for instance, with regard to printing ink formulations #1, #2, #3, #4.

[0118] In one aspect, the method is an extrusion based method comprising a 3D printing method that extrudes the material out of a nozzle.

[0119] In some embodiments, the extrusion based method encompasses bioprinting (syringe - based pneumatic printing) or Fused Granular Fabrication (FGF) where pellets of feedstock are fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle. In some embodiments, the inks are formed into small (e.g., 2-5 mm) pellets or granules. In example embodiments, the ink comprises a plurality of pellets or granules having an average diameter of X, wherein at least 90% of the plurality of pellets or granules have an individual diameter of X + / - 0.5 mm. For example, the plurality of pellets or granules have an average diameter of 2 mm, where at least 90% of the plurality of pellets or granules have an individual diameter of 1.5-2.5 mm. As another example, the plurality of pellets or granules have an average diameter of 5 mm, where at least 90% of the plurality of pellets or granules have an individual diameter of 4.5-5.5 mm.

[0120] In some embodiments, the method comprises fused filament fabrication (FFF). Example inks for this method may be formed into filaments for printing on FFF 3D printers. Non -limiting example methods of manufacturing using this method are described in Example 2, for instance, with regard to printing ink formulations #5 and #6.

[0121] In some embodiments, the method comprises pelletized fused deposition modeling. Fused deposition modeling (FDM) is an additive manufacturing process. Three dimensional objects are formed through extrusion and deposition of individual layers of thermoplastic materials. FDM involves the melt extrusion of filament materials through a heated nozzle and deposition as thin solid layers on a platform. A thermoplastic polymer material is fed into a temperature-controlled FDM extrusion head and it is heated to a semi-liquid state. Afterward, the FDM extrusion head extrudes and deposits the material in ultra-thin layers onto a base with precision. The material solidifies, laminating to the preceding layer. In this way, parts are fabricated in layers, where each layer is built by extruding a small bead of material, called a road, in a particular pattern, such that the layer is covered with the adjacent roads. After each layer is completed, extrusion head height is increased and sub sequent layers arebuiltto construct the part. Usually, FDMis used to fabricate solid models. In order to fabricate porous structures, raster fill gaps have a positive value which is applied to impart a channel within a build layer. Arranged in a regular manner, the channels are interconnected even in three dimensions. Layer by layer fabrication allows design of a pore morphology which varies across a scaffold structure.

[0122] In some embodiments, the method comprises selective laser sintering (SLS). Selective laser sintering (SLS) is a process wherein a dispenser deposits layers of powdered material into a target area. There is a laser control mechanism that typically includes a computer with the article design stored on it. The laser control mechanism modulates and moves a laser beam to selectively irradiate the powder layer within defined boundaries of the design, melting the powder on which the laser beam falls. This is done to selectively sinter sequential powder layers. The method produces a completed article comprised of a plurality of layers sintered together. In some embodiments, after 3D printing, the resulting subject is soaked in waterto dissolve certain components of the ink, e.g., PEG, particulate (e.g., pore forming agent, sucrose), blowing agent (e.g., sodium bicarbonate), or a combination thereof. The structure may then be dried, sterilized, treated with a therapeutic as described elsewhere herein, or a combination thereof.

[0123] Any of the 3D-printed structures described herein can be coated with a tetherable protein (for example, tBMP2). Following completion of the structures using any of the methods discussed herein, the structures can be washed in an acidic sodium acetate buffer. This can be one, two, or more washes. The washing can then be followed by a two -hour incubation of the structures in sodium acetate buffer that contains a 1 mg / mL concentration of tBMP2 protein. The tetherable tBMP2 binds to the P-TCP surface of the implantable structures in a monolayer.

[0124] In further embodiments, the ink formulations discussed herein can include a light-sensitive resin that is mixed with the ceramic powder for digital light processing (DLP), an additive manufacturing technique that is faster than robocasting or melt extrusion. Components in a photosensitive, ceramic-filled resin for DLP 3D printing of bone implants typically include ceramic powder (e.g., P-TCP, hydroxyapatite, bioglass, typically <10 pm particle size), one or more crosslinking acrylates or methacrylates (e.g., polyethylene glycol diacrylate, poly caprolactone methacrylate), a plasticizer to reduce resin viscosity (e.g., water), a dispersant to promote breakdown of powder agglomerates (e.g., Darvan® 821 -A), photoinitiator to initiate the photocrosslinking reaction (e.g., Lithium phenyl-2,4,6-trimethylbenzoylphosphinate), and a photoabsorber to retain high x-y resolution (e.g., tartrazine). Once resin formulations are prepared by asymmetric centrifugal mixing of the components, the ink is exposed layer by layer to a DLP image, causing the lighted pixels to selectively solidify when the resin encounters the light. Once the implantable structure has been built up layer by layer, it can be thermally processed to bum out the included polymer and densify the ceramic (e.g., a polyethylene glycol diacrylate- containing resin), or left as-is, resulting in a flexible ceramic / polymer composite implant (e.g., a poly caprolactone methacrylate-containing resin).

[0125] Devices

[0126] In another aspect, provided are device compositions and kits comprising a structure (e.g., 3D printed, fiberous, or other scaffold) described herein and a therapeutic agent. In some embodiments, a device comprises the therapeutic agent connected to, dispersed within, or otherwise combined with the structure. As used herein, a therapeutic agent is inclusive of a plurality of therapeutic agents, such as 2, 3, 4, or 5 therapeutic agents. Therapeutic agents

[0127] In some embodiments, the therapeutic agent comprises a bone material. In some embodiments, the bone material comprises an autologous bone graft. In some embodiments, the bone material comprises a bone allograft. In some embodiments, the bone material comprises demineralized bone matrix. In some embodiments, the bone material comprises a comminuted bone material. The comminuted bone material may include pulverized bone. In some embodiments, the bone material includes at least a portion of a fresh bone, freeze-dried bone, frozen bone, or cadaveric bone, or a combination thereof. In some embodiments, the bone material comprises a cortical bone graft material. In some embodiments, the bone material comprises a cancellous bone graft material. In some embodiments, the bone material is shaped as a disc, a wafer, a wedge, or a custom shape designedto fill avoid in abone ora structure, such as a structure described herein. In some embodiments, the bone material is a powder, a putty, a paste, a coating an aerosol, a scaffold, a substrate, a liquid, or any combinations thereof. The bone material may be a hybrid, e.g., comprising one or more synthetic materials and one or more naturally -derived materials.

[0128] In some embodiments, the therapeutic agent comprises a bone material with a polymer carrier. In some embodiments, the polymer carrier enhances the handling properties of the bone material, e.g., demineralized bone matrix. In some embodiments, the polymer carrier is a biodegradable polymer. In some embodiments, the polymer carrier may include proteins, polysaccharides, cellulose, synthetic polymers (e.g., poly lactide -co-gly colic acid (PLGA)), surface demineralized bone, mineralized bone, nondemineralized cancellous scaffolds, demineralized cancellous scaffolds, cancellous chips, particulate, demineralized, guanidine extracted, species-specific (allogeneic) bone, specially-treated, particulate, protein extracted, demineralized, xenogenic bone, collagen, synthetic hydroxyapatite, synthetic calcium phosphate materials, tricalcium phosphate, sintered hydroxyapatite, settable hydroxyapatite, polylactide polymers, polyglycolide polymers, polylactide-co-glycolide copolymers, tyrosine polycarbonate, calcium sulfate, collagen sheets, settable calcium phosphate, polymeric cements, settable polyvinyl alcohols, polyurethanes, resorbable polymers, liquid settable polymers, and other biocompatible settable materials. The polymer carrier may further include a polyol (including glycerol or other polyhydroxy compound), a polysaccharide (including starches), a hydrogel (including alginate, chitosan, dextran, pluronics, N,O-carboxymethylchitosan glucosamine (NOCC)), hydrolyzed cellulose, or a polymer (including polyethylene glycol). In some embodiments, the polymer carrier may prevent contact between the demineralized bone matrix and activating agents (e.g., water, enzymes, etc.) and / or degradatory enzymes. In some embodiments, the bone material is a comminuted bone material. In some instances, the comminuted bone material includes pulverized bone. Comminuted bone material includes bone material having a particle size that is less than the particle size in an unprocessed bone (e.g., a bone that has not been comminuted). Non-limiting examples of methods and / or techniques to comminute bone material include grinding, pulverizing, milling, blending sectioning, crushing, triturating, disintegrating, cutting, and any combination thereof. In some embodiments, the b one material is comminuted at a temperature that is less than 4 degrees Celsius. In some embodiments, the bone material is comminuted using a cryogenic tool (e.g., a cryogenic grinder) that reduces the heat generated by the pulverization of bone during the comminuting process.

[0129] In some embodiments, the bone material includes at least a portion of a fresh bone, f reeze- dried bone, frozen bone, cadaveric bone, or a combination thereof. In some examples, the bone material is a cortical bone material. In some embodiments, the bone material is a cancellous bone graft material. In some embodiments, the bone material is a trabecular bone graft material. In some instances, the bone material is a periosteum bone graft material.

[0130] In some embodiments, the therapeutic agent comprises bone material and a mammalian growth factor. The mammalian growth factor may be tethered or otherwise bound to the bone material, e.g., via a targeting peptide as described herein.

[0131] In some embodiments, the therapeutic agent comprises a tissue material. In some embodiments, the tissue material comprises an autologous tissue graft. In some embodiments, the tissue material comprises a tissue allograft. In some embodiments, the tissue material includes at least a portion of a fresh tissue, freeze-dried tissue, frozen tissue, or cadaveric tissue, or a combination thereof. In some embodiments, the tissue material is shaped as a disc, a wafer, a wedge, or a custom shape designed to fill a void in a tissue or a structure, such as a structure described herein. In some embodiments,thetissuematerial is apowder, aputty, apaste, a coating, an aerosol, a scaffold, a substrate, a liquid, or any combinations thereof. The tissue material may be a hybrid, e.g., comprising one or more synthetic materials and one or more naturally -derived materials.

[0132] In some instances, the tissue material is a soft tissue graft. In some embodiments, the soft tissue graft is a cartilage graft. In some embodiments, the soft tissue graft is a skin tissue, adipose tissue, placental tissue, amniotic membrane, tendon tissue, ligament tissue, gingival tissue, connective tissue, or any combination thereof. In some embodiments, the therapeutic agent comprises tissue material and a mammalian growth factor. The mammalian growth factor may be tethered or otherwise bound to the tissue material, e.g., via a targeting peptide as described herein.

[0133] In some embodiments, the therapeutic agent comprises a mammalian growth factor or a functional portion thereof. Mammalian growth factors can be osteoinductive molecules that are capable of initiating and enhancing the bone repair process. A functional portion of the mammalian growth factor is a region that has a therapeutic effect. For instance, a functional portion of a mammalian growth factor is osteoinductive. As another example, a functional portion of a mammalian growth factor is capable of initiating and / or enhancing bone repair. A functional portion of a mammalian growth factor may have osteogenic activity.

[0134] Non-limiting examples of mammalian growth factors are described herein. In some instances, the mammalian growth factor comprises: epidermal growth factor (EGF), platelet derived growth factor (PDGF), insulin like growth factor (IGF-1), fibroblast growth factor (FGF), fibroblast growth factor 2 (FGF2), fibroblast growth factor 18 (FGF18), transforming growth factor alpha (TGF-a), transforming growth factor beta (TGF-P), transforming growth factor beta 1 (TGF-pi), transforming growth factor beta 3 (TGF-P3), osteogenic protein 1 (OP-1), osteogenic protein 2 (OP-2), osteogenic protein 3 (OP-3), bone morphogenetic protein 2 (BMP -2), bone morphogenetic protein 3 (BMP-3), bone morphogenetic protein 4 (BMP-4), bone morphogenetic protein 5 (BMP-5), bone morphogenetic protein 6 (BMP-6), bone morphogenetic protein 7 (BMP- 7), bone morphogenetic protein (BMP-9), bone morphogenetic protein 10 (BMP-10), bone morphogenetic protein 11 (BMP-11), bone morphogenetic protein 12 (BMP-12), bone morphogenetic protein 13 (BMP-13), bone morphogenetic protein 15 (BMP-15), delta-like ligand-4 (DLL4), dentin phosphoprotein (DPP), vegetal related growth factor (Vgr), growth differentiation factor 1 (GDF-1), growth differentiation factor 3 (GDF-3), growth differentiation factor 5 (GDF-5), growth differentiation factor 6 (GDF-6), growth differentiation factor 7 (GDF- 7), growth differentiation factor 8 (GDF8), growth differentiation factor 11 (GDF11), growth differentiation factor 15 (GDF15), vascular endothelial growth factor (VEGF), hyaluronic acid binding protein (HABP), and collagen binding protein (CBP), fibroblast growth factor 18 (FGF- 18), keratinocyte growth factor (KGF), tumor necrosis factor alpha (TNFa), tumor necrosis factor (TNF)- related apoptosis inducing ligand (TRAIL), wnt family member 1 (WNT1), wnt family member 2 (WNT2), wnt family member 2B (WNT2B), wnt family member 3 (WNT3), wnt family member 3 A (WNT3 A), wnt family member 4 (WNT4), wnt family member 5 A (WNT5 A), wnt f amily memb er 5 B (WNT 5 B), wnt f amily m emb er 6 (WNT6), wnt f amily memb er 7 A (WNT7 A), wnt family member 7B (WNT7B), wnt family member 8 A (WNT8 A), wnt family member 8B (WNT8B), wnt family member 9A (WNT9A), wnt family member 9B (WNT9B), wnt family member 1 OA (WNT10 A), wnt family member 1 OB (WNT 1 OB), wnt family member 11 (WNT11), or wnt family member 16 (WNT 16), or a mature peptide or functional portion thereof.

[0135] In some embodiments, the mammalian growth factor is a human growth factor. Nonlimiting examples of human growth factors and mature peptides and / or functional portions thereof are provided in Table 1. In some embodiments, the mammalian growth factor comprises a sequence that is at least 70% identical (e.g., at least 75% identical, at least 80% identical, at least 85% identical, at least 90% identical, at least 95% identical, or at least 99% identical) to any of the sequences in Table 1 or any secreted human growth factor, and has osteogenic activity. In some embodiments, the amino acids in a mammalian growth factor that are conserved between different species are likely important for osteogenic activity and may not be mutated, while amino acids in a mammalian growth factor that are not conserved between different species are notlikely important for osteogenic activity and may be mutated.

