Compositions, methods, and kits relating to an immune isolating device with improved diffusion

Abstract

The present disclosure provides compositions, methods, and kits related to immunoisolation of cells and tissues. In particular, the present disclosure provides improved compositions, methods, and kits for encapsulating cells and / or tissues within an immune isolating device with improved diffusion to protect the cells / or tissues from host immune rejection.

Description

[0001]Atty. Docket No. UM-42565.601COMPOSITIONS, METHODS, AND KITS RELATING TO AN IMMUNE ISOLATING DEVICE WITH IMPROVED DIFFUSION CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 546,676, filed October 31, 2023, and U.S. Provisional Patent Application No. 63 / 669,732, filed July 11, 2024, each of which is incorporated by reference herein in its entirety. SEQUENCE LISTING The text of the computer readable sequence listing filed herewith, titled “UM-42565- 601_SQL”, created October 30, 2024, having a file size of 4,623 bytes, is hereby incorporated by reference in its entirety. GOVERNMENTSUPPORTThis invention was made with government support under HD104173 awarded by the National Institutes of Health. The government has certain rights in the invention. FIELDThe present disclosure provides compositions, methods, and kits related to immunoisolation of cells and tissues. In particular, the present disclosure provides improved compositions, methods, and kits for encapsulating cells and / or tissues within an immune isolating device with improved diffusion to protect the cells / or tissues from host immune rejection. BACKGROUNDFor young women of reproductive age who are diagnosed with cancer, receiving chemotherapy treatments depletes the ovarian follicle reserve and consequently alters pubertal development. Ovarian tissue grafting is one of the few options for preserving fertility in these patients. However, maintaining the health of the graft to ensure its proper functioning is difficult. One previous technology is provided by U.S. Pat. No. 11,786,560, which is incorporated herein by reference. However, additional technologies are needed to enhance the overall health of the transplanted tissue.Atty. Docket No. UM-42565.601SUMMARY The present disclosure provides compositions, methods, and kits related to immunoisolation of cells and tissues. In particular, the present disclosure provides improved compositions, methods, and kits for encapsulating cells and / or tissues within an immune isolating device having improved diffusion to protect the cells / or tissues from host immune rejection. Embodiments of the present disclosure include an immunoisolation device comprising: (a) a degradable inner core comprising a biological material; and (b) a non- degradable outer shell encapsulating the degradable inner core and comprising a thermosensitive microgel. In some embodiments, the non-degradable outer shell comprises from about 5% v / v microgels dispersed throughout the outer shell. In some embodiments, the non-degradable outer shell comprises from about 1% v / v to about 10% v / v (e.g., about 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2.0%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3.0%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, 4.0%, 4.1%, 4.2%, 4.3%, 4.4%, 4.5%, 4.6%, 4.7%, 4.8%, 4.9%, 5.0%, 5.1%, 5.2%, 5.3%, 5.4%, 5.5%, 5.6%, 5.7%, 5.8%, 5.9%, 6.0%, 6.1%, 6.2%, 6.3%, 6.4%, 6.5%, 6.6%, 6.7%, 6.8%, 6.9%, 7.0%, 7.1%, 7.2%, 7.3%, 7.4%, 7.5%, 7.6%, 7.7%, 7.8%, 7.9%, 8.0%, 8.1%, 8.2%, 8.3%, 8.4%, 8.5%, 8.6%, 8.7%, 8.8%, 8.9%, 9.0%, 9.1%, 9.2%, 9.3%, 9.4%, 9.5%, 9.6%, 9.7%, 9.8%, 9.9%, or 10.0% v / v) microgels dispersed throughout the outer shell. In some embodiments, the thermosensitive microgel comprises gelatin to provide a thermosensitive gelatin microgel. In some embodiments, the concentration of gelatin in the thermosensitive gelatin microgel is about 2.5% w / v. In some embodiments, the concentration of gelatin in the thermosensitive gelatin microgel is about 1% w / v to about 5% w / v (e.g., 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2.0%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3.0%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, 4.0%, 4.1%, 4.2%, 4.3%, 4.4%, 4.5%, 4.6%, 4.7%, 4.8%, 4.9%, or 5.0% w / v).Atty. Docket No. UM-42565.601In some embodiments, the degradable inner core and / or the non-degradable outer shell comprises a polyethylene glycol hydrogel (PEG). In some embodiments, (a) the degradable inner core can expand and is thus configured to allow a cell to grow; and (b) the non-degradable outer shell is semi-permeable and / or porous and is thus configured to allow exchange of metabolites with the environment outside the immunoisolation device and to protect the cell from immune reaction by immune system components present outside the immunoisolation device; and (c) the thermosensitive gelatin microgel melts when the immunoisolation device is implanted into the body (e.g., a human body having a substantially normal human body temperature (e.g., approximately 37°C (e.g., 35.5°C, 35.6°C, 35.7°C, 35.8°C, 35.9°C, 36.0°C, 36.1°C, 36.2°C, 36.3°C, 36.4°C, 36.5°C, 36.6°C, 36.7°C, 36.8°C, 36.9°C, 37.0°C, 37.1°C, 37.2°C, 37.3°C, 37.4°C, 37.5°C, 37.6°C, 37.7°C, 37.8°C, 37.9°C, 38.0°C, 38.1°C, 38.2°C, 38.3°C, 38.4°C, or 38.5°C). In some embodiments, the biological material comprises at least one of ovarian follicles, germ cells, and / or somatic cells. In some embodiments, the biological material is a differentiated stem cell or is genetically engineered. In some embodiments, the degradable inner core comprises a polyethylene glycol (PEG). In some embodiments, the thermosensitive gelatin microgel melts when implanted into the body to provide an immunoisolation device comprising pores in the non-degradable outer shell. In some embodiments, the non-degradable outer shell comprises about 50 to 250 pores (e.g., 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195, 200, 205, 210, 215, 220, 225, 230, 235, 240, 245, or 250 pores) per square nanometer. In some embodiments, the pores are about 25 µm to 35 µm (e.g., 25.0, 25.1, 25.2, 25.3, 25.4, 25.5, 25.6, 25.7, 25.8, 25.9, 26.0, 26.1, 26.2, 26.3, 26.4, 26.5, 26.6, 26.7, 26.8, 26.9, 27.0, 27.1, 27.2, 27.3, 27.4, 27.5, 27.6, 27.7, 27.8, 27.9, 28.0, 28.1, 28.2, 28.3, 28.4, 28.5, 28.6, 28.7, 28.8, 28.9, 29.0, 29.1, 29.2, 29.3, 29.4, 29.5, 29.6, 29.7, 29.8, 29.9, 30.0, 30.1, 30.2, 30.3, 30.4, 30.5, 30.6, 30.7, 30.8, 30.9, 31.0, 31.1, 31.2, 31.3, 31.4, 31.5, 31.6, 31.7, 31.8, 31.9, 32.0,Atty. Docket No. UM-42565.60132.1, 32.2, 32.3, 32.4, 32.5, 32.6, 32.7, 32.8, 32.9, 33.0, 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7, 33.8, 33.9, 34.0, 34.1, 34.2, 34.3, 34.4, 34.5, 34.6, 34.7, 34.8, 34.9, or 35.0 µm) in diameter. In some embodiments, the degradable inner core comprises a polyethylene glycol crosslinked with a degradable peptide (e.g., a degradable peptide comprising a matrix- metalloproteinase (MMP) sensitive sequence and / or a plasmin sensitive sequence). Embodiments of the present disclosure also include a method of preparing an immunoisolation device. For example, in some embodiments, the method comprises: (a) providing a biological material; (b) providing a degradable inner core comprising the biological material; (c) incorporating a thermosensitive gelatin microgel into a non-degradable outer shell; and (d) encapsulating the degradable inner core within the non-degradable outer shell. In some embodiments, providing a degradable inner core comprising the biological material comprises implanting the biological material within the degradable inner core. In some embodiments, providing the degradable inner core comprises: (a) mixing a hydrogel solution with a protease degradable linker peptide to provide a degradable hydrogel precursor solution; (b) cross-linking the degradable hydrogel precursor solution to provide an inner core comprising a degradable hydrogel; and (c) implanting the biological material in the inner core. In some embodiments, the degradable inner core and / or the non-degradable outer shell comprises a polyethylene glycol hydrogel. In some embodiments, incorporating the thermosensitive gelatin microgel into the non-degradable outer shell comprises mixing a PEG hydrogel and a microgel emulsion. In some embodiments, incorporating the thermosensitive gelatin microgel into the non- degradable outer shell comprises performing one or more of the following steps: (a) dissolving a thermosensitive gelatin in a first buffer to provide a thermosensitive gelatin solution; (b) running the thermosensitive gelatin solution through a droplet forming device comprising an aqueous inlet and an oil inlet that meet at a junction; (c) modulating the flow rate until a stable flow of droplets is produced and the droplets are pinched off at the junction to provide an emulsion; (d) transitioning the emulsion to an aqueous stage and storing in a second buffer; (e) adding a volume of the emulsion to a tube and centrifuging to provide a pellet comprising uniform gelatin microgels; (f) aspirating a supernatant to provide the uniform gelatinAtty. Docket No. UM-42565.601microgels; and / or (g) adding a polyethylene glycol hydrogel to the uniform gelatin microgels and mixing thoroughly to provide a polyethylene glycol hydrogel solution. In some embodiments, running the thermosensitive gelatin solution through a droplet forming device comprises running the thermosensitive gelatin solution through the aqueous inlet of the droplet forming device and running a fluorosurfactant solution in oil through the oil inlet of the droplet forming device. In some embodiments, the polyethylene glycol hydrogel solution comprises a gelatin microgel concentration of about 1.0% v / v in PEG, 1.0% v / v in PEG, 1.5% v / v in PEG, 2.0% v / v in PEG, 2.5% v / v in PEG, 3.0% v / v in PEG, 3.5% v / v in PEG, 4.0% v / v in PEG, 4.5% v / v in PEG, 5.0% v / v in PEG, 5.5% v / v in PEG, 6.0% v / v in PEG, 6.5% v / v in PEG, 7.0% v / v in PEG, 7.5% v / v in PEG, 8.0% v / v in PEG, 8.5% v / v in PEG, 9.0% v / v in PEG, 9.5% v / v in PEG, or 10.0% v / v in PEG. In some embodiments, the fluorosurfactant solution has a concentration of about 1% w / v (e.g., 0.8% w / v, 0.9% w / v, 1.0% w / v, 1.1% w / v, or 1.2% w / v). In some embodiments, the stable flow of droplets produces droplets about 25 µm to 35 µm in diameter (e.g., 25.0, 25.1, 25.2, 25.3, 25.4, 25.5, 25.6, 25.7, 25.8, 25.9, 26.0, 26.1, 26.2, 26.3, 26.4, 26.5, 26.6, 26.7, 26.8, 26.9, 27.0, 27.1, 27.2, 27.3, 27.4, 27.5, 27.6, 27.7, 27.8, 27.9, 28.0, 28.1, 28.2, 28.3, 28.4, 28.5, 28.6, 28.7, 28.8, 28.9, 29.0, 29.1, 29.2, 29.3, 29.4, 29.5, 29.6, 29.7, 29.8, 29.9, 30.0, 30.1, 30.2, 30.3, 30.4, 30.5, 30.6, 30.7, 30.8, 30.9, 31.0, 31.1, 31.2, 31.3, 31.4, 31.5, 31.6, 31.7, 31.8, 31.9, 32.0, 32.1, 32.2, 32.3, 32.4, 32.5, 32.6, 32.7, 32.8, 32.9, 33.0, 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7, 33.8, 33.9, 34.0, 34.1, 34.2, 34.3, 34.4, 34.5, 34.6, 34.7, 34.8, 34.9, or 35.0 µm in diameter). In some embodiments, encapsulating the degradable inner core within the non- degradable outer shell comprises (a) placing the inner core in a bead of a polyethylene glycol hydrogel solution and (b) cross-linking the polyethylene glycol hydrogel solution to form the non-degradable outer shell. In some embodiments, the inner core is configured to expand and contract. In some embodiments, the inner core is configured to allow the biological material to grow.Atty. Docket No. UM-42565.601In some embodiments, the method further comprises suspending the biological material in a culture or maintenance medium prior to encapsulation or preserving the biological material in an environment prior to encapsulation. Embodiments of the present disclosure also include a method of treating a subject who is in need of a bioactive substance, the method comprising: (a) providing an immunoisolation device comprising: (i) an inner core comprising a biological material; and (ii) a non-degradable outer shell encapsulating the inner core and comprising a thermosensitive gelatin microgel; and (b) implanting the immunoisolation device into the subject, wherein the thermosensitive gelatin microgel melts when implanted into the body. In some embodiments, the thermosensitive gelatin microgel melts when implanted into the body to provide an immunoisolation device comprising pores in the non-degradable outer shell. In some embodiments, the non-degradable outer shell comprises about 50 to 250 pores (e.g., 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195, 200, 205, 210, 215, 220, 225, 230, 235, 240, 245, or 250 pores) per square nanometer. In some embodiments, the pores are about 25 µm to 35 µm (e.g., 25.0, 25.1, 25.2, 25.3, 25.4, 25.5, 25.6, 25.7, 25.8, 25.9, 26.0, 26.1, 26.2, 26.3, 26.4, 26.5, 26.6, 26.7, 26.8, 26.9, 27.0, 27.1, 27.2, 27.3, 27.4, 27.5, 27.6, 27.7, 27.8, 27.9, 28.0, 28.1, 28.2, 28.3, 28.4, 28.5, 28.6, 28.7, 28.8, 28.9, 29.0, 29.1, 29.2, 29.3, 29.4, 29.5, 29.6, 29.7, 29.8, 29.9, 30.0, 30.1, 30.2, 30.3, 30.4, 30.5, 30.6, 30.7, 30.8, 30.9, 31.0, 31.1, 31.2, 31.3, 31.4, 31.5, 31.6, 31.7, 31.8, 31.9, 32.0, 32.1, 32.2, 32.3, 32.4, 32.5, 32.6, 32.7, 32.8, 32.9, 33.0, 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7, 33.8, 33.9, 34.0, 34.1, 34.2, 34.3, 34.4, 34.5, 34.6, 34.7, 34.8, 34.9, or 35.0 µm) in diameter. In some embodiments, the subject suffers from an endocrine deficiency. In some embodiments, the biological material produces a bioactive substance for which the subject is deficient. In some embodiments, the subject is a female who had cancer as a child, a female who has had a cytotoxic treatment, and / or a female who is in need of hormone therapy for menopause.Atty. Docket No. UM-42565.601Embodiments of the present disclosure also include a kit comprising: (a) degradable hydrogel precursor solution; (b) a non-degradable hydrogel precursor solution; and (c) a thermosensitive gelatin microgel. BRIEF DESCRIPTION OF THE DRAWINGS FIG.1A is a schematic of microgel production and incorporation into PEGG+ gels. FIG. 1B shows gelatin microgels in oil phase. FIG. 1C shows gelatin microgels in aqueous phase. Scale bars: 100 µm. FIG.2A shows the distribution of microgel diameters used in characterization. FIG. 2B shows pore diameter. FIG. 3 shows confocal images of PEGG+ hydrogels before melting and after 24 hours of melting. Scale bars: 100 µm. FIG. 4A shows diffusion of 40 kDa through PEGG+ hydrogel after incubation at 37°C. FIG.4B shows diffusion of 150 kDa through PEGG+ hydrogel after incubation at 37°C. FIG.5A shows oscillatory yield point for PEGG+ hydrogel. FIG.5B shows storage modulus PEGG+ hydrogel. FIG.5C shows loss modulus for PEGG+ hydrogel. FIG.5D shows oscillatory yield point for warm gelatin-melted PEGG+ hydrogel. FIG. 5E shows storage modulus for warm gelatin-melted