Cell housing device

Abstract

To provide a cell housing device.SOLUTION: The present disclosure provides cell housing devices and methods of manufacturing devices having arrays of channels that increase a surface area to volume ratio. In a certain aspect, described herein, a cell housing device, comprises: a first membrane having a first surface comprising a plurality of channels, and a plurality of second surfaces opposing the first surface; and a second membrane opposite and attached to the plurality of the second surfaces of the first membrane, the first membrane and the second membrane forming an enclosed compartment having a surface area to the volume ratio of at least about 40 cm-1, and the enclosed compartment providing a volume for housing a cell within the device.SELECTED DRAWING: None

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 62 / 565,962, filed September 29, 2017, and U.S. Provisional Application No. 62 / 671,297, filed May 14, 2018, which are hereby incorporated by reference. [Background technology]

[0002] Therapeutic devices that deliver biological products can be used to treat metabolic disorders such as diabetes. Therapeutic devices may be implantable for long-term delivery of biological products such as insulin. These devices may include a cell-containing device and a matrix contained within the cell-containing device. The matrix may contain cells that produce the biological product. As the dimensions of the matrix increase, the availability of oxygen and other nutrients may be further reduced away from the edge surface of the matrix, resulting in regions of low or zero oxygen and nutrient concentrations within the matrix. These regions of low or zero oxygen and nutrient concentrations may not be able to support cell viability and biological product synthesis within the matrix. Spatial limitations in transporting oxygen, nutrients, and other agents may limit the size of the device to the dimensions within which oxygen, nutrients, and other agents can reach the cells. Therefore, it may be useful to improve mass transport to the interior regions of such devices and to the interior regions of matrices contained within the cell-containing device. Summary of the Invention [Means for solving the problem]

[0003] FIELD OF THE DISCLOSURE The present disclosure relates generally to medical devices and methods. In various aspects, the present disclosure provides medical devices, including cell-containing devices, related devices, and methods of making and using such devices.

[0004] In certain aspects, described herein is a cell containment device, comprising: a first membrane having a first surface comprising a plurality of channels and a plurality of second surfaces opposing the first surface; and a second membrane opposing and attached to the plurality of second surfaces of the first membrane, wherein the first membrane and the second membrane have a surface area to volume ratio of at least about 40 cm. -1 The enclosed compartment is a cell containment device that provides a volume for containing cells within the device.

[0005] In some embodiments, the compartment comprises a single, contiguous, open space. In some embodiments, the volume is about 8 uL to about 1,000 uL. In some embodiments, the device has at least one of a length and a width of about 0.25 cm to about 3 cm. In some embodiments, the device has a thickness of at least about 300 μm. In some embodiments, the channels are generally perpendicular to the first membrane. In some embodiments, the channels are arranged in a linear array. In some embodiments, the channels are arranged in a polar array. In some embodiments, the channels have an average diameter of about 400 μm to about 3,000 μm. In some embodiments, the diameter is measured at the narrowest point within the channel. In some embodiments, the center of each channel is separated from the center of another channel by a distance of about 75 μm to about 500 μm. In some embodiments, the channels have a height-to-diameter ratio of at least about 0.2. In some embodiments, the device has about 50 channels per cm of area along its cross section. 2In some embodiments, at least one of the first membrane and the second membrane comprises a plurality of nodes interconnected by a plurality of fibrils. In some embodiments, at least one of the first membrane and the second membrane comprises PVDF, PTFE, ePTFE, PCL, PE / PES, PP, PS, PMMA, PLGA, PLLA, or any combination thereof. In some embodiments, the device further comprises an opening through the first membrane and the second membrane within the channel. In some embodiments, the opening is concentric with the channel by at most 25% of the diameter of the channel. In some embodiments, the device further comprises a frame configured to receive the device. In some embodiments, the frame is configured to receive a plurality of cell-containing devices. In some embodiments, the frame comprises a flexible mechanism configured to prevent buckling of the cell-containing devices. In some embodiments, the device further comprises a cell population. In some embodiments, the cell population is an insulin-secreting population. In some embodiments, the cell population is stem cell-derived cells capable of glucose-stimulated insulin secretion (GSIS). In some embodiments, the device further comprises a coating comprising a hydrophilic polymer. In some embodiments, the device has an insulin diffusion coefficient of about 2x10^-6 cm 2 / s~approx.1x10^-5cm 2 / s. In some embodiments, the device has a maximum insulin diffusion distance of less than about 150 μm. In some embodiments, the first membrane and the second membrane are fused with a fusion peel force of at least about 0.4 N. In some embodiments, at least one of the first membrane and the second membrane is semipermeable. In some embodiments, the semipermeability of the first membrane, the second membrane, or both is configured to protect cells from immune attack. In some embodiments, the semipermeability of the first membrane, the second membrane, or both is configured to protect cells from immune attack in the absence of immunosuppressive therapy. In some embodiments, at least one of the first membrane and the second membrane is configured to allow vascularization of cells within the device. In some embodiments, at least one of the first membrane and the second membrane is configured to allow vascularization of cells within the device in the absence of immunosuppressive therapy.

[0006] Another aspect provided herein is a cell containment device comprising: a first membrane having a first surface comprising a plurality of channels and a plurality of second surfaces opposing the first surface; and a second membrane opposing and attached to the plurality of second surfaces of the first membrane, wherein the first and second membranes form an enclosed compartment, the enclosed compartment providing a volume for containing one million to one billion insulin-producing cells within the device, and the membrane retains the insulin-producing cells within the device while allowing diffusion of insulin from the device.

[0007] Another aspect provided herein is a composition comprising insulin-producing cells and a device containing the insulin-producing cells, wherein the device, when implanted into an individual, releases insulin while retaining the insulin-producing cells within the device and facilitating tissue vascularization within and around the device. In some embodiments, the individual is not administered immunosuppressants during implantation or vascularization of the device. In some embodiments, the device comprises between 1 million and 1 billion insulin-producing cells. In some embodiments, the device is at least about 300 μm thick. In some embodiments, the device comprises a membrane comprising a plurality of nodes interconnected by a plurality of fibrils.

[0008] In another aspect, described herein is a method of manufacturing a cell containment device, the method including providing a first membrane having a first surface and an opposing second surface; forming a plurality of channels in the first surface of the first membrane; and fusing a second membrane to the second surface of the first membrane to form a compartment for containing cells between the second surface of the first membrane and the second membrane.

[0009] In some embodiments, forming the plurality of channels in the first membrane includes heating the first membrane at a predetermined pressure and a predetermined temperature for a predetermined time, and molding the plurality of channels using a mold. In some embodiments, fusing the second membrane to the first membrane occurs in a mold. In some embodiments, the mold includes a positive mold. In some embodiments, the mold includes a negative mold. In some embodiments, the predetermined temperature is between about 100°C and about 600°C. In some embodiments, the predetermined pressure is between about 2 pounds per square inch (psi) and about 140 psi. In some embodiments, the predetermined time is between about 3 minutes and about 30 minutes. In some embodiments, the predetermined pressure is about 3.5 psi and the predetermined temperature is about 370°C. In some embodiments, forming a plurality of channels in the first membrane and fusing the second membrane to the first membrane includes placing the first membrane and the second membrane in a frame, where the first membrane and the second membrane are substantially parallel, substantially aligned, and separated by a gap distance; and striking one or more dots on the first membrane with a fusing tool, where the fusing tool is heated to a set fusing temperature and the fusing tool contacts the membrane for a set fusing time between each dot. In some embodiments, striking the first membrane penetrates the first membrane, the second membrane, or both, fusing a portion of the first membrane to the second membrane. In some embodiments, the frame surrounds at least a portion of the outer edges of the first membrane and the second membrane. In some embodiments, the gap distance is about 300 μm to about 1,200 μm. In some embodiments, the fusing tool has a dot contact area of ​​at least about 0.07 mm. 2In some embodiments, forming one or more dots on the first membrane with a fusing tool includes forming each of the one or more dots up to about 16 times. In some embodiments, forming one or more dots on the first membrane with a fusing tool includes forming each of the one or more dots 1 to 6 times. In some embodiments, the set fusing temperature is about 250°C to about 600°C. In some embodiments, the set fusing time is less than about 1 second. In some embodiments, at least one of the first membrane and the second membrane is substantially flat. In some embodiments, the method further includes embossing the first membrane before forming the plurality of channels in the first membrane. In some embodiments, the method further includes laser ablating portions of the first membrane and the second membrane within the plurality of channels. In some embodiments, the laser ablation removes the fused portions of the first membrane and the second membrane to form openings. In some embodiments, the openings are concentric with the channels by up to 25% of the diameter of the channels. In some embodiments, at least one of the first membrane and the second membrane comprises PVDF, PTFE, ePTFE, PCL, PE / PES, PP, PS, PMMA, PLGA, PLLA, or any combination thereof. In some embodiments, the method further comprises coating the device with a hydrophilic polymer. In some embodiments, the first membrane is sintered. In some embodiments, the second membrane is not sintered. In some embodiments, the second membrane and the first membrane are fused with a fusion peel force of at least about 0.2 N.

[0010] Another aspect provided herein is a method, comprising contacting tissue of a diabetic or prediabetic subject with a device comprising an insulin-secreting cell population, the device comprising: a first membrane having a first surface comprising a plurality of channels and a plurality of second surfaces opposing the first surface; and a second membrane opposing and attached to the plurality of second surfaces of the first membrane, the first membrane and the second membrane having a surface area to volume ratio of at least about 40 cm. -1 and releasing insulin from the insulin-secreting cell population in response to an elevated blood glucose level in the diabetic subject, the elevated glucose level being greater than the blood glucose level in a non-diabetic subject.

[0011] In some embodiments, the insulin-secreting cell population releases insulin in an amount sufficient to lower blood glucose levels in a diabetic or pre-diabetic subject. In some embodiments, releasing insulin ceases once blood glucose levels in the diabetic subject have decreased to normal levels. In some embodiments, releasing insulin resumes when the insulin-secreting cell population is again exposed to elevated blood glucose levels in the diabetic subject. In some embodiments, the insulin-secreting cell population is a stem cell-derived cell population. In some embodiments, the insulin-secreting cell population is capable of glucose-stimulated insulin secretion (GSIS). In some embodiments, at least one of the first membrane and the second membrane is semipermeable. In some embodiments, the semipermeability of the first membrane, the second membrane, or both is configured to protect the cells from immune attack. In some embodiments, the semipermeability of the first membrane, the second membrane, or both is configured to protect the cells from immune attack in the absence of immunosuppressive therapy. In some embodiments, at least one of the first membrane and the second membrane is configured to allow vascularization of the cells within the device. In some embodiments, at least one of the first membrane and the second membrane is configured to allow vascularization of cells within the device in the absence of immunosuppressive therapy.

[0012] In certain embodiments, described herein is a cell containment device comprising: a first surface defining an exterior of the device and having a surface area; a second surface opposite the first surface, the second surface defining an interior of the device; and a compartment enclosed within the second surface, the compartment providing a volume for containing cells within the device, the surface area to volume ratio being 50 cm. -1In some embodiments, the cell containment device has a diameter of 400 μm or greater. In some embodiments, the device includes a plurality of channels running through a cross section of the device. In some embodiments, each channel of the plurality of channels has a diameter of 400 μm or greater. In some embodiments, the diameter is measured at the narrowest point within the channel. In some embodiments, each channel of the plurality of channels is separated from each other by a distance not exceeding 450 μm. In some embodiments, each channel of the plurality of channels has a height-to-diameter ratio of 0.2 or greater. In some embodiments, the number of channels per area measured along the cross section of the device is 50 / cm. 2 In some embodiments, the number of channels per area measured along the cross section of the device is greater than 100 / cm 2 In some embodiments, the surface area to volume ratio is greater than 80 cm -1 In some embodiments, the surface area to volume ratio is greater than 100 cm -1 In some embodiments, the surface area to volume ratio is greater than 120 cm -1 In some embodiments, the device comprises a single, continuous, open space having a volume. In some embodiments, the first surface or the second surface comprises a plurality of nodes interconnected by a plurality of fibrils. In some embodiments, the device has a thickness measured along a cross-section of the device of greater than 300 μm. In some embodiments, the first surface or the second surface comprises PVDF, PTFE, ePTFE, PCL, PE / PES, PP, PS, PMMA, PLGA, or PLLA. In some embodiments, the device further comprises a frame, the frame configured to receive the device. In some embodiments, the frame is configured to receive a plurality of cell-containment devices. In some embodiments, the frame comprises a flexible mechanism that prevents buckling of the cell-containment devices. In some embodiments, the device further comprises a cell population. In some embodiments, the cell population is an insulin-secreting population. In some embodiments, the cell population is stem cell-derived cells capable of glucose-stimulated insulin secretion (GSIS).