[0136] In some embodiments, the mammalian growth factor comprises BMP -2. In some embodiments, the mammaliangrowthfactoris a mature peptideof BMP-2 (e.g., does not comprise a signal sequence). In some embodiments, the mammalian growth factor comprises a functional portion of BMP-2. In some embodiments, the functional portion of BMP-2 comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to : QAKHKQRKRLKSSCKRHPLYVDFSDVGWNDWIVAPPGYHAFYCHGECPFPLADHLNS TNHAIVQTLVNSVNSKIPKACCVPTELSAISMLYLDENEKVVLKNYQDMVVEGCGCR (SEQ ID NO: 454). In some embodiments, the mammalian growth factor comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 454. In some embodiments, the mammalian growth factor comprises a sequence at least about 90% identical to SEQ ID NO: 454. In some embodiments, the mammalian growth factor comprises SEQ ID NO: 454.

[0137] In some embodiments, the mammalian growth factor is a non-human mammalian growth factor. The non-human mammalian growth factor may be homologous to a human growth factor, such as one or more of the human growth factors of Table 1 . In some embodiments, a non-human mammalian growth factor is homologous to a human growth factor if the non-human mammalian growth factor is at least about 80% identical to the human mammalian growth factor as determined using the NCBI Blast alignment algorithm as of the date of this filing. In some cases, the coverage is at least about 90%. In some embodiments, a non-human mammalian growth factor is homologous to a human growth factor if the non-human mammalian growth factor is atleast about 80% positive as compared to the human mammalian growth factor as determined using the NCBI Blast alignment algorithm as of the date of this filing. In some cases, the coverage is at least about 90%. In some embodiments, a non-human mammalian growth factor is homologous to a human growth factor if the non-human mammalian growth factor aligned with the human growth factor using the NCBI Blast as of the date of this filing has an E value of less than about IE-40, at least about IE-50, IE-60, IE-70, or IE-10, with a query cover of at least about 90%.

[0138] Table 1. Therapeutic Growth Factors

[0139] Targeting moieties In some embodiments, the device or kit comprises a targeting moiety that tethers the therapeutic agent to the structure. In some embodiments, the targeting moiety is connected to the therapeutic agent, and the moiety non-covalently binds to the structure. As a non-limiting example, the targeting moiety is covalently connected to the therapeutic agent via a peptide bond. For instance, targeting moiety comprises a targeting peptide, and the targeting peptide is linked to the therapeutic agent via a peptide bond.

[0140] In some embodiments, the targeting moiety has an affinity for the structure, or a component of the structure, e.g., to a ceramic material of the structure such as calcium phosphate. In some embodiments, the dissociation constant (KD) for binding between the targeting moiety and the structure or component thereof is: (i) at least about 1 fM, at least about 10 fM, at least about 100 fM, or at least about 1 pM; and (ii) less than about 100 pM, less than about 90 pM, less than about 80 pM, less than about 70 pM, less than about 60 pM, less than about 50 pM, less than about 40 pM, less than about 30 pM, less than about 20 pM, less than about 10 pM, less than about 5 pM, less than about 1 pM, or less than about 100 pM. For example, the targeting moiety may bind to beta -tricalcium phosphate with an affinity of about 100 f to about 100 pM, about 1 pM to about 100 pM, about 10 pMto about 100 pM, about 100 pMto about 100 pM, or about 1 pM to about 100 pM.

[0141] In some embodiments, the targeting moiety comprises one or more targeting peptides that each bind to the structure. In some embodiments, the targeting peptide binds to the ceramic material of the structure. For example, the targeting peptide binds to calcium phosphate (e.g., tricalcium phosphate, beta tricalcium phosphate, alpha tricalcium phosphate), hydroxyapatite, fluorapatite, bone (e.g., demineralized bone), glasses (bioglasses) such as silicates, vanadates, and related ceramic minerals, or chelated divalent metal ions, or a combination thereof. In some embodiments, the targeting peptide comprises two or more targeting peptides. In some embodiments, two or more targeting peptides is no more than about 50, 45, 40, 35, 30, 25, 20, 15, or 10 targeting peptides. In some embodiments, two or more targeting peptides is about 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, or 30 targeting peptides. In some embodiments, two or more targeting peptides is about 2 to about 10 targeting peptides. In some embodiments, two or more targeting peptides is about 5 targeting peptides.

[0142] In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 1. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 2. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 3. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 4. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 5. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 6. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 7. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 8. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 9. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 10. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 11. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 12. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 13. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 14. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 15. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 16. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 17. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 18. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 19. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 20. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 21. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 22. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 23. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 24. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 25. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 26. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 27. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 28. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 29. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 30. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 31. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 32. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 33. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 34. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 35. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 36. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 37. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 38. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 39. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 40. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 41. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 42. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 43. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 44. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 45. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 46. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 47. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 48. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 49. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 50. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 51. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 52. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 53. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 54. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 55. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 56. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 57. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 58. In some embodiments, the targeting peptide comprises a sequence atleast about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 59. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 60. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 61.

[0143] Table 2. Targeting Peptides

[0144]

[0145] In some embodiments, a targeting peptide comprises one or more sequences of Table 2. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to a sequence of Table 2.

[0146] Table 3. Additional Targeting Peptides

[0147] In some embodiments, a targeting peptide comprises one or more sequences of Table 3. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to a sequence of Table 3.

[0148] Additional targeting peptides useful in the present disclosure include any one of SEQ ID NO: 1 to SEQ ID NO: 558 of US 7,572,766. In some embodiments, the targeting peptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to any one of SEQ ID NO: 1 to SEQ ID NO: 558 of US 7,572,766.

[0149] In some embodiments, the device or kit comprises a chimeric polypeptide comprising the targeting peptide and a targeting moiety. In some cases, the chimeric polypeptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 433 (ASGAGGSEGGGSEGGTSGATGAGTSTSGGGASTGGGTGQAKHKQRKRLKSSCKRHPL YVDFSDVGWNDWIVAPPGYHAFYCHGECPFPLADHLNSTNHAIVQTLVNSVNSKIPKA CCVPTELSAISMLYLDENEKVVLKNYQDMVVEGCGCR). In some cases, the chimeric polypeptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 434

[0150] (MPIGSLLADTTHHRPWTVIGESTHHRPWSIIGESSHHKPFTGLGDTTHHRPWGILAESTH HKPWTASGAGGSEGGGSEGGTSGATGAGTSTSGGGASTGGGTGQAKHKQRKRLKSSC KRHPLYVDFSDVGWNDWIVAPPGYHAFYCHGECPFPLADHLNSTNHAIVQTLVNSVNS KIPKACCVPTELSAISMLYLDENEKVVLKNYQDMVVEGCGCR). In some cases, the chimeric polypeptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 435

[0151] (LLADTTHHRPWTVIGESTHHRPWSIIGESSHHKPFTGLGDTTHHRPWGILAESTHHKPW TASGAGGSEGGGSEGGTSGATGAGTSTSGGGASTGGGTGQAKHKQRKRLKSSCKRHPL YVDFSDVGWNDWIVAPPGYHAFYCHGECPFPLADHLNSTNHAIVQTLVNSVNSKIPKA CCVPTELSAISMLYLDENEKVVLKNYQDMVVEGCGCR). In some cases, the chimeric polypeptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 436

[0152] (VIGESTHHRPWSIIGESSHHKPFTGLGDTTHHRPWGILAESTHHKPWTASGAGGSEGGG SEGGTSGATGAGTSTSGGGASTGGGTGQAKHKQRKRLKSSCKRHPLYVDFSDVGWND WIVAPPGYHAFYCHGECPFPLADHLNSTNHAIVQTLVNSVNSKIPKACCVPTELSAISML YLDENEKVVLKNYQDMVVEGCGCR). In some cases, the chimeric polypeptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 437 (IIGESSHHKPFTGLGDTTHHRPWGILAESTHHKPWTASGAGGSEGGGSEGGTSGATGA GTSTSGGGASTGGGTGQAKHKQRKRLKSSCKRHPLYVDFSDVGWNDWIVAPPGYHAF YCHGECPFPLADHLNSTNHAIVQTLVNSVNSKIPKACCVPTELSAISMLYLDENEKVVL KNYQDMVVEGCGCR). In some cases, the chimeric polypeptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 438 (GLGDTTHHRPWGILAESTHHKPWTASGAGGSEGGGSEGGTSGATGAGTSTSGGGAST GGGTGQAKHKQRKRLKSSCKRHPLYVDFSDVGWNDWIVAPPGYHAFYCHGECPFPLA DHLNSTNHAIVQTLVNSVNSKIPKACCVPTELSAISMLYLDENEKVVLKNYQDMVVEG CGCR). In some cases, the chimeric polypeptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 439

[0153] (ILAESTHHKPWTASGAGGSEGGGSEGGTSGATGAGTSTSGGGASTGGGTGQAKHKQR KRLKSSCKRHPLYVDFSDVGWNDWIVAPPGYHAFYCHGECPFPLADHLNSTNHAIVQT LVNSVNSKIPKACCVPTELSAISMLYLDENEKVVLKNYQDMVVEGCGCR). In some cases, the chimeric polypeptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 440

[0154] ((X)QAKHKQRKRLKSSCKRHPLYVDFSDVGWNDWIVAPPGYHAFYCHGECPFPLADHL NSTNHAIVQTLVNSVNSKIPKACCVPTELSAISMLYLDENEKVVLKNYQDMVVEGCGC R), wherein X comprises a targeting peptide and optionally a linker. For example, the targeting peptide comprises one or more of SEQ ID NOS: 1-41 . In some cases, the chimeric polypeptide comprises a sequence at least about 70%, 75%, 80%, 85%, 90%, 95%, or 100% identical to SEQ ID NO: 441

[0155] ((X)ASGAGGSEGGGSEGGTSGATGAGTSTSGGGASTGGGTGQAKHKQRKRLKSSCKRH PLYVDFSDVGWNDWIVAPPGYHAFYCHGECPFPLADHLNSTNHAIVQTLVNSVNSKIP KACCVPTELSAISMLYLDENEKVVLKNYQDMVVEGCGCR), wherein X comprises a targeting peptide and optionally a linker. For example, the targeting peptide comprises one or more of SEQ ID NOS: 1-41.

[0156] In some embodiments, a therapeutic agent is not connected to a structure using a targeting moiety. For example, the therapeutic agentmay interact with the structure via non -covalentbonds. The therapeutic agent may be connected to a structure by hydrogen bonding, ionic bonding hydrophobic interactions, or van der Waals forces. The therapeutic agent may also be connected to a structure using covalentbonds. Examples of methods for connecting using covalentbonds includes chemical linkers and spacers that are used for modifying active groups within proteins such as amines, thiols and carbohydrates.

[0157] In some embodiments, provided is a device comprising a structure thatis seeded with cells. Non-limiting examples of cells include osteocytes and other bone cells, chondrocytes, and meniscal cells. In some instances, the cells can be added to the completed implantable structures. Device manufacture

[0158] Further provided herein are methods of manufacturing a device comprising a structure (e.g., scaffold) and a therapeutic agent. Some methods comprise: (a) providing a first solution of a therapeutic agent (e.g., a chimeric polypeptide comprising the therapeutic agent and a targeting moiety), (b) providing a structure, and (c) combining (a) and (b). In some embodiments, the method further comprises (d) washing the structure of step (c) with a second solution, such as phosphate buffered saline (PBS). In some embodiments, the method further comprises drying the structure of step (c) or step (d).

[0159] In some embodiments, the mass of the therapeutic agent (e.g., a therapeutic agent alone or a therapeutic agent connected to a targeting moiety) per cubic centimeter of the structure in a device is between about 0.05 and 50 (mg / cc), e.g., about 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1 , 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 15, 20, 25, 30, 35, 40, 45, or 50 mg / cc or any number therebetween . For example, the therapeutic agent is about 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2 mg per cubic centimeter device. One method of measuring the amount of therapeutic peptide bound to the structure includes: (1) measuring the mass of therapeutic peptide input in the first solution, (2) measuring the mass of the therapeutic agent remaining in the first solution after combination with and removal from the structure, (3) measuring the mass of the therapeutic agent in the second solution if a wash step is included, (4) summing (2) and (3); and subtracting the sum of (4) from (1).

[0160] Non-limiting numbered embodiments

[0161] 1 . A composition comprising a therapeutic living bioreactor, wherein the therapeutic living bioreactor comprises a three-dimensional structure and a therapeutic agent optionally bound to the three-dimensional structure.

[0162] 2. The composition of embodiment 1, wherein the three-dimensional structure comprises a three dimensional scaffold.

[0163] 3. The composition of embodiment 2, wherein the three-dimensional scaffold comprises a plurality of biodegradable fibers, a 3D printed structure, or a combination thereof.

[0164] 4. The composition of embodiment 3, wherein the plurality of biodegradable fibers comprise electrospun biodegradable fibers.

[0165] 5. The composition of embodiment 3, wherein the biodegradable fibers and / or the 3D printed structure comprises calcium phosphate, hydroxyapatite, fluorapatite, bone, glasses, chelated divalent metal ions, or a combination thereof.

[0166] 6. The composition of embodiment 5, wherein the calcium phosphate comprises tricalcium phosphate, beta tricalcium phosphate, alpha tricalcium phosphate, or a combination thereof. 7. The composition of embodiment 5, wherein the bone comprises demineralized bone.

[0167] 8. The composition of embodiment 5, wherein the glasses comprises bioglasses.

[0168] 9. The composition of embodiment 5, wherein the bioglasses comprise silicates, vanadates, or a combination thereof.

[0169] 10. The composition of embodiment 1 , wherein the therapeutic agent comprises a growth factor, a bone material, a graft, a cell therapy agent, or a combination thereof.