PEGG+ hydrogel. FIG. 5F shows loss modulus for warm gelatin-melted PEGG+ hydrogel. FIG.6A shows mean grey value for the gelatin microgels in the 1% PEGG+ hydrogel concentration over 0 hour, 5 hours, and 24 hours after being placed in 37 °C environment. FIG. 6B shows mean grey value for the gelatin microgels in the 5% PEGG+ hydrogel concentration over 0 hour, 5 hours, and 24 hours after being placed in 37 °C environment. FIG. 6C shows mean grey value for the gelatin microgels in the 10% PEGG+ hydrogel concentration over 1 hour, 5 hours, and 24 hours after being placed in 37 °C environment. FIG. 7A shows gelatin microgels in DPBS. FIG. 7B shows gelatin microgels after being slow frozen with DMSO. FIG. 7C shows gelatin microgels after being slow frozen without DMSO. FIG.7D shows the change in microgel diameter due to slow freezing. FIG.8A shows diffusion of 4 kDa Dextran molecules through 0%, 1%, 5% and 10% PEGG+ hydrogel concentrations. FIG. 8B shows diffusion of 40kDa Dextran moleculesAtty. Docket No. UM-42565.601through 0% ,1%, 5% and 10% PEGG+ hydrogel concentrations. FIG. 8C shows diffusion of 150 kDa Dextran molecules through 0% ,1%, 5% and 10% PEGG+ hydrogel concentrations. FIG.8D shows diffusion of 66 kDa Dextran molecules through 0% ,1%, 5% and 10% PEGG+ hydrogel concentrations. Lowercase letters indicate groups that are statistically significant from each other where lowercase “b” corresponds to p<0.001 and where lowercase “c” corresponds to p<0.01. FIG.9A is a schematic of the cold and warm PEGG+ hydrogels. FIG.9B shows strain sweep storage modulus data of cold PEGG+ hydrogels. FIG. 9C shows strain sweep storage modulus data of warm PEGG+ hydrogels. FIG.9D shows complied yield point data from cold PEGG+ hydrogels. FIG.9E shows storage modulus for cold PEGG+ hydrogels. FIG.9F shows loss modulus for cold PEGG+ hydrogels. FIG. 9G shows complied yield point data from cold PEGG+ hydrogels. FIG.9H shows storage modulus for cold PEGG+ hydrogels. FIG.9I shows loss modulus for cold PEGG+ hydrogels. FIG. 10A shows a PEGG+ hydrogel immunoisolation device prior to implantation. FIG. 10B shows the PEGG+ hydrogel immunoisolation device visible after subcutaneous implantation. FIG. 10C shows the PEGG+ hydrogel immunoisolation device integrated with the skin of mouse after 20 weeks. FIG. 10D shows the PEGG+ hydrogel immunoisolation device after removal from an animal. FIG. 10E and FIG 10F show PEGG+ hydrogel immunoisolation devices contained in a fibrous capsule after removal. DETAILED DESCRIPTION The present disclosure provides compositions, methods, and kits related to immunoisolation of cells and tissues. In particular, the present disclosure provides improved compositions, methods, and kits for encapsulating cells and / or tissues within an immune isolating device with improved diffusion to protect the cells / or tissues from host immune rejection. Ovarian tissue grafting is one of the few options for preserving fertility and restoring ovarian endocrine function in pre-pubescent females who require chemotherapy. Therefore, it is important to maintain the health of the graft to ensure its proper functioning. An immune isolating device with improved diffusion enhances the health of the graft by protecting theAtty. Docket No. UM-42565.601ovarian tissue allograft while allowing the tissue to expand. The nanoporous nature of the hydrogel-based capsule allows the bidirectional exchange of soluble factors while maintaining the tissue graft isolated from the immune system. Furthermore, the thermosensitive gelatin microgels of the device enhance the immunoisolation device by increasing the nutrient flow and providing mechanical resilience to the graft. This technology can improve the health of the graft, and, thus, provide a solution for females undergoing ovarian tissue transplant. This technology also finds use for other types of transplants (e.g., types of cells and tissues that are not ovarian cells or tissues) for improving health of the graft. Section headings as used in this section and the entire disclosure herein are merely for organizational purposes and are not intended to be limiting. 1. Definitions Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the present document, including definitions, will control. Preferred methods and materials are described below, although methods and materials similar or equivalent to those described herein can be used in practice or testing of the present disclosure. All publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety. The materials, methods, and examples disclosed herein are illustrative only and not intended to be limiting. The terms “comprise(s),” “include(s),” “having,” “has,” “can,” “contain(s),” and variants thereof, as used herein, are intended to be open-ended transitional phrases, terms, or words that do not preclude the possibility of additional acts or structures. The singular forms “a,” “and” and “the” include plural references unless the context clearly dictates otherwise. The present disclosure also contemplates other embodiments “comprising,” “consisting of” and “consisting essentially of,” the embodiments or elements presented herein, whether explicitly set forth or not. For the recitation of numeric ranges herein, each intervening number there between with the same degree of precision is explicitly contemplated. For example, for the range of 6-Atty. Docket No. UM-42565.6019, the numbers 7 and 8 are contemplated in addition to 6 and 9, and for the range 6.0-7.0, the number 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, and 7.0 are explicitly contemplated. The phrase “in one embodiment” as used herein does not necessarily refer to the same embodiment, though it may. Furthermore, the phrase “in another embodiment” as used herein does not necessarily refer to a different embodiment, although it may. Thus, as described below, various embodiments of the invention may be readily combined, without departing from the scope or spirit of the invention. In addition, as used herein, the term “or” is an inclusive “or” operator and is equivalent to the term “and / or” unless the context clearly dictates otherwise. The term “based on” is not exclusive and allows for being based on additional factors not described unless the context clearly dictates otherwise. In addition, throughout the specification, the meaning of “a”, “an”, and “the” include plural references. The meaning of “in” includes “in” and “on.” As used herein, the term “polymer” refers to a material or a class of natural or synthetic substances composed of large molecules (e.g., macromolecules), which are multiples of simpler chemical units (e.g., monomers). As used herein, a polymer may be a heteropolymer (multiples of different types of monomer units), a homopolymer (multiples of a single type of monomer unit), or copolymer (formed by linking two or more different types of monomer units), and a polymer may be linear or branched. Representative polymers include polyamides (e.g., such as polypeptides), poly-N-substituted glycines (polypeptoids), polysaccharides, polyethylene glycol (PEG), plastics, polynucleotides (e.g., nucleic acids), and the like, where the polymers may be naturally occurring, non-naturally occurring, or synthetic. As used herein, the term “poly(ethylene glycol)”, abbreviated “PEG”, refers to a synthetic polymer of ethylene glycol. PEG is water-soluble and can be modified with various functional groups that allow one to tailor its chemistry, physical, and biological properties. As used herein, the abbreviation “PEGG+”, refers to a mixture of PEG and gelatin microgels. As used herein, the term “thermosensitive” refers to a material that is in one or more ways sensitive to heat or a change in temperature. An exemplary thermosensitive material is a microgel that is solid or has a high viscosity (i.e., such that it does not flow) at aAtty. Docket No. UM-42565.601temperature below approximately human body temperature (e.g., below approximately 35 to 37°C) and that undergoes a phase change such that it is a liquid or has a lower viscosity (i.e., such that it does flow) at a temperature that is at or above human body temperature (e.g., above 35°C). As used herein, the term “emulsion” refers to a fine dispersion of minute droplets of one liquid in another liquid in which it is not soluble or miscible. As used herein, the term “microgels” refers to a composition comprising microscopic solid particles that are suspended in a fluid and form a network structure that comprises chemically cross-linked three-dimensional polymer networks. Microgels are able to swell or shrink in response to a variety of external stimuli such as temperature, pH, ionic strength, electric field, and enzyme activities. See, e.g., Plamper and Richtering (2017) “Functional Microgels and Microgel Systems” Accounts of Chemical Research 50: 131–40; and Agrawal and Agrawal (2018) “Stimuli-Responsive Microgels and Microgel-Based Systems: Advances in the Exploitation of Microgel Colloidal Properties and Their Interfacial Activity” Polymers (Basel) 10: 418, each of which is incorporated herein by reference. As used herein, the term “gelatin” refers to a biopolymer prepared by thermal denaturing collagen (e.g., a heterogeneous mixture of proteins and peptides derived from collagen, trace impurities extracted from raw materials, and chemicals added intentionally or unintentionally during the manufacturing process). Gelatin obtained from collagen can be acidic or basic depending on the method of extraction. Gelatin can be extracted from the skin, bones, cartilage, and other connective tissue rich in collagen from animals (e.g., pigs, cows, fish, chicken, etc.). Gelatin undergoes thermoreversible crosslinking at cool temperatures (e.g., below 35oC) and solubilization at body temperature (e.g., above 35oC). As used herein, the term “porogen” refers to a substance used to create a porous structure in materials (e.g., polymers and biomaterials). Porogens can be inorganic (e.g., ammonium carbonate, calcium carbonate, ammonium bicarbonate and ammonium chloride, etc.) and organic (e.g., sawdust, shell powder, starch, polystyrene, water-soluble polymers such as PEG, Polyvinyl pyrrolidone (PVP), Polyvinylalcohol (PVA), Polymethaacrylate (PMA), Polyacrylicacid (PAA), etc.)).Atty. Docket No. UM-42565.601As used herein, the term “porous” refers to the characteristic of a material or object having pores or minute spaces or holes through which liquids and other molecules may pass. The “porosity” of a material or object refers to the allowance of the uptake of liquid and of analytes present in the liquid into a porous particle (e.g., through or into the space provided for by the pores) and may be described in relation to the type or size of molecules that may pass through the pores (e.g., porous to small molecules, porous to macromolecules, etc.). As used herein, the term “hydrogel” refers to a three-dimensional polymeric structure that is insoluble or minimally soluble in water or other aqueous solutions but which is capable of absorbing and retaining water or other aqueous solutions from the adjacent environment while remaining a stable structure. A hydrogel is typically formed when an organic polymer (natural or synthetic) is cross-linked via covalent, ionic, or hydrogen bonds to create a three-dimensional open-lattice structure that entraps water molecules to form a gel. In some embodiments, the hydrogels are biodegradable (e.g., by proteolytic degradation mechanisms present in the natural extracellular matrix (ECM)). As used herein, the term “biocompatible hydrogel” refers to a polymer that forms a gel that is not toxic to living cells and allows sufficient diffusion of oxygen and nutrients to entrapped cells to maintain viability. As used herein, the term “biocompatible” generally refers to a material and any metabolites or degradation products thereof that are generally non-toxic to the recipient and do not cause any significant adverse effects to the subject. As used herein, the term “biological material” refers to a cell, tissue, or organ. As used herein, the term “immunoisolation” or “immune isolation” refers to a strategy used to protect a therapeutic, such as implanted cells or tissue, from being rejected by a donor. Immunoisolation strategies include use of semipermeable membranes, microencapsulation, and macroencapsulation technologies to provide for the diffusion of nutrients and small molecules, while preventing free exchange of cells. In some embodiments, the strategy includes providing a barrier around an implanted cell or tissue, wherein the barrier allows for the passage of nutrients and oxygen into the implanted cell or tissue and allows waste products to move away from the implanted cell or tissue, but prevents the passage of immune cells and antibodies to contact the implanted cell or tissue. TheAtty. Docket No. UM-42565.601passage of nutrients and oxygen into the implanted cell or tissue supports the survival of the implanted cell or tissue, while the prevention of the passage of immune cells and antibodies into the implanted cell or tissue eliminates or minimizes the rejection of the implanted cells or tissue by the host immune system. Immunoisolation of implanted cells or tissue allows foreign grafts to survive for extended, often indefinite, intervals. As used herein, the term “immunoisolation device” refers to a device that prevents, eliminates, and / or minimizes rejection of a graft and / or to prevent, eliminate, and / or minimize the risk of disease transmission. In some embodiments the immunoisolation device comprises a degradable inner core comprising a biological material and a non-degradable outer shell encapsulating the degradable inner core and comprising a thermosensitive gelatin microgel. In some embodiments the immunoisolation device comprises a degradable inner core comprising a biological material and a non-degradable outer shell encapsulating the degradable inner core and comprising a number of pores. As used herein, the term “dual layer” refers to two layers of a hydrogel (e.g., an “outer shell” and an “inner core”). For example, an outer shell of an immunoisolation device is prepared with a non-degradable (ND) substance (e.g., a non- degradable hydrogel) and an inner core is prepared with a degradable substance (e.g., a degradable hydrogel). As used herein, the term “polypeptide” includes proteins and fragments thereof (e.g., peptides). In some embodiments, polypeptides are disclosed as amino acid residue (or monomer) sequences. Those sequences are written left to right in the direction from the amino to the carboxy terminus. In accordance with standard nomenclature, amino acid residue sequences are denominated using either a three letter code or a single letter code as indicated as follows: Alanine (Ala, A), Arginine (Arg, R), Asparagine (Asn, N), Aspartic Acid (Asp, D), Cysteine (Cys, C), Glutamine (Gln, Q), Glutamic Acid (Glu, E), Glycine (Gly, G), Histidine (His, H), Isoleucine (Ile, I), Leucine (Leu, L), Lysine (Lys, K), Methionine (Met, M), Phenylalanine (Phe, F), Proline (Pro, P), Serine (Ser, S), Threonine (Thr, T), Tryptophan (Trp, W), Tyrosine (Tyr, Y), and Valine (Val, V). In addition, a polypeptide can include non-standard and / or non-naturally occurring amino acids or post- translationally modified amino acids such as hydroxylated amino acids, as well as other amino acids that may be found in phosphorylated proteins in organisms such as, but notAtty. Docket No. UM-42565.601limited to, animals, plants, insects, protists, fungi, bacteria, algae, single-cell organisms, and the like. The non-standard amino acids include, but are not limited to, selenocysteine, selenomethionine, pyrrolysine, gamma-aminobutyric acid, carnitine, ornithine, citrulline, homocysteine, hydroxyproline, hydroxylysine, sarcosine, and the like. The non-naturally occurring amino acids include, but are not limited to, trans-3-methylproline, 2,4- methanoproline, cis-4-hydroxyproline, trans-4-hydroxyproline, N-methylglycine or other N- substituted glycines, beta-amino acids, allo-threonine, methylthreonine, hydroxyethylcysteine, hydroxyethylhomocysteine, nitro-glutamine, homoglutamine, pipecolic acid, thiazolidine carboxylic acid, dehydroproline, 3- and 4-methylproline, 3,3- dimethylproline, tert-leucine, norvaline, 2-azaphenylalanine, 3-azaphenylalanine, 4- azaphenylalanine, and 4-fluorophenylalanine. As used herein, the term “attached” or the phrases “interacts with” and “associated with” refers to a stable physical, biological, biochemical, and / or chemical association. In general, association can be chemical bonding (e.g., covalently or ionically), a biological interaction, a biochemical interaction, and in some instances a physical interaction including a specific binding interaction between biological molecules. The association can comprise a number of covalent bonds, non-covalent bonds, ionic bonds, metal ion chelation interactions, as well as moieties being linked through interactions such as, but not limited to, hydrophobic interactions, hydrophilic interactions such as hydrogel bonding, hydrogen bonding, charge- charge interactions, π-stacking interactions, combinations thereof, and like interactions. The term “cancer”, as used herein, shall be given its ordinary meaning, as a general term for diseases in which abnormal cells divide without control and form cancer or neoplastic cells, tissues, or tumors. The term cancer can include cancer cells and / or precancerous cells. In particular, and in the context of some embodiments of the present disclosure, cancer refers to ovarian cancer and cancers of the female reproductive organs and system. Cancer cells can invade nearby tissues and can spread through the bloodstream and lymphatic system to other parts of the body. There are several main types of cancer, for example, carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such asAtty. Docket No. UM-42565.601the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the bloodstream. Lymphoma is cancer that begins in the cells of the immune system. When normal cells lose their ability to behave as a specified, controlled, and coordinated unit, a tumor may be formed. Generally, a solid tumor is an abnormal mass of tissue that usually does not contain cysts or liquid areas (although some brain tumors do have cysts and central necrotic areas filled with liquid). A single tumor may even have different populations of cells within it, with differing processes that have gone awry. Solid tumors may be benign (not cancerous) or malignant (cancerous). Different types of solid tumors are named for the type of cells that form them. Examples of solid tumors are sarcomas, carcinomas, and lymphomas. Leukemias (cancers of the blood) generally do not form solid tumors. Representative cancers include, but are not limited to, bladder cancer, breast cancer, colorectal cancer, endometrial cancer, head and neck cancer, leukemia, lung cancer, lymphoma, melanoma, non-small-cell lung cancer, ovarian cancer, prostate cancer, testicular cancer, uterine cancer, cervical cancer, thyroid cancer, gastric cancer, brain stem glioma, cerebellar astrocytoma, cerebral astrocytoma, glioblastoma, ependymoma, Ewing’s sarcoma family of tumors, germ cell tumor, extracranial cancer, Hodgkin’s disease, leukemia, acute lymphoblastic leukemia, acute myeloid leukemia, liver cancer, medulloblastoma, neuroblastoma, brain tumors generally, non-Hodgkin’s lymphoma, osteosarcoma, malignant fibrous histiocytoma of bone, retinoblastoma, rhabdomyosarcoma, soft tissue sarcomas generally, supratentorial primitive neuroectodermal and pineal tumors, visual pathway and hypothalamic glioma, Wilms’s tumor, acute lymphocytic leukemia, adult acute myeloid leukemia, adult non-Hodgkin’s lymphoma, chronic lymphocytic leukemia, chronic myeloid leukemia, esophageal cancer, hairy cell leukemia, kidney cancer, multiple myeloma, oral cancer, pancreatic cancer, primary central nervous system lymphoma, skin cancer, small-cell lung cancer, among others. A tumor can be classified as malignant or benign. In both cases, there is an abnormal aggregation and proliferation of cells. In the case of a malignant tumor, these cells behave more aggressively, acquiring properties of increased invasiveness. Ultimately, the tumor cells may even gain the ability to break away from the microscopic environment inAtty. Docket No. UM-42565.601which they originated, spread to another area of the body (with a very different environment, not normally conducive to their growth), and continue their rapid growth and division in this new location. This is called metastasis. Once malignant cells have metastasized, achieving a cure is more difficult. Benign tumors have less of a tendency to invade and are less likely to metastasize. As used herein, phosphate buffered saline, abbreviated “PBS”, and Dulbecco’s phosphate buffered saline, abbreviated “DPBS,” are buffered saline solutions used in biological studies. PBS and DPBS are used in research involving cells. The ion concentration and osmolarity of PBS and DPBS are isotonic, that is, compatible with the human body. In some embodiments, these buffers provide and preserve a stable pH of 7.2-7.6. There is no significant difference between PBS and DPBS. Both of them contain sodium phosphate, sodium chloride, and, when required, potassium phosphate and potassium chloride. In some embodiments, preparations of PBS or DPBS may or may not contain calcium and magnesium. PBS and DPBS have numerous applications because they are not noxious to cells. Both PBS and DPBS can be used to rinse instruments or containers. Also, both of them can be used in diluting substances. As used herein, the terms “degradable” and “biodegradable” generally refer to a material that degrades or erodes by hydrolysis or enzymatic action under physiologic conditions to smaller units or chemical species that are capable of being metabolized, eliminated, or excreted by the subject. As used herein, the “degradation rate” refers to a rate relating the number of smaller units or chemical species that are produced by biodegradation or degradation of a material as a function of time. As used herein, the “degradation time” refers to the time required to produce a threshold number of smaller units or chemical species by biodegradation or degradation of a material and is a function of polymer composition and morphology. As used herein, the term “non-degradable” refers to a material that is not “degradable” or that is substantially or effectively less degradable than a degradable material (e.g., has a substantially or effectively lower degradation rate or a substantially or effectively longer degradation time).Atty. Docket No. UM-42565.601As used herein, the term “mammalian cell” refers to any cell derived from a mammalian subject suitable for transplantation into the same or a different subject. The cell may be syngeneic, xenogeneic, autologous, or allogeneic. The cell can be a primary cell obtained directly from a mammalian subject. The cell may also be a cell derived from the culture and expansion of a cell obtained from a subject. For example, the cell may be a stem cell. Immortalized cells are also included within this definition. In some embodiments, the cell has been genetically engineered to express a recombinant protein and / or nucleic acid. As used herein, the term “transplant” refers to the transfer of a cell, tissue, or organ to a subject from another source. The term is not limited to a particular mode of transfer. Encapsulated cells may be transplanted by any suitable method, such as by injection or surgical implantation. As used herein, the term “autologous” refers to a transplanted biological substance taken from the same individual. As used herein, the term “xenogeneic” refers to a transplanted biological substance taken from a different species. As used herein, the term “xenogeneic transplantation” refers to the transplantation of living cells, tissues, or organs from one species to another. Such cells, tissues, or organs are called “xenografts” or “xenotransplants”. Both allotransplantation (e.g., a same-species transplant) and xenotransplantation can cause rejection of the graft because the immune system of the host recognizes the transplant as foreign (e.g., as “non-self”). In addition to rejection, disease transmission (“xenozoonosis”) and permanent alteration to the host genetic code are causes for concern. Accordingly, the use of immunoisolating devices provides a technology to prevent, eliminate, and / or minimize rejection of a graft and / or to prevent, eliminate, and / or minimize the risk of disease transmission. As used herein, the term “allogeneic” refers to a transplanted biological substance taken from a different individual of the same species. Accordingly, as used herein, the term “allogeneic transplantation” or “allotransplantation” refers to the transplantation (e.g., of a cell, tissue, or organ) to a recipient from a genetically non-identical donor of the same species. The transplant is called an allograft, allogeneic transplant, or homograft. Most human tissue and organ transplants are allografts because humans genetically differ from each other. Similarly, transplantation of a tissue between different strains of mice is termed an allogeneicAtty. Docket No. UM-42565.601transplantation. An immune response against an allograft, termed rejection, will arise in healthy individuals without immune suppression. As used herein, the term “isogeneic transplantation” or “syngraft” is a graft between genetically identical individuals, typically between identical twins or between animals of a single highly inbred strain. This type of graft typically does not provoke the immune system and does not cause rejection. As used herein, the term “endocrine system” refers to the collection of cells and tissues of an organism that secrete hormones directly into the blood to control physiological and behavioral activities of the organism. The endocrine system comprises a series of glands that produce molecules called hormones. A number of glands that signal to each other in a sequence are usually referred to as an axis, for example, the hypothalamic-pituitary-gonadal (HPG) axis that in a female connects the glands involved in regulating the ovarian function. Reproductive endocrine function is mediated by sex hormones, such as estradiol and progesterone. Besides the effect of the sex hormones on the reproductive organ, they have other functions, such as metabolism, fat storage, blood vessel and skin maintenance, protein synthesis, prevention of bone resorption, and muscle degeneration. As used herein, the term “endogenous” as it relates to an organism or biological system refers to a substance, molecule, etc. produced or synthesized within the organism or biological system. As used herein, the term “endogenous hormones” as it relates to an organism or biological system refers to hormones produced or synthesized within the organism or biological system. For example, in females estradiol is produced in special structures called ovarian follicles. Follicles produce estradiol in response to other hormones that regulate ovarian function. As used herein, the terms “epiphyses” and “epiphyseal growth plate” refer to features of a bone. Bone is a living tissue comprising a protein (collagen) matrix upon which calcium salts are deposited. A growing bone is described by the ends, or epiphyses, and the shaft. The portion of each epiphysis in contact with the shaft is a plate of actively proliferating cartilage (connective tissue composed of collagen and other fibrous proteins) called the epiphyseal growth plate. Linear growth of the shaft can continue as long as theAtty. Docket No. UM-42565.601epiphyseal growth plates exist but cease when the growth plates are converted to bone as a result of hormonal influences at puberty. This is known as epiphyseal closure and occurs at different times in different bones. As used herein, the term “estrogen” refers to a class of steroid hormones secreted by the ovaries. For example, estradiol is a predominant estrogen in the plasma. Estradiol is produced and secreted from ovaries and it plays a key role in puberty, providing a hormonal milieu for physical and psychosocial development. Estradiol is responsible for the development of the female appearance, bone growth, and brain development. Simultaneously, increases in estradiol levels during puberty stimulate other growth hormones that lead to the pubertal growth spurt. The hypothalamus, pituitary gland, and the ovary interact along the “HPG axis”. The pulsatile release of Gonadotropin Releasing Hormone (GnRH) from the hypothalamus stimulates the secretion of Luteinizing hormone (LH) and Follicle stimulating hormone (FSH) from the pituitary gland in the brain. FSH directly stimulates granulosa cells in the growing follicles to secrete estradiol. LH stimulates theca cells in the follicle to produce precursors of estradiol to increase its production. HPG axis is a loop that is tightly regulated by the secreted hormones. As used herein, the term “exogenous” as it relates to an organism or biological system refers to a substance, molecule, etc. originating from outside an organism or biological system. As used herein, the term “exogenous hormone” as it relates to an organism or biological system refers to a hormone originating from outside the organism or biological system. Exogenous estrogen is a synthetic analog of the estradiol and can mimic the function of endogenous estradiol. As used herein, the term “follicle” or “ovarian follicle” refers to the functional unit of the ovary. It contains a germ cell that is