[0013] In some embodiments, the device further comprises a coating of a hydrophilic polymer. In some embodiments, the volume for containing cells is inversely proportional to at least one of the diameter of the plurality of channels and the number of channels per area of ​​the device. In some embodiments, the surface area-to-volume ratio of the device is directly proportional to at least one of the diameter of the plurality of channels and the number of channels per area of ​​the device. In some embodiments, the surface area-to-volume ratio of the device allows for greater mass transport into and / or out of the device. In other embodiments, described herein are cell-containment devices comprising a base, an upper surface opposite the base, a height extending from the base to the upper surface along a cross-section of the device, the height being greater than 300 μm, a compartment for containing cells, the compartment being enclosed between the base and the upper surface, and a plurality of channels extending along the cross-section of the device, wherein the maximum oxygen diffusion distance of the device is less than 150 μm. In some embodiments, the height of the device is greater than 600 μm. In some embodiments, the base is substantially flat. In some embodiments, each channel of the plurality of channels has a diameter of 400 μm or greater. In some embodiments, each channel of the plurality of channels is separated from the others by a distance not exceeding 450 μm. In some embodiments, each channel of the plurality of channels has a diameter of 400 μm or greater. In some embodiments, the diameter is measured at the narrowest point within the channel. In some embodiments, each channel of the plurality is separated from the others by a distance not exceeding 450 μm. In some embodiments, each channel of the plurality has a height-to-diameter ratio of 0.2 or greater. In some embodiments, the number of channels per area measured along the cross-section of the device is 50 / cm. 2 In some embodiments, the number of channels per area measured along the cross section of the device is greater than 100 / cm 2In some embodiments, the device includes a single continuous compartment for containing cells. In some embodiments, the first surface or the second surface includes a plurality of nodes interconnected by a plurality of fibrils. In some embodiments, the first surface or the second surface includes PVDF, PTFE, ePTFE, PCL, PE / PES, PP, PS, PMMA, PLGA, or PLLA. In some embodiments, the device further includes a frame configured to receive the device. In some embodiments, the frame is configured to receive a plurality of cell-containment devices. In some embodiments, the frame includes a flexible mechanism that prevents buckling of the cell-containment devices. In some embodiments, the device further includes a cell population. In some embodiments, the cell population is an insulin-secreting population. In some embodiments, the cell population is stem cell-derived cells capable of glucose-stimulated insulin secretion (GSIS). In some embodiments, the device further includes a coating with a hydrophilic polymer. In some embodiments, the volume for containing cells is inversely proportional to at least one of the diameter of the plurality of channels and the number of channels per area of ​​the device. In some embodiments, the surface area to volume ratio of the device is directly proportional to at least one of the diameter of the plurality of channels and the number of channels per area of ​​the device. In some embodiments, the surface area to volume ratio of the device is directly proportional to at least one of the diameter of the plurality of channels and the number of channels per area of ​​the device. In some embodiments, increasing the surface area to volume ratio of the device allows for greater mass transport into and / or out of the device.

[0014] In other aspects, described herein are methods of manufacturing a cell containment device, the methods including providing a first membrane; adjusting a temperature and / or pressure surrounding the first membrane to a predetermined value; deforming the first membrane; and fusing a second membrane to the first membrane, wherein a compartment between the first membrane and the second membrane defines a compartment for containing cells. In some embodiments, the predetermined value is less than 170 degrees Celsius (C). In some embodiments, the predetermined value is less than 140 pounds per square inch (psi). In some embodiments, the predetermined value is less than 370 degrees Celsius. In some embodiments, the predetermined value is less than 5 psi. In some embodiments, deforming the first membrane includes depressing a portion of the first membrane with a tool. In some embodiments, the tool includes a substantially flat surface configured to be parallel to the first membrane and a plurality of protrusions on the surface configured to depress a portion of the first membrane. In some embodiments, each of the plurality of protrusions comprises a cylinder. In some embodiments, the tool comprises a tip, the tip having a contact area at a free end. In some embodiments, the contact area is 0.07 mm 2That is all. In some embodiments, the fusing is performed using a tip, which presses the first and second membranes together and keeps them in contact with each other for a predetermined period of time. In some embodiments, the deformation and fusing are performed in one step using a tip, which contacts the first membrane, moves vertically away from the first membrane toward the second membrane, and presses the first and second membranes together and keeps them in contact with each other for a predetermined period of time. In some embodiments, the tip is adjusted to a predetermined temperature. In some embodiments, the tip presses with a predetermined pressure. In some embodiments, the predetermined period of time is 1 second or longer. In some embodiments, the cylinder has a diameter of 300 μm or greater. In some embodiments, the cylinder has a height of 300 μm or greater. In some embodiments, deforming the first membrane is performed without causing cracks in the membrane. In some embodiments, deforming the first membrane includes forming a plurality of features on the membrane. In some embodiments, each of the plurality of features has a diameter of 300 μm or greater. In some embodiments, each of the plurality of features has a depth of 300 μm or more. In some embodiments, the method further includes adjusting the temperature and / or pressure surrounding the first membrane to control the characteristics of the features. In some embodiments, increasing the temperature and / or pressure surrounding the first membrane increases the depth of the features. In some embodiments, fusing the second membrane to the first membrane includes fusing the second membrane and the first membrane into a single continuous layer. In some embodiments, fusing the second membrane to the first membrane begins at a temperature and / or pressure having a second predetermined value. In some embodiments, the second predetermined value is less than 230° Celsius (C). In some embodiments, the second membrane is substantially flat. In some embodiments, after deformation, the first membrane is embossed. In some embodiments, after fusing, the device has a substantially flat surface and an embossing surface opposite the substantially flat surface.In some embodiments, the method further includes removing fused portions of the first and second membranes by laser ablation to form a transverse channel through the device. In some embodiments, the method further includes attaching the device to a frame. In some embodiments, the method further includes implanting the device on the frame into a subject. In some embodiments, the method further includes encapsulating cells within the compartments. In some embodiments, the method further includes implanting the device into a subject. In some embodiments, the first membrane or the second membrane comprises PVDF, PTFE, ePTFE, PCL, PE / PES, PP, PS, PMMA, PLGA, or PLLA. In some embodiments, the method further includes coating the device with a hydrophilic polymer. In some embodiments, the first membrane is sintered. In some embodiments, the second membrane is not sintered.

[0015] In other aspects, described herein are cell containment devices including a base, an upper surface opposite the base, a height extending from the base to the upper surface along a cross-section of the device, the height being 300 μm or less, and a compartment for containing cells, the compartment being enclosed between the base and the upper surface. In some embodiments, the height is less than 250 μm. In some embodiments, the base includes a sintered membrane. In some embodiments, the upper surface includes a sintered membrane. In some embodiments, the base includes a coated membrane, the coating increasing the hydrophilicity of the membrane. In some embodiments, the device includes at least one fused dot, the dot including fusing a portion of the base to a portion of the upper surface corresponding to the portion of the base, the dot configured to limit changes in height. In some embodiments, the dot is about 0.5 mm to about 3 mm in diameter. In some embodiments, the dot is at least about 0.5 mm in diameter. In some embodiments, the dot is at most about 3 mm in diameter.In some embodiments, the dots have a diameter of about 0.5 mm to about 0.75 mm, about 0.5 mm to about 1 mm, about 0.5 mm to about 1.25 mm, about 0.5 mm to about 1.5 mm, about 0.5 mm to about 1.75 mm, about 0.5 mm to about 2 mm, about 0.5 mm to about 2.25 mm, about 0.5 mm to about 2.5 mm, about 0.5 mm to about 2.75 mm, about 0.5 mm to about 3 mm, about 0.75 mm to about 1 mm, about 0.75 mm to about 1.25 mm, about 0.75 mm to about 1. .5mm, about 0.75mm to about 1.75mm, about 0.75mm to about 2mm, about 0.75mm to about 2.25mm, about 0.75mm to about 2.5mm, about 0.75mm to about 2.75mm, about 0.75mm to about 3mm, about 1mm ~1.25mm, 1mm~1.5mm, 1mm~1.75mm, 1mm~2mm, 1mm~2.25mm, 1mm~2.5mm, 1mm~2.75mm, 1mm~3mm, 1.25m m ~ about 1.5mm, about 1.25mm - about 1.75mm, about 1.25mm - about 2mm, about 1.25mm - about 2.25mm, about 1.25mm - about 2.5mm, about 1.25mm - about 2.75mm, about 1.25mm - about 3mm, Approximately 1.5mm to approximately 1.75mm, approximately 1.5mm to approximately 2mm, approximately 1.5mm to approximately 2.25mm, approximately 1.5mm to approximately 2.5mm, approximately 1.5mm to approximately 2.75mm, approximately 1.5mm to approximately 3mm, approximately 1.75mm to approximately 2mm, approximately 1 In some embodiments, the dots are about 0.75 mm to about 2.25 mm, about 1.75 mm to about 2.5 mm, about 1.75 mm to about 2.75 mm, about 1.75 mm to about 3 mm, about 2 mm to about 2.25 mm, about 2 mm to about 2.5 mm, about 2 mm to about 2.75 mm, about 2 mm to about 3 mm, about 2.25 mm to about 2.5 mm, about 2.25 mm to about 2.75 mm, about 2.25 mm to about 3 mm, about 2.5 mm to about 2.75 mm, about 2.5 mm to about 3 mm, or about 2.75 mm to about 3 mm in diameter. In some embodiments, the dots are about 0.5 mm, about 0.75 mm, about 1 mm, about 1.25 mm, about 1.5 mm, about 1.75 mm, about 2 mm, about 2.25 mm, about 2.5 mm, about 2.75 mm, or about 3 mm in diameter. In some embodiments, the dots are spaced at least 3 mm from another fused dot, hi some embodiments, the dots are formed using adhesive disposed between a portion of the base and a portion of the top surface.In some embodiments, the volume of the compartment is inversely proportional to at least one of the diameter of the dots and the number of dots per area of ​​the device. In some embodiments, the ratio of the surface area of ​​the device to the volume of the device is directly proportional to at least one of the diameter of the dots and the number of dots per area of ​​the device. In some embodiments, increasing the surface area to volume ratio of the device allows for greater mass transport into and / or out of the device.

[0016] In another aspect, described herein is a method comprising: a) contacting tissue of a diabetic subject with a device comprising an insulin-secreting cell population, the device comprising: a first surface defining an exterior of the device and having a surface area; a second surface opposite the first surface and defining an interior of the device; and a compartment enclosed within the second surface, the compartment providing a volume for containing the cells within the device, the compartment having a surface area to volume ratio of 50 cm. -1 and b) releasing insulin from the insulin-secreting cell population in response to elevated blood glucose levels in the diabetic subject, wherein the elevated glucose level is higher than the blood glucose level in a non-diabetic subject. In some embodiments, the insulin-secreting cell population releases insulin in an amount sufficient to lower the blood glucose level in the diabetic subject. In some embodiments, releasing insulin ceases once the blood glucose level in the diabetic subject has lowered to a normal level. In some embodiments, releasing insulin resumes when the insulin-secreting cell population is again exposed to elevated blood glucose levels in the diabetic subject. In some embodiments, the insulin-secreting cell population is a stem cell-derived cell population. In some embodiments, the insulin-secreting cell population is capable of glucose-stimulated insulin secretion (GSIS).

[0017] In other aspects, described herein are methods including: a) contacting tissue of a diabetic subject with a device comprising an insulin-secreting cell population, the device comprising: a base; an upper surface opposite the base; a height extending from the base to the upper surface along a cross-section of the device that is greater than 300 μm; a compartment for containing cells, the compartment enclosed between the base and the upper surface; and a plurality of channels extending along the cross-section of the device, wherein the maximum oxygen diffusion distance of the device is less than 150 μm; and b) releasing insulin from the insulin-secreting cell population in response to an increase in blood glucose levels in the diabetic subject, the increased glucose levels being higher than blood glucose levels in a non-diabetic subject. In some aspects, the insulin-secreting cell population releases insulin in an amount sufficient to lower blood glucose levels in the diabetic subject. In some aspects, releasing insulin ceases when blood glucose levels in the diabetic subject decrease to normal levels. In some embodiments, insulin release resumes when the insulin-secreting cell population is again exposed to elevated blood glucose levels in the diabetic subject. In some embodiments, the insulin-secreting cell population is a stem cell-derived cell population. In some embodiments, the insulin-secreting cell population is capable of glucose-stimulated insulin secretion (GSIS).

[0018] In other aspects, described herein are methods comprising: a) contacting tissue of a diabetic subject with a device comprising an insulin-secreting cell population, the device comprising a base, an upper surface opposite the base, a height extending from the base to the upper surface along a cross-section of the device that is no greater than 300 μm, and a compartment for containing cells, the compartment being enclosed between the base and the upper surface; and b) releasing insulin from the insulin-secreting cell population in response to elevated blood glucose levels in the diabetic subject, the elevated glucose levels being higher than blood glucose levels in a non-diabetic subject. In some aspects, the insulin-secreting cell population releases insulin in an amount sufficient to lower blood glucose levels in the diabetic subject. In some aspects, releasing insulin ceases once blood glucose levels in the diabetic subject have decreased to normal levels. In some aspects, releasing insulin resumes when the insulin-secreting cell population is again exposed to elevated blood glucose levels in the diabetic subject. In some embodiments, the insulin-secreting cell population is a stem cell-derived cell population. In some embodiments, the insulin-secreting cell population is capable of glucose-stimulated insulin secretion (GSIS).

[0019] Incorporation by Reference All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.