[0170] 11. The composition of embodiment 10, wherein the growth factor comprises epidermal growth factor (EGF), platelet derived growth factor (PDGF), insulin like growth factor (IGF-1), fibroblast growth factor (FGF), fibroblast growth factor 2 (FGF2), fibroblast growth factor 18 (FGF18), transforming growth factor alpha (TGF-a), transforming growth factor beta (TGF-P), transforming growth factor beta 1 (TGF-pi), transforming growth factor beta 3 (TGF-P3), osteogenic protein 1 (OP-1), osteogenic protein 2 (OP-2), osteogenic protein 3 (OP-3), bone morphogenetic protein 2 (BMP-2), bone morphogenetic protein 3 (BMP-3), bone morphogenetic protein 4 (BMP-4), bone morphogenetic protein 5 (BMP-5), bone morphogenetic protein 6 (BMP-6), bone morphogenetic protein 7 (BMP-7), bone morphogenetic protein (BMP-9), bone morphogenetic protein 10 (BMP-10), bone morphogenetic protein 11 (BMP-11), bone morphogenetic protein 12 (BMP-12), bone morphogenetic protein 13 (BMP-13), bone morphogenetic protein 15 (BMP-15), delta-like ligand-4 (DLL4), dentin phosphoprotein (DPP), vegetal related growth factor (Vgr), growth differentiation factor 1 (GDF-1), growth differentiation factor 3 (GDF-3), growth differentiation factor 5 (GDF-5), growth differentiation factor 6 (GDF-6), growth differentiation factor 7 (GDF-7), growth differentiation factor 8 (GDF8), growth differentiation factor 11 (GDF11), growth differentiation factor 15 (GDF15), vascular endothelial growth factor (VEGF), hyaluronic acid binding protein (HABP), and collagen binding protein (CBP), fibroblast growth factor 18 (FGF-18), keratinocyte growth factor (KGF), tumor necrosis factor alpha (TNFa), tumor necrosis factor (TNF)- related apoptosis inducing ligand (TRAIL), wnt family member 1 (WNT1), wnt family member 2 (WNT2), wnt family member 2B (WNT2B), wnt family member 3 (WNT3), wnt family member 3 A (WNT3 A), wnt family member 4 (WNT4), wnt family member 5 A (WNT5A), wnt family member 5B (WNT5B), wnt family member 6 (WNT6), wnt family member 7A (WNT7A), wnt family member 7B (WNT7B), wnt family member 8A (WNT8A), wnt family member 8B (WNT8B), wnt family member 9 A (WNT9A), wnt family member 9B (WNT9B), wnt family member 10A (WNT10A), wnt family member 10B (WNT10B), wnt family member 11 (WNT11), or wnt family member 16 (WNT16), or a mature peptide or functional portion thereof.

[0171] 12. The composition of embodiment 10, wherein the cell therapy agent comprises a protein therapeutic agent, an enzyme replacement therapy agent, a metabolic cell therapy agent, an antibody, a diagnostic protein agent, a protein contrast agent, a secondary metabolite agent, a an autograft, an allograft, cells that sense and respond to stimuli, or a combination thereof.

[0172] 13. The composition of embodiment 1, wherein the therapeutic agent further comprises a binding peptide.

[0173] 14. The composition of embodiment 13, wherein the binding peptide comprises a peptide of Table 2 or Table 3.

[0174] 15. The composition of any one of the preceding embodiments, wherein the living bioreactor provides a cell niche that results in increased differentiation of cells within the cell niche, increased release of a cell therapy agent, and / or increased therapeutic delivery of a cell therapy agent, as compared to a cell niche that does not comprise the living bioreactor.

[0175] 16. The composition of embodiment 15, wherein the cell niche is in vivo, or in vitro.

[0176] 17. The composition of embodiment 15, wherein the cell niche is within a subject.

[0177] 18. The composition of embodiment 16, wherein the subject is a mammal.

[0178] 19. The composition of embodiment 18, wherein the mammal is a human.

[0179] 20. A cell therapy method, wherein the method comprises administering the composition of any one of embodiments 1-19 to a subject.

[0180] 21. The method of embodiment 20, wherein the cell therapy comprises enzyme replacement therapy, metabolic cell therapy, therapeutic delivery, cell or tissue generation or regeneration therapy, or a combination thereof.

[0181] 22. The method of embodiment 21, wherein the cell or tissue generation or regeneration therapy induces the generation or regeneration of lymphocytes.

[0182] 23. The method of embodiment 21 , wherein the cell or tissue generation or regeneration therapy induces bone marrow formation.

[0183] 24. The method of embodiment 21, wherein the cell or tissue generation or regeneration therapy induces T cell formation.

[0184] 25. The method of embodiment 22, wherein the generation or regeneration of lymphocytes is increased in a subject administered the composition of any one of embodiments 1-19 as compared to a subject who has not been administered the composition of any one of embodiments 1-19. 26. The method of embodiment 21, wherein the enzyme replacement therapy comprises one or more enzymes that are deficient or absent from the human body.

[0185] 27. The method of embodiment 21, wherein the metabolic cell therapy comprises peptides, proteins, or secondary metabolites that treat a metabolic condition.

[0186] 28. The method of embodiment 21, wherein the therapeutic delivery comprises any peptide or protein that exhibits a biological effect in the human body.

[0187] The terminology used herein is for the purpose of describing particular cases only and is not intended to be limiting. The singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. To the extent that the terms “including”, “includes”, “having”, “has”, “with”, or variants thereof are usedin either the detailed description and / or the claims, such terms are intended to be inclusive in a manner similar to the term “comprising.”

[0188] In some embodiments, the term “about” or “approximately” means within an acceptable error range for the particular value as determined by one of ordinary skill in the art, which will depend in part on how the value is measured or determined, e.g., the limitations of the measurement system. For example, “about” can mean within 1 or more than 1 standard deviation, per the practice in the given value.

[0189] The term “subject” as used herein refers to any mammal. A subject therefore refers to, for example, mice, rats, dogs, cats, horses, cows, pigs, guinea pigs, rats, humans, monkeys, and the like. When the subject is a human, the subject may be referred to herein as a patient. In some embodiments, the subject or “subject in need of treatment” may be a canine {e.g., a dog), feline {e.g., a cat), equine {e.g., a horse), ovine, bovine, porcine, caprine, primate, e.g., a simian {e.g., a monkey {e.g., marmoset, baboon), or an ape {e.g., a gorilla, chimpanzee, orangutan, or gibbon), a human, or a rodent (e.g., a mouse, a guinea pig, a hamster, or a rat). In some embodiments, the subject or “subject in need of treatment” may be a non -human mammal, especially mammals that are conventionally usedas models for demonstratingtherapeutic efficacy in humans {e.g., murine, lapine, porcine, canine, or primate animals) may be employed.

[0190] In some embodiments, the term “therapeutically effective amount” refers to an amount of a polypeptide or composition effective to “treat” a disease, condition or disorder in a subject. In some cases, therapeutically effective amount of the polypeptide or composition reduces the severity of symptoms of the disease, condition or disorder. In some instances, the disease, condition or disorder comprises a defect in an organ or tissue. In some embodiments, “affinity” refers to the strength of the sum total of non-covalent interactions between a P-TCP binding sequence (or a chimeric polypeptide or polypeptide comprising a P-TCP binding sequence) and its binding partner (e.g., P-TCP). Affinity can be measured by common methods known in the art, including those described herein. Affinity can be determined, for example, using surface plasmon resonance (SPR) technology (e.g., BIACORE®) or biolayer interferometry (e.g., FORTEBIO®).

[0191] Percent (%) sequence identity with respect to a reference polypeptide sequence is the percentage of amino acid residues in a candidate sequence that are identical with the amino acid residues in the reference polypeptide sequence, after aligning the sequences and introducing gaps, if necessary, to achieve the maximum percent sequence identity, and not considering any conservative substitutions as part of the sequence identity. Alignment for purposes of determining percent amino acid sequence identity can be achieved in various way s that are known for instance, using publicly available computer software such as BLAST, BLAST -2, ALIGN or Megalign (DNASTAR) software. Appropriate parameters for aligning sequences are able to be determined, including algorithms needed to achieve maximal alignment over the full length of the sequences being compared. For purposes herein, however, % amino acid sequence identity values are generated using the sequence comparison computer program ALIGN -2. The ALIGN-2 sequence comparison computer program was authored by Genentech, Inc., and the source code has been filed with user documentation in the U.S. Copyright Office, Washington D.C., 20559, where it is registered under U.S. CopyrightRegistration No. TXU510087. The ALIGN-2 program is publicly available from Genentech, Inc., South San Francisco, Calif., or may be compiled from the source code. The ALIGN-2 program should be compiled for use on a UNIX operating system, including digital UNIX V4.0D. All sequence comparison parameters are set by the ALIGN-2 program and do not vary.

[0192] In situations where ALIGN-2 is employed for amino acid sequence comparisons, the % amino acid sequence identity of a given amino acid sequence A to, with, or against a given amino acid sequence B (which can alternatively be phrased as a given amino acid sequence A that has or comprises a certain % amino acid sequence identity to, with, or against a given amino acid sequence B) is calculated as follows: 100 times the fraction X / Y, where X is the number of amino acid residues scored as identical matches by the sequence alignment program ALIGN-2 in that program's alignment of A and B, and where Y is the total number of amino acid residues in B. It will be appreciated that where the length of amino acid sequence A is not equal to the length of amino acid sequence B, the % amino acid sequence identity of A to B will not equal the % amino acid sequence identity of B to A. Unless specifically stated otherwise, all % amino acid sequence identity values used herein are obtained as described in the immediately preceding paragraph using the ALIGN-2 computer program.

[0193] Each of the embodiments described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the present invention. Any recited method can be carried out in the order of events recited or in any other order which is logically possible.

[0194] A number of embodiments of the disclosure have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. Additionally, while specific formulations for the inks are described, variations of the specific quantities of each ink ingredient are possible. Accordingly, other embodiments are within the scope of the following claims.

[0195] EXAMPLES

[0196] Example 1: Ink Formulations and 3D Printed Scaffolds

[0197] Ink formulation and scaffold #1 :

[0198] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains two sacrificial pore formers (water soluble polyethylene glycol and water soluble sucrose) to expose more P-TCP surface area for tBMP2 binding. This ink is a low viscosity formulation that was extruded through a 400 pm diameter nozzle on an Allevi 3 pneumatic bioprinter. After 3D printing was complete, the resulting scaffold was soaked in water to dissolve the sacrificial polyethylene glycol and sucrose pore formers. The resulting scaffold #1 contains 75% by weight P-TCP powder, and 25% by weight poly caprolactone.

[0199] This ink is also converted into a filament form and utilized to prepare a 3D printed scaffold using a fused filament fabrication (FFF or FDM) 3D printer. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol and sucrose pore formers. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight poly caprolactone.

[0200] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0201] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method. Table 4. Example ink formulation #1

[0202] Ink formulation #2

[0203] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. This formulation employs a 95mol% caprolactone 5mol% glycolide copolymer for faster bioresorption characteristics compared to poly caprolactone. This ink is a low viscosity formulation that was extruded through a 320 pm diameter nozzle on an Allevi 3 pneumatic bioprinter. After 3D printing is complete, the resulting scaffold was soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold #2 contains 75% by weight P-TCP powder, and 25% by weight caprolactone / glycolide copolymer (95 :5).

[0204] This ink is also converted into a filament form and utilized to prepare a 3D printed scaffold using a fused filament fabrication (FFF or FDM) 3D printer. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight caprolactone / glycolide copolymer (95:5).

[0205] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0206] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method. Table 5. Example ink formulation #2

[0207] Ink formulation #3

[0208] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. This formulation employs a 90mol% caprolactone 10mol% glycolide copolymer for fast bioresorption characteristics compared to poly caprolactone. This ink is a low viscosity formulation that was extruded through a 320 pm diameter nozzle on an Allevi 3 pneumatic bioprinter. After 3D printing was complete, the resulting scaffold was soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold #3 contains 75% by weight P-TCP powder, and 25% by weight caprolactone / glycolide copolymer (90: 10).

[0209] This ink is also converted into a filament form and utilized to prepare a 3D printed scaffold using a fused filament fabrication (FFF or FDM) 3D printer. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight caprolactone / glycolide copolymer (90: 10).

[0210] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0211] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method. Table 6. Example ink formulation #3

[0212] Ink formulation #4

[0213] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. This formulation employs a 50mol%:50mol% poly(D,L-lactide-co-glycolide) copolymer for fast bioresorption characteristics compared to poly caprolactone. This ink is a low viscosity formulation that was extruded through a 400 pm diameter nozzle on an Allevi 3 pneumatic bioprinter. After 3D printing was complete, the resulting scaffold was soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold #4 contains 75% by weight P-TCP powder, and 25% by weight poly(D,L-lactide-co-glycolide) copolymer (50:50).

[0214] This ink is also converted into a filament form and utilized to prepare a 3D printed scaffold using a fused filament fabrication (FFF or FDM) 3D printer. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight poly(D,L- lactide-co-glycolide) copolymer (50:50).

[0215] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0216] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method. Table 7. Example ink formulation #4

[0217] Ink formulation #5

[0218] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that was formed into a 1.75 mm filament for 3D printing on a RepRap style FFF 3D printers (e.g. Prusa i3 MK3 S 3D printer) with a 400 pm diameter nozzle. The higher molecular weight polyethylene glycol (8000 MW for FFF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material which aids in extrusion of 1.75 mm diameter filaments. After 3D printing was complete, the resulting scaffold was soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold #5 contains 75% by weight P-TCP powder, and 25% by weight poly caprolactone.

[0219] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0220] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0221] Table 8. Example ink formulation #5

[0222] Ink formulation #6

[0223] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. This ink also contains a blowing agent (sodium bicarbonate) which thermally decomposes and releases CO2 gas during 3D printing to create a foamed structure, thus increasing the porosity of the 3D printed scaffold. This ink is a moderate viscosity formulation that was formed into a 1.75 mm filament for 3D printing on a RepRap style FFF 3D printers (e.g. Prusa i3 MK3S 3D printer) with a 400 pm diameter nozzle. The higher molecular weight polyethylene glycol (8000 MW for FFF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material which aids in extrusion of 1.75 mm diameter filaments. After 3D printing was complete, the resulting scaffold was soaked in water to dissolve the sacrificial polyethylene glycol pore former and sodium carbonate by -product from the sodium bicarbonate thermal decomposition. The resulting scaffold #6 contains 75% by weight P-TCP powder, and 25% by weight poly caprolactone.

[0224] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0225] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0226] Table 9. Example ink formulation #6

[0227] Ink formulation #7

[0228] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. This formulation employs a 90mol% :10mol% poly(dioxanone-co-L-lactide) copolymer for faster bioresorption characteristics compared to poly caprolactone. This ink is a low viscosity formulation that can be extruded through a 400 pm diameter nozzle on an Allevi 3 pneumatic bioprinter. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight dioxanone / L-lactide copolymer (90:10).