future to develop into an egg, surrounded by multiple layers of supportive cells, called granulosa cells. In the ovaries, granulosa cells synthesize and secrete estradiol in response to the hormones that control the ovarian function. Theca cells build the outside layer of the follicle. Theca cells produce androgens, which are the precursors for estradiol produced by granulosa cells.Atty. Docket No. UM-42565.601As used herein, the term “follicular stimulating hormone”, abbreviated “FSH”, refers to a hormone that is secreted from the pituitary gland as a result of hypothalamus stimulation. FSH acts on ovaries and stimulates estradiol secretion and follicle growth. As used herein, the term “folliculogenesis” refers to a process that describes the maturation of the ovarian follicle, a densely packed shell of somatic cells that surround a germ cell. Folliculogenesis describes the progression of small immature follicles to a mature follicle ready for ovulation. Hormones secreted from hypothalamus (GnRH) and pituitary gland (FSH and LH) regulate the process of follicle development. In response to hormonal stimulation follicles produce estradiol and progesterone that regulate the hormone production in the brain in a series of positive and negative feedback mechanisms. The levels of all hormones in the HPG axis cyclically fluctuate. As used herein, the term “gamete” refers to a cell that fuses with another cell during fertilization in organisms that reproduce sexually. In a female, the gamete is often referred to as an “egg”. As used herein, the term “germ cell” refers to a cell that gives rise to a female gamete (egg) or a male gamete (sperm). As used herein, the term “hormone” refers to a substance (e.g., a bioactive substance) released from endocrine tissue into the bloodstream where it travels to a target tissue to generate a response. Hormones regulate various human functions, including metabolism, growth and development, tissue function, sleep, and mood. The term hormone as used herein also encompasses natural or synthetic molecules having the same or similar bioactive properties as a hormone released by endocrine tissue; and encompasses derivatives of natural and synthetic hormones and natural and synthetic molecules having the same or similar bioactive properties as a hormone released by endocrine tissue. As used herein, the term “gonadotropin releasing hormone”, abbreviated “GnRH”, is the first hormone in the axis between hypothalamus, pituitary gland, and ovary. GnRH stimulates the secretion of the hormones from the pituitary gland (FSH and LH), which in turn control the ovarian function.Atty. Docket No. UM-42565.601As used herein, the term “in vitro” refers to an environment outside a living organism. In science this term refers to experiments performed in an artificial or synthetic environment. As used herein, the term “in vivo” refers to within a living organism. In science this term refers to experiments performed in an animal model or in humans. As used herein, the term “luteinizing hormone”, abbreviated “LH” refers to a hormone that is secreted from the pituitary gland as a result of hypothalamus stimulation. LH acts on theca cells in the follicles to stimulate the production of the precursors of estradiol. As used herein, the term “primordial follicles” refers to immature and undeveloped stage of the follicles. These follicles contain one germ cell, which is surrounded by several somatic cells. The primordial follicles constitute the majority of the ovarian reserve at any age. As used herein, the term “thrombosis” refers to the formation of a blood clot (“thrombus”) inside a blood vessel, obstructing the flow of blood through the circulatory system. When a thrombus is significantly large enough to reduce the blood flow to a tissue, oxygen deprivation can occur and metabolic products can accumulate. A larger thrombus causing a much greater obstruction to the blood flow may result in anoxia, the complete deprivation of oxygen and tissue death. As used herein, the term “biological communication” refers to the ability of a biological component to communicate with another biological component, e.g., by exchange of communicating substances such as metabolites, catabolites, proteins, nucleic acids, small molecules (e.g., hormones), lipids, etc. with the biological component. A first biological component in biological communication with a second biological component is exposed to communicating substances produced and / or secreted by the second biological component. As used herein, a “biological component” is not limited by size or scale and thus may be a molecule, biological structure, organelle, cell, tissue, organ, system, or organism. The terms “administration of” and “administering” a composition as used herein refers to providing a composition of the present disclosure to a subject in need of treatment (e.g., antiviral treatment). The compositions of the present disclosure may be administered by oral, parenteral (e.g., intramuscular, intraperitoneal, intravenous, ICV, intracisternal injectionAtty. Docket No. UM-42565.601or infusion, subcutaneous injection, nebulization, or implant), by inhalation spray, nasal, vaginal, rectal, sublingual, or topical routes of administration and may be formulated, alone or together, in suitable dosage unit formulations containing conventional non-toxic pharmaceutically acceptable carriers, adjuvants and vehicles appropriate for each route of administration. The term “composition” as used herein refers to a product comprising the specified ingredients in the specified amounts, as well as any product which results, directly or indirectly, from combination of the specified ingredients in the specified amounts. Such a term in relation to a “pharmaceutical composition”, as the term is used herein, is intended to encompass a product comprising the active ingredient(s), and the inert ingredient(s) that make up the carrier, as well as any product which results, directly or indirectly, from combination, complexation, or aggregation of any two or more of the ingredients, or from dissociation of one or more of the ingredients, or from other types of reactions or interactions of one or more of the ingredients. Accordingly, pharmaceutical compositions of the present disclosure encompass any composition made by admixing a compound of the present disclosure and a pharmaceutically acceptable carrier and / or excipient. When a compound of the present disclosure is used contemporaneously with one or more other drugs, a pharmaceutical composition containing such other drugs in addition to the compound of the present disclosure is contemplated. Accordingly, the pharmaceutical compositions of the present disclosure include those that also contain one or more other active ingredients, in addition to a compound of the present disclosure. The weight ratio of the compound of the present disclosure to the second active ingredient may be varied and will depend upon the effective dose of each ingredient. Generally, an effective dose of each will be used. Combinations of a compound of the present disclosure and other active ingredients will generally also be within the aforementioned range, but in each case, an effective dose of each active ingredient should be used. In such combinations the compound of the present disclosure and other active agents may be administered separately or in conjunction. In addition, the administration of one element may be prior to, concurrent to, or subsequent to the administration of other agent(s). As used herein, the term “subject” and “patient” as used herein interchangeably refers to any vertebrate, including, but not limited to, a mammal (e.g., cow, pig, camel, llama,Atty. Docket No. UM-42565.601horse, goat, rabbit, sheep, hamsters, guinea pig, cat, dog, rat, and mouse, a non-human primate (e.g., a monkey, such as a cynomolgus or rhesus monkey, chimpanzee, macaque, etc.) and a human). In some embodiments, the subject may be a human or a non-human. In one embodiment, the subject is a human. The subject or patient may be undergoing various forms of treatment. For veterinary applications, a wide variety of subjects is suitable, e.g., livestock such as cattle, sheep, goats, cows, swine, and the like; poultry such as chickens, ducks, geese, turkeys, and the like; and domesticated animals particularly pets such as dogs and cats. For diagnostic or research applications, a wide variety of mammals will be suitable subjects, including rodents (e.g., mice, rats, hamsters), rabbits, primates, and swine such as inbred pigs and the like. As used herein, the term “treat,” “treating” or “treatment” are each used interchangeably herein to describe reversing, alleviating, or inhibiting the progress of a disease and / or injury, or one or more symptoms of such disease, to which such term applies. Depending on the condition of the subject, the term also refers to preventing a disease, and includes preventing the onset of a disease, or preventing the symptoms associated with a disease (e.g., viral infection). A treatment may be either performed in an acute or chronic way. The term also refers to reducing the severity of a disease or symptoms associated with such disease prior to affliction with the disease. Such prevention or reduction of the severity of a disease prior to affliction refers to administration of a treatment to a subject that is not at the time of administration afflicted with the disease. “Preventing” also refers to preventing the recurrence of a disease or of one or more symptoms associated with such disease. “Treatment,” as used herein, covers any treatment of a disease, disorder, or condition in a host (e.g., a mammal, typically a human or non-human animal of veterinary interest), and includes: (a) reducing the risk of occurrence of a disease, disorder, or condition in a subject determined to be predisposed to the disease, disorder, or condition, but not yet diagnosed as having the disease, disorder, or condition; (b) impeding the development of a disease, disorder, or condition; (c) relieving a disease, disorder, or condition, e.g., causing regression of the disease, disorder, or condition and / or relieving one or more symptoms of the disease, disorder, or condition; (d) ameliorating, reducing, or reversing one or more symptoms of a disease, disorder, or condition and / or ameliorating, reducing, or reversing oneAtty. Docket No. UM-42565.601or more symptoms resulting from a treatment for the disease, disorder, or condition; and (e) providing or restoring normal (or near normal, adequate, sufficient, essentially normal, and / or effectively normal) or improved biological processes in a subject, e.g., a subject who has impaired or damaged biological processes due to a disease, disorder, or condition and / or from treatment of a disease, disorder, or condition. “Treatment” is also meant to encompass providing a pharmacologic effect in a normal subject or in a subject in the absence of a disease, disorder, or condition. For example, “treatment” encompasses providing for improved, enhanced, or desirable effects in the subject (e.g., reduction of tumor load, reduction of symptoms, improved or normal growth and development, extension of a period of a patient’s apparent, functional health, etc.). As used herein, the terms “prophylactically treat” or “prophylactically treating” refers to completely or partially preventing a disease or symptom thereof and / or may be therapeutic in terms of a partial or complete cure for a disease and / or adverse effect attributable to the disease. As used herein, the term “microfluidics” refers to the behavior of fluids through micro-channels and the technology of microminiaturized devices containing chambers and tunnels through which fluids flow or are confined. As used herein, the term “microfluidic device” refers to any instrument that uses microfluidics to perform certain laboratory functions. In some embodiments, microfluidic devices have multiphase flows which use segmented streams of two or more immiscible phases. In some embodiments, the interaction between immiscible phases combined with applied force results in a flow characterized by streams that can be segmented into bubbly, slug or Taylor, churn, annular, and slug-annular profiles. In some embodiments, the flow pattern is a segmented flow (e.g., Taylor flow), which is characterized by droplets surrounded by liquid. Unless otherwise defined herein, scientific and technical terms used in connection with the present disclosure shall have the meanings that are commonly understood by those of ordinary skill in the art. For example, any nomenclatures used in connection with, and techniques of, cell and tissue culture, molecular biology, immunology, microbiology, genetics and protein and nucleic acid chemistry and hybridization described herein are those that areAtty. Docket No. UM-42565.601well known and commonly used in the art. The meaning and scope of the terms should be clear; in the event, however of any latent ambiguity, definitions provided herein take precedent over any dictionary or extrinsic definition. Further, unless otherwise required by context, singular terms shall include pluralities and plural terms shall include the singular. 