[0020] The novel features of the present disclosure are set forth with particularity in the appended claims. The features and advantages of the present disclosure will be better understood by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the present disclosure are utilized, and the accompanying drawings of which: [Brief explanation of the drawings]

[0021] [Figure 1]1 is a high magnification image of a polyvinylidene fluoride (PVDF) cell containment device, according to some embodiments. [Figure 2] 10A-10C illustrate how the amount of cells loaded into the device varies with dot pitch and the presence of restrictions, according to some embodiments. [Figure 3] FIG. 10 illustrates zones of different oxygen pressures within a two-layer flat sheet and channel array device, according to some embodiments. [Figure 4] 1A-1C illustrate the surface area and angiogenic potential of a device with a planar configuration and a device with a channel array, according to some embodiments. [Figure 5] 10A-10C illustrate increased vascularization with a device with a planar configuration or a channel array device, according to some embodiments. [Figure 6] 1A-1C show computer-aided design (CAD) renderings of various sized hexagonal channel array devices, according to some embodiments. [Figure 7] 1A-1C are CAD renderings of a cell-containing device and scanning electron micrographs of a cross section of a cell-containing device, according to some embodiments. [Figure 8] 10A-10C illustrate how a membrane transforms from a flat configuration to a shaped configuration with channels, according to some embodiments. [Figure 9] 10 is an image of a pattern in which a first membrane is fused with a flat second membrane after a deformation step and the fused first and second membranes, according to some embodiments. [Figure 10] 1A-1C are scanning electron micrographs of a cross section of a cell-containing device and scanning electron micrographs at higher magnification along various portions of the cell-containing device, according to some embodiments. [Figure 11] 1A-1C are scanning electron micrographs at low and high magnification of a cross section of a cell-containing device at the interface of fused first and second membranes, according to some embodiments. [Figure 12]1A-1C are scanning electron micrographs of cross-sections of polyvinylidene fluoride (PVDF) membranes after undergoing deformation steps at various temperatures and pressures, according to some embodiments. [Figure 13] 1A-1C are scanning electron micrographs of cross sections of cell-containing devices after undergoing fusion steps at various temperatures and pressures, according to some embodiments. [Figure 14] 10 is a rendering of a cell containment device with a scalloped perimeter and varying channel dimensions to achieve different SA:V ratios, according to some embodiments. [Figure 15] FIG. 1 shows heat flow measurements of a PVDF membrane before treatment, after treatment and quenching at 173° C. and 100 psi, and after treatment at 160° C. and 100 psi, according to some embodiments. [Figure 16] 10A-10C are scanning electron micrographs of cross sections of cell-containing devices subjected to a deformation step under different pressure and temperature conditions, according to some embodiments. [Figure 17] 10A-10C show measured channel depths in cell-containing devices subjected to deformation steps at different pressure and temperature conditions, according to some embodiments. [Figure 18] 1 is a surface interferometry profile of a cell-containing device, according to some embodiments. [Figure 19] 1A-1C are scanning electron micrographs taken at low and high magnification of an expanded polytetrafluoroethylene (ePTFE) first membrane after a deformation step at various temperatures and pressures, according to some embodiments. [Figure 20] 1 is a scanning electron micrograph of an ePTFE cell-containing device after a deformation step at 360° C. and 6 psi and a fusion step at 370° C. for 5 minutes, according to some embodiments. [Figure 21] 10A-10C are scanning electron micrographs and images of a cell-containing device with fused lumen cut by laser ablation, according to some embodiments. [Figure 22] 1 is a scanning electron micrograph of a cross section of a cell-containing device after fabrication, according to some embodiments. [Figure 23] 10A-10C illustrate the design of a hexagonal channel array device and a macro device attached with a flexible mechanism, according to some embodiments. [Figure 24] 1A-1C illustrate the loading of a cell-containing mixture into a cell containment device, according to some embodiments, in a configuration where the device is mounted on a supporting mechanical frame (left) and in a configuration where an external loading tube and frameless design are used (right). [Figure 25] FIG. 1 shows a hematoxylin and eosin (H&E) stained tissue section of a cell-containing device loaded with a matrix with cells, according to some embodiments. [Figure 26] FIG. 10 shows the vasculature around a cell-containing device 20 days after implantation in a rat, according to some embodiments. [Figure 27] FIG. 10 shows the vasculature around a cell-containing device 90 days after implantation in a rat, according to some embodiments. [Figure 28] FIG. 1 illustrates preperitoneal, intraomental, suprahepatic, and subcutaneous implantation of a cell-containing device into a rat, according to some embodiments. [Figure 29] 10A-10C show H&E stained histological sections of angiogenesis around a cell-containing device and vasculature within the channels after in vivo implantation in a rat, according to some embodiments. [Figure 30] 1A-1C illustrate vascularization around low channel density and high channel density cell-containing devices after implantation in vivo, according to some embodiments. [Figure 31] 1A-1C show the number of blood vessels and blood vessel branches per device observed in low channel density and high channel density cell-containing devices after in vivo implantation, according to some embodiments. [Figure 32] FIG. 1 illustrates the effect of device design on insulin response and surface area to volume ratio, according to some embodiments. [Figure 33] FIG. 1 illustrates the surface area to volume ratio achievable by varying channel density for 500 μm diameter channels and estimated acceptable cluster size, according to some embodiments. [Figure 34] 1 is a schematic diagram of a fusion process by spot welding two membranes with a tip, according to some embodiments. [Figure 35] FIG. 10 shows the breaking load of two flat ePTFE membranes fused at different temperatures for different lengths of time, according to some embodiments. [Figure 36] 1 is a scanning electron micrograph of the edges of a device sealed at 345° C. for 0.5 seconds, according to some embodiments. [Figure 37] FIG. 1 illustrates a typical peel test stress strain curve, according to some embodiments. [Figure 38] FIG. 1 shows an ePTFE cell containment device after a hydrophilic coating treatment in water, according to some embodiments. [Figure 39] FIG. 1 shows a frameless ePTFE cell containment device filled to burst according to some embodiments, and a graph of the fill pressure (psi) at failure for PVDF and ePTFE cell containment device prototypes. [Figure 40] FIG. 1 illustrates three prototype cell containment devices assembled on a frame for human use, according to some embodiments. [Figure 41] 1A-1C illustrate examples of protocols for forming a hydrophilic coating on the surface of a membrane, according to some embodiments. [Figure 42] FIG. 1 shows an H&E stained tissue section of the continuous interior space of an ePTFE and PVDF cell containment device completely filled with cells, according to some embodiments. [Figure 43] 1 is an image of an ePTFE cell containment device filled to capacity with cells, according to some embodiments. [Figure 44] FIG. 1 shows an H&E stained histological section of a PVDF cell containment device with cells 90 days after in vivo implantation into the preperitoneal site of a rat, according to some embodiments. [Figure 45]FIG. 1 shows H&E stained histological sections of a PVDF cell containment device loaded with SC islet cells 90 days after implantation into subcutaneous and preperitoneal sites in a rat, according to some embodiments. [Figure 46] FIG. 1 illustrates an example of a macro device including three ultra-thin devices, according to some embodiments. [Figure 47] 1A-1C are scanning electron micrographs of different ePTFE membranes that can be utilized for ultra-thin devices, according to some embodiments. [Figure 48] FIG. 1 shows the flux of C-peptide in response to a 20 mM glucose stimulus in an implanted high-flux ultrathin device with a permselective membrane and loaded with rat pancreatic islet cells, according to some embodiments. [Figure 49] FIG. 1 shows static C-peptide release in an ultra-thin device loaded with encapsulated islet cells and with a high-flux or permselective membrane according to some embodiments, before (LG or low glucose), during (HG), and after (LG) high glucose stimulation. [Figure 50] FIG. 1 shows dynamic GSIS (glucose stimulated insulin secretion) of an ultra-thin device with an AS1 membrane, according to some embodiments. [Figure 51] 1A-1C are scanning electron micrographs of unsintered and sintered membranes and changes in the membrane microstructure, according to some embodiments, where fusion and coalescence of membrane nodes and fibrils are present. [Figure 52] FIG. 1 shows a comparison of hydrophilic coating processes that resulted in membranes with a target insulin flux near 1×10 mol / m 2 / s, according to some embodiments. [Figure 53] 1A-1C show membranes coated with three different coating processes V1, V2, and V3 stained with H&E dye as an indication of membrane hydrophilicity, according to some embodiments. [Figure 54]1A-1C illustrate the water permeability of membranes, membranes with a V1 coating process, and membranes with a V3 coating process, according to some embodiments. [Figure 55] FIG. 1 illustrates a setup for scaling up a coating process with dry and wet coated membranes, according to some embodiments. [Figure 56] FIG. 10 shows a simulation of the mechanical properties of a 300 μm thick PEEK frame for two cell-containment devices under a force of 150 mN, according to some embodiments. [Figure 57] FIG. 10 shows an example of a PEEK frame holding a cell-containing device with a fused dot at the center of the device, according to some embodiments. [Figure 58] 10 is an image of a single frame module with a single cell containment device with maximally filled, centrally fused dots on the frame, according to some embodiments. [Figure 59] FIG. 10 shows H&E stained tissue sections at days 2, 4, 8, and 10 in a maximally filled cell-containing device stored under standard conditions of 20% oxygen and 37° C. with high cell viability over 10 days of storage, according to some embodiments. [Figure 60] FIG. 1 shows blood glucose levels over 90 days of implantation of an ultra-thin cell-containing device loaded with SC islet cells and with an AS1 membrane in a NODscid gamma (NSG) mouse model, an immunodeficient mouse model, according to some embodiments. [Figure 61A] 1 is an image of an ultra-thin device with a high-flux ePTFE membrane with a hydrophilic coating and loaded with 8 million SC islet cells, according to some embodiments. [Figure 61B] 10 is an H&E stained image of a high density of cells throughout a device, including the nucleus, after 90 days of implantation in an NSG mouse model, according to some embodiments. [Figure 61C]10 is an H&E stained image of a high density of cells throughout a device, including the nucleus, after 90 days of implantation in an NSG mouse model, according to some embodiments. [Figure 62] 10 is a low magnification image of a histological section of a cell-loaded ultrathin device with an AS1 membrane and loaded with SEM-01 cells after 30 days of in vivo implantation in a mouse model, according to some embodiments. [Figure 63] 10 is a high magnification image of a histological section of a cell-loaded ultrathin device with an AS1 membrane and loaded with SEM-01 cells after 30 days of in vivo implantation in a mouse model, according to some embodiments. [Figure 64] FIG. 1 illustrates microaggregates of endocrine cells prior to encapsulation and loading into a cell containment device, according to some embodiments. [Figure 65] 10 is a stained histological image of an ultrathin device loaded with endocrine cell microaggregates after three months of implantation in a mouse, according to some embodiments. [Figure 66] FIG. 1 shows serum C-peptide and total insulin content levels in endocrine cell-implanted mice or endocrine cell-loaded ultra-thin devices, according to some embodiments. [Figure 67] 10 is an H&E stained image of an explant of an ultra-thin device comprising a coated permselective membrane loaded with SC islet cells after 3 months in a nude rat in a preperitoneal site, according to some embodiments. [Figure 68] 10 is an H&E stained image of an ultra-thin device loaded with 16 million SC islet cells after 12 weeks of implantation at a preperitoneal site in a nude mouse model, according to some embodiments. [Figure 69] FIG. 1 shows serum C-peptide levels over a 60 minute period in four different mice implanted with ultra-thin devices loaded with SC islet cells, according to some embodiments. [Figure 70A] A and B are H&E stained images of an empty ultrathin device with an AS1 membrane implanted into an immunocompetent Black 6 mouse model that did not induce a foreign body reaction (FBR), according to some embodiments. [Figure 70B] A and B are H&E stained images of an empty ultrathin device with an AS1 membrane implanted into an immunocompetent Black 6 mouse model that did not induce a foreign body reaction (FBR), according to some embodiments. [Figure 71] 10 is an H&E stained image of an ultrathin device with viable intact rat pancreatic islet cells after 90 days in vivo, according to some embodiments. [Figure 72] 1 shows blood glucose levels before, during, and 90 days after implantation of an ultra-thin device in a diabetic mouse model, according to some embodiments. [Figure 73] FIG. 1 illustrates an ultra-thin device with a fused dot at the center of the device designed for implantation into a mouse, according to some embodiments. [Figure 74] 1A and 1B illustrate various configurations of a macro device frame for holding multiple cell-containment devices, according to some embodiments. [Figure 75A] FIG. 10 shows an ultra-thin device for human implantation with an array of fused spots that provides adhesion restriction, according to some embodiments. [Figure 75B] FIG. 1 illustrates a setup with a perforated metal platen to provide an external constraint for an ultra-thin device, according to some embodiments. [Figure 76A] 10A and 10B show the configuration of an ultra-thin device with an adhesion limiting portion. [Figure 76B] FIG. 1 illustrates the configuration of an ultra-thin device with an external porous restriction. [Figure 77] FIG. 10 shows the measured mass flow rate from filling an ultra-thin device for human implantation with a 3.3 mm dot pitch with and without an external porous restriction, according to some embodiments. [Figure 78] 75B is an H&E stain image of cell distribution throughout an ultra-thin device with adhesion constraints, similar to the device shown in FIG. 75A, according to some embodiments. [Figure 79A] 1A-1C illustrate exemplary configurations of hexagonal ultra-thin devices without dots, according to some embodiments. [Figure 79B] FIG. 10 is a detailed view of an exemplary configuration of a hexagonal ultra-thin device without dots, according to some embodiments. [Figure 80] 79A and 79B show the amount of cells that can be loaded into a single ultra-thin device according to some embodiments, when the device does not have dots, as in FIG. 79A, and when the device has a 3.3 mm dot array matrix, as in FIG. 79B. [Figure 81] 1A and 1B show two configurations of hexagonal ultrathin devices with a 3.3 mm dot array matrix, according to some embodiments, filled without any restrictions (A) and filled with porous platens spaced apart with 400 μm spacers (B). [Figure 82] 81A and 81B show the amount of cells that can be loaded into a single ultra-thin device according to some embodiments, without any restriction as in FIG. 81A, and with a porous restriction as in FIG. 81B. [Figure 83A] FIG. 10 shows an example of an ultra-thin device with a 2.6 mm dot pitch of a human single module design implanted in a minipig, according to some embodiments. [Figure 83B] FIG. 1 illustrates a targeted preperitoneal or subcutaneous implantation site in a minipig approximately 3 inches from the midline, avoiding the costal margin, according to some embodiments. [Figure 83C] 10A-10C illustrate subcutaneous incisions using electrocautery to prepare for device implantation, according to some embodiments. [Figure 83D] 10A-10C illustrate preperitoneal incisions with illuminated retractors to prepare for device implantation, according to some embodiments. [Figure 84A] 1A-1C illustrate examples of subcutaneous placement of ultra-thin devices, according to some embodiments. [Figure 84B] 1A-1C illustrate examples of preperitoneal placement of an ultra-thin device, according to some embodiments. [Figure 85]1 shows images of a minipig two weeks after subcutaneous (SQ) and preperitoneal (PP) implantation of an ultrathin device, according to some embodiments. [Figure 86A] 1 is an image of an exemplary positive mold for a channel array device, according to some embodiments. [Figure 86B] 1 is an image of an exemplary negative mold for a channel array device, according to some embodiments. [Figure 87] 1 is an image of a typical rodent channel array device with a manual fill tube inserted onto the frame, according to some embodiments. [Figure 88A] FIG. 10 illustrates the mass flow rate of a channel array device with a fill port, according to some embodiments. [Figure 88B] FIG. 10 illustrates mass flow rates of a channel array device with integrated fluid channels, according to some embodiments. [Figure 89A] 1 is an image of typical geometric parameters of a channel array device, according to some embodiments. [Figure 89B] FIG. 1 is an illustration of an exemplary channel assay device with a high aspect ratio (top) and a low aspect ratio (bottom), according to some embodiments. [Figure 89C] FIG. 1 is an illustration of an exemplary channel assay device with cylindrical design parameters, according to some embodiments. [Figure 90A] FIG. 1 is an illustration of a high density channel array (150 μm spacing), according to some embodiments. [Figure 90B] FIG. 1 is an illustration of a low density channel array (270 μm spacing), according to some embodiments. [Figure 91A] 1 is a detailed image of an exemplary laser-drilled channel array device, according to some embodiments. [Figure 91B] 1 is an image of an exemplary laser-drilled channel array device, according to some embodiments. [Figure 91C] FIG. 10 is a diagram for measuring the concentricity of an opening in a channel, according to some embodiments. [Figure 92] 1 is a graph of the measured concentricity of typical openings and channels. [Figure 93A] 1 is an image of an exemplary laser-drilled channel array device, according to some embodiments. [Figure 93B] 1 is an image of a sealing interface of a channel array device, according to some embodiments. [Figure 94A] 10A-10C are high-resolution images of vascularization around an implanted channel array device, according to some embodiments. [Figure 94B] 10 is a low magnification image of angiogenesis around an implanted channel array device, according to some embodiments. [Figure 95] FIG. 1 is a diagram of vascular host integration, according to some embodiments. [Figure 96A] FIG. 1 illustrates equilibrium O tension distribution within a typical channel array device, according to some embodiments. [Figure 96B] FIG. 1 illustrates equilibrium O2 tension distribution within a typical channel array device according to some embodiments. [Figure 97A] 1 is an image of thermoformed channels of an exemplary channel array device, according to some embodiments. [Figure 97B] 1 is an image of the internal chamber height of a single channel of a channel array device, according to some embodiments. [Figure 98] 1 is a graph measuring the fusion peel force of an exemplary membrane, according to some embodiments. [Figure 99A] 10A-10C are images of exemplary ruptured and fully formed membrane channels, according to some embodiments. [Figure 99B] 1 is an image of a thermoformed membrane according to some embodiments. [Figure 100] 1 is a bar graph illustrating the characteristic height of a typical membrane, according to some embodiments. [Figure 101] 10 is a bar graph illustrating the fusing peel force of a typical membrane formed using a fusing tool, according to some embodiments. [Figure 102A] 1 is a line graph of a differential scanning calorimetry analysis of an exemplary membrane formed using a fusion tool, according to some embodiments. [Figure 102B] 1A-1C are electron micrographs of exemplary sintered and unsintered membranes, according to some embodiments. [Figure 103] 1A-1C are illustrations of non-load cell enabled tools for heat fusing membranes by spot welding, according to some embodiments. [Figure 104] 10 is an image of a typical channel array device with non-uniform fusion using a non-load cell active position based fusion tool, according to some embodiments. [Figure 105A] 10A-10C are stress-strain curves of channel array curves formed using a non-load cell active position based fusion tool with non-uniform fusion, in accordance with some embodiments, where the fusion strength decreases across the channel array device. [Figure 105B] 1 is an image of a typical channel array device in a peel test, according to some embodiments. [Figure 106A] 10 is an image of a typical channel array device formed using a non-load cell active position based fusion tool, according to some embodiments, showing misalignment of the fused and laser drilled regions. [Figure 106B] 10 is an image of a typical channel array device formed using a non-load cell active position based fusion tool, according to some embodiments, where a leak was detected during post-fusion leak testing and repaired using adhesive. [Figure 107] 1 is an image of a typical channel array device with a single row formed using a load cell payload / force-based fusion tool, according to some embodiments. [Figure 108] 10 is a bar graph measuring fusion strength / peel force (N) versus fusion time for a channel array device formed using a load cell payload / force-based fusion tool, according to some embodiments. [Figure 109]An image of a typical channel array device (left) with an array design and a fusion strength of approximately 0.4-0.6 N, and an image of a typical channel array device (right) with a single row design and a fusion strength of approximately 0.45 N, according to some embodiments. [Figure 110] FIG. 1 shows stress-strain curves of an exemplary channel array device with a first deforming membrane and a second flat membrane, according to some embodiments. [Figure 111] 10A-10C are images of a typical channel array device formed using 2X, 4X, 6X, or 8X fused dots, according to some embodiments. [Figure 112] 1 is a bar graph measuring fusion strength / peel force (N) versus fusion strike count, according to some embodiments, used to fuse a first deformed membrane to a second flat membrane using a load cell payload / force-based fusion tool with a fusion temperature of 800°F, a fusion time of 0.05 seconds, and a fusion force of 6 lbs. [Figure 113] 1 is a bar graph measuring fusion strength / peel force (N) versus fusion force for a typical channel array device, according to some embodiments, where the fusion force is for fusing a first deformed membrane with a second flat membrane at a fusion temperature of 800°F, a fusion time of 0.05 seconds, and fusion dot count of 1x. [Figure 114] 10 is an image of a typical channel array device with a first deformed membrane and a second flat membrane formed using a load cell enabled fusion tool in a tensile test according to some embodiments, where membrane drag is present resulting in a double fused dot. [Figure 115] 1 is a bar graph showing fusion strength / peel force (N) versus target fusion force using a 4X fusion hit point of an exemplary channel array device, according to some embodiments. [Figure 116] 1 is a bar graph showing the fusion strength / peel force (N) of a typical channel array device, according to some embodiments. [Figure 117A]1 is an image of a typical channel array device with a 3x3 array of simultaneous dots according to some embodiments herein, according to some embodiments. [Figure 117B] 1 is a bar graph showing the fusion strength / peel force (N) of a typical channel array device, according to some embodiments. [Figure 118] 1 is a bar graph showing the fusion strength / peel force (N) of a typical channel array device, according to some embodiments. [Figure 119] 10 is an image of a typical channel array device in a peel test, where the fusion point remains intact while the membrane tears, according to some embodiments. [Figure 120] 10A-10C are stress-strain curves for exemplary channel array devices formed using non-load cell enabled or load cell enabled fusion tools, according to some embodiments. [Figure 121] 10 is an image of fused and unfused regions of a membrane using a load cell enabled fusion tool, according to some embodiments. [Figure 122A] 10 is an image of a channel of a typical channel array device formed using a load cell enabled fusion tool, according to some embodiments, showing the average seal / ledge size at the fusion point. [Figure 122B] 1 is an image of a typical channel array device formed using a load cell enabled fusion tool, according to some embodiments, showing the concentricity between the laser drilled holes at the fusion point and the fused area. [Figure 123] 1 is a bar graph showing fusion / peel forces (N) of pre-laser channel array devices formed using generation 1 and generation 2 fusion tools, according to some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0022] The present disclosure relates generally to medical devices and methods, which may include cell-containing devices, related devices, and methods of making and using such devices, which may be useful for providing improved mass transport between environments external and internal to the device.