[0229] This ink is also converted into a filament form and utilized to prepare a 3D printed scaffold using a fused filament fabrication (FFF or FDM) 3D printer. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight dioxanone / L- lactide copolymer (90:10).

[0230] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0231] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0232] Table 10. Example ink formulation #7

[0233] Ink formulation #8

[0234] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into a 1.75 mm filament for 3D printing on a RepRap style FFF 3D printers (e.g. Prusa i3 MK3 S 3D printer) with a 400 pm diameter nozzle. The higher molecular weight blend of polyethylene glycol (8000 MW and 20000 MW for FFF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material which aids in extrusion of 1 .75 mm diameter filaments. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight poly caprolactone.

[0235] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0236] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0237] Table 11. Example ink formulation #8

[0238] Ink formulation #9

[0239] This 3D printing ink material is a flexible, polymer-ceramic composite material containing

[0240] P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains two sacrificial pore formers (water soluble polyethylene glycol and water soluble glucose) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into a 1.75 mm filament for 3D printing on a RepRap style FFF 3D printers (e.g. Prusa i3 MK3 S 3D printer) with a 400 pm diameter nozzle. The higher molecular weight blend of polyethylene glycol (8000 MW and 20000 MW for FFF 3D printing vs. 1500 MW for syringe based bioprinting) results in a higher viscosity material, which aids in extrusion of 1.75 mm diameter filaments. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol and sucrose pore formers. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight polycaprolactone.

[0241] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0242] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0243] Table 12. Example ink formulation #9

[0244] Ink formulation #10

[0245] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tether to a therapeutic agent, such a tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. This formulation employs a 95mol% caprolactone 5mol% glycolide copolymer for faster bioresorption characteristics compared to polycaprolactone. This ink is a moderate viscosity formulation that can be formed into a 1 .75 mm filament for 3D printing on a RepRap styleFFF 3D printers (e.g. Prusa i3 MK3 S 3D printer)with a400 pm diameternozzle. The higher molecular weight blend of polyethylene glycol (8000 MW and 20000 MW forFFF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material which aids in extrusion of 1 .75 mm diameter filaments. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight caprolactone / glycolide copolymer (95:5).

[0246] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0247] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0248] Table 13. Example ink formulation #10

[0249] Ink formulation #11

[0250] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tether to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. This formulation employs a 90mol% caprolactone 10mol% glycolide copolymer for fast bioresorption characteristics compared to polycaprolactone. This ink is a moderate viscosity formulation that can be formed into a 1.75 mm filament for 3D printing on a RepRap styleFFF 3D printers (e.g. Prusai3 MK3 S 3D printer)with a400 pm diameter nozzle. The higher molecular weight blend of polyethylene glycol (8000 MW and 20000 MW forFFF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material which aids in extrusion of 1 .75 mm diameter filaments. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight caprolactone / glycolide copolymer (90: 10).

[0251] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0252] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0253] Table 14. Example ink formulation #11

[0254] Ink formulation #12

[0255] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. This formulation employs a 50mol%:50mol% poly(D,L-lactide-co-glycolide) copolymer for fast bioresorption characteristics compared to polycaprolactone. This ink is a moderate viscosity formulation that can be formed into a 1.75 mm filament for 3D printing on a RepRap style FFF 3D printers (e.g. Prusa i3 MK3 S 3D printer) with a 400 pm diameter nozzle. The higher molecular weight blend of polyethylene glycol (8000 MW and 20000 MW for FFF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material which aids in extrusion of 1.75 mm diameter filaments. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight poly(D,L-lactide- co-glycolide) copolymer (50:50). This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0256] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0257] Table 15. Example ink formulation #12

[0258] Ink formulation #13

[0259] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. 3D printing is performed using the formulation in a syringe ink and filament form. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains P-TCP and PDS.

[0260] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0261] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0262] Table 16. Example ink formulation #13 Ink formulation #14

[0263] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. 3D printing is performed using the formulation in a syringe ink and filament form. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains P-TCP and PDS-glycolide copolymer (90:10).

[0264] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0265] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0266] Table 17. Example ink formulation #14

[0267] Ink formulation #15

[0268] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains a sacrificial pore former (water soluble polyethylene glycol) to expose more P-TCP surface area for agent binding. 3D printing is performed using the formulation in a syringe ink and filament form. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore former. The resulting scaffold contains P-TCP and -L-Lactide Copolymer (90:10).

[0269] This ink is also converted into pellets (e.g., a filament is formed into small pellets) and fed from a hopper into a mini-screw extrusion head which melts and pushes the material out of a fine nozzle.

[0270] This ink is also cryomilled into a fine powder. A laser heats the powder into the desired configuration using the SLS method.

[0271] Table 18. Example ink formulation #15 Ink formulation #16

[0272] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains sacrificial pore formers (water soluble polyethylene glycol components) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into ~3-4mm diameter pellets to be used as feedstockin a fused granular fabrication (FGF) 3D printer (e.g. Piocreat G5) with a 300 - 1,000 pm diameter nozzle. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethyleneglycol pore former. The higher molecular weight blend of polyethylene glycol (8000 MW and 35000 MW for FGF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethylene glycol pore formers. The resulting scaffold contains 75% by weight P-TCP powder, and 25% by weight polycaprolactone. Two example scaffolds were prepared using this ink via FGF 3D printing. Images of the scaffolds are shown in FIGS. 13A-13D, and FIGS. 14A-14D.

[0273] This ink is prepared in pellet or filament form for FGF orFFF printing, respectively. This ink is cryomilled into a fine powder, e.g., for SLS printing.

[0274] Table 19. Example ink formulation #16 - new pellet formulation

[0275] Ink formulation #17

[0276] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains sacrificial pore formers (water soluble polyethylene glycol components) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into ~3-4mm diameter pellets to be used as feedstockin a fused granular fabrication (FGF) 3D printer (e.g. Piocreat G5) with a 300 - 1,000 pm diameter nozzle. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethyleneglycol pore former. The higher molecular weight blend of polyethylene glycol (8000 MW and 35000 MW for FGF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial PEG and sucrose. The resulting scaffold contains 50-88% by weight P -TCP powder, and 13-50% by weight poly caprolactone.

[0277] This ink is prepared in pellet or filament form for FGF orFFF printing, respectively. This ink is cryomilled into a fine powder, e.g., for SLS printing.

[0278] Table 20. Example ink formulation #17

[0279] Ink formulation #18

[0280] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains sacrificial pore formers (water soluble polyethylene glycol components) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into ~2-4mm diameter pellets to be used as feedstock in a fused granular fabrication (FGF) 3D printer (e.g. Piocreat G5) with a 300 - 1,000 pm diameter nozzle. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethyleneglycol pore former. The higher molecular weight blend of polyethylene glycol (8000 MW and 35000 MW for FGF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial PEG. The resulting scaffold contains 55-88% by weight P-TCP powder, and 13-50% by weight Caprolactone / Glycolide copolymer (95 :5).

[0281] This ink is prepared in pellet or filament form for FGF orFFF printing, respectively. This ink is cryomilled into a fine powder, e.g., for SLS printing. Table 21. Specific Ink Formulation #18

[0282] Table 22. Example ink formulation #18 Table 23. Composition of prepared scaffold material after post-processing (soaking and drying) Table 24. General composition ranges for prepared scaffold material after postprocessing

[0283] Ink formulation #19

[0284] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains sacrificial pore formers (water soluble polyethylene glycol components) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into ~2-4mm diameter pellets to be used as feedstock in a fused granular fabrication (FGF) 3D printer (e.g. Piocreat G5) with a 300 - 1,000 pm diameter nozzle. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethyleneglycol pore former. The higher molecular weight blend of polyethylene glycol (8000 MW and 35000 MW for FGF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial PEG. The resulting scaffold contains 55-88% by weight P-TCP powder, and 13-50% by weight Caprolactone / Glycolide copolymer (90:10).

[0285] This ink is prepared in pellet or filament form for FGF orFFF printing, respectively. This ink is cryomilled into a fine powder, e.g., for SLS printing.

[0286] Table 25. Specific Ink Formulation #19

[0287] Table 26. Example ink formulation #19

[0288] Table 27. Composition of prepared scaffold material after post-processing (soaking and drying)

[0289] Table 28. General composition ranges for prepared scaffold material after postprocessing Ink formulation #20

[0290] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains sacrificial pore formers (water soluble polyethylene glycol components) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into ~3-4mm diameter pellets to be used as feedstockin a fused granular fabrication (FGF) 3D printer (e.g. Piocreat G5) with a 300 - 1,000 pm diameter nozzle. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethyleneglycol pore former. The higher molecular weight blend of polyethylene glycol (8000 MW and 35000 MW for FGF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial PEG. The resulting scaffold contains 55-88% by weight P-TCP powder, and 13-50% by weight Poly(D,L-lactide-co-glycolide) copolymer (50:50).

[0291] This ink is prepared in pellet or filament form for FGF orFFF printing, respectively. This ink is cryomilled into a fine powder, e.g., for SLS printing.

[0292] Table 29. Example ink formulation #20

[0293] Ink formulation #21

[0294] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains sacrificial pore formers (water soluble polyethylene glycol components) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into ~3-4mm diameter pellets to be used as feedstockin a fused granular fabrication (FGF) 3D printer (e.g. Piocreat G5) with a 300 - 1,000 pm diameter nozzle. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethyleneglycol pore former. The higher molecular weight blend of polyethylene glycol (8000 MW and 35000 MW for FGF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial PEG. The resulting scaffold contains 55-88% by weight P-TCP powder, and 13-50% by weight PDS.

[0295] This ink is prepared in pellet or filament form for FGF orFFF printing, respectively. This ink is cryomilled into a fine powder, e.g., for SLS printing.

[0296] Table 30. Example ink formulation #21 Ink formulation #22

[0297] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains sacrificial pore formers (water soluble polyethylene glycol components) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into ~3-4mm diameter pellets to be used as feedstockin a fused granular fabrication (FGF) 3D printer (e.g. Piocreat G5) with a 300 - 1,000 pm diameter nozzle. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethyleneglycol pore former. The higher molecular weight blend of polyethylene glycol (8000 MW and 35000 MW for FGF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial PEG. The resulting scaffold contains 55-88% by weight P-TCP powder, and 13-50% by weight Dioxanone / L-lactide copolymer (90:10).

[0298] This ink is prepared in pellet or filament form for FGF orFFF printing, respectively. This ink is cryomilled into a fine powder, e.g., for SLS printing.

[0299] Table 31. Example ink formulation #22

[0300] Ink formulation #23

[0301] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains sacrificial pore formers (water soluble polyethylene glycol components) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into ~3-4mm diameter pellets to be used as feedstockin a fused granular fabrication (FGF) 3D printer (e.g. Piocreat G5) with a 300 - 1,000 pm diameter nozzle. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethyleneglycol pore former. The higher molecular weight blend of polyethylene glycol (8000 MW and 35000 MW for FGF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial PEG. The resulting scaffold contains 55-88% by weight P-TCP powder, and 13-50% by weight Glycolide / L-lactide copolymer (95:5). This ink is prepared in pellet or filament form forFGF orFFF printing, respectively. This ink is cryomilled into a fine powder, e.g., for SLS printing.

[0302] Table 32. Example ink formulation #23

[0303] Ink formulation #24

[0304] This 3D printing ink material is a flexible, polymer-ceramic composite material containing P-TCP that may be tethered to a therapeutic agent, such as tBMP2. This formulation contains sacrificial pore formers (water soluble polyethylene glycol components) to expose more P-TCP surface area for agent binding. This ink is a moderate viscosity formulation that can be formed into ~3-4mm diameter pellets to be used as feedstockin a fused granular fabrication (FGF) 3D printer (e.g. Piocreat G5) with a 300 - 1,000 pm diameter nozzle. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial polyethyleneglycol pore former. The higher molecular weight blend of polyethylene glycol (8000 MW and 35000 MW for FGF 3D printing vs. 1500 MW for syringe-based bioprinting) results in a higher viscosity material. After 3D printing is complete, the resulting scaffold is soaked in water to dissolve the sacrificial PEG. The resulting scaffold contains 55-88% by weight P-TCP powder, and 13-50% by weight Poly-l-lactide.

[0305] This ink is prepared in pellet or filament form forFGF orFFF printing, respectively. This ink is cryomilled into a fine powder, e.g., for SLS printing.

[0306] Table 33. Example ink formulation #24

[0307] Example 2: Ink Preparation and Scaffold Manufacture by 3D Printing

[0308] Ink formulation and scaffold #1

[0309] Method: To make 5.3 cc batch of ink, 5.6 g of P-TCP powder, 1.87 g of poly caprolactone powder, 1.87 g of polyethylene glycol flake and 0.49 g sucrose were added to a glass mixing container. The glass jar was placed in a dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. The mixer was mixed for 5 min at high intensity (3500 rpm). During mixing, the internal friction causes the polycaprolactone and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the P-TCP powder and sucrose powder into the molten polymer blend. The blended ink was allowed to cool for 10-15 min, then mixed for 5 more minutes at 3500 rpm. The mixing / cooling process was repeated for a total of four 5 min mixes at 3500 rpm. After the fourth mix at 3500 rpm, the ink charge was poured out on a glass plate and two spatulas were used to form into a roughly 1 cm diameter x 6 cm long cylinder. While ink was still semi-molten, it was cut into several ~l-2 cm long pieces with straight razor.

[0310] 3D Printing: solidpolymer / p-TCP pieceswere transferred to a 5 cc stainless steel syringe (foruse in Allevi 3 Bioprinter). Extruder CORE printing head was heated to 135°C and allowed to dwell for approximately 30 min to ensure melting of the ink. The ink was printed with 400 micron I.D. conical metallic Luer lock tip using 70 psi pressure and 7 mm / s nozzle velocity. The scaffold was 3D printed on painter’s tape applied to a smooth glass or polymer surface, such as a glass microscope slide, larger glass plate, or 96 well plate lid.

[0311] PostProcessing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol and sucrose from the printed material, thus creating a porous and flexible P-TCP / polycaprolactone composite. Scaffolds were dried for at least twelve hours to ensure residual water has evaporated from the porous scaffold before binding with a therapeutic agent such as tBMP2 protein. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 1A-1C.

[0312] 3D printingis also performedusingaFFF 3Dprinter. Theink#l is extruded into filaments and the filaments are loaded in a FFF 3D printer to generate a 3D printed scaffold. The scaffold is processed using the post processing method outlined above.

[0313] Ink formulation and scaffold #2

[0314] Method: To make a 5 cc batch of ink, 5.6 g of P-TCP powder, 1.87 g of 95 :5 caprolactone / glycolide copolymer pellets, and 1.87 g of polyethylene glycol flake were added to a glass mixing container. The glass jar was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. The mixture was mixed for 5 min at high intensity (3500 rpm). During mixing, the internal friction causes the 95 :5 caprolactone / glycolide copolymer and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the P-TCP powder into the molten polymerblend. The blended ink was allowed to cool for 10-15 min, and then mixed for 5 more minutes at 3500 rpm. The mixing / cooling process was repeated for a total of four 5 min mixes at 3500 rpm. After the fourth mix at 3500 rpm, the ink charge was poured out on a glass plate and two spatulas were used to form into a roughly 1 cm diameter x 6 cm long cylinder. While ink was still semi -molten, it was cut into several ~l-2 cm long pieces with straight razor.

[0315] 3D Printing: The solid polymer / P-TCP pieces were transferred to a 5 cc stainless steel syringe (for use in Allevi 3 Bioprinter). Extruder CORE printing head was heated to 130°C and allowed to dwell for approximately 30 min to ensure melting of the ink. Ink was printed with 320 micron I.D. conical metallic Luer lock tip using 80 psi pressure and 6 mm / s nozzle velocity. Scaffolds were 3D printed on painter’ s tape applied to a smooth glass or polymer surface, such as a glass microscope slide, larger glass plate, or 96 well plate lid.

[0316] PostProcessing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible P-TCP / 95:5 caprolactone / glycolide copolymer composite. The scaffolds were dried for at least twelve hours to ensure residual water evaporated from the porous scaffold before binding with a therapeutic agent like tBMP2. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 2A-2C.

[0317] 3D printingis also performedusingaFFF 3Dprinter. Theink#2 is extruded into filaments and the filaments are loaded in a FFF 3D printer to generate a 3D printed scaffold. The scaffold is processed using the post processing method outlined above.

[0318] Ink formulation and scaffold #3

[0319] Method: To make a 5 cc batch of ink, 5.6 g of P-TCP powder, 1.87 g of 90:10 caprolactone / glycolide copolymer chips, and 1.87 g of polyethylene glycol flake were added to a glass mixing container. The mixture was placed in a glass jar in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. It was then mixed for 5 min at high intensity (3500 rpm). During mixing, the internal friction causes the 90:10 caprolactone / glycolide copolymer and polyethylene glycol to melt, changingthe ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the P-TCP powder into the molten polymer blend. The blended ink was allowed to cool for 10-15 min and then mixed for 5 more minutes at 3500 rpm. The mixing / cooling process was repeated for a total of four 5 min mixes at 3500 rpm. After the fourth mix at 3500 rpm, the ink charge was poured out on a glass plate and two spatulas were used to form into a roughly 1 cm diameter x 6 cm long cylinder. While the ink was still semi-molten, it was cut into several ~l-2 cm long pieces with straight razor.

[0320] 3D Printing: the solid polymer / P-TCP pieces were transferred to a 5 cc stainless steel syringe (for use in Allevi 3 Bioprinter). Extruder CORE printing head was heated to 130°C and allowed to dwell for approximately 30 min to ensure melting of the ink. Ink was printed with 320 micron I.D. conical metallic Luer lock tip using 45 psi pressure and 7 mm / s nozzle velocity. Scaffolds were 3D printed on painter’ s tape applied to a smooth glass or polymer surface, such as a glass microscope slide, larger glass plate, or 96 well plate lid.

[0321] PostProcessing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible P -TCP / 90:10 caprolactone / glycolide copolymer composite. Scaffolds were dried for at least twelve hours to ensure residual water has evaporated from the porous scaffold before binding with a therapeutic agent like tBMP2. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 3A-3C.

[0322] 3D printingis also performedusingaFFF 3Dprinter. Theink#3 is extruded into filaments and the filaments are loaded in a FFF 3D printer to generate a 3D printed scaffold. The scaffold is processed using the post processing method outlined above.

[0323] Ink formulation and scaffold #4

[0324] Method: To make a 2.5 ccbatch of ink, 2.8 g of P-TCP powder, 0.94 g of 50:50 poly(D,L- lactide-co-glycolide) copolymer chunks, and 0.94 g of polyethylene glycol flake were added to a glass mixing container. The glass jar was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. It was mixed for 5 min at high intensity (3500 rpm). During mixing the internal friction causes the 50:50 poly(D,L-lactide-co-glycolide) copolymer and polyethylene glycol to flow, changing the ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the P-TCP powder into the molten polymerblend. The blended ink was allowed to cool for 10-15 min and then mixed for 5 more minutes at 3500 rpm. The mixing / cooling process was repeated for a total of four 5 min mixes at 3500 rpm. After the fourth mix at 3500 rpm, the ink charge was poured out on a glass plate and two spatulas were used to form into a roughly 1 cm diameter x 3 cm long cylinder. While ink was still semi-molten, it was cut into several ~l-2 cm long pieces with straight razor.

[0325] 3D Printing: The solid polymer / P-TCP pieces were transferred to a 5 cc stainless steel syringe (for use in Allevi 3 Bioprinter). Extruder CORE printing head was heated to 85°C and allowed to dwell for approximately 30 min to ensure melting of the ink. Ink was printed with a 400 micron I D. conical metallic Luer lock tip using 60 psi pressure and 7 mm / s nozzle velocity. Scaffolds were 3D printed on painter’ s tape applied to a smooth glass or polymer surface, such as a glass microscope slide, larger glass plate, or 96 well plate lid.

[0326] Post Processing: 3D printed structures are soaked overnight in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible P -TCP / 50:50 poly(D,L-lactide-co-glycolide) composite. Scaffolds were dried for atleasttwelve hours to ensure residual water has evaporated from the porous scaffold before binding with a therapeutic agent like tBMP2. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 4A-4C.

[0327] 3D printingis also performedusingaFFF 3Dprinter. Theink#4 is extruded into filaments and the filaments are loaded in a FFF 3D printer to generate a 3D printed scaffold. The scaffold is processed using the post processing method outlined above.

[0328] Ink formulation and scaffold #5

[0329] Method: To make a 5 cc batch of ink, 5.6 g of P -TCP powder, 1.87 g of poly caprolactone powder, and 1.87 g of polyethylene glycol flake were added to a glass mixing container. The glass jar was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mix at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. It was mixed for 5 min at high intensity (3500 rpm). During mixing, the internal friction causes the poly caprolactone and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the P-TCP powder into the molten polymer blend. The molten ink was poured onto a glass plate and flatten with a spatula to approximately 3 mm thick layer for cooling. After cooling, shears were used to cut into approximately 3 -4 mm pellets. This was repeated for two additional 5 cc batches to create a total 15 cc of pellets for filament extrusion.

[0330] Filament Fabrication: 15 cc of 3 -4 mm pellets were loaded into the hopper of a filament extruder (Filabot EX2 Filament Extruder). A 3x length extended melt filter nozzle (with filter screens removed) with 1.75 mm diameter hole size was used. A cooling fan was placed near the extrusion nozzle to speed up solidification of the extruded filament. The 1.75 mm diameter filament was extruded at extrusion temperature to 62°C and speed at ’A on the analog dial (approximately 1 cm / second extrusion speed). 3D Printing: The 1.75 mm filament was loaded in a Prusa i3 MK3 S 3D printer. This filament material was printed using a 400 micron brass nozzle, 105°C extruder temperature, and 15 mm / s print speed.

[0331] Post Processing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible 0- TCP / poly caprolactone composite. Scaffolds were driedforatleasttwelve hours to ensure residual water has evaporated from the porous scaffold before binding with a therapeutic agent like tBMP2. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 5A- 5C.

[0332] Ink formulation and scaffold #6

[0333] Method: To make a 5.5 cc batch of ink, 5.6 g of P -TCP powder, 1 .87 gof polycaprolactone powder, 1 .87 g of polyethylene glycol flake, and 1.04 g of sodium bicarbonate were added to a glass mixing container. The glass jar was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. It was mixed for 2 min at high intensity (3500 rpm). During mixing the internal friction causes the poly caprolactone and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the P-TCP powder and sodium bicarbonate powder into the molten polymer blend. The molten ink was poured onto a glass plate and flattened with a spatula to approximately 3 mm thick layer for cooling. After cooling, shears were used to cut into approximately 3-4 mm pellets. The was repeated for two additional 5.5 cc batches to create a total 16.5 cc of pellets for filament extrusion.

[0334] Filament Fabrication: 16.5 cc of 3-4 mm pellets were loaded into the hopper of a filament extruder (FilabotEX2 Filament Extruder). A 3x length extended melt filter nozzle (with filter screens removed) with 1.75 mm diameter hole size was used. A cooling fan was placed near the extrusion nozzle to speed up solidification of the extruded filament. The 1.75 mm diameter filament was extruded at extrusion temperature to 62°C and speed at ’A on the analog dial (approximately 1 cm / second extrusion speed).

[0335] 3D Printing: The 1.75 mm filament was loaded in a Prusa i3 MK3 S 3D printer. This filament material was printed using a 400 micron brass nozzle, 155°C extruder temperature, and 15 mm / s print speed.

[0336] PostProcessing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol and sodium carbonate (by-product of the sodium bicarbonate thermal decomposition) from the foamy printed material, thus creating a porous and flexible 0- TCP / poly caprolactone composite. Scaffolds were driedforatleasttwelve hours to ensure residual water has evaporated from the porous scaffold before binding with a therapeutic agent like tBMP2. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 6A- 6C.

[0337] Ink formulation and scaffold #7

[0338] Method: To make a 10 cc batch of ink, 11.2 g of P-TCP powder, 3.74 g of Dioxanone / L- lactide (90: 10) copolymer chips, and 3.74 g of polyethylene glycol flake were added to a glass mixing container. The glass jar was placed in a dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. The glass jar was transferred to a hot plate and heated until it reached 185°C (measured with IR thermometer). Next, the glass jar was immediately transferred back to the dual asymmetric centrifugal mixer and mixed for 5 min at high intensity (3500 rpm). Liquid phase mixing facilitates intimate dispersion of the P-TCP powder into the molten polymer blend. Next, the glass jar was transferred back to the hotplate and the temperature was increased to 185°C. Upon reaching the temperature, the glass jar was immediately transferred back to the dual asymmetric centrifugal mixer and mixed for 5 more minutes at 3500 rpm. The mixing / heating process was repeated for a total of four 5 min mixes at 3500 rpm. After the fourth mix at 3500 rpm, the ink charge was poured out on a glass plate and two spatulas were used to form into a roughly 1 cm diameter x 6 cm long cylinder. While ink was still semi-molten, it was cut into several ~l-2 cm long pieces with straight razor.

[0339] 3D Printing: solidpolymer / p-TCP pieceswere transferred to a 5 cc stainless steel syringe (for use in Allevi 3 Bioprinter). Extruder CORE printing head was heated to 1 10°C and allowed to dwell for approximately 30 min to ensure melting of the ink. The ink was printed with 400 micron I.D. conical metallic Luer lock tip using 15 psi pressure and lO mm / s nozzle velocity. The scaffold was 3D printed on painter’s tape applied to a smooth glass or polymer surface, such as a glass microscope slide, larger glass plate, or 96 well plate lid.

[0340] PostProcessing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol from the printed material. The process created a porous and flexible P- TCP / 90:10 dioxanone-L-lactide copolymer composite. Scaffolds were dried for at least twelve hours to ensure residual water has evaporated from the porous scaffold before binding with a therapeutic agent such as tBMP2 protein. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 7A-7C. 3D printingis also performedusingaFFF 3D printer. Theink#7 is extruded into filaments and the filaments are loaded in a FFF 3D printer to generate a 3D printed scaffold. The scaffold is processed using the post processing method outlined above.

[0341] Ink formulation and scaffold #8

[0342] Method: To make a 16 cc batch of ink, 18 g of P-TCP powder, 6 g of poly caprolactone powder, 3 g of polyethylene glycol (8,000 MW) flake and 3 g of polyethylene glycol (20,000 MW) flake were added to a teflon mixing container. The teflon container was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. Next, the teflon container was mixed for 2.5 min at high intensity (3500 rpm). During mixing, the internal friction causes the poly caprolactone and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the P-TCP powder into the molten polymer blend. The molten ink was poured onto a glass plate and flatten with a spatula to approximately 3 mm thick layer for cooling. It was cooled for 10-15 min. The mixture was returned to the teflon container and mixed for 2.5 more minutes at a high intensity (3500 rpm). The mixing / cooling process was repeated for a total of four 2.5 min mixes at 3500 rpm. After the ink was cooled after the fourth and final mix, shears were used to cut it into approximately 3 -4 mm pellets.

[0343] Filament Fabrication: 16 cc of 3 -4 mm pellets were loaded into the hopper of a filament extruder (Filabot EX2 Filament Extruder). A 3x length extended melt filter nozzle (with filter screens removed) with 1.75 mm diameter hole size was used. A cooling fan was placed near the extrusion nozzle to speed up solidification of the extruded filament. The 1.75 mm diameter filament was extruded at extrusion temperature to 62°C and speed at ’A on the analog dial (approximately 1 cm / second extrusion speed).

[0344] 3D Printing: The 1.75 mm filament was loaded in a Prusa i3 MK3S 3D printer. This filament material was printed using a 400 micron brass nozzle, 105 °C extruder temperature, and 15 mm / s print speed.