2. Compositions Embodiments of the present disclosure include compositions comprising an immunoisolation device comprising a degradable inner core comprising a biological material and a non-degradable outer shell encapsulating the degradable inner core and comprising a thermosensitive gelatin microgel. In some embodiments, the immunoisolation device finds use in improving and / or restoring ovarian endocrine function and controlling host immunity (e.g., to restore ovarian endocrine function, (e.g., in young women with premature ovarian failure (POF))). This technology (e.g., an immunoisolation device) allows the cells to exchange hormones, metabolites, catabolites, and other biologically active substances (except immune components) with the body of the subject, but protects the transplanted cells from immune recognition and immune rejection by the subject. The technology also allows waste products produced by the biological material to move away from the biological material. In some embodiments, the immunoisolation device is adapted for the particular characteristics of certain tissue types (e.g., ovarian tissue) and / or comprises well- characterized biomaterials. In some embodiments (e.g., embodiments associated with treating a female endocrine deficiency), the immunoisolation device further comprises estrogen and / or progesterone produced by the cells. In some embodiments, the immunoisolation device further comprises a drug (e.g., an immunosuppressive drug). In some embodiments, the immunoisolation device comprises polyvinylpyrrolidone. Embodiments of the present disclosure are not limited in the types of biological material provided in the inner core. For example, in some embodiments, the immunoisolation device comprises a cell, tissue, or organ. In some embodiments, the biological material comprises cells that are from an endocrine organ (e.g., from an ovary). In some embodiments, the immunoisolation deviceAtty. Docket No. UM-42565.601comprises use of donor ovarian tissue encapsulated in the immunoisolation device. In some embodiments, the biological material comprises ovarian follicles, germ cells, and / or somatic cells. In some embodiments, the biological material comprises a differentiated stem cell or is genetically engineered. Further, the immunoisolation device is not limited in the materials that are used to produce the inner core and the outer shell. Embodiments contemplate various types of crosslinking of the inner core and outer shell; in some embodiments, the degradable inner core comprises a polyethylene glycol crosslinked with a degradable peptide (e.g., a degradable peptide comprising a matrix-metalloproteinase (MMP) sensitive sequence and / or a plasmin sensitive sequence). In some embodiments, the inner core and / or the outer shell comprises a polyethylene glycol hydrogel (e.g., a polyethylene glycol vinyl sulfone hydrogel (e.g., a photo-polymerized polyethylene glycol vinyl sulfone)). In some embodiments, semisolid hydrogels find use. In some embodiments, the immunoisolation device is a hydrogel, a dual layer hydrogel, a biocompatible hydrogel, a dual layer PEG hydrogel, a biocompatible dual layer PEG hydrogel, a dual layer PEGG+ hydrogel, or a biocompatible dual layer PEGG+ hydrogel. In some embodiments, the inner core comprises a polyethylene glycol concentration of 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%, , 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, or 15% PEG. In some embodiments, the outer shell comprises a polyethylene glycol concentration of 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%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, or 15% PEG. Some embodiments comprise use of a non-degradable PEG (e.g., PEG-maleimide (PEG-Mal)). Some embodiments comprise use of a hydrolytically-degradable PEG (e.g., PEG-acrylate (PEG-Ac)). In some embodiments, the immunoisolation device comprises hydrogels crosslinked with (or otherwise incorporating) protease sensitive peptides. Some exemplary peptide sequences having protease sensitivity are derived from collagen (e.g., matrix-metalloproteinase (MMP) sensitive sequence) and fibrin (e.g., plasmin sensitive sequences). In some embodiments, protease-sensitive peptides (e.g., comprising a matrix-metalloproteinase (MMP) sensitiveAtty. Docket No. UM-42565.601sequence or a plasmin sensitive sequence) are incorporated into PEG hydrogels for degradation of the hydrogel (e.g., by the host enzyme activities). In sum, hydrogels provide a three-dimensional environment for the encapsulated cells or tissues (e.g., ovarian follicles), which promotes follicle function and survival in the immunoisolation device. Some embodiments comprise use of a peptide that is a plasmin sensitive peptide (e.g., for use as a degradable cross-linker in some embodiments of the technology). Some embodiments comprise use of a peptide (e.g., a plasmin-sensitive peptide) that has the amino acid sequence: Ac-GCYK↓NSGCYK↓NSCG (SEQ ID NO: 1) In the amino acid sequence of the plasmin sensitive peptide, the N-terminal acetyl group is added to remove the electrical charge on this terminal. The arrows indicate the protease cleavage sites. That is, embodiments comprise use of a peptide that has an amino acid sequence according to: GCYKNSGCYKNSCG (SEQ ID NO: 2) with an N-terminal acetyl group and that is cleaved by a protease (e.g., plasmin) between lysine and asparagine in the sequence, e.g., after the lysine at position 4 and / or after the lysine at position 10. Some embodiments comprise use of a peptide that is sensitive to both plasmin and MMP proteases (e.g., for use as a degradable cross-linker in some embodiments of the technology). Some embodiments comprise use of a peptide (e.g., a peptide that is both plasmin-sensitive and MMP-sensitive) that has the amino acid sequence: GCRDVPMS↓MRGGDRCGYK↓NSCG (SEQ ID NO: 3) In the amino acid sequence of the peptide that is both plasmin-sensitive and MMP- sensitive, the arrows indicate the protease cleavage sites. That is, embodiments comprise use of a peptide that has an amino acid sequence according to: GCRDVPMSMRGGDRCGYKNSCG (SEQ ID NO: 4) that is cleaved by a protease (e.g., plasmin and / or MMP) between serine and methionine in the sequence at positions 8 and 9 and / or between the lysine and asparagine in the sequence at positions 18 and 19. This peptide sequence is sensitive to MMP and plasmin proteases and thus presents aAtty. Docket No. UM-42565.601degradable cross-linker for encapsulated tissue and that finds use with several tissue types (e.g., tissues that comprise one or both of a plasmin and / or MMP protease). In some embodiments, the immunoisolation device comprises an inert and durable pouch comprising a semipermeable membrane system. In some embodiments, the immunoisolation device comprises an inner core configured to allow the cells to grow (e.g., the inner core of the immunoisolation device is a degradable multi-arm (e.g., 8-arm) PEG hydrogel, crosslinked with peptides, that degrades as ovarian follicles grow). Exposure to the circulating gonadotropins in ovariectomized hosts stimulates follicle growth and hormone secretion and mimicks the physiological feedback between multiple organs and tissues involved in pubertal development. In some embodiments, the degradable inner core comprises a polyethylene glycol hydrogel. In some embodiments, the degradable inner core comprises a polyethylene glycol crosslinked with a degradable peptide. In some embodiments, the outer shell of the immunoisolation device comprises a mixture of PEG and gelatin microgels. In some embodiments, the outer shell of the immunoisolation device comprises porogens (e.g., a substance used to create a porous structure in a materials (e.g., a polymer or a biomaterial)). In some embodiments, the porogens are inorganic (e.g., ammonium carbonate, calcium carbonate, ammonium bicarbonate and ammonium chloride, etc.) or organic (e.g., sawdust, shell powder, starch, polystyrene, water-soluble polymers such as PEG, Polyvinyl pyrrolidone (PVP), Polyvinylalcohol (PVA), Polymethaacrylate (PMA), Polyacrylicacid (PAA), etc.)). In some embodiments, the porogens are about 5 µm in diameter, 10 µm in diameter, 15 µm in diameter, 20 µm in diameter, 25 µm in diameter, 30 µm in diameter, 35 µm in diameter, 40 µm in diameter, 45 µm in diameter, 50 µm in diameter, 55 µm in diameter, 60 µm in diameter, 65 µm in diameter, 70 µm in diameter, 75 µm in diameter, 80 µm in diameter, 85 µm in diameter, 90 µm in diameter, 95 µm in diameter, or 100 µm in diameter. In some embodiments, the porogens are thermosensitive such that they melt (e.g., at a temperature of about 35°C to 37°C) to produce pores. In some embodiments, the pores facilitate oxygenation and nutrition to an encapsulated tissue. In some embodiments, theAtty. Docket No. UM-42565.601nanoporous nature of the immunoisolation device enables bidirectional exchange of soluble factors and prevents interaction of the immune system with the biological material (e.g., ovarian tissue). In some embodiments, the outer shell of the immunoisolation device is configured to allow exchange of metabolites with the environment outside the immunoisolation device and to protect an encapsulated cell (e.g., encapsulated by the inner core of the immunoisolation device) from immune recognition by the host immune system components outside the immunoisolation device. In some embodiments, the porogens are microgels. In some embodiments, the microgels comprise one or more microscopic solid particles that are suspended in a fluid and form a network structure that consists of chemically cross-linked three-dimensional polymer networks. In some embodiments, the microgels are able to swell or shrink in response to external stimuli (e.g., temperature, pH, ionic strength, electric field, and enzyme activities). In some embodiments, the microgels are gelatin microgels (e.g., porcine skin gelatin). In some embodiments, the gelatin microgels are about 5 µm in diameter, 10 µm in diameter, 15 µm in diameter, 20 µm in diameter, 25 µm in diameter, 30 µm in diameter, 35 µm in diameter, 40 µm in diameter, 45 µm in diameter, 50 µm in diameter, 55 µm in diameter, 60 µm in diameter, 65 µm in diameter, 70 µm in diameter, 75 µm in diameter, 80 µm in diameter, 85 µm in diameter, 90 µm in diameter, 95 µm in diameter, or 100 µm in diameter. In some embodiments, the gelatin microgels are thermosensitive. In some embodiments, the gelatin undergoes thermoreversible crosslinking at cool temperatures (e.g., below 35oC) and solubilization at body temperature (e.g., above 35oC). In some embodiments, the gelatin microgels melt at temperatures at or above 37°C. In some embodiments, the gelatin microgels melt when implanted into a subject (e.g., a human). In some embodiments, heating the immunoisolation device enables a melting of the gelatin microgels and a diffusion out of the outer shell, wherein the porosity of the outer shell is increased. In some embodiments, the resulting pores (e.g., the pores in the outer shell) are about 5 µm in diameter, 10 µm in diameter, 15 µm in diameter, 20 µm in diameter, 25 µm in diameter, 30 µm in diameter, 35 µm in diameter, 40 µm in diameter, 45 µm in diameter, 50 µm in diameter, 55 µm in diameter, 60 µmAtty. Docket No. UM-42565.601in diameter, 65 µm in diameter, 70 µm in diameter, 75 µm in diameter, 80 µm in diameter, 85 µm in diameter, 90 µm in diameter, 95 µm in diameter, or 100 µm in diameter. In some embodiments, the gelatin microgels are spaced at suitable distances throughout the outer shell (e.g., are spaced wherein the gelatin microgels do not clump and / or cluster). In some embodiments, the gelatin microgels do not create and / or result in (e.g., at temperatures above 35oC (e.g., upon heating)) an interconnected network of pores. In some embodiments, the outer shell comprises about 50 to 250 pores per square nanometer. In some embodiments, the porosity of the outer shell enables diffusion of small (e.g., 1 kDA – 14 kDA) molecules when the outer shell comprises a concentration of about 5% v / v gelatin microgel and about 5% w / v PEG. In some embodiments, the porosity of the outer shell enables diffusion of mid-size (15 kDA – 50 kDA) molecules (e.g., proteins (e.g., peptide hormones (e.g., follicle stimulating hormone (FSH) and luteinizing hormone (LH))) when the outer shell comprises a concentration of about 10% v / v gelatin microgel and about 5% w / v PEG. In some embodiments, the porosity of the outer shell does not hinder the immune isolating function of the immunoisolation device. In some embodiments, the outer shell comprises a concentration of 1% w / v PEG, 5% w / v PEG, 10% w / v PEG, 15% w / v PEG, 20% w / v PEG, or 25% w / v PEG. In some embodiments, the outer shell comprises 5% w / v PEG mixed with gelatin microgels (e.g., the gelatin microgels are dispersed in the 5% w / v PEG (e.g., 4-arm PEG-VS dissolved in DPBS with 0.4% Irgacure 2959 and 0.1% N-vinyl-2-pyrrolidone (NVP))). In some embodiments, the outer shell comprises a concentration of 5% w / v PEG mixed with 1% v / v gelatin microgels, 1.5% v / v gelatin microgels, 2% v / v gelatin microgels, 2.5% v / v gelatin microgels, 3% v / v gelatin microgels, 3.5% v / v gelatin microgels, 4% v / v gelatin microgels, 4.5% v / v gelatin microgels, 5% v / v gelatin microgels, or 5.5% v / v gelatin microgels. In some embodiments, the outer shell comprises a concentration of 5% w / v PEG mixed with 5% v / v gelatin microgels. In some embodiments, a correct volume of gelatin microgels (e.g., correct volume of gelatin microgels to mix into the 5% w / v PEG) is calculated using a hemocytometer.Atty. Docket No. UM-42565.601In some embodiments, the gelatin microgels comprise a concentration of 1% w / v gelatin in buffer, 2% w / v gelatin in buffer, 3% w / v gelatin in buffer, 4% w / v gelatin in buffer, 5% w / v gelatin in buffer, 1.5% w / v gelatin in buffer, 2.5% w / v gelatin in buffer, 3.5% w / v gelatin in buffer, 4.5% w / v gelatin in buffer, or 5.5% w / v gelatin in buffer. In some embodiments, the gelatin microgels comprise a concentration of 2.5% w / v gelatin in buffer. In some embodiments, the buffer is Dulbecco’s Phosphate Buffered Saline (DPBS). In some embodiments, the gelatin microgel are 10 µm droplets, 15 µm droplets, 20 µm droplets, 25 µm droplets, 30 µm droplets, 35 µm droplets, 40 µm droplets, 45 µm droplets, 50 µm droplets, 55 µm droplets, 60 µm droplets, 65 µm droplets, 70 µm droplets, 75 µm droplets, 80 µm droplets, 85 µm droplets, 90 µm droplets, 95 µm droplets, or 100 µm droplets. In some embodiments, the biological material comprises at least one of ovarian follicles, germ cells, and / or somatic cells. In some embodiments, the biological material is a differentiated stem cell or is genetically engineered. 