[0023] In some cases, the cell-containment device may include a high surface area-to-volume ratio. A high surface area-to-volume ratio may enable the device to achieve improved mass transport into and / or out of the device, thereby increasing the effectiveness of nutrient delivery to cells within the device. In some cases, the cell-containment device may include a first surface. The first surface may define an exterior surface of the device and have a surface area. The cell-containment device may also include a second surface opposite the first surface, defining an interior surface of the device. The cell-containment device may also include a compartment enclosed within the second surface, providing a volume for containing cells within the device. The device may include a single, continuous, open space having a volume. The first or second surface of the device may include multiple nodes interconnected by multiple fibrils. The device may also include multiple channels running through the cross-section of the device. The channels may provide a high surface area-to-volume ratio for the cell-containment device. Each channel may have a diameter of 400 μm or more, measured at the narrowest point within the channel. Each of the plurality of channels may be separated from the others by a distance not exceeding 450 μm. The device may have a thickness greater than 250 μm, measured along a cross-section of the device. In some cases, the channels may be such that the thickness of the cell-containment device does not pose a problem for mass transport (e.g., of nutrients) into and / or out of the device. The first or second surface of the device may include PVDF, PTFE, ePTFE, PCL, PE / PES, PP, PS, PMMA, PLGA, or PLLA. The device may further include a frame configured to receive one or more cell-containment devices. The frame may include a flexible mechanism to prevent buckling of the cell-containment devices. The device may include a coating with a hydrophilic polymer. The volume for containing cells may be inversely proportional to at least one of a diameter of the plurality of channels and a number of channels per area of ​​the device. The surface area-to-volume ratio of the device may be directly proportional to at least one of a diameter of the plurality of channels and a number of channels per area of ​​the device.The surface area to volume ratio of the device may allow for greater mass transport into and / or out of the device.

[0024] In some cases, the cell-containment device may have a short oxygen diffusion distance. This short oxygen diffusion distance may be independent of the dimensions of the cell-containment device (e.g., its thickness). For example, the cell-containment device may include a base and a top surface opposite the base. A compartment for containing cells may be enclosed between the base and the top surface, and in some cases, the cell may rely on mass transport from the outside to access nutrients for life support. The height extending from the base to the top surface along the cross-section of the device may be high (e.g., greater than 300 μm). Regardless, the oxygen diffusion distance for the device may be less than 150 μm. In some cases, this may be possible due to various channels or lumens in the device. The channels may in some cases extend across the cross-section of the device, allowing the device to have a short oxygen diffusion distance regardless of the thickness of the device. The base may be substantially flat.

[0025] The cell containment devices described herein may be fabricated using two membranes. In some steps, a first membrane may be prepared using various materials described herein. In some cases, the first membrane may be placed in a chamber where the temperature and / or pressure may be set and / or adjusted to a predetermined value. The first membrane may be deformed (e.g., to form a compartment or volume for containing cells). A second membrane may then be fused to the first membrane to form the compartment. Optionally, apertures may be formed in the device channels to allow continuous passage through the cell containment device using various means, such as a laser. In some cases, the temperature and / or pressure may be adjusted to deform the first membrane or to fuse the first membrane to the second membrane. The temperature and / or pressure used in each of these processes may be an integral part of fabricating the cell containment device. Adjusting the temperature and / or pressure in the deformation or fusion region may control the characteristics of the feature. In some cases, increasing the temperature and / or pressure in the deformation or fusion region may increase the depth of the feature. In some cases, the first membrane may be embossed after deformation. In some cases, after fusing, the device may have a substantially flat surface and an embossed surface opposite the substantially flat surface. Figure 1 shows a high magnification image of a cell-containment device formed using a PVDF membrane, the cell-containment device having a regularly spaced array of apertures within the channels of the device. Deforming the membrane may also (or alternatively) include fibrillation, where nodes from one membrane unwind and interact with fibrils from another membrane to form entanglements and seals.