[0345] Post Processing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible P- TCP / poly caprolactone composite. Scaffolds were driedforatleasttwelve hours to ensure residual water has evaporated from the porous scaffold before binding with a therapeutic agent li ke tBMP2. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 8A- 8C. Ink formulation and scaffold #9

[0346] Method: To make a 16.3 cc batch of ink, 17.1 g of P-TCP powder, 5.7 g of polycaprolactonepowder, 2.85 gof polyethyleneglycol (8, 000MW) flake, 2.85gof polyethylene glycol (20,000 MW) flake, and 1 .5 g of sucrose were added to a teflon mixing container. The teflon container was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. Next, the teflon container was mixed for 2 min at high intensity (3500 rpm). During mixing, the internal friction causes the polycaprolactone and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the P-TCP powder into the molten polymer blend. The molten ink was poured onto a glass plate and flatten with a spatula to approximately 3 mm thick layer for cooling. It was cooled for 10-15 min. The mixture was returned to the teflon container and mixed for 2 more minutes at a high intensity (3500 rpm). The mixing / cooling process was repeated for a total of four 2 min mixes at 3500 rpm. After the ink was cooled after the fourth and final mix, shears were used to cut it into approximately 3 -4 mm pellets.

[0347] Filament Fabrication: 16.3 cc of 3-4 mm pellets were loaded into the hopper of a filament extruder (Filabot EX2 Filament Extruder). A 3x length extended melt filter nozzle (with filter screens removed) with 1.75 mm diameter hole size wasused. A cooling fan was placed near the extrusion nozzle to speed up solidification of the extruded filament. The 1.75 mm diameter filament was extruded at extrusion temperature to 62°C and speed at ’A on the analog dial (approximately 1 cm / second extrusion speed).

[0348] 3D Printing: The 1.75 mm filament was loaded in a Prusa i3 MK3 S 3D printer. This filament material was printed using a 400 micron brass nozzle, 140°C extruder temperature, and 10 mm / s print speed.

[0349] Post Processing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol and sucrose from the printed material, thus creating a porous and flexible P-TCP / poly caprolactone composite. Scaffolds were dried for at least twelve hours to ensure residual water has evaporated from the porous scaffold before binding with a therapeutic agent like tBMP2. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 9A-9C.

[0350] Ink formulation and scaffold #10

[0351] Method: To make a 16 cc batch of ink, 18 g of P-TCP powder, 6 g of caprolactone / glycolide copolymer (95 :5) pellets, 3 g of polyethylene glycol (8,000 MW) flake and 3 g of polyethyleneglycol (20,000MW) flake were added to a teflon mixing container. The teflon container was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. Next, the teflon container was mixed for 2.5 min at high intensity (3500 rpm). During mixing, the internal friction causes the caprolactone / glycolide copolymer (95 :5) and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the 0-TCP powder into the molten polymer blend. The molten ink was poured onto a glass plate and flatten with a spatula to approximately 3 mm thick layer for cooling. It was cooled for 10-15 min. The mixture was returned to the teflon container and mixed for 4 more minutes at a high intensity (3500 rpm). The mixing / coolingprocess was repeated for a total of one 2.5 minute mix and three 4 min mixes at 3500 rpm. Afterthe ink was cooled afterthe fourth and final mix, shears were used to cut it into approximately 3 -4 mm pellets.

[0352] Filament Fabrication: 16 cc of 3-4 mm pellets were loaded into the hopper of a filament extruder (Filabot EX2 Filament Extruder). A 3x length extended melt filter nozzle (with filter screens removed) with 1.75 mm diameter hole size was used. A cooling fan was placed near the extrusion nozzle to speed up solidification of the extruded filament. The 1.75 mm diameter filament was extruded at extrusion temperature to 62°C and speed at ’A on the analog dial (approximately 1 cm / second extrusion speed).

[0353] 3D Printing: The 1.75 mm filament was loaded in a Prusa i3 MK3 S 3D printer. This filament material was printed using a 400 micron brass nozzle, 150°C extruder temperature, and 10 mm / s print speed.

[0354] Post Processing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible 0- TCP / caprolactone / glycolide copolymer (95 :5) composite. Scaffolds were dried for atleasttwelve hours to ensure residual water has evaporated from the porous scaffold before binding with a therapeutic agent like tBMP2. Scaffolds were sterilized by soaking for 2 -4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 10 A- 10C.

[0355] Ink formulation and scaffold #11

[0356] Method: To make a 16 cc batch of ink, 18 g of 0-TCP powder, 6 g of caprolactone / glycolide copolymer (90: 10) chips, 3 g of polyethylene glycol (8,000 MW) flake and 3 g of polyethyleneglycol (20,000MW) flake were added to a teflon mixing container. The teflon container was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder bl end before high rpm mixing. Next, the teflon container was mixed for 2 min at high intensity (3500 rpm). During mixing, the internal friction causes the caprolactone / glycolide copolymer (90:10) and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the 0-TCP powder into the molten polymer blend. The molten ink was poured onto a glass plate and flatten with a spatula to approximately 3 mm thick layer for cooling. It was cooled for 10-15 min. The mixture was returned to the teflon container and mixed for 5 more minutes at a high intensity (3500 rpm). The mixing / coolingprocess was repeated for a total of one 2 minute mix and three 5 min mixes at 3500 rpm. After the ink was cooled after the fourth and final mix, shears were used to cut it into approximately 3 -4 mm pellets.

[0357] Filament Fabrication: 16 cc of 3-4 mm pellets were loaded into the hopper of a filament extruder (Filabot EX2 Filament Extruder). A 3x length extended melt filter nozzle (with filter screens removed) with 1.75 mm diameter hole size was used. A cooling fan was placed near the extrusion nozzle to speed up solidification of the extruded filament. The 1.75 mm diameter filament was extruded at extrusion temperature to 62°C and speed at ’A on the analog dial (approximately 1 cm / second extrusion speed).

[0358] 3D Printing: The 1.75 mm filament was loaded in a Prusa i3 MK3 S 3D printer. This filament material was printed using a 400 micron brass nozzle, 150°C extruder temperature, print bed temperature of 40°C, and 10 mm / s print speed.

[0359] Post Processing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible 0- TCP / caprolactone / glycolide copolymer (90: 10) composite. Scaffolds were dried for at least twelve hours to ensure residual water has evaporated from the porous scaffold beforebinding with a therapeutic agent like tBMP2. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 11 A-l 1C.

[0360] Ink formulation and scaffold #12

[0361] Method: To make a 8 cc batch of ink, 9 g of 0-TCP powder, 3 g of Poly(D,L-lactide-co- glycolide) copolymer (50:50) chunks, 1.5 g of polyethylene glycol (8,000 MW) flake, and 1.5 g of polyethylene glycol (20,000 MW) flake were added to a teflon mixing container. The teflon container was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. Next, the teflon container was mixed for 2 min at high intensity (3500 rpm). During mixing, the internal friction causes the Poly(D,L-lactide-co-glycolide) copolymer (50:50) and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitates intimate dispersion of the 0-TCP powder into the molten polymer blend. The molten ink was poured onto a glass plate and flatten with a spatula to approximately 3 mm thick layer for cooling. It was cooled for 10-15 min. The mixture was returned to the teflon container and mixed for 2.5 more minutes at a high intensity (3500 rpm). The mixing / coolingprocess was repeated for a total of one 2 minute mix and two 2.5 min mixes at 3500 rpm. After the ink was cooled after the third and final mix, shears were used to cut it into approximately 3 -4 mm pellets.

[0362] Filament Fabrication: 8 cc of 3-4 mm pellets were loaded into the hopper of a filament extruder (Filabot EX2 Filament Extruder). A 3x length extended melt filter nozzle (with filter screens removed) with 1.75 mm diameter hole size was used. A cooling fan was placed near the extrusion nozzle to speed up solidification of the extruded filament. The 1.75 mm diameter filament was extruded at extrusion temperature to 62°C and speed at ’A on the analog dial (approximately 1 cm / second extrusion speed).

[0363] 3D Printing: The 1.75 mm filament was loaded in a Prusa i3 MK3 S 3D printer. This filament material was printed using a 400 micron brass nozzle, 140°C extruder temperature, and 10 mm / s print speed.

[0364] Post Processing: 3D printed structures were soaked overnight in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible 0- TCP / Poly(D,L-lactide-co-glycolide) copolymer (50:50) composite. Scaffolds were dried for at least twelve hours to ensure residual water has evaporated from the porous scaffold beforebinding with a therapeutic agent like tBMP2. Scaffolds were sterilizedby soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in biosafety cabinet for approximately 12 hours. Images of the scaffold are shown in FIGS. 12A-12C.

[0365] Ink formulation and scaffold #13

[0366] Ink #13 is printed using a syringe-based melt extrusion printing method, for example, using methods as described for printing inks #1 -#4. Ink #13 is printed using fused filament fabrication 3D printing, for example, using methods as described for printing ink#5 and ink#6.

[0367] Ink formulation and scaffold #14

[0368] Ink #14 is printed using a syringe-based melt extrusion printing method, for example, using methods as described for printing inks #1 -#4. Ink #14 is printed using fused filament fabrication 3D printing, for example, using methods as described for printing ink#5 and ink#6.

[0369] Ink formulation and scaffold #15

[0370] Ink #9 is printed using a syringe-based melt extrusion printing method, for example, using methods as described for printing inks # 1 -#4. Ink # 15 is printed using fused filament fabrication 3D printing, for example, using methods as described for printing ink#5 and ink#6. Ink formulation and scaffold #16

[0371] Method: To make a 16cc batch of ink, 18 g of P-TCP powder, 6 g of polycaprolactone powder, 3 g of polyethylene glycol (8,000 MW) flake and 3 g of polyethylene glycol (35,000 MW) flake were added to a teflon mixing container. The teflon container was placed into a dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. The powder blend was then mixed for 2.5 min at high intensity (3500 rpm). During mixing, the internal friction causes the poly caprolactone and polyethylene glycol to melt, changing the ink to a viscou s molten liquid. This liquid phase mixing facilitates intimate dispersion of the P-TCP powder into the molten polymer blend. The molten ink was poured onto a glass plate and flattened with a spatula to approximately 3 mm thick layer for cooling. The ink was allowed to cool for 10-15 min. After this cooling step, the ink was mixed again for 2.5 min at 3500 rpm. This mixing and cooling process (10-15 min cooling followed by 2.5 min mixing at 3500 rpm) was repeated four times. After the ink was cooled following the fourth and final mix, shears were used to cut the ink into about 4mm to about 6mm feedstock squares for pellet formation.

[0372] Pellet Fabrication: A 850pm diameter nozzle was attached to the metal barrel of a heated, pneumatic extrusion device (e.g. an Allevi 3 bioprinter with a 5 mL stainless steel syringe barrel). 3-4 cc of 4-6 mm feedstock squares were loaded into the barrel. The barrel was heated to about 80 to about 120°C temperature, for example 100°C. After 15 min, additional feedstock squares were added to the barrel and pushed down with a spatula into the molten material until the barrel was full. After 10 additional minutes, the ink was checked to ensure full melting. The pneumatic pressure of the pneumatic extrusion device was then set to about 50 to about 100 psi, for example 55 psi. A platform was installed below the extrusion tip as a substrate on which to extrude pellets. In one example, the platform can be smooth silicone sheet material. A manually generated Marlin G-code was used to extrude up to 120 pellets in a rectangular array, resulting in pellets having about 3 mm to about 4 mm diameter and being roughly equiaxed.

[0373] 3DPrinting: The pellets were then loaded into the hopper of aPiocreatG5 FGF 3Dprinter. The material was printed using a nozzle of about 300 pm to about 1000 pm at about 105 to about 145°C nozzle temperature using an about 5mm / s to about 30mm / s printing speed.

[0374] Post Processing: The 3D printed structures were soaked for at least 16 hours in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible P-TCP / poly caprolactone composite. The scaffolds were dried for at least twelve hours to ensure residual water has evaporated from the porous scaffold before binding with tBMP2 protein. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in a biosafety cabinet for about 12 hours. Images of example scaffolds are shown in FIGS 13A- 13D and 14A-14D. An example scaffold is a gyroid scaffold, which has an interconnected, isotropic porous structure with no sharp comers or straight edges. These properties enable sufficient fluid transport within the scaffold structure and are amenable to cell attachment.

[0375] Ink formulation and scaffold #17-#24

[0376] Inks #17 and #20-24 are printed into scaffolds using the pellet-based method as described for ink formulation and scaffold #16.

[0377] Ink formulation and scaffold #18

[0378] Method: To make a 16cc batch of ink, 18 g of P-TCP powder, 6 g of Caprolactone / Glycolide copolymer (95:5) pellets, 3 g of polyethylene glycol (8,000 MW) flake and 3 g of polyethylene glycol (35,000 MW) flake was added to a teflon mixing container. The teflon container was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. The composition was mixed for 1 .5 min at high intensity (3500 rpm). During mixing the internal friction caused the caprolactone / glycolide copolymer and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitated intimate dispersion of the P-TCP powder into the molten polymer blend. The molten ink was poured onto a glass plate and flattened with a spatula to an approximately 3 mm thick layer for cooling. The ink was cooled for 10-15 min, and mixed for 1.5 more minutes at 3500 rpm. This mixing / cooling process was repeated for a total of four 1 .5 -minute mixes at 3500 rpm. After the ink was cooled following the fourth and final mix, shears were used to cut the ink into approximately 4-6 mm squares for pelletizing feedstock.

[0379] Pellet Fabrication: An 850 pm diameter nozzle was attached to the metal barrel of a heated, pneumatic extrusion device (e.g. an Allevi 3 bioprinter with a 5 mL stainless steel syringe barrel) and 3-4 cc of 4-6 mm ink feedstock squares were loaded into the barrel. The barrel was heated to 80-120°C temperature, for example 100°C, and left for 15 minutes. After 15 minutes more feedstock was added to the barrel and pushed down with a spatula into molten material until the barrel was full and left for 10 minutes. After 10 minutes the barrel was checked to ensure the ink was fully melted. The pneumatic pressure of the pneumatic extrusion device was then set to about 50-100 psi, for example 55 psi. A platform was installed below the extrusion tip as a substrate on which to extrude pellets. In one example, the platform can be smooth silicone sheet material. A manually generated Marlin G-code was used to extrude up to 120 pellets in a rectangular array, resulting in pellets having about 2 mm to about 3 mm diameter and being roughly equiaxed. 3DPrinting: The pellets were then loaded into the hopper of aPiocreat G5 FGF 3D printer. The material was printed using a nozzle of about 300 pm to about 1000 pm at about 105 to about 145°C nozzle temperature using an about 5mm / s to about 30mm / s printing speed.

[0380] Post Processing: The 3D printed structures were soaked for at least 16 hours in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible P-TCP and caprolactone / glycolide copolymer composite. The scaffolds were dried for at least twelve hours to ensure residual water has evaporated from the porous scaffold beforebinding with tBMP2 protein. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in a biosafety cabinet for about 12 hours. Images of example scaffolds are shown in FIGS 15 A-l 5B. After soaking and drying, the scaffold contained 75 Wt% P-TCP powder and 25 Wt% Caprolactone / Glycolide copolymer (95:5).

[0381] Ink formulation and scaffold #19

[0382] Method: To make a 16cc batch of ink, 18 g of P-TCP powder, 6 g of Caprolactone / Glycolide copolymer (90:10) chips, 3 g of polyethylene glycol (8,000 MW) flake and 3 g of polyethylene glycol (35,000 MW) flake was added to a teflon mixing container. The teflon container was placed in dual asymmetric centrifugal mixer (FlackTek Speedmixer) and mixed at low intensity (300 rpm) for 2 min to homogenize the powder blend before high rpm mixing. The composition was mixed for 1.5 min at high intensity (3500 rpm). During mixing the internal friction caused the caprolactone / glycolide copolymer and polyethylene glycol to melt, changing the ink to a viscous molten liquid. This liquid phase mixing facilitated intimate dispersion of the P-TCP powder into the molten polymer blend. The molten ink was poured onto a glass plate and flattened with a spatula to an approximately 3 mm thick layer for cooling. The ink was cooled for 10-15 min, and mixedfor 1.5 more minutes at 3500 rpm. This mixing / cooling process was repeated for a total of four 1.5 -minute mixes at 3500 rpm. After the ink was cooled following the fourth and final mix, shears were used to cut the ink into approximately 4 -6 mm squares for pelletizing feedstock.

[0383] Pellet Fabrication: An 850 pm diameternozzle was attachedto the metal barrel of a heated, pneumatic extrusion device (e.g. an Allevi 3 bioprinter with a 5 mL stainless steel syringe barrel) and 3-4 cc of 4-6 mm ink feedstock squares were loaded into the barrel. The barrel was heated to 80-120°C temperature, for example 100°C, and left for 15 minutes. After 15 minutes more feedstock was added to the barrel and pushed down with a spatula into molten material until the barrel was full and left for 10 minutes. After 10 minutes the barrel was checked to ensure the ink was fully melted. The pneumatic pressure of the pneumatic extrusion device was then set to about 50-100 psi, for example 55 psi. A platform was installed below the extrusion tip as a substrate on which to extrude pellets. In one example, the platform can be smooth silicone sheet material. A manually generated Marlin G-code was used to extrude up to 120 pellets in a rectangular array, resulting in pellets having about 2 mm to about 3 mm diameter and being roughly equiaxed.

[0384] 3DPrinting: The pellets were then loaded into the hopper of aPiocreatG5 FGF 3Dprinter. The material was printed using a nozzle of about 300 pm to about 1000 pm at about 105 to about 145°C nozzle temperature using an about 5mm / s to about 30mm / s printing speed.

[0385] Post Processing: The 3D printed structures were soaked for at least 16 hours in distilled water to dissolve the polyethylene glycol from the printed material, thus creating a porous and flexible P-TCP and caprolactone / glycolide copolymer composite. The scaffolds were dried for at least twelve hours to ensure residual water has evaporated from the porous scaffold beforebinding with tBMP2 protein. Scaffolds were sterilized by soaking for 2-4 hours in a 70% ethanol solution and allowed to dry in a biosafety cabinet for about 12 hours. Images of example scaffolds are shown in FIGS 16A-16B. After soaking and drying, the scaffold contained 75 Wt% P-TCP powder and 25 Wt% Caprolactone / Glycolide copolymer (90:10).

[0386] Structure properties

[0387] Physical properties of example scaffolds made using inks #1-#12 and 18-19 were determined and are outlined in Table 34.

[0388] Physical properties of example scaffolds madeusinginks# 16, 18, and 19 were determined and outline in Table 35.

[0389] Table 34. Properties of Examples Scaffolds Table 35. Properties of Example Scaffolds

[0390] The structures of this example are tested using Brunauer-Emmett-Teller (BET) surface area analysis by gas physisorption.

[0391] A compression test is also performed on the structures.

[0392] Example 3: Therapeutic Agent

[0393] A chimeric polypeptide comprising the BMP therapeutic peptide connected to five betatricalcium phosphate binding peptides was expressed and purified using standard expression and purification methods. The chimeric polypeptide is referred to as tBMP-2 and has the following sequence:

[0394] MPIGSLLADTTHHRPWTVIGESTHHRPWSIIGESSHHKPFTGLGDTTHHRPWGILAESTH HKPWTASGAGGSEGGGSEGGTSGATGAGTSTSGGGASTGGGTGQAKHKQRKRLKSSC KRHPLYVDFSDVGWNDWIVAPPGYHAFYCHGECPFPLADHLNSTNHAIVQTLVNSVNS KIPKACCVPTELSAISMLYLDENEKVVLKNYQDMVVEGCGCR (SEQ ID NO: 434).

[0395] Example 4: Device Manufacture

[0396] The 3D printed structure “Flexible 3 -layer membrane 3D printed with a 400 um nozzle” of Example 2 was combined with the tBMP-2 therapeutic agent of Example 3 to create a device. The scaffold was combined with tBMP-2 in a binding solution and unbound tBMP-2 was washed off the scaffold. The resulting device comprised the scaffold with bound tBMP-2. The device was lyophilized. Similar devices are prepared using 3D printed structures and growth factors herein. Example 5: Animal Models

[0397] One or more devices of Example 4 are tested in an animal model to demonstrate bone regeneration through pCT imaging and histological analysis. Indications can include lumbar spinal fusion (a 3D printed insert for spinal fusion cage), posterolateral (PLF) spine fusion (3D printed scaffold that spans transverse processes), tibial segmental defects (a 3D printed scaffold based on patient CT data), and / or alveolar ridge augmentation (a 3D printed thin barrier membrane).

[0398] The first study is a lapine posterolateral fusion model. The objective of this study is to evaluate the in vivo performance of test devices at varying concentrations of growth factor and masses of scaffold. The test groups are evaluated for spine fusion rate, new bone formation, and residual graft using radiographic plain films, microCT, biomechanical and histological endpoints at 8 weeks following implantation.

[0399] A dorsal midline skin incision, approximately 15 centimeters long, is made in each rabbit from LI to the sacrum, and then the fascia and muscle are incised over the L5-L6 transverse processes (TPs). The TPs are then decorticated with a high-speed burr. The test devices are placed over the transverse processes and fascia and skin are closed and stapled. To ensure the animals are comfortable, analgesics are administered according to IACUC approval. Animals are fed ad libitum and allowed to move about their cages without restriction. No postoperative immobilization devices are used. During the following weeks, the animals are observed closely and given additional pain medication based on their mobility, diet, disposition, andgeneral activity that would signify increased pain. The rabbits are radiographed postoperatively and at 8 weeks. MicroCT morphometry analysis is performed using a region of interest (RO I) placed across the fusion site and areas of bone are calculated. Fusion sites of each animal are processed for histology at 8 weeks.

[0400] The second study is a sheep interbody fusion model to evaluate test devices in the interbody space of sheep lumbar spine. Sheep undergo interbody fusion through a lateral approach. Implanted motion segments are stabilized with pedicle screw and rod fixation. PEEK interbody spacers are placed in the interbody space following discectomy and endplate prep. Spacers are filled with test device. Sheep are euthanized at 6 months post-op after review of inlife MDCTs at 4, 8, and 12 weeks post operation. After euthanasia, pCT, manual palpation of implanted motion segments, calcified (plastic embedded) standard histology (H&E and Trichrome), H4C (growth factor), and histomorphometry is performed. Example 6: Cytotoxicity Assay

[0401] An in vitro cytotoxicity assay was performed to determine cell response, specifically toxic effects, when exposed to extracts from the 3D printed scaffolds. The outcome of this in vitro study provides insight on the toxicity of the biomaterial components of the scaffolds (shown in Table 36) when implanted in the body . All cytotoxicity tests were performed using guidance from the International Organization for Standardization (ISO) 10993 -5:2009 standard.

[0402] Table 36. Scaffold Formulations for Cytotoxicity Assay

[0403] Briefly, L929 mouse fibroblast cells were seeded in 24 -well plates at seeding density of lxlO5cells / per well and placed in a humidified incubator at 37°C and 5% CO2 overnight. Sterile scaffold extracts (scaffolds shown in table 36) were prepared by first submerging scaffolds in media for 24 hours then adding these extracts to the 24 -well plates seeded with the L929 mouse fibroblast cell line. After 24 hours, visual examination of cells exposed to the extracts was used to determine if there was a cytotoxic cell response after cells were exposed to scaffolds. Cytotoxicity was considered present if cells were detached, lysed, or had changes in morphology. Microscopy images of cells exposed to the scaffolds of table 36 are shown in FIG. 17A. The cells were examined and cytotoxicity scores were calculated accordingto the following cytotoxicity scale defined in ISO 10993-5 :2009 standard: Scale 0 = Non cytotoxic, Scale 1 = slightly cytotoxic, Scale 2 = mildly cytotoxic, Scale 3 = moderately cytotoxic , Scale 4 = severely cytotoxic.

[0404] High Density Polyethylene (HDPE) (negative control) scored an average of less than 1 which is not cytotoxic to slightly cytotoxic. 0.1% Zincdiethyldithiocarbamate (ZDEC) (positive control) scored an average of 4 which is severely cytotoxic, and had widespread cell detachment. 95 :5 and 90: 10 scored 0 indicating that they are non cytotoxic. The OT sample scored less than 1, indicating that it is non cytotoxic to slightly cytotoxic. There was minimal to no cell detachment in all of the 3D printed scaffold samples and they all were similar in appearance to the cell-only control. Image scores are shown in FIG. 17B.

[0405] Example 7: Therapeutic Living Bioreactors for Bone Marrow Formation

[0406] A therapeutic living bioreactor was generated using a 3D printed three-dimensional ceramic scaffold loaded with the therapeutic agent tBMP-2. The three-dimensional scaffold can also be formed using electrospun biodegradable materials (e.g., ceramics), or combinations thereof. The scaffold was implanted into a segmental defect in the tibia of a goat. 8 weeks after the initial implantation of the therapeutic living bioreactor early bone marrow formation was observable, demonstrating the emergence of a fatty bone marrow niche and new bone formation (FIG. IB). The formation of osteoblasts, fibrocartilage, and fibrous tissue was also observable after 8 weeks (FIG. 1C). Stable bone marrow formation was observable after 26 weeks (FIG. ID).

[0407] This example is repeated with additional therapeutic living bioreactors, as exemplified in FIGS. 19A-19C, which all comprise a 3D printed scaffold comprising a ceramic material, such as beta-tricalcium phosphate. In one example, FIG. 19A, the bioreactor further comprises an autograft or allograft material. In another example, FIG. 19B, the bioreactor further comprises a composition comprising a structure of electrospun fibers of 70% by weight beta-tricalcium phosphate and 30% by weight PLGA, and a therapeutic agent tBMP-2, where the therapeutic agent is bound to the beta-tricalcium phosphate of the electrospun fibers. In another example, FIG. 19C, the bioreactor comprises a therapeutic agent tBMP-2, which is bound to the ceramic material of the 3D printed scaffold.

[0408] The living bioreactors are implanted into a subject, and the production of bone marrow is ob served . In some experiments, the therapeutic agents in these ex amples e.g. , autograft, allograft, and / or tBMP-2), are substituted with a different therapeutic agent. For instance, a different therapeutic protein that may induce cell differentiation of cells from the subject or cells that are added exogenously . In some experiments, the therapeutic agents in these examples, are combined with one or more additional therapeutic agents. For instance, the one or more additional therapeutic agents may induce cell differentiation of cells from the subject or cells that are added exogenously.

[0409] After implantation of the living bioreactors into the subject, in some examples, cells are delivered to the implantation site, where the living bioreactors may form a niche for the cells (e.g., see FIG. 1A). The experiments include confirming viability of cells added to the niche, and confirming stable phenotype and / or production of a therapeutic from the cell.

[0410] In another experiment, a growth factor of Table 1 was tethered to a ceramic scaffold via a peptide of Table 2, and the resulting implant was placed into hamstring muscles of a rat. Gross bone formation was assessed and histological observation was done, which showed the presence of bone, cartilage and marrow formation at 28 days. At the 28 day harvest, implants ranged from 1-2 cm diameter. The implants had a hard, outer shell with evidence of bone marrow and red blood cells within (FIG. 20). Bone marrow genesis was extensive, as shown in FIG. 21. The implants were also rich in red blood cells, as shown in FIG. 22.

[0411] Example 8: Induction of Cell Differentiation and Delivery of Therapeutics Using Therapeutic Living Bioreactors

[0412] A variety of therapeutic living bioreactors are contemplated, including bioreactors containing a variety of therapeutic agents useful for the induction of cell differentiation of autologous and allogeneic cells (allograft or autograft cells). If implanted in a subject, the anatomic location of the therapeutic living bioreactors may be percutaneously available, such as a sub costal location. Non-limiting example living bioreactors are described elsewhere herein, including Example 7.

[0413] In one example, a therapeutic living bioreactor is used for metabolic cell therapies. One example of a metabolic cell therapy for which a therapeutic living bioreactor is used is insulin or a GLP1 agonist release. This insulin or GLP1 agonist releasing therapeutic living bioreactor is useful in a subject with diabetes, obesity, fatty liver disease, or cardiometabolic disorders.

[0414] In a further example, a therapeutic living bioreactor is used for therapeutic delivery such as antibody or recombinant biologic delivery. This protein delivery can be used as an alternative to infusion. It is contemplated that a variety of therapeutics and / or pharmaceuticals can be similarly delivered via therapeutic living bioreactors. Advantages of this administration include precise localization, persistent delivery of therapeutics and / or pharmaceuticals, sustained viability of cells that produce the therapeutic, generation of a protective bony structure to protect cells contained within, and anatomically favorable placement anywhere in the body that permits percutaneous access.

[0415] In another example, a therapeutic living bioreactor is used to develop an induced niche to support the immune system. This induced niche is useful for the production of lymphocytes in a subject with e.g., an immune disorder.

[0416] In another example, the induced living bioreactor may be used in a sensing or diagnostic capacity to monitor or measure biomarkers. The measurement of those biomarkers may inform the delivery or actuation of the living bioreactor system to delivery therapeutics.

[0417] In another example, the induced living bioreactor system may be used ex vivo or as a stand alone system to enable production of cells in a manufacturing environment. Example 9: Manufacturing with Therapeutic Living Bioreactors

[0418] Therapeutic living bioreactors are also capable of imparting stimulatory signals on surfaces and within vessels. Useful applications of these properties include use of therapeutic living bioreactors within tissue manufacturing vessels such as lab grown cultures.

[0419] Example 10: Bioreactor Implant

[0420] A bioreactor was formed comprising a 3D printed structure and a growth factor. The 3D printed structure was fabricated using the Formulation #2 described above, having 43% bTCP ceramic, 33% polymer (95 :5 caprolactone / glycolide copolymer), and 24% polyethylene glycol pore former. After removal of the pore former, the 3D structure is 57% bTCP ceramic and 43% polymer (95:5 caprolactone / glycolide copolymer). The 3D structure is shown in different orientations in FIGS. 23A-23B.

[0421] In a first example, the 3D structure is not bound to a therapeutic agent, and instead serves as an osteoconductive space-maintaining structure. The hollow space inside the 3D structure may comprise a therapeutic agent. For example, a growth factor of Table 1 . The hollow space inside the 3D structure may comprise the therapeutic agent and a second ceramic structure, where the therapeutic agent may be bound to the second ceramic structure. For instance, bound via a peptide of Table 2.

[0422] In a second example, the 3D structure is bound by a therapeutic agent, such as a growth factor of Table 1 via a peptide of Table 2.

[0423] In a third example, a multilayer bioreactor is prepared comprising the 3D printed structure of FIGS. 23A-23B as a first ceramic structure (101), a second ceramic structure shell (102), and an internal ceramic structure (103), as shown in FIG. 24. The third ceramic scaffold may be 3D printed. The second ceramic structure may be in a granular form, a porous form, a powder, a putty, a paste, fiber form, or a coating on the surface of the first and / or third structures.

[0424] For any of these examples, the therapeutic peptide may comprise two therapeutic peptides. For instance, BMP2 as the first therapeutic peptide, and a second therapeutic peptide from Table 1 (e.g., epidermal growth factor (EGF), platelet derived growth factor (PDGF), insulin like growth factor (IGF- 1), fibroblast growth factor (F GF), fibroblast growth factor 2 (FGF2), fibroblast growth factor 18 (FGF18), transforming growth factor alpha (TGF-a), transforming growth factor beta (TGF-P), transforming growth factor beta 1 (TGF-pi), transforming growth factor beta 3 (TGF-P3), osteogenic protein 1 (OP-1), osteogenic protein 2 (OP-2), osteogenic protein 3 (OP-3), bone morphogenetic protein 3 (BMP-3), bone morphogenetic protein 4 (BMP-4), bone morphogenetic protein 5 (BMP-5), bone morphogenetic protein 6 (BMP-6), bone morphogenetic protein 7 (BMP-7), bone morphogenetic protein (BMP-9), bone morphogenetic protein 10 (BMP- 10), bone morphogenetic protein 11 (BMP-11), bone morphogenetic protein 12 (BMP- 12), bone morphogenetic protein 13 (BMP-13), bone morphogenetic protein 15 (BMP-15), delta-like ligand-4 (DLL4), dentin phosphoprotein (DPP), vegetal related growth factor (VGR), growth differentiation factor 1 (GDF-1), growth differentiation factor 3 (GDF-3), growth differentiation factor 5 (GDF-5), growth differentiation factor 6 (GDF-6), growth differentiation factor 7 (GDF- 7), growth differentiation factor 8 (GDF8), growth differentiation factor 11 (GDF11), growth differentiation factor 15 (GDF15), vascular endothelial growth factor (VEGF), hyaluronic acid binding protein (HABP), collagen binding protein (CBP), fibroblast growth factor 18 (FGF-18), keratinocyte growth factor (KGF), tumor necrosis factor alpha (TNFa), tumor necrosis factor (TNF)- related apoptosis inducing ligand (TRAIL), wnt family member 1 (WNT1), wnt family member2 (WNT2), wntfamily member 2B (WNT2B), wntfamily member 3 (WNT3), wntfamily member 3 A (WNT3 A), wnt family member 4 (WNT4), wnt family member 5 A (WNT5 A), wnt family member 5B (WNT5B), wnt family member 6 (WNT6), wnt family member 7 A (WNT7A), wnt family member 7B (WNT7B), wnt family member 8A (WNT8A), wnt family member 8B (WNT8B), wnt family member 9A (WNT9A), wnt family member 9B (WNT9B), wnt family member 10A (WNT10 A), wntfamily member 1 OB (WNT 1 OB), wntfamily member 11 (WNT11), or wnt family member 16 (WNT16), or a mature peptide or functional portion thereof.

[0425] In an example, the bioreactor implants of this example are utilized in a cell therapy method. The bioreactor can serve as a support for the cell therapy. For instance, the cell therapy is introduced into a subject with the bioreactor.

[0426] In an example, the bioreactor implants of this example produce bone marrow in a subject implanted with the bioreactor implant.

[0427] In an example, the bioreactor implants of this example produce lymphocytes in a subject implanted with the bioreactor implant.

[0428] In an example, the bioreactor implants of this example induce T cell formation in a subject implanted with the bioreactor implant.

[0429] In an example, the bioreactor implants of this example are utilized in a tissue replacement or tissue graft procedure.

Claims

CLAIMSWhat is claimed is:1 . A method of treating a subject, the method comprising delivering to the subject a device comprising a first three-dimensional structure and a first therapeutic agent tethered to the three- dimensional structure via a first targeting moiety; wherein the three-dimensional structure comprises calcium phosphate and optionally a polymer, the calcium phosphate is present in the three-dimensional structure at 50% to 100% by weight, and the polymer is present in the three-dimensional structure at 0% to 50% by weight; wherein the method of treating (i) comprises a cell therapy, a tissue replacement therapy, or a tissue graft and / or (ii) results in bone marrow formation in the subject, production of lymphocytes in the subject, or T cell formation in the subject, or a combination of two or more thereof; and wherein the first therapeutic agent comprises bone morphogenetic protein 2 (BMP-2), epidermal growth factor (EGF), platelet derived growth factor (PDGF), insulin like growth factor (IGF-1), fibroblast growth factor (FGF), fibroblast growth factor 2 (FGF2), fibroblast growth factor 18 (FGF18), transforming growth factor alpha (TGF-a), transforming growth factor beta (TGF-P), transforming growth factor beta 1 (TGF-pi), transforming growth factor beta 3 (TGF-P3), osteogenic protein 1 (OP-1), osteogenic protein 2 (OP-2), osteogenic protein 3 (OP-3), bone morphogenetic protein 3 (BMP-3), bone morphogenetic protein 4 (BMP -4), bone morphogenetic protein 5 (BMP-5), bone morphogenetic protein 6 (BMP-6), bone morphogenetic protein 7 (BMP-7), bone morphogenetic protein (BMP-9), bone morphogenetic protein 10 (BMP-10), bone morphogenetic protein 11 (BMP-11), bone morphogenetic protein 12 (BMP- 12), bone morphogenetic protein 13 (BMP-13), bone morphogenetic protein 15 (BMP-15), delta -like ligand-4 (DLL4), dentin phosphoprotein (DPP), vegetal related growth factor (V GR), growth differentiation factor 1 (GDF-1), growth differentiation factor 3 (GDF-3), growth differentiation factor 5 (GDF-5), growth differentiation factor 6 (GDF-6), growth differentiation factor 7 (GDF-7), growth differentiation factor 8 (GDF8), growth differentiation factor 11 (GDF11), growth differentiation factor 15 (GDF15), vascular endothelial growth factor (VEGF), hyaluronic acid binding protein (HABP), collagen binding protein (CBP), fibroblast growth factor 18 (FGF-18), keratinocyte growth factor (KGF), tumor necrosis factor alpha (TNFa), tumor necrosis factor (TNF)- related apoptosis inducing ligand (TRAIL), wnt family member 1 (WNT1), wnt family member 2 (WNT2), wnt family member 2B (WNT2B), wnt familymember 3 (WNT3), wnt family member 3 A (WNT3 A), wnt family member 4 (WNT4), wnt family member 5A (WNT5 A), wnt family member 5B (WNT5B), wnt family member 6 (WNT6), wnt family member 7A (WNT7A), wnt family member 7B (WNT7B), wnt family member 8 A (WNT8A), wnt family member 8B (WNT8B), wnt family member 9A (WNT9A), wnt family member 9B (WNT9B), wnt family member 10A (WNT10A), wnt family member 1OB (WNT 1 OB), wnt family member 11 (WNT11), or wnt family member 16 (WNT 16), or a mature peptide or functional portion thereof.

2. The method of claim 1, wherein the device comprises a second therapeutic agent, wherein the second therapeutic agent is BMP -2, and the first therapeutic agent is the epidermal growth factor (EGF), platelet derived growth factor (PDGF), insulin like growth factor (IGF-1), fibroblast growth factor (FGF), fibroblast growth factor 2 (FGF2), fibroblast growth factor 18 (FGF18), transforming growth factor alpha (TGF-a), transforming growth factor beta (TGF-P), transforming growth factor beta 1 (TGF-pi), transforming growth factor beta 3 (TGF-P3), osteogenic protein 1 (OP-1), osteogenic protein 2 (OP-2), osteogenic protein 3 (OP-3), bone morphogenetic protein 3 (BMP-3), bone morphogenetic protein 4 (BMP-4), bone morphogenetic protein 5 (BMP-5), bone morphogenetic protein 6 (BMP-6), bone morphogenetic protein 7 (BMP-7), bone morphogenetic protein (BMP-9), bone morphogenetic protein 10 (BMP-10), bone morphogenetic protein 11 (BMP-11), bone morphogenetic protein 12 (BMP-12), bone morphogenetic protein 13 (BMP-13), bone morphogenetic protein 15 (BMP-15), delta-like ligand-4 (DLL4), dentin phosphoprotein (DPP), vegetal related growth factor (VGR), growth differentiation factor 1 (GDF-1), growth differentiation factor 3 (GDF-3), growth differentiation factor 5 (GDF-5), growth differentiation factor 6 (GDF-6), growth differentiation factor 7 (GDF- 7), growth differentiation factor 8 (GDF8), growth differentiation factor 11 (GDF11), growth differentiation factor 15 (GDF15), vascular endothelial growth factor (VEGF), hyaluronic acid binding protein (HABP), collagen binding protein (CBP), fibroblast growth factor 18 (FGF-18), keratinocyte growth factor (KGF), tumor necrosis factor alpha (TNFa), tumor necrosis factor (TNF)- related apoptosis inducing ligand (TRAIL), wnt family member 1 (WNT1), wnt family member 2 (WNT2), wnt family member 2B (WNT2B), wnt family member 3 (WNT3), wnt family member 3A (WNT3 A), wnt family member 4 (WNT4), wnt family member 5A (WNT5A), wnt family member 5B (WNT5B), wnt family member 6 (WNT6), wnt family member 7A (WNT7A), wnt family member 7B (WNT7B), wnt family member 8 A (WNT8A), wnt family member 8B (WNT8B), wnt family member 9 A (WNT9A), wnt family member 9B (WNT9B), wnt family member 10A (WNT10A), wnt family member 10B (WNT10B), wntfamily member 11 (WNT11), or wnt family member 16 (WNT16), or mature peptide or functional portion thereof.

3. The method of claim 2, wherein the second therapeutic agent is tethered to the three- dimensional structure via a second targeting moiety.

4. The method of any one or claims 1 -3, wherein the calcium phosphate is present in the three-dimensional structure at 50% to 70% by weight, and the polymer is present in the three- dimensional structure at 30% to 50% by weight.

5. The method of any one or claims 1 -4, wherein the polymer comprises poly caprolactone, caprolactone / glycolide copolymer, poly(D,L-lactide-co-glycolide) copolymer, poly(lactic-co- gly colic acid) (PLGA), or dioxanone / L-lactide copolymer, or a combination thereof.

6. The method of claim 5, wherein the polymer comprises caprolactone / glycolide copolymer.

7. The method any one of the preceding claims, wherein the three-dimensional structure has a density of 1 g / cm3to 3 g / cm3.

8. The method of any one of the preceding claims, wherein the three-dimensional structure has an open porosity of 15% to 45%.

9. The method of any one of the preceding claims, wherein the three-dimensional structure comprises a fiber having a diameter of 325 pm and 475 pm.

10. The method of any one of the preceding claims, wherein the three-dimensional structure has a plurality of micropores.

11. The method of claim 10, wherein the micropores have an average pore size of about 1 micron to about 500 microns, or about 50 microns to about 250 microns, or about 150 microns in diameter.

12. The method of any one of the preceding claims, wherein the three-dimensional structure has a strut diameter of about 300 micrometers to about 600 micrometers.

13. The method of any one of the preceding claims, comprising delivering to the subject the cell therapy.

14. The method of any one of the preceding claims, comprising delivering the subject a tissue graft.

15. The method of any one of the preceding claims, comprising delivering to the subject insulin, a GLP1 agonist, antibody, and / or recombinant biologic.

16. The method of any one of the preceding claims, comprising delivering to the subject a second three-dimensional structure.

17. The method of claim 16, wherein the second three-dimension structure comprises calcium phosphate and a polymer.

18. The method of claim 17, wherein calcium phosphate is present in the second three- dimensional structure at 50% to 70% by weight of the second three-dimensional structure, and the polymer is present in the second three-dimensional structure at 30% to 50% by weight of the second three-dimensional structure.

19. The method of claim 17 or claim 18, wherein the polymer comprises poly caprolactone, caprolactone / glycolide copolymer, poly(D,L-lactide-co-glycolide) copolymer, poly(lactic-co- gly colic acid) (PLGA), or dioxanone / L-lactide copolymer, or a combination thereof.

20. The method of any one of claims 16-19, wherein the second three-dimensional structure is a granular form, a porous form, a powder, a putty, a paste, or fiber form.

21. The method of any one of claims 16-20, wherein the second three-dimensional structure may be printed using additive manufacturing.

22. The method of any one of the preceding claims, wherein the first three-dimensional structure is a granular form, a porous form, a powder, a putty, a paste, or fiber form.

23. The method of any one of the preceding claims, wherein the first three-dimensional structure may be printed using additive manufacturing.

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