3. Methods Embodiments of the present disclosure relate to the transplant of biological material (e.g., ovarian cells) to a subject (e.g., a female cancer patient). In some embodiments, the present disclosure relates to the treatment of menopause and other conditions (e.g., a donor ovarian transplant strategy that provides delivery of natural estrogen at physiologic levels, while simultaneously reestablishing hormonal feedback regulation). In some embodiments, the present disclosure provides a clinically relevant therapy to improve or restore ovarian endocrine function (e.g., in young women and girls with POF) by improving or restoring a physiological balance of the HPG axis that exists in healthy women, which is difficult to achieve with exogenous pharmacological treatments. The present disclosure (e.g., an immunoisolation device) enables the cells to exchange hormones, metabolites, catabolites, and other biologically active substances (except immune components) with the body of the subject, and protects the transplanted cells from immune recognition and immune rejection by the subject. In some embodiments, the present disclosure provides a bioengineered matrix that supports follicle survival and function, which, in an immune privileged environment, preventsAtty. Docket No. UM-42565.601rejection by the recipient while continuing to produce estrogen and progesterone under conditions similar to normal physiologic regulation. In some embodiments, the present disclosure finds use in treating young girls who endure ovarian failure as the result of cancer treatment strategies. In some embodiments, the present disclosure provides for avoiding the deleterious effects of estrogen and progesterone deficiency and risks associated with synthetic hormonal replacement therapy, thus promoting normal development and puberty, and an otherwise healthy life. In some embodiments, the present disclosure provides a regenerative therapy employing aspects of engineering, materials, chemistry, and life sciences to create synthetic constructs to direct tissue regeneration and restoration of biological function. In some embodiments, the present disclosure provides a method of treating a subject for an endocrine deficiency comprising implanting an immunoisolation device into the subject. For example, in some embodiments the cells of the immunoisolation device produce a bioactive substance (e.g., a hormone such as estrogen and / or progesterone) for which the subject is deficient. Particular embodiments relate to treating a subject. In some embodiments, the subject is a female who was treated for a cancer of the reproductive system as a child. In some embodiments, the subject is a female who is in need of hormone therapy for menopause. In some embodiments, the present disclosure relates to an immunoisolation device comprising a synthetic membrane (e.g., a bilayer comprising an inner semipermeable membrane made of polytetrofluoroethylene (PTFE)) that is laminated to an outer membrane covered by a loose polyester mesh (e.g., commercially available as THERACYTE, TheraCyte, Inc., Laguna Hills, CA) (e.g., a "TheraCyte pouch" or a "TheraCyte bag"). For example, some embodiments relate to devices comprising cells (e.g., endocrine cells (e.g., ovarian cells)) placed in one or more synthetic membranes (e.g., for immunoisolation of the cells (e.g., for transplantation into a host)) and methods relating to transplanting the cells (e.g., endocrine cells, e.g., ovarian cells) into a subject. In some embodiments, the present disclosure provides for the survival and / or growth of transplanted cells in a subject. For example, in some embodiments the technology provides for the survival and / or growth of transplanted cells for 1 to 30 days or more (e.g., for a number of days that is 1, 2, 3, 4, 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 days, or for more than 30 days).Atty. Docket No. UM-42565.601Embodiments of the present disclosure also include methods comprising preparing an immunoisolation device, the method comprising: (a) providing a biological material, (b) providing a degradable inner core comprising the biological material; (c) incorporating a thermosensitive gelatin microgel into a non-degradable outer shell; and (d) encapsulating the degradable inner core within the non-degradable outer shell. In some embodiments, providing a degradable inner core comprising the biological material comprises implanting the biological material within the degradable inner core. In some embodiments, providing the degradable inner core comprises: (a) mixing a hydrogel solution with a protease degradable linker peptide to provide a degradable hydrogel precursor solution; (b) cross-linking the degradable hydrogel precursor solution to provide an inner core comprising a degradable hydrogel; and (c) implanting the biological material in the inner core. In some embodiments, providing a degradable hydrogel precursor solution comprises providing a photo-polymerizable and / or photo-polymerized PEG vinyl sulfone system. In some embodiments, providing a non-degradable PEG vinyl sulfone system comprises providing a solution comprising 5% PEG, 0.4% photoinitiator, and 0.1% (v / v) PVP. In some embodiments, the degradable hydrogel precursor solution comprises 0.01 to 1% photoinitiator (e.g., 0.01, 0.02, 0.03, 0.04, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5%, 0.6, 0.7, 0.8, 0.9, or 1.0% (w / v) photoinitiator). In some embodiments, a PEG precursor is irradiated (e.g., by ultraviolet light) for 1 to 10 minutes (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 minutes or more). In some embodiments, polymerization is initiated in the presence of polyvinylpyrrolidone (PVP). In some embodiments, incorporating the thermosensitive gelatin microgel into the non-degradable outer shell comprises mixing a PEG hydrogel and a microgel emulsion, wherein incorporating the thermosensitive gelatin microgel into the non-degradable outer shell comprises one or more of the following steps: (a) dissolving a thermosensitive gelatin in a first buffer to provide a thermosensitive gelatin solution; (b) running the thermosensitive gelatin solution through a droplet forming device comprising an aqueous inlet and an oil inlet that meet at a junction; (c) modulating the flow rate until a stable flow of droplets is produced and the droplets are pinched off at the junction to provide an emulsion; (d) transitioning the emulsion to an aqueous stage and storing in a second buffer; (e) adding a volume of the emulsion to aAtty. Docket No. UM-42565.601tube and centrifuging to provide a pellet comprising uniform gelatin microgels; (f) aspirating a supernatant to provide the uniform gelatin microgels; and / or (g) adding a polyethylene glycol hydrogel to the uniform gelatin microgels and mixing thoroughly to provide a polyethylene glycol hydrogel solution. In some embodiments, the buffer is Dulbecco’s Phosphate Buffered Saline (DPBS). In some embodiments, the dissolved gelatin comprises a concentration of about 1.0% w / v in the first buffer, 1.5% w / v in the first buffer, 2.0% w / v in the first buffer, 2.5% w / v in the first buffer, 3.0% w / v in the first buffer, 3.5% w / v in the first buffer, 4.0% w / v in the first buffer, 4.5% w / v in the first buffer, 5.0% w / v in the first buffer, or 5.5% w / v in the first buffer. In some embodiments, the dissolved gelatin comprise a concentration of about 2.5% w / v in the first buffer. In some embodiments, running the thermosensitive gelatin solution through a droplet forming device comprises running the thermosensitive gelatin solution through the aqueous inlet of the droplet forming device and running a fluorosurfactant solution in oil through the oil inlet of the droplet forming device. In some embodiments, the fluorosurfactant solution has a concentration of about 0.5% w / v, 1% w / v, 2% w / v, 3 % w / v, 4 % w / v, 5% w / v, 6 % w / v, 7 % w / v, 8 % w / v, 9 % w / v, 10 % w / v. In some embodiments, the stable flow of droplets produces droplets about 25 µm to 35 µm in diameter. In some embodiments, the stable flow of droplets produces droplets about 5 µm in diameter, 10 µm in diameter, 15 µm in diameter, 20 µm in diameter, 25 µm in diameter, 30 µm in diameter, 35 µm in diameter, 40 µm in diameter, 45 µm in diameter, 50 µm in diameter, 55 µm in diameter, 60 µm in diameter, 65 µm in diameter, 70 µm in diameter, 75 µm in diameter, 80 µm in diameter, 85 µm in diameter, 90 µm in diameter, 95 µm in diameter, or 100 µm in diameter. In some embodiments, the gelatin microgels comprise a concentration of about 1.0% v / v in 5% w / v PEG, 1.0% v / v in 5% w / v PEG, 1.5% v / v in 5% w / v PEG, 2.0% v / v in 5% w / v PEG, 2.5% v / v in 5% w / v PEG, 3.0% v / v in 5% w / v PEG, 3.5% v / v in 5% w / v PEG, 4.0% v / v in 5% w / v PEG, 4.5% v / v in 5% w / v PEG, 5.0% v / v in 5% w / v PEG, 5.5% v / v in 5% w / v PEG, 6.0% v / v in 5% w / v PEG, 6.5% v / v in 5% w / v PEG, 7.0% v / v in 5% w / v PEG, 7.5% v / v in 5%Atty. Docket No. UM-42565.601w / v PEG, 8.0% v / v in 5% w / v PEG, 8.5% v / v in 5% w / v PEG, 9.0% v / v in 5% w / v PEG, 9.5% v / v in 5% w / v PEG,10.0% v / v in 5% w / v PEG. In some embodiments, the gelatin microgels comprise a concentration of about 5.0% v / v in 5% w / v PEG. In some embodiments, encapsulating the degradable inner core within the non- degradable outer shell comprises (a) placing the inner core in a bead of a PEG and (b) cross- linking the PEG to form the non-degradable outer shell. In some embodiments, the inner core is configured to allow the biological material to grow. In some embodiments, suspending the biological material in a culture or maintenance medium prior to encapsulation or preserving the biological material in an environment prior to encapsulation. Embodiments of the present disclosure also include methods of treatment relating to providing a clinically relevant therapy to improve or restore ovarian endocrine function (e.g., in young women and girls with POF) by improving or restoring a physiological balance of the HPG axis that exists in healthy women, which is difficult to achieve with exogenous pharmacological treatments. In some embodiments, a method of treating a subject for an endocrine deficiency comprises implanting an immunoisolation device into the subject. In some embodiments, the subject suffers from an endocrine deficiency. In some embodiments, the biological material produces a bioactive substance for which the subject is deficient. For example, in some embodiments, the cells of the immunoisolation device produce a bioactive substance (e.g., a hormone such as estrogen and / or progesterone) for which the subject is deficient. In some embodiments, a method of treating a subject comprises treating a female subject who was treated for a cancer of the reproductive system as a child. In some embodiments, the subject is a female who is in need of hormone therapy for menopause. In some embodiments, the subject is a female who had cancer as a child, a female who has had a cytotoxic treatment, and / or a female who is in need of hormone therapy for menopause. In some embodiments, the present disclosure relates to an immunoisolation device comprising a synthetic membrane (e.g., a bilayer comprising an inner semipermeable membraneAtty. Docket No. UM-42565.601made of polytetrofluoroethylene (PTFE) that is laminated to an outer membrane covered by a loose polyester mesh (e.g., commercially available as THERACYTE, TheraCyte, Inc., Laguna Hills, CA) (e.g., a "TheraCyte pouch" or a "TheraCyte bag")). For example, some embodiments relate to devices comprising cells (e.g., endocrine cells, e.g., ovarian cells) placed in a synthetic membrane (e.g., for immunoisolation of the cells (e.g., for transplantation into a host)), and methods relating to placing cells (e.g., endocrine cells, e.g., ovarian cells) into a synthetic membrane pouch or bag and methods relating to transplanting the cells (e.g., endocrine cells, e.g., ovarian cells) in the synthetic pouch or bag into a host. In some embodiments, the present disclosure provides for the survival and / or growth of transplanted cells in a host. For example, in some embodiments the present disclosure provides for the survival and / or growth of transplanted cells for 1 to 30 days or more (e.g., for a number of days that is 1, 2, 3, 4, 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 days, or for more than 30 days). In some embodiments, a method of treating a subject comprises treating a subject who is in need of a bioactive substance, the method comprising: (a) providing an immunoisolation device comprising: (i) an inner core comprising a biological material; and (ii) a non-degradable outer shell encapsulating the inner core and comprising a thermosensitive gelatin microgel; and (b) implanting the immunoisolation device into the subject, wherein the thermosensitive gelatin microgel melts when implanted into the body. In some embodiments, the thermosensitive gelatin microgel melts when implanted into the body to provide an immunoisolation device comprising pores in the non-degradable outer shell. In some embodiments, the non-degradable outer shell comprises about 50 to 250 pores per square nanometer. In some embodiments, the pores are about 25 µm to 35 µm in diameter. 4. Kits Embodiments of the present disclosure also include kits comprising: a degradable PEG hydrogel precursor solution and a non-degradable PEG hydrogel precursor solution, e.g., a degradable PEG vinyl sulfone hydrogel precursor solution and a non-degradable PEG vinylAtty. Docket No. UM-42565.601sulfone hydrogel precursor solution. Some kit embodiments further comprise a buffer (e.g., HEPES buffer); a photo initiator; and / or a cross-linker. In some embodiments, the kit comprises: (a) degradable hydrogel precursor solution; (b) a non-degradable hydrogel precursor solution; and (c) a thermosensitive gelatin microgel. 5. Examples It will be readily apparent to those skilled in the art that other suitable modifications and adaptations of the methods of the present disclosure described herein are readily applicable and appreciable, and may be made using suitable equivalents without departing from the scope of the present disclosure or the aspects and embodiments disclosed herein. Having now described the present disclosure in detail, the same will be more clearly understood by reference to the following examples, which are merely intended only to illustrate some aspects and embodiments of the disclosure, and should not be viewed as limiting to the scope of the disclosure. The disclosures of all journal references, U.S. patents, and publications referred to herein are hereby incorporated by reference in their entireties. The present disclosure has multiple aspects, illustrated by the following non-limiting examples. Example 1 For the improvement of the overall graft health, a dual layer polythene glycol hydrogel was developed to protect an ovarian tissue allograft while allowing the tissue to expand. The dual layer polythene glycol hydrogel was improved by the addition of thermosensitive gelatin microgels which increase nutrient diffusion through the gel. The gelatin microgels were incorporated into the outer shell of an immunoisolation device during crosslinking and the gelatin microgels melted to create micron-scale pores when the immunoisolation device was implanted into the body. In in vitro studies, it was found that diffusion of small molecules through the PEG hydrogel was increased and mechanical resilience to strain was increased with the addition of gelatin microgels. Current ongoing mouse studies are investigating the status of the PEGG+ hydrogel immunoisolation device when implanted in both short-term and long-term timeframes. Anticancer treatments are toxic to theAtty. Docket No. UM-42565.601ovary, causing premature ovarian insufficiency (POI) in the growing population of cancer survivors. Prepubescent children are impacted by the alteration of endocrine function increasing risk for cardiovascular disease, obesity and breast cancer. Hormone replacement therapy (HRT) attempts to mimic hormone function, but is unable to facilitate dynamic feedback with the HPG axis. Previous work demonstrated the success of an immune isolating polyethylene glycol (PEG) hydrogel to protect an implanted ovarian allograft for hormone restoration (a “PEG hydrogel immunoisolation device”). However, graft health maybe compromised due to the limited diffusion of nutrients and waste through the hydrogel, which in turn may shorten the duration of graft function. Here, diffusion through a dual layer PEG hydrogel was increased with the addition of thermosensitive sacrificial gelatin microgels thereby improving ovarian allograft survival. Porogen Characterization. The diameter of gelatin microgels centered around 30 µm (FIG.2A). The pore size was quantified using AI image analysis with the majority pores in the 30 µm range (FIG. 2B). The number of large pores increased with the percentage of gelatin. Fluorescently tagged PEG (640nm) and gelatin (488 nm) were imaged to visualize microgels and gelatin melting (FIG.3). PEGG+ Hydrogel Rheology and Diffusion. The percent of FITC tagged dextran molecules diffusing through PEGG+ hydrogels with varying porogen concentration revealed an increased diffusion in the 10% gelatin porogen gels. At larger molecular weight dextran (150 kDa), the diffusion percentage spread was closer, implying the micropores had less of an effect on the diffusion at this scale (immune isolating hydrogel should remain impermeable to cells) (FIGS. 4A-4B).The yield point of gels at 20°C and 37°C increased signifying a larger resistance to strain with the inclusion of gelatin microgels and porogens. Storage modulus decreased implying a decrease in elasticity of the system hydrogels while loss modulus, or viscosity, remained consistent (FIGS.5A-5F). Conclusion. Uniform and tunable thermosensitive gelatin microgels were created using microfluidics and incorporated into a nondegradable PEG hydrogel to introduce distributed but isolated pores in the biomaterial. Diffusion through the gel increased in the presence of porogens with a larger impact being observed on the smaller molecules. PEG gelsAtty. Docket No. UM-42565.601before and after gelatin melting were yielded at a higher strain therefore the microstructure of the material remained intact after a larger force is applied. Example 2 Experiments were conducted to test a method for and analysis of the manufacture of thermosensitive gelatin microgels in PEG hydrogels. It was found that incorporation of thermosensitive gelatin microgels in PEG hydrogels resulted in the creation of void spaces in the PEG hydrogels. The void spaces corresponded to the diameter of the thermosensitive gelatin microgels and increased the diffusion of molecules through the PEG hydrogels without compromising the immune isolating barrier. A dual layer PEG hydrogel immunoisolation device (“PEG device”) was previously developed to protect an ovarian tissue allograft while allowing the tissue to expand. The outer shell of the PEG device was a non-degradable photo crosslinked 4-arm PEG hydrogel that formed a barrier to the immune system, but allowed diffusion of nutrients and waste. The inner core of the PEG device was a degradable 8-arm PEG hydrogel, crosslinked with peptides, that degraded as ovarian follicles grew. Exposure to the circulating gonadotropins in ovariectomized hosts stimulated follicle growth and hormone secretion, mimicking the physiological feedback between multiple organs and tissues involved in pubertal development. The nanoporous nature of the PEG device allowed bidirectional exchange of soluble factors, while maintaining isolation of the ovarian tissue allograft from the immune system. The PEG device was tested extensively in mice and then increased in size for adaptation to human allografts. The increased size required for human adaptation, correspondingly, increased the distance required for oxygen and nutrients to reach the grafts. Thus, a larger immunoisolation device was needed. To attenuate the diffusion limitations of a larger immunoisolation device and to improve graft survival and follicle growth, pores were incorporated into the outer shell of the PEG device to facilitate oxygenation and nutrition to the encapsulated tissue (e.g., a dual layer PEGG+ hydrogel immunoisolation device (“PEGG+ device”)). This was done using microfluidics to create thermosensitive gelatin microgels. Gelatin is a collagen derived peptide that undergoes thermoreversible crosslinking at cool temperatures and solubilization at bodyAtty. Docket No. UM-42565.601temperature. Gelatin microgels were incorporated into a PEG hydrogel to produce porogens, thus forming PEGG+ hydrogel. To test the porosity, the PEGG+ hydrogel was heated to body temperature, allowing for the melting and diffusion of gelatin out of the PEGG+ hydrogel, leaving a void space behind. Fabrication of Gelatin Microgels. A droplet forming two inlet junction microfluidic device was used to create uniform gelatin microgels. A silicon wafer negative was designed according to the specifications and created using lithography methods. A PDMS mold of the silicon negative was created and bonded to a microscope slide. Porcine skin gelatin (Sigma-Aldrich) was dissolved in DPBS at a concentration of 2.5% w / v and run through the aqueous inlet of the device. A solution of 1% fluorosurfactant (RAN Technologies) in Novec 7500 oil (3M) was run through the oil inlet. Flow rates were modulated until a stable flow of 30 µm droplets were being pinched off at the junction. The resulting emulsion was transitioned into an aqueous stage and stored in DPBS at 4° C. To test the effects of body temperature on the gelatin microgels, a tagged sample was kept at 37°C for 10 minutes while in DPBS. For long term storage and transportation, the aqueous phase gelatin microgels were slow frozen by gradually decreasing the temperature at a rate of 1° C per minute until reaching –80° C and subsequently thawed by equilibration in a fridge at 4° C. Image analysis was performed to measure the size of the gelatin microgels using Image J (e.g., the current Fiji version (e.g., v2.13.1 and newer))(e.g., an image processing package – a “batteries-included” distribution of ImageJ (e.g., an open source software for processing and analyzing scientific images), bundling many plugins which facilitate scientific image analysis)) (e.g., Johannes Schindelin et al., Fiji: an Open-Source Platform for Biological Image Analysis, 9 Nature Methods 676-682 (2012))). Formation of PEGG+ Hydrogels. A non-degradable PEG hydrogel was created following a previously defined protocol. In short, 4-arm PEG-VS was dissolved in DPBS with 0.4% Irgacure 2959 and 0.1% N-vinyl-2-pyrrolidone (NVP) creating a final concentration of 5% w / v PEG hydrogel. A concentration of gelatin microgel in DPBS was calculated using a hemocytometer. A correct volume of gelatin microgel in DPBS (e.g., volumes sufficient to produce v / v gelatin microgel concentrations of 0%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%,Atty. Docket No. UM-42565.6015%, and 10% v / v in PEG (e.g., 5% w / v PEG)) was added to a tube and centrifuged into a pellet. The resulting supernatant was aspirated leaving behind a gelatin microgel pellet. A sample of 5% w / v PEG hydrogel was added to the gelatin microgel pellet and mixed thoroughly by pipetting up and down. The resulting PEGG+ hydrogel solution was added to a PDMS mold and crosslinked with UV light 30mV / cm2for 45 seconds to provide a PEGG+ hydrogel. The PEGG+ hydrogel was then characterized using image analysis. The PEGG+ hydrogel was labeled with a fluorescent tag functionalized to CF640R maleimide and CF488A succinate ester, respectively. Various timepoints of the PEGG+ hydrogel were imaged using confocal microscopy. Classification of the pores and quantification of the porosity were imaged using a Weka image classifier of Image J. The number of pores and distribution in the Z stacks was documented. Diffusion Testing of PEGG+ Hydrogels. PEGG+ hydrogels were crosslinked in a transwell and given four days to swell in DPBS at 37°C. Then, 150 uL of 2 uM FITC-Dextran was added to the transwell (on top of the PEGG+ hydrogels) and the transwell was placed in a fresh well of DPBS. Every hour the transwell was moved to a new well and 100 µL of the original DBPS solution was taken and the irradiance of the 488 FITC was measured using a plate reader. The concentration of the solution that passed through the gel was interpolated using standard curves with defined concentrations. Mechanical Testing of PEGG+ Hydrogels. PEGG+ hydrogel precursors 2 mm in thickness were crosslinked, to provide a PEGG+ hydrogels. Cold PEGG+ hydrogels were left to swell at 4°C overnight, while warm PEGG+ hydrogels swelled at 37°C for 5-7 days. Then, all of the PEGG+ hydrogels were biopsy punched into 8mm disks and loaded into a parallel plate rheometer (TA Instruments), while maintaining the defined temperature. A 0.1-1000% strain sweep was performed at a frequency of 1 hz. Yield point was determined using the crossing over point of the G’ and G” lines. In Vivo implantation of PEGG+ hydrogel immunoisolation devices. Slow frozen ovarian cortex pieces were thawed in a series of media dilutions to remove DMSO. The ovarian cortex pieces were then biopsy punched into 4 mm disks and encapsulated in a degradable hydrogel layer crosslinked using 8-arm PEG-VS combined with a YKNS peptide crosslinker at a 1:1 ratio. Then, the encapsulated ovarian cortex pieces were placed in a droplet of UV crossAtty. Docket No. UM-42565.601linkable PEGG+ hydrogel and crosslinked under UV for 45 seconds flipping in the middle to allow for even crosslinking. Immune incompetent mice (Strain- NOD.Cg-PrkdcscidIl2rgtm1Wyl / SzJ, Jackson Laboratories) were ovariectomized dorsally and three dual layer encapsulated ovarian cortex pieces were placed subcutaneously. To monitor hormone cyclicity virginal cytology was performed daily and blood was collected every other week. The mice were sacrificed at week 2, 10, and 12 at which time the dual layer encapsulated ovarian cortex pieces were removed and fixed for further analysis. Characterization and Storage of Gelatin Microgels. Using a microfluidic junction device (FIG. 1A) an emulsion of 2.5% gelatin microgels was created in oil. The resulting microgels were maintained at 4°C and transitioned to the aqueous phase. To account for swelling, the diameters of the microgels were measured in aqueous phase (FIG.1C), and the measurements from each microfluidic run were pooled to create a representative size range. A distribution from 25 µm to 35 µm is observed with the majority of the microgels having a diameter around 30 µm. The differences in shape and microgel packing in oil vs aqueous phase can be observed in FIGS.1B and 1C. To allow for preservation and transport the thermosensitive gelatin, microgels were frozen at –80°C. DMSO was utilized as a cryoprotectant and the microgels were cooled at a rate of 1°C per minute to -80°C, then thawed in the fridge at 4°C. The resulting diameters of the gelatin microgels remain clustered at 40 µm independent of the use of DMSO (FIG.7). Porogen incorporation into PEG hydrogels. Fluorophore tagged gelatin microgels were used to create PEGG+ hydrogels for analysis. Gelatin microgels (488 nm tag) were combined with PEG hydrogel (640 nm tag), prior to UV crosslinking, in concentrations of 0%, 1%, 5%, and 10% v / v / in DMSO. The resulting PEGG+ hydrogels were then crosslinked and imaged immediately. Compared to the PEG hydrogel (i.e., the (control) 0% PEGG+ hydrogel), the 1%, 5%, and 10% PEGG+ hydrogel concentrations had an increased amount of void space. Gelatin microgels were visualized throughout the PEGG+ hydrogels distributed throughout the x, y, and z planes. The 10% PEGG+ hydrogel concentration had more incorporated gelatin microgels and more pores than the other PEGG+ hydrogel concentrations (FIG. 3). Pore size of the PEGG+ hydrogels was measured, leveraging the 640 nm tag, using a trainable image classifier on stained images of the PEGG+ hydrogels (FIG. 2B). The 1% and 5% PEGG+Atty. Docket No. UM-42565.601hydrogel concentrations had pores between 20 μm and 40 μm, with outliers existing between 40 μm and 50 μm. The 10% PEGG+ hydrogel concentration had a large percentage of pores below 50 μm, with outliers extending to 175 μm. The PEGG+ hydrogels were then heated to 37°C for 5 or 24 hours to test the effect of heat on the PEGG+ hydrogels (FIG. 3). The mean grey values of the gelatin microgel (alternatively, “PEGG bead”) signal were used to quantify the intensity of the fluorescence in the images. The gelatin microgels in the 1% and 5% PEGG+ hydrogel concentrations demonstrated a decrease in signal strength between 0 and 24 hours. The gelatin microgel signal intensity of the 10% PEGG+ hydrogel concentration remained relatively constant throughout the melting period. Diffusion Quantification. Long-term diffusion analysis was performed on the 0%, 1%, 5%, and 10% PEGG+ hydrogel concentrations that had been hydrated at 37 °C for 4 days. Overall, the diffusion of small molecules reaches 80% in the PEG hydrogel (i.e., the (control) 0% PEGG+ hydrogel), while larger molecules demonstrated a diffusion of 15%. The diffusion of 4 kDa dextran molecules is constant across the 0%, 1%, 5%, and 10% PEGG+ hydrogel concentrations (FIG.8A). The diffusion of the 40 kDa, 150 kDa, and 66 kDA molecules in the 10% PEGG+ hydrogel concentration is significantly larger than the PEGG hydrogel concentration (i.e., the 0% PEGG+ hydrogel)(FIGS. 8B-8D). The diffusion of the 40 kDa molecules for the 1% and 5% PEGG+ hydrogel concentrations was higher than the 0% PEGG+ hydrogel concentration, but the diffusion rate of the 150 kDa molecules for the 5% PEGG+ hydrogel concentration was not significantly different. Mechanical Characterization using Rheology. A strain sweep test was performed by incrementally increasing the oscillatory strain on a PEGG+ hydrogel using parallel plate rheometer. Yield point is defined as the strain percentage when storage modulus and loss modulus intersect throughout the strain sweep. In response to increasing strain, the yield point of the PEGG+ hydrogels increased with the percentage of gelatin added to the PEG hydrogel for both the warm and cold conditions (FIG.9D and FIG.9G). Storage modulus decreased with the addition of gelatin microgels into the PEG hydrogel (FIG.9E). The warm PEGG+ hydrogel exhibited the same trends as the cold PEGG+ hydrogel (FIG.9H), with a decrease in the storage and loss modulus with an increase in the gelatin porogen concentration. However, the lossAtty. Docket No. UM-42565.601modulus for the warm PEGG+ hydrogels remained constant throughout the various conditions (FIG.9F and 9I). After 20 weeks all implants were recovered and fixed for further analysis. Implants were surrounded by fibrous tissue (FIG. 10E and FIG. 10F) and were integrated into the skin or muscle layer surface (FIG. 10C). The fibrous capsules contained visible vasculature while the implanted tissue grafts remained white indicating removal from blood sources. Further investigation of hormonal changes as well as tissue health is investigated using hormone analysis and staining methods.

Claims

Atty. Docket No. UM-42565.601CLAIMS What is claimed is:

1. An immunoisolation device comprising: (a) a degradable inner core comprising a biological material; and (b) a non-degradable outer shell encapsulating the degradable inner core and comprising a thermosensitive gelatin microgel.

2. The immunoisolation device of claim 1, wherein the concentration of the thermosensitive gelatin microgels comprises about 1% v / v gelatin microgels, 1.5% v / v gelatin microgels, 2% v / v gelatin microgels, 2.5% v / v gelatin microgels, 3% v / v gelatin microgels, 3.5% v / v gelatin microgels, 4% v / v gelatin microgels, 4.5% v / v gelatin microgels, 5% v / v gelatin microgels, or 5.5% v / v gelatin microgels.

3. The immunoisolation device of claim 1, wherein the thermosensitive gelatin microgel is gelatin.

4. The immunoisolation device of claim 1, wherein the degradable inner core and / or the non-degradable outer shell comprises a polyethylene glycol hydrogel.

5. The immunoisolation device of claim 1, wherein: (a) the degradable inner core is configured to allow a cell to grow; and (b) the non-degradable outer shell is configured to allow exchange of metabolites with the environment outside the immunoisolation device and to protect the cell from immune reaction by immune system components outside the immunoisolation device; and (c) the thermosensitive gelatin microgel melts when implanted into the body.Atty. Docket No. UM-42565.6016. The immunoisolation device of claim 1, wherein the biological material comprises at least one of ovarian follicles, germ cells, and / or somatic cells.

7. The immunoisolation device of claim 1, wherein the biological material is a differentiated stem cell or is genetically engineered.

8. The immunoisolation device of claim 1, wherein the degradable inner core comprises a polyethylene glycol.

9. The immunoisolation device of claim 1, wherein the thermosensitive gelatin microgel melts when implanted into the body to provide an immunoisolation device comprising pores in the non-degradable outer shell.

10. The immunoisolation device of claim 9, wherein the non-degradable outer shell comprises about 50 to 250 pores per square nanometer.

11. The immunoisolation device of claim 9, wherein the pores are about 25 µm to 35 µm in diameter.

12. The immunoisolation device of claim 1, wherein the degradable inner core comprises a polyethylene glycol crosslinked with a degradable peptide.

13. A method of preparing an immunoisolation device, the method comprising: (a) providing a biological material; (b) providing a degradable inner core comprising the biological material;Atty. Docket No. UM-42565.601(c) incorporating a thermosensitive gelatin microgel into a non-degradable outer shell; and (d) encapsulating the degradable inner core within the non-degradable outer shell.

14. The method of claim 13, wherein providing the degradable inner core comprises: (a) mixing a hydrogel solution with a protease degradable linker peptide to provide a degradable hydrogel precursor solution; (b) cross-linking the degradable hydrogel precursor solution to provide an inner core comprising a degradable hydrogel; and (c) implanting the biological material in the inner core.

15. The method of claim 13, wherein the degradable inner core and / or the non-degradable outer shell comprises a polyethylene glycol hydrogel.

16. The method of claim 13, wherein incorporating the thermosensitive gelatin microgel into the non-degradable outer shell comprises mixing a PEG hydrogel and a microgel emulsion.

17. The method of claim 13, wherein incorporating the thermosensitive gelatin microgel into the non-degradable outer shell comprises: (a) dissolving a thermosensitive gelatin in a first buffer to provide a thermosensitive gelatin solution; (b) running the thermosensitive gelatin solution through a droplet forming device comprising an aqueous inlet and an oil inlet that meet at a junction;Atty. Docket No. UM-42565.601(c) modulating the flow rate until a stable flow of droplets is produced and the droplets are pinched off at the junction to provide an emulsion; (d) transitioning the emulsion to an aqueous stage and storing in a second buffer; (e) adding a volume of the emulsion to a tube and centrifuging to provide a pellet comprising uniform gelatin microgels; (f) aspirating a supernatant to provide the uniform gelatin microgels; (g) adding a polyethylene glycol hydrogel to the uniform gelatin microgels and mixing thoroughly to provide a polyethylene glycol hydrogel solution.

18. The method of claim 17, wherein running the thermosensitive gelatin solution through a droplet forming device comprises running the thermosensitive gelatin solution through the aqueous inlet of the droplet forming device and running a fluorosurfactant solution in oil through the oil inlet of the droplet forming device.

19. The method of claim 17, wherein a polyethylene glycol hydrogel solution comprises a gelatin microgel concentration of about 1.0% v / v in PEG, 1.0% v / v in PEG, 1.5% v / v in PEG, 2.0% v / v in PEG, 2.5% v / v in PEG, 3.0% v / v in PEG, 3.5% v / v in PEG, 4.0% v / v in PEG, 4.5% v / v in PEG, 5.0% v / v in PEG, 5.5% v / v in PEG, 6.0% v / v in PEG, 6.5% v / v in PEG, 7.0% v / v in PEG, 7.5% v / v in PEG, 8.0% v / v in PEG, 8.5% v / v in PEG, 9.0% v / v in PEG, 9.5% v / v in PEG, or 10.0% v / v in PEG.

20. The method of claim 18, wherein the fluorosurfactant solution has a concentration of about 1% w / v.Atty. Docket No. UM-42565.60121. The method of claim 17, wherein the stable flow of droplets produces droplets about 25 µm to 35 µm in diameter.

22. The method of claim 13, wherein encapsulating the degradable inner core within the non-degradable outer shell comprises (a) placing the inner core in a bead of a polyethylene glycol hydrogel solution and (b) cross-linking the polyethylene glycol hydrogel solution to form the non-degradable outer shell.

23. The method of claim 13 wherein the inner core is configured to expand and contract.

24. The method of claim 13, wherein the inner core is configured to allow the biological material to grow.

25. The method of claim 13, further comprising suspending the biological material in a culture or maintenance medium prior to encapsulation or preserving the biological material in an environment prior to encapsulation.

26. A method of treating a subject who is in need of a bioactive substance, the method comprising: (a) providing an immunoisolation device comprising: (i) an inner core comprising a biological material; and (ii) a non-degradable outer shell encapsulating the inner core and comprising a thermosensitive gelatin microgel; andAtty. Docket No. UM-42565.601(b) implanting the immunoisolation device into the subject, wherein the thermosensitive gelatin microgel melts when implanted into the body.

27. The method of claim 26, wherein the thermosensitive gelatin microgel melts when implanted into the body to provide an immunoisolation device comprising pores in the non- degradable outer shell.

28. The method of claim 27, wherein the non-degradable outer shell comprises about 50 to 250 pores per square nanometer.

29. The method of claim 27, wherein the pores are about 25 µm to 35 µm in diameter.

30. The method of claim 26, wherein the subject suffers from an endocrine deficiency.

31. The method of claim 26, wherein the biological material produces a bioactive substance for which the subject is deficient.

32. The method of claim 26, wherein the subject is a female who had cancer as a child, a female who has had a cytotoxic treatment, and / or a female who is in need of hormone therapy for menopause.

33. A kit comprising: (a) degradable hydrogel precursor solution; (b) a non-degradable hydrogel precursor solution; and (c) a thermosensitive gelatin microgel.

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