[0026] As mentioned above, encapsulating cells that produce various biological products in a device can be very useful, for example, for delivering therapeutics. Herein, the device may be referred to as a cell-containing device, and a matrix may be contained within the device. The matrix can be a biomaterial in the interior space of the cell-containing device. The matrix may include a hydrogel, a porous sponge, an electrospun fiber, a polymeric material, or other porous biocompatible material. The matrix may further include growth factors, nutrients, or other agents that enhance cellular activity and biological product synthesis. The matrix may also include cells or other protein expression systems (e.g., cell-free expression systems) that enable biological product production. Increasing matrix thickness can further reduce the availability of oxygen and other nutrients away from the peripheral surface of the matrix. For example, this can occur when oxygen or nutrient transport relies primarily on passive transport or diffusion. This can result in very little or no nutrients being delivered to regions within the matrix far from the surface. Nutrient availability can also be depleted by cellular consumption as nutrients pass through the matrix. The reduction in nutrients within the matrix can be problematic for cells or systems with high demands for oxygen or other nutrients. Because cells become highly active after stimulation, oxygen consumption by cells can increase from basal conditions upon stimulation. The reduced availability of nutrients important for cell viability and activity can limit the increase in size of the matrix and the cell-containing device in which it resides. Mass transport limitations within the matrix can limit the ability to increase device size and thus biological product output. Reducing cell density within the matrix to reduce consumption may generally be undesirable because it is impractical to increase matrix dimensions to offset the decrease in cell density.

[0027] The design of the cell-containment device may be adjusted to control the surface area to volume (SA:V) ratio of the device. In some cases, designs may be provided to increase the SA:V ratio of current devices. Increasing the SA:V ratio may help improve transport (e.g., of nutrients) to interior regions of the device. One such design to increase the SA:V ratio may be the incorporation of channels and / or other geometric shapes through the matrix and cell-containment device. In some cases, channels may help increase the SA:V ratio of the device and the matrix contained within the device. Channels may include through-holes or lumens that run completely from one side of the cell-containment device to the other. The channels may be arranged in a pattern or may be provided without a distinct pattern. As an example, the channels may be provided in an array pattern with a predetermined spacing between the channels. Alternatively, the channels may be provided in a random pattern.

[0028] The inclusion of channels in a cell-containment device may facilitate scaling the size of the device compared to devices without channels. Figure 3 illustrates zones of varying oxygen pressure within a bilayer flat sheet and a channel array device. As shown in Figure 3, a device 300 with a channel array 301 (also referred to herein as a channel array device) can have channels running through the matrix and the cell-containment device. A cell-containment device with channels 300 may be of any thickness, but may still avoid having zones of low oxygen or nutrients. Conventional bilayer flat sheets may be limited in thickness to 300 μm or less to avoid zones of low oxygen or nutrients. A cell-containment device with channels may provide improved mass transport and increased angiogenic potential compared to bilayer flat sheet designs or other channel-free designs. As a result of these features, the size of a channel array device may be more easily scaled than devices without channels.

[0029] Cell-containing devices with channels (also referred to as channel array devices) can increase the surface area for mass transport. Increased mass transport can increase the overall diffusion flux throughout the matrix and device. This increase can increase the dimensions of the matrix and device while reducing areas of very low or no nutrients. As a result, the maximum oxygen diffusion distance of the device can be less than 150 μm. Optionally, cell-containing devices with channels can also increase angiogenesis potential. Figure 4 illustrates the surface area and angiogenesis potential of a flat configuration device and a channeled device. Figure 5 illustrates the increased angiogenesis with a flat configuration device or a channeled device. Figure 6 shows a computer-aided design (CAD) rendering of a hexagonal device with increased channel size but a similar SA:V ratio. As shown in Figure 4, a channeled device can support a higher number of cells per area than a flat configuration device because it provides sufficient nutrients to the cells throughout the matrix to support their viability and activity. Compared to devices in a flat configuration, when implanted in vivo, the channels allow vasculature to grow around and through the channels. In flat configuration devices, vascularization is limited to the top and bottom surfaces of the device, as shown in Figures 4 and 5. In some cases, channel characteristics and / or the number or density of channels may increase vascularization. For example, a channel diameter may be the cross-sectional distance of the channel. A channel diameter may be measured at its narrowest point in a cross-section parallel to the plane of the second membrane. The channel density of a device may be the number of channels per area of ​​the device. The channels may be arranged so that there are a certain number of channels per area along the cross-section of the device. The size, number, and / or density of channels as described herein may increase vascularization and increase the mass transport of nutrients to cells. A cell-containing device may protect the matrix and cells or other contents of the matrix from direct contact with the vasculature within the channels.The design of the array (eg, its channel size and spacing) can be altered to vary the surface area and vasculature growth pattern and potential.

[0030] The dimensions of the channel may be adjusted to control the volume and SA:V ratio within the cell-containment device. In some embodiments, the diameter of the channel may be increased to decrease the volume within the cell-containment device. As a result, increasing the diameter of the channel may increase the SA:V ratio for the cell-containment device. In some embodiments, the diameter of the channel may be decreased to increase the volume within the cell-containment device. As a result, decreasing the diameter of the channel may decrease the SA:V ratio for the cell-containment device.

[0031] The matrix can be connected as one or more pieces contained within the cell-containment device. The matrix can include a single continuous piece within the cell-containment device. The matrix can also include channels running through its thickness where channels run through the cell-containment device. The matrix can be a biomaterial within the interior space of the cell-containment device. The matrix can include hydrogels, porous sponges, electrospun fibers, polymeric materials, or other porous biocompatible materials. The matrix can further include growth factors, nutrients, or other agents that enhance cellular activity and synthesis of biological products. The matrix can also include cells or other protein expression systems that enable production of biological products. Figure 7 shows a rendering of a cell-containment device and a scanning electron micrograph of a cross-section of the cell-containment device with a connected interior that may contain the matrix.

[0032] The cell containment device may have various lengths, widths, and heights appropriate for the application. The length may be the longest dimension on the top surface of the device. The width may be the dimension perpendicular to the length on the top surface. The height of the device may refer to the thickness of the device and may extend from the base to the top surface along the cross-section of the device. In some cases, the length of the cell containment device may be about 0.2 cm or more, 0.5 cm or more, 1.0 cm or more, 1.5 cm or more, 2.0 cm or more, 2.5 cm or more, 3.0 cm or more, 4.0 cm or more, 5.0 cm or more, 6.0 cm or more, 7.0 cm or more, 8.0 cm or more, 9.0 cm or more, 10 cm or more, 20 cm or more, 30 cm or more, 40 cm or more, 60 cm or more, 100 cm or more, 120 cm or more, 150 cm or more, 180 cm or more, or 200 cm or more. In some cases, the width of the cell containment device may be about 0.2 cm or more, 0.5 cm or more, 1.0 cm or more, 1.5 cm or more, 2.0 cm or more, 3.0 cm or more, 4.0 cm or more, or 5.0 cm or more, 6.0 cm or more, 7.0 cm or more, 8.0 cm or more, 9.0 cm or more, or 10 cm or more. In some cases, the height of the cell containment device may be about 100 μm or more, 200 μm or more, 300 μm or more, 400 μm or more, 500 μm or more, 600 μm or more, 700 μm or more, 800 μm or more, 900 μm or more, 1000 μm or more, 0.2 cm or more, 0.3 cm or more, 0.4 cm or more, 0.5 cm or more, 0.6 cm or more, 0.7 cm or more, 0.8 cm or more, 0.9 cm or more, 1.0 cm or more, 2 cm or more, 3 cm or more, 4 cm or more, or 5 cm or more (measured along the cross section of the device).

[0033] The cell containment device may be designed to have an SA:V ratio appropriate for transporting nutrients and desired products through the device. In some cases, the SA:V ratio may be 50 cm -1 In other cases, the SA:V ratio may be about 20 cm or more. -1 Over 40cm -1 Over 60cm -1 More than 80cm -1 More than 100cm -1 Over 120cm -1 Over 150cm -1 More than 200cm-1 More than 250cm -1 More than 300cm -1 The maximum oxygen diffusion distance of the device may be less than 50 μm, less than 100 μm, less than 150 μm, less than 200 μm, less than 250 μm, less than 300 μm, less than 350 μm, less than 400 μm, less than 450 μm, or less than 500 μm.

[0034] In some cases, the channel 751 of the cell containment device 750 may be generally cylindrical in shape. Illustrated in Figures 3, 6, and 7 is a cylindrical channel within a cell containment device. For purposes of explanation, a cylindrical channel is primarily described herein, but it is understood that the channel may be any shape; for example, the walls of the channel may be generally straight, curved, barrel-shaped, or other shapes. In some cases, the cross-sectional area of ​​the channel may vary from the top of the first membrane 711 to the base of the second membrane 720 of the cell containment device. In some cases, the device may include a fused portion 754. For example, the device may have the first membrane 711 fused to the second membrane 720 to provide a compartment 753 within the cell containment device. Cells may be loaded into the compartment 753. In some cases, the fused portion of the channel (e.g., where the first membrane meets the second membrane) may be generally circular or other shape. As described elsewhere herein, in some cases, openings 752 may be formed in the fused portions of the membrane to provide channels that run through the cell containment device. A channel may include a cross-sectional distance, or diameter, as described herein. Alternatively, the cross-sectional distance of a channel may refer to the diameter when the channel is generally circular in cross section. A channel diameter may be measured at its narrowest point in a single cross-section parallel to the plane of the second membrane. Alternatively, the diameter may be measured as the average channel width along the height of the channel or device. Alternatively, the diameter may be measured at its widest point in a single cross-section parallel to the plane of the second membrane. In some cases, a channel diameter can be 100 μm or more, 200 μm or more, 300 μm or more, 400 μm or more, 500 μm or more, 600 μm or more, 700 μm or more, 800 μm or more, 900 μm or more, or 1000 μm or more. Optionally, the height of the channel may be proportional to the diameter.In some cases, the height to diameter ratio of the channels may be about 0.1 or more, 0.2 or more, 0.3 or more, 0.4 or more, 0.5 or more, 0.6 or more, 0.7 or more, 0.8 or more, 0.9 or more, 1.0 or more, 1.1 or more, 1.2 or more, 1.3 or more, 1.4 or more, 1.5 or more, 1.6 or more, 1.7 or more, 1.8 or more, 1.9 or more, 2.0 or more, 3 or more, 4 or more, 5 or more, 6 or more, 7 or more, 8 or more, 9 or more, or 10 or more.

[0035] A plurality of channels may run through the cross section of the device. The channels may be arranged such that there are a number of channels per area along the cross section. As used herein, the number of channels per area may be referred to as the channel density of the device. In some cases, the number of channels per area along the cross section is about 10 channels / cm. 2 Over 15 channels / cm 2 Over 20 channels / cm 2 Over 25 channels / cm 2 Over 30 channels / cm 2 Over 35 channels / cm 2 Over 40 channels / cm 2 Over 45 channels / cm 2 Over 50 channels / cm 2 Over 60 channels / cm 2 Over 70 channels / cm 2 Over 80 channels / cm 2 Over 90 channels / cm 2 Over 100 channels / cm 2 Over 110 channels / cm 2 Over 120 channels / cm 2 Over 130 channels / cm 2 Over 140 channels / cm 2 Over 150 channels / cm 2 Over 175 channels / cm 2 or more than 200 channels / cm 2 It may be more than that.

[0036] The channels can be spaced apart so as to eliminate regions receiving low or no oxygen or other nutrients important to cell viability and activity. In some cases, the channels can be spaced apart or separated from one another by a distance of about 100 μm or less, 200 μm or less, 300 μm or less, 400 μm or less, 500 μm or less, 600 μm or less, 700 μm or less, 800 μm or less, 900 μm or less, or 1000 μm or less. Optionally, the distance can be measured from the center of one channel to the center of an adjacent channel. In some cases, the cell-containing device can have a channel spacing of one distance across the device. Alternatively, the cell-containing device can have multiple different channel spacing distances across the cell-containing device. In some cases, the channels can be arranged in a regular array with a regular channel spacing distance across the device. For example, the channels can be arranged in a hexagonal array, as illustrated in FIG. 6. Alternatively, other arrangements of channels (e.g., circular, square, etc.) can be provided.

[0037] In some cases, the lumen area of ​​the channel can be proportional to the cross-sectional area of ​​the channel. The lumen may be cut off from a portion of the fused region of the device. In some cases, the lumen area is about 0% or more, 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 99% or more of the cross-sectional area of ​​the channel.

[0038] A plurality of lumens may run through the cross section of the device. The lumens may be arranged such that there are a number of lumens per area along the cross section. As used herein, the number of lumens per area may be referred to as the lumen density of the device. In some cases, the number of lumens per area along the cross section is about 10 lumens / cm. 2 More than 15 lumen / cm 2 More than 20 lumens / cm 2 More than 25 lumen / cm 2 More than 30 lumen / cm 2 More than 35 lumen / cm 2 More than 40 lumen / cm 2 More than 45 lumen / cm2 More than 50 lumen / cm 2 More than 60 lumen / cm 2 More than 70 lumen / cm 2 More than 80 lumen / cm 2 More than 90 lumen / cm 2 More than 100 lumen / cm 2 More than 110 lumen / cm 2 More than 120 lumen / cm 2 More than 130 lumen / cm 2 More than 140 lumen / cm 2 More than 150 lumen / cm 2 More than 175 lumen / cm 2 or more than 200 lumens / cm 2 It may be more than that.

[0039] The channel array device can be adapted for a variety of in vivo and in vitro applications. In one example, the device can house functional cells or expression systems, such as pancreatic islet cells, within its matrix. The matrix can include isolated pancreatic islet cells, cells isolated from the pancreas, cells isolated from tissue, stem cells, stem cell-derived cells, induced pluripotent cells, differentiated cells, transformed cells, or expression systems capable of synthesizing one or more biological products. Optionally, the matrix can include a second type of cells that support the first type of cells synthesizing one or more biological products. The cells can be encapsulated prior to placement within the matrix. The cells can be encapsulated in microcapsules or conformally coated. The device can be used to supplement pancreatic islet cell function.

[0040] The design of the channel array within the device can affect the angiogenic potential, or the amount of vasculature that can grow through or around the device. Channels within the device can be designed to increase angiogenic potential. Such devices can improve nutrient transport and reduce the risk of hypoxia to cells housed within. Such devices can be larger in size and accommodate larger matrices with cells or other expression systems. Such improved transport devices can increase cell viability to more than one year from initial generation. In some cases, cell viability can exceed 1 month, 2 months, 4 months, 6 months, 8 months, 10 months, 12 months, 14 months, 16 months, 18 months, 20 months, 22 months, 24 months, 36 months, 48 ​​months, or more.

[0041] Changes in the surface area of ​​the channel array device can affect the kinetics of biological products. Biological products may include human cells, animal cells, or genetically modified cells. Due to the increased surface area, channel array devices can increase biological product production and release. Figure 32 illustrates the effect of device design on insulin response and surface area to volume ratio. As shown in Figure 32, channel array devices can increase biological product production and release compared to similarly sized devices without a channel array. Channel array devices can have a higher SA:V ratio than similarly sized devices without a channel array. Increasing the SA:V ratio in a channel array device can enable higher biological product flux than a similarly sized device without a channel array. For matrices with functional cells such as pancreatic islet cells, increasing the SA:V ratio can enable a higher islet equivalent (IEQ) per area. In some cases, this can result in increased insulin production and increased insulin flux. Figure 6 shows renderings of hexagonal channel array devices with similar SA:V ratios but with increased sizes. Shown in Figure 18 is a rendering of cell-containing devices with similar overall dimensions but varying channel dimensions to achieve different SA:V ratios.

[0042] In some cases, the devices described herein can be assembled and / or mounted on a frame, as further described below. The frame may be configured to receive one or more cell-containment devices. Optionally, the device can be mounted on a subframe in addition to the frame. The frame can provide flexible support for the device (e.g., a channel array device) of the present disclosure. The frame can prevent unwanted bending of the device. The frame can have one or more flexibility mechanisms that prevent buckling of the cell-containment device. The flexibility mechanisms can prevent buckling of sensitive device regions within the device. The flexibility mechanisms can have cutouts that allow the frame to flex. The flexibility mechanisms allow the assembly to curve along with the tissue at its implantation site. Alternatively, the devices described herein can be used without a frame. For example, the device can be implanted into an individual alone without any structural support or frame. Figure 50 shows a prototype of three cell-containment devices assembled on a frame for human use. The devices and the frame that holds the devices can be formed using materials that elicit a low foreign body response. Materials for the device and frame can be selected to reduce inflammation or fibrosis. The device and frame can be used in conjunction with anti-inflammatory or anti-macrophage therapy to further reduce the foreign body reaction.

[0043] The cell containment device can be fabricated using a simple process. In some cases, the cell containment device can be fabricated by deforming a first membrane into the shape of the channel array and fusing a second membrane to the deformed first membrane. In some cases, a tool can be used as a guide to deform the first membrane. In some cases, a tip in the shape of the channel can be used to deform the membrane where the tip contacts the membrane.

[0044] The membrane may comprise a biocompatible porous material that allows diffusion of a biological product of about 6 kDa or less after the manufacturing step. Alternatively, the material for the membrane allows for diffusion of a biological product of about 2 kDa or less, about 4 kDa or less, about 6 kDa or less, about 8 kDa or less, about 10 kDa or less, about 12 kDa or less, about 14 kDa or less, about 16 kDa or less, about 18 kDa or less, about 20 kDa or less, about 25 kDa or less, about 30 kDa or less, about 35 kDa or less, about 40 kDa or less, about 45 kDa or less, about 50 kDa or less, about 60 kDa or less, about 70 kDa or less, about 80 kDa or less, about 90 kDa or less, about 100 kDa or less, about 200 kDa or less, about 300 kDa or less, about 400 kDa or less, or about 500 kDa or less. The average pore size of the material for the membrane, after the manufacturing step, may be about 1 nm or less, about 2 nm or less, about 3 nm or less, about 4 nm or less, about 5 nm or less, about 6 nm or less, about 7 nm or less, about 8 nm or less, about 9 nm or less, about 10 nm or less, about 12 nm or less, about 14 nm or less, about 16 nm or less, about 18 nm or less, or about 20 nm or less.

[0045] The fabrication steps of forming, joining, and cutting the membrane can be performed using one or more devices, such as a membrane forming or fusing device. The device can be formed by a three-dimensional printing process, microfabrication, or other machining techniques. In some cases, the device can be modular. In some cases, the shape of the device can dictate the dimensions and / or shape of the channels. The device can include a positive and / or negative mold for the membrane (e.g., the first membrane described above). The device can be formed of metal.

[0046] The device may include a platform for the membrane. In some cases, the platform may include a mold (e.g., a negative mold) for the cell-containment device. In some cases, the platform may include a plate. The platform may further include cutouts or holes into which the membrane may be molded. The cutouts may affect the diameter (or lumen) of the channel to be formed for the cell-containment device. In some cases, the platform may be positioned at a height and offset from a different surface. The different surface may be a surface against which the membrane is configured to be pressed using a device described herein. This offset height can determine the depth of the channel in the membrane (e.g., the first membrane).

[0047] The device may include various tools. In some cases, the tool may include a tip or multiple tips for deforming and / or fusing the membrane. The tool may deform the first membrane by depressing a portion of the first membrane. The tool may include a substantially flat surface configured to be parallel to the first membrane and one or more protrusions on the surface that can deform or depress a portion of the first membrane. In some cases, the tool may include multiple protrusions. Each of the multiple protrusions may include a cylinder.

[0048] A machine for manufacturing a cell containment device may be configured to support a membrane (e.g., the first membrane described above). The platform may include holes in or below the support, and a second membrane may be placed thereon. A tool including multiple protrusions may be configured to mate with the platform. In some cases, the tool may press down on the support platform. Optionally, the tool's protrusions may be configured to mate with the holes in the platform. In some cases, the first membrane may be placed on the platform (e.g., above the holes). The tool may press down on the first membrane, and may push a portion of the membrane through the holes, thereby forming a deformed membrane. In some cases, the deformed membrane may be fused together with the second membrane using the correct pressure and / or temperature as described herein.

[0049] The molding machine chamber holds various equipment (e.g., the platform and tooling described above) and membranes for manufacturing the cell-containment device. The chamber may be sealed. The chamber may be configured to hold the platform and / or tooling. The chamber may provide a predetermined or desired temperature necessary for membrane fusion to occur. The molding machine may have a sealed chamber with a gas inlet and / or a vent. The molding machine may be configured to hold the membrane. For example, the molding machine may include a platform. A flat first membrane can be placed in the sealed chamber of the molding machine. While the vent is closed, nitrogen gas or other gas can be introduced into the sealed chamber through the gas inlet to reach a predetermined pressure, either continuously or simultaneously with heating the chamber to a predetermined temperature. A tool can be used to deform the membrane and produce a deformed first membrane. In some cases, the vent can be opened to vent the sealed chamber after the deformation step is complete.

[0050] As previously described, a tool may be used to deform the first membrane. The tool may include a single tip or multiple tips. In some cases, a tip in the shape of a channel may be used to deform the membrane where the tip contacts the membrane. The tip may be cylindrical, conical, tapered, cylindrical, or other shape. The tip may have a contact area at the free end. The contact area of ​​the tip can contact the membrane. The tip area may be about 0.5 mm 2 Below, approximately 0.6mm 2 Below, approximately 0.8mm 2 Below, approximately 1.0mm 2 Below, approximately 1.2mm 2 Below, approximately 1.4mm 2 Below, approximately 1.6mm 2 Below, approximately 1.8mm 2 Below, approximately 2.0mm 2 Below, approximately 2.2mm 2 Below, approximately 2.4mm 2 Below, approximately 2.6mm 2 Below, approximately 2.8mm 2 Below, approximately 3.0mm 2 Below, approximately 4.0mm 2 Less than or equal to 5.0 mm 2 The area of ​​the tip may be about 0.2 mm 2 or more, about 0.3mm 2 or more, about 0.4mm 2 More than 0.5mm 2 More than 0.6mm 2 More than 0.7mm 2 More than 0.8mm 2 More than 0.9mm 2 More than 1.0mm 2 More than 1.2mm 2 or more, about 1.4mm 2 More than 1.6mm 2 More than 1.8mm 2 Over 2.0mm 2 More than 2.2mm 2 or more, about 2.4mm 2 More than 2.6mm 2 More than 2.8mm 2 Over 3.0mm2 Over 4.0mm 2 More than or about 5.0 mm 2 The vertical distance traveled by the tip after initial contact with the membrane may help determine the height of the channel. The vertical distance traveled by the tip after initial contact with the membrane may be adjusted to achieve a predetermined height of the channel.

[0051] The first membrane can be deformed into the shape of the channel array. The first membrane can be deformed by thermoforming. The first membrane can be deformed by expansion-based thermoforming. Deforming the first membrane can include depressing a portion of the first membrane with a tool. In one example, the first membrane can be placed in a sealed chamber of a molding machine using a mold to form the channel array. The first membrane can be a flat sheet before the deformation step. The molding machine with the first membrane can be heated to a predetermined temperature critical for deformation. While the vent is closed, gas can be introduced into the sealed chamber through the gas inlet sequentially and / or simultaneously to reach a predetermined critical pressure and produce a deformed first membrane. In some cases, pressure can be applied by pumping in nitrogen gas. The critical pressure can be applied as a positive or negative pressure. After the deformation step is completed, the vent can be opened to vent the sealed chamber. Figure 8 shows a close-up of the membrane deforming from a flat configuration to a formed configuration with channels. A flat first membrane 810 is placed on a mold 820 within a sealed chamber. After heating the chamber to a predetermined temperature and applying a predetermined pressure to the membrane, the first membrane 811 deforms around the mold to form channels. In some embodiments, thermoforming can create specific internal shapes of set heights and aspect ratios that enable and improve engraftment and vascularization.

[0052] After the first membrane is deformed, a second membrane can be fused to the first membrane to form a cell-containing device. The second membrane can be substantially flat. The second membrane can be placed on one side of the deformed first membrane. The two membranes can be heated to a critical temperature for fusion. Once a predetermined temperature and / or pressure for fusion is reached, the two membranes can be compressed and / or fused together. Compression of the two membranes can be performed at selected locations across the first membrane. Compression can be facilitated by a mold or plate having the shape and spacing features of the channel array. Heating can be performed in an oven. Alternatively, heating can be performed by a tool with a heating element. The fused first and second membranes can form a fusion at their interface to form compartments. The compartments can be interconnected, resulting in a device comprising a single continuous open space having a volume. The compartments can be enclosed between the base and top surface of the device and can contain cells. FIG. 9 shows the fusion between the formed first membrane 1211 and the flat second membrane 1220, and the resulting device 1250 with the fused first and second membranes.

[0053] The structure of the first and second membranes may vary depending on the manufacturing process steps. Figure 10 shows cross-sections of the cell-containment device along various portions of the cell-containment device. The ultrastructure of the PVDF membrane varies from primarily nodes to primarily elongated fibrils (where the material has deformed or fused). The first or second membrane may contain multiple nodes interconnected by multiple fibrils. During the deformation or fusion step, some of the node structures may transform into elongated fibrils. The level of heat or pressure to which the membrane is exposed may affect the number of node structures. Generally, areas of the membrane that have not deformed or fused (e.g., the top surface or top of the channel) may observe more nodes and fewer fibrils. Generally, areas of the membrane that have undergone deformation or fusion (e.g., the bottom or middle of the channel) may observe more fibrils than membranes that have undergone less deformation or fusion. Generally, regions of the membrane that have undergone deformation or fusion (e.g., the bottom of the channel or the middle channel) will have fewer observed knots than membranes that have undergone less deformation or fusion. Nodes may be reservoirs of material that can be stretched into fibrils under heat and / or pressure during the deformation or fusion step. Without material in the structure to transition from nodes to fibrils, the membrane may crack during the deformation or fusion step. It is important to perform the deformation and fusion without causing membrane cracks. The number of nodes and fibril structures and the change in the number of nodes and fibril structures may be specific to the membrane material.

[0054] The first and second membranes can be fused without additional adhesive. The first and second membranes can self-seal without adhesive at critical temperatures for fusion. Fusion between the first and second membranes can achieve high seal integrity. Visualizing the seam between the fused first and second membranes can be difficult; as shown in Figure 11, the fused portions of the first and second membranes can appear as one continuous membrane under scanning electron microscopy. High seal integrity may allow the cell-containment device to be filled at higher pressures. Optionally, an adhesive can be placed between the first and second membranes before fusion. In some cases, the adhesive can be pressure- and / or temperature-sensitive. Figure 38 shows a tool for sealing the perimeter of the device. Figure 39 shows a scanning electron micrograph of the peripheral edge of a device sealed at 345°C for 0.5 seconds. The seam between the membranes is difficult to identify at the ultrastructural level.

[0055] The critical pressure and temperature ranges may vary depending on the material used as the membrane. For example, for ePTFE, there may be a desired temperature at which the membrane must retain its deformed shape. In some cases, the desired temperature may be the temperature at which the material is sintered. In some cases, the critical pressure and / or temperature range may be different for each manufacturing step. For the deformation step, the critical pressure may be less than 10 psi, less than 20 psi, less than 30 psi, less than 40 psi, less than 50 psi, less than 60 psi, less than 70 psi, less than 80 psi, less than 90 psi, less than 100 psi, less than 110 psi, less than 120 psi, less than 130 psi, less than 140 psi, less than 150 psi, less than 160 psi, less than 170 psi, less than 180 psi, less than 190 psi, or less than 200 psi. For the deformation step, the critical temperature may be less than 100°C, less than 110°C, less than 120°C, less than 130°C, less than 140°C, less than 150°C, less than 160°C, less than 170°C, less than 180°C, less than 190°C, or less than 200°C. For the deformation step, the critical temperature may be less than 210°C, less than 220°C, less than 230°C, less than 240°C, less than 250°C, less than 260°C, less than 270°C, less than 280°C, less than 290°C, less than 300°C, less than 310°C, less than 320°C, less than 330°C, less than 340°C, less than 350°C, less than 360°C, less than 370°C, less than 380°C, less than 390°C, less than 400°C, less than 410°C, less than 420°C, or less than 430°C. For the fusion step, the critical temperature may be less than 150°C, less than 160°C, less than 170°C, less than 180°C, less than 190°C, less than 200°C, less than 210°C, less than 220°C, less than 230°C, less than 240°C, less than 250°C, less than 260°C, less than 270°C, less than 280°C, less than 290°C, less than 300°C, less than 310°C, less than 320°C, less than 330°C, less than 340°C, less than 350°C, less than 360°C, less than 370°C, less than 380°C, less than 390°C, less than 400°C, less than 410°C, less than 420°C, or less than 430°C.For the fusion step, the critical pressure may be less than 10 psi, less than 20 psi, less than 30 psi, less than 40 psi, less than 50 psi, less than 60 psi, less than 70 psi, less than 80 psi, less than 90 psi, less than 100 psi, less than 110 psi, less than 120 psi, less than 130 psi, less than 140 psi, less than 150 psi, less than 160 psi, less than 170 psi, less than 180 psi, less than 190 psi, or less than 200 psi. The combination of critical pressure and critical temperature may need to be customized for each manufacturing step and material used. There may be a critical pressure and / or temperature range for each material, which defines the range within which the material can deform without secondary rearrangement of the crystalline domains of the polymer. Within the critical pressure and temperature range, nodes in the thermoelastic material may expand into a more fibrillar structure to accommodate the new deformed or fused shape. However, outside the critical pressure and temperature range, the material may become crystalline and crack during deformation or fusion.

[0056] Membranes may crack if deformed or fused outside the critical temperature and pressure ranges for deformation or fusion. Selecting temperatures and pressures outside the critical temperature and pressure ranges for deformation may result in the first membrane not fusing or fusing insufficiently to the second membrane during the fusing step. This crack in the first membrane may not become apparent until the fusing step. Outside the critical temperature or pressure range, the membrane material may increase in crystallinity. The material for the first membrane with increased crystallinity may not fuse or fusing insufficiently to the material for the second membrane. Relative crystallinity can be measured using differential scanning calorimetry (DSC) to calculate the transition enthalpy of the material. Secondary peaks in DSC heat flow measurements of a membrane may indicate a rearrangement of the membrane's crystalline structure and may indicate that the membrane may not easily fuse to another membrane. This rearrangement may occur without an increase in relative crystallinity. The rearrangement may also occur without a decrease in relative crystallinity. The alignment of the crystalline domains of the membrane is an important factor in fusion, and potential rearrangements of the crystalline structure may not allow for chain entanglement of the crystalline domains with another membrane during fusion. Figure 15 shows another example of DSC heat flow measurements of a membrane. The DSC heat flow measurements of the membrane deformed at 100 psi and 160°C maintained a shoulder peak, whereas the baseline PVDF membrane did not significantly change its crystalline structure and fused with a second membrane. The heat flow measurements of the membrane deformed at 100 psi and 173°C and quenched showed a distinct secondary peak in the initial melting endotherm, indicating that this membrane formed secondary crystalline domains and failed to fuse with another membrane.

[0057] In some cases, a tip may be used to deform the first membrane. The tip may move a predetermined vertical distance after initial contact with the membrane to reach a predetermined height in the channel. In some cases, the tip may be used to fuse the two membranes where the tip brings them into contact (the first membrane is already deformed). The tip may be used to fuse the two membranes. The tip presses the first and second membranes together, for a predetermined period of time. In some cases, the tip may be used to deform the first membrane and fuse the first membrane to the second membrane in a single process or step. In some cases, the first and second membranes are vertically offset at a predetermined height. This vertical offset may determine the channel height. The tip may be used to deform and fuse the first membrane to the second membrane in a single step. The tip contacts the first membrane, moves vertically away from the first membrane toward the second membrane, and presses the first and second membranes together, for a predetermined period of time. In some cases, a single tip on the membrane may be used. 2 1 shows a schematic diagram of a fusion process by spot welding two membranes using a tip of In other cases, multiple tips may be used on the membrane, for example simultaneously.

[0058] In some cases, the tip may be moved laterally (x-y directions) and vertically (z-direction) while the membrane(s) are stationary. In some cases, the tip may be moved only vertically while the stage holding the membrane(s) is moved laterally. In some cases, the tip may move a predetermined lateral distance relative to the membrane surface, then move downward a predetermined vertical distance into the membrane and retract to a neutral vertical position (which may be its previous vertical position). This cycle may be repeated until a predetermined number of channels on the membrane(s) have deformed and / or fused. In some cases, the stage holding the membrane is moved laterally to a predetermined location below the tip, and the tip is moved downward a predetermined vertical distance into the membrane and retracted to a neutral vertical position. This cycle may be repeated until a predetermined number of channels on the membrane(s) have deformed and / or fused. The movement of the tip and / or the stage holding the membrane may be programmed and automated. The tip may move laterally in the x and / or y directions by about 100 μm, about 200 μm, about 300 μm, about 400 μm, about 500 μm, about 600 μm, about 700 μm, about 800 μm, about 900 μm, or about 1000 μm between periods. The tip may move vertically after contacting the membrane by about 100 μm, about 200 μm, about 300 μm, about 400 μm, about 500 μm, about 600 μm, about 700 μm, about 800 μm, about 900 μm, or about 1000 μm.

[0059] When using a tip to fabricate a cell containment device, there may be critical time, temperature, and pressure ranges for deformation and / or fusion of the membrane. The time during which the tip is in contact with the membrane may be referred to as the tip contact time. In some cases, the tip contact time may be about 0.1 seconds, about 0.2 seconds, about 0.3 seconds, about 0.4 seconds, about 0.5 seconds, about 0.6 seconds, about 0.7 seconds, about 0.8 seconds, about 0.9 seconds, or about 1 second. The tip contact time may be about 2 seconds, about 3 seconds, about 4 seconds, about 5 seconds, about 6 seconds, about 7 seconds, about 8 seconds, about 9 seconds, about 10 seconds, about 11 seconds, about 12 seconds, about 13 seconds, about 14 seconds, about 15 seconds, about 16 seconds, about 17 seconds, about 18 seconds, about 19 seconds, about 20 seconds, about 25 seconds, or about 30 seconds. The tip may be heated to a temperature above the critical temperature for deformation and / or fusion. The tip may be heated to a temperature about the critical temperature for deformation and / or fusing, substantially as described above. The tip may be heated to about 0°C, about 1°C, about 2°C, about 3°C, about 4°C, about 5°C, about 6°C, about 7°C, about 8°C, about 9°C, about 10°C, about 15°C, or about 20°C above the critical temperature. The tip may apply a pressure of less than 10 psi, less than 20 psi, less than 30 psi, less than 40 psi, less than 50 psi, less than 60 psi, less than 70 psi, less than 80 psi, less than 90 psi, less than 100 psi, less than 110 psi, less than 120 psi, less than 130 psi, less than 140 psi, less than 150 psi, less than 160 psi, less than 170 psi, less than 180 psi, less than 190 psi, or less than 200 psi to the membrane to effect deformation and / or fusing.

[0060] In some cases, the first membrane may or may not be sintered before fusing. In some cases, the second membrane may or may not be sintered before fusing. In one example, the first membrane may be sintered and the second membrane may not be sintered before fusing. The membranes may be sintered at various temperatures for various times. A sintered membrane may have a lower fusing temperature than an unsintered membrane of the same type. In one example, the first membrane may be sintered at 370°C for 7 minutes. Figure 37 shows DSC measurements of ePTFE membranes sintered at 370°C for 7 minutes and unsintered at 300°C. The fusing temperature of the sintered membrane was 320-325°C, lower than the 340-350°C for the unsintered ePTFE membrane. Optionally, whether or not to sinter the membrane may be important for fusing the first membrane to the second membrane. In some cases, sintering the membrane may help the membrane to deform and maintain its deformed shape. Optionally, a sintered membrane may be fused to an unsintered membrane to achieve desired properties (eg, sealing, device integrity, and / or shape).

[0061] The edges of the fused first and second membranes can be trimmed to remove excess membrane on the periphery of the cell containment device. In some cases, the trimming can be accomplished by punching. An alignment frame can be used to mount and align the cell containment device, and a peripheral punch is used to cut off excess periphery of the cell containment device.

[0062] As shown in FIG. 20, the fused portion between the first and second membranes can be cut to form the lumen of the channel. The fused portion between the first and second membranes can also be removed by laser ablation, resulting in the formation of a channel that traverses through the device. FIG. 21 shows scanning electron micrographs and images of a cell-containment device with the lumen 2752 of the fused portion 2754 cut by laser ablation and a framed cell-containment device. FIG. 22 shows a scanning electron micrograph of a cross section of a cell-containment device after a manufacturing step that includes cutting through a channel to form the lumen. The cutting can be performed by laser etching or laser ablation. The removed portion can be a portion of the fused area so as not to compromise the seal between the first and second membranes. The removed portion can be about 0%, about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, or about 99% of the fused area.

[0063] The assembled cell containment device can be part of a modular system (also referred to herein as a macrodevice). Figure 23 illustrates one or more cell containment devices 2950. Each can be filled with a cell-containing matrix, which can be assembled onto a frame 2980 to form a macrodevice. Multiple channel array devices, or cell containment devices with a matrix, can be arranged on the frame in various configurations. Each device can have a loading port 2955 for loading the matrix into the device. The loading port is designed to be small to reduce the possibility of cracking the device seal. The loading port can be used to load cells into the device. In some cases, the frame can include a flexible backing or structural support. Optionally, the channel array device can be mounted on a subframe 2981 in addition to the frame. The frame can provide flexible support for the channel array device. The frame can prevent unwanted bending of the device. The frame can have one or more flexible mechanisms to prevent buckling in sensitive device regions. The flexible mechanism 2982 can have cuts to allow the frame to flex at the cuts. The flexible mechanism allows the assembly to bend along with the tissue at the site of implantation of the assembly. The frame can have handling tabs 2956. The handling tabs may be used for surgical handling and / or implantation of the assembled device. The frame can have holes to allow for transportation.

[0064] The frame can have a flexibility mechanism that prevents buckling of the cell containment device mounted on the frame. The flexibility mechanism can include small cuts or incisions, while leaving a small portion of the frame intact. In some cases, the cuts can be in approximately the same location on the top and bottom surfaces of the frame, while leaving a small portion of the frame between the two cuts intact. In other cases, the cuts can be on one surface of the frame, while leaving a small portion of the frame intact. The cuts can be various shapes, such as generally conical, cylindrical, pyramidal, rectangular, or other shapes that remove a portion of the frame. The cuts allow the frame to bend at various angles (ranging from 0° to 90° in any given direction).

[0065] The macrodevice can have several configurations and sizes depending on the application. In some cases, the width of the macrodevice can be at least 3 cm, 4 cm, 5 cm, 6 cm, or 7 cm. In some cases, the length of the macrodevice can be at least 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, 10 cm, 11 cm, 12 cm, 13 cm, 14 cm, or 15 cm.

[0066] The cell containment device can be filled with a matrix. In some cases, the cell containment device can be filled by pressure. In other cases, the cell containment device can be filled by centrifugation. Figure 24 shows the filling of a framed (left) and unframed (right) PVDF cell containment device with a cell-containing mixture. In some cases, a fill tube can be connected to the cell containment device to fill a frameless device. In other cases, for framed cell containment devices, the frame can allow fluid channels from the fill hub to connect to a fill port on the device. Once the device is filled, it can be separated from the fill tube or fill hub and sealed. The frame can also be sealed. An adhesive or UV-curable adhesive can be used to seal the device and / or frame. The matrix can contain cells or expression systems that produce a biological product. The matrix can further contain cell culture medium. The matrix can further contain a porous biocompatible material. Leaving only a small area of ​​the cell containment device unsealed for filling reduces the risk of seal failure. After the cell containment device is filled with the matrix, the small area can be sealed. 25 shows a cell-containing device filled with matrix with cells, visualized by a hematoxylin and eosin (H&E) stained tissue section. In some cases, the cell-containing device may be filled (e.g., with cells) using the following process: First, the cells may be suspended in medium. Second, the cells may be administered into the fill port under pressure. Third, the fill port may be removed. Finally, the fill port opening may be sealed (e.g., with a UV-curable adhesive).

[0067] The assembled channel array device or its components can be treated on its surface. The surface can be treated with a material to promote angiogenesis. The coating can be VEGF or other pro-angiogenic factors or substances. The exterior surface can be treated with a material that provides antifouling properties. The device surface can be treated to reduce the likelihood of fibrosis or connective tissue formation around the device. The device material can be selected to reduce the likelihood of fibrosis. The device surface can be treated to create physical features or chemically treated to reduce fibrosis. The surface can be treated with a hydrophilic coating. Hydrophilic coatings can include polymers, polyethylene glycol, polyvinyl alcohol, polydopamine, and oactin. Figure 41 shows an example protocol for forming a hydrophilic coating on the surface of a membrane. A hydrophobic surface can be rendered hydrophilic by a hydrophilic coating prior to the coating process. Improving the hydrophilicity of the membrane surface can improve the transport of hydrophilic molecules through the membrane between the internal and external environments of the device. Figure 38 shows an ePTFE cell-containing device after hydrophilic coating treatment in water. The air bubbles indicate the water's ability to fill the interior of the device and displace air from the interior of the device.

[0068] The membrane of the cell containment device can include one or more porous materials. The membrane can include PTFE, ePTFE, PVDF, PCL, PE / PES, PP, PS, PMMA, PLGA, PLLA, or other thermoelastic materials. The materials for the membrane can be synthesized by a variety of methods. Methods for synthesizing porous materials can include expansion methods, solution casting methods, immersion precipitation and phase separation methods, electrospinning, methods that result in reticular networks, methods that result in trabecular networks, or other methods. The membrane may be a porous material that, after the manufacturing process, is capable of transporting materials through it having a molecular weight of less than about 3000 kDa, less than about 2000 kDa, less than about 1000 kDa, less than about 500 kDa, less than about 400 kDa, less than about 300 kDa, less than about 200 kDa, less than about 100 kDa, less than about 50 kDa, less than about 40 kDa, less than about 30 kDa, less than about 20 kDa, less than about 10 kDa, less than about 6 kDa, less than about 5 kDa, less than about 4 kDa, less than about 3 kDa, less than about 2 kDa, or less than about 1 kDa. The average pore size of the membrane can be about 5 nm, about 10 nm, about 15 nm, about 20 nm, about 30 nm, about 40 nm, about 50 nm, about 60 nm, about 70 nm, about 80 nm, about 90 nm, about 100 nm, about 200 nm, about 300 nm, about 400 nm, about 500 nm, about 600 nm, about 700 nm, about 800 nm, about 900 nm, about 1000 nm, about 1100 nm, about 1200 nm, about 1300 nm, about 1400 nm, about 1500 nm, about 1700 nm, about 2000 nm, or about 2500 nm.

[0069] The dimensions of the channel array can be controlled by parameters in the manufacturing steps. A mold or plate can be used to deform the first membrane into a predetermined channel array design. Temperature can be used during the deformation step to vary the channel depth. Pressure can be used during the deformation step to vary the channel depth. A combination of temperature and pressure can be used during the deformation step to vary the channel depth. The temperature and pressure during deformation can be specific to the material of the first membrane. Changes in channel dimensions can affect the three-dimensional shape of the interconnected pockets within the cell-containment device. These manufacturing parameters can be used to tailor the cell containment configuration and dimensions for the channel array device. These parameters can be used to vary the SA:V ratio of the cell containment. The SA:V ratio of the cell containment may improve vascularization within and around the device.

[0070] The device can be implanted at various sites within a subject's body. In some cases, the subject can be implanted with a device on a frame. In one example, the device can be placed by preperitoneal or retrorectus implantation. In another example, the device can be placed by intraomental implantation. In another example, the device can be placed by subcutaneous implantation. In another example, the device can be placed by suprahepatic implantation. Figure 28 shows preperitoneal, intraomental, suprahepatic, and subcutaneous implantation of a cell-containing device in a rat.

[0071] The device can be secured to the implantation site in vivo. In one example, the device can be secured using a tissue adhesive. The tissue adhesive can be fibrin, cyanoacrylate, polyethylene glycol, albumin-based adhesive, or a polymer-based adhesive. In another example, the device can be secured using platelet-rich plasma.

[0072] After in vivo implantation, blood vessels may form around the device and through the channels within the device. Figures 31 and 32 show the vasculature around and through the channels of a cell-containing device 20 and 90 days after implantation in a preperitoneal site in a rat. Figure 29 shows H&E-stained histological sections of the vasculature around and within the channels of a cell-containing device after in vivo implantation in a rat. Figure 30 shows the vascularization around low-channel-density and high-channel-density cell-containing devices after in vivo implantation. The blood vessels may have smooth muscle cells, which are commonly found in arteries. The blood vessels may have arterial characteristics. Figures 30 and 31 show that the density of channels within a channel array device can affect the level of angiogenesis. A higher channel density may increase the level of angiogenesis. A lower channel density may decrease the level of angiogenesis. The diameter of the channels within a channel array device may affect the level of vascularization and branching of the blood vessels.

[0073] The cell containment device can be designed to achieve a variety of functional goals. One goal of the cell containment device is to be able to provide at least one year of cell viability for cells within the device after implantation in vivo. In some embodiments, at least one year of cell viability is at least 4x10 8 The device may be designed to contain cells of interest. The device may be retrieved or explanted from the implantation site in the subject's body to assess post-implantation cell viability and other functional assessments. The cell-containing device may be designed to improve mass transport within the device and across the device membrane. The cell-containing device may be coated and / or implanted at a site that improves proximity to the host vascular supply. The cell-containing device may be designed to stabilize the host / device interface to allow flexibility within the device without folding in on itself. The cell-containing device may be designed to reduce tissue integration to provide stability to the device without compromising device integrity. The cell-containing device may be designed to utilize materials and coatings that result in favorable non-specific biomaterial responses.

[0074] Ultra-thin device

[0075] Although cell-containment devices including channels are primarily described herein, a cell-containment device need not necessarily include channels. For example, alternative approaches to meeting various functional goals of a cell-containment device may, in some cases, be achieved using ultrathin cell-containment devices (also referred to herein as ultrathin devices). Accordingly, various parameters, characteristics, or descriptions (e.g., coatings, materials, etc.) described with respect to a given embodiment of a cell-containment device (e.g., one including channels) may be equally applicable to other embodiments of a cell-containment device (e.g., ultrathin devices).

[0076] Ultrathin devices may have a thin overall cross-sectional thickness. Alternatively or additionally, ultrathin devices may have a thin membrane. The membrane of an ultrathin device may be a biocompatible polymer or biomaterial, such as ePTFE, PVDF, PEEK, PS, PES, PAN / PVC, nylon, polyurethane, polycarbonate, polyacrylonitrile, glass fiber, polycaprolactone, hydrogel, polyester, polyanhydride, or cellulose. The membrane may also be formed from a permanent, non-degradable material, or alternatively, a biodegradable material with a controlled degradation profile. The dimensions of an ultrathin device may result in a high SA:V ratio. A high SA:V ratio can enhance the transport of molecules into and out of the device, such as the transport of nutrients and oxygen into the device for resident cells within the device, and the transport of insulin or other secretory products out of the device. Modeled insulin diffusion out of an ultrathin device loaded with insulin-producing cells ranged from 0.4 to 10 ng / cm. 2 10 min. Ultrathin devices may not have channels running through the thickness of the device, as in the case of channel array devices. Figures 57 and 58 show schematics of a cell-filled ultrathin device (black circle) with a cross-sectional thickness of 250 μm and a macrodevice with three ultrathin devices.

[0077] The ultra-thin device may have a total cross-sectional thickness of about 250 μm. In some embodiments, the ultra-thin device may have a total cross-sectional thickness of less than 5000 μm, less than 4000 μm, less than 3000 μm, less than 2000 μm, less than 1000 μm, less than 900 μm, less than 800 μm, less than 700 μm, less than 600 μm, less than 500 μm, less than 400 μm, less than 300 μm, less than 200 μm, less than 100 μm, or less than 50 μm. In some embodiments, the ultra-thin device may have a total cross-sectional thickness of at least 1000 μm, 900 μm, 800 μm, 700 μm, 600 μm, 500 μm, 400 μm, 300 μm, 200 μm, 100 μm, 50 μm, or 10 μm.

[0078] Ultra-thin devices may have membrane thicknesses ranging from 2 μm to 25 μm, hi some embodiments, the membrane of an ultra-thin device may be less than 100 μm, less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm, less than 20 μm, less than 10 μm, less than 5 μm, or less than 1 μm.

[0079] The ultra-thin device may be designed to have an SA:V ratio appropriate for transporting nutrients and desired products through the device. In some cases, the SA:V ratio is 80 cm -1 In other cases, the SA:V ratio is about 20 cm -1 Above, about 40cm -1 Above, approximately 60cm -1 Above, about 80cm -1 More than 100cm -1 Above, about 120cm -1 Over, about 150cm -1 The maximum oxygen diffusion distance of the device may be less than 50 μm, less than 100 μm, less than 150 μm, less than 200 μm, less than 250 μm, less than 300 μm, less than 350 μm, less than 400 μm, less than 450 μm, or less than 500 μm.

[0080] The properties of the membrane of an ultra-thin device may be selected to enhance its function. One such property may be the flux selectivity of the membrane. Various membrane properties (e.g., microstructure, tortuosity, pore size, porosity, and / or thickness) may contribute to the flux selectivity. The flux selectivity may affect the molecules that can pass through the membrane. Because the microstructure affects the flux selectivity of a membrane, treatment of the membrane may affect its microstructure and its flux selectivity.

[0081] The properties of the membrane of an ultra-thin device may be selected to improve its capacity for immune protection. For example, a membrane with high flux selectivity may prevent the movement of large amounts of antibodies and complement proteins across the membrane. Also, a membrane with high flux selectivity may reduce the diffusion of nutrients through the membrane to the interior of the cell-containing device. A membrane with intermediate flux selectivity may provide favorable flux characteristics for cell survival, reduce antigen release from dead cells, and prevent some antibody movement across the membrane. A membrane with low flux selectivity may allow for high flux-facilitated nutrient exchange through the membrane, limit the transport of cells across the membrane, and prevent the transport of molecules smaller than cells. Also, a membrane with intermediate or low flux selectivity may allow the potential exchange of antibodies and may have poorer mechanical properties than a membrane with high flux selectivity.

[0082] Various types of membranes can be used for ultrathin devices. Figure 47 shows scanning electron micrographs of ePTFE membranes of different porosity thicknesses that can be used for ultrathin devices. Table 1 shows various membrane properties, such as their flux, thickness, diffusion selectivity, and insulin flux. Diffusion selectivity is defined as the ratio of antibody flux to insulin flux. A lower ratio indicates a more selective flux because insulin is a much smaller molecule than antibodies. Membrane C has lower diffusion selectivity than membranes A and B, and is more selective in allowing larger molecules (e.g., antibodies) to be transported across the membrane. [Table 1]

[0083] As shown in Figure 48, a high-flux ultrathin device containing a permselective membrane and loaded with rat islet cells was able to produce and secrete insulin in response to a 20 mM glucose stimulus. Measurements were performed by measuring the flux of C-peptide out of the ultrathin device. C-peptide (also known as connecting peptide) is a polypeptide that is cleaved from proinsulin to form the insulin molecule. Because C-peptide is present in equimolar amounts relative to insulin, the level of C-peptide indicates the level of insulin produced and secreted. Insulin transport kinetics after encapsulation in the ultrathin device was evaluated using islets harvested from Sprague-Dawley rats. Ultrathin devices loaded with encapsulated rat islet cells demonstrated a delay in insulin release from the ultrathin device of approximately 5–10 min compared to ultrathin devices loaded with free rat islets. Measurements were performed as dynamic GSIS (glucose-stimulated insulin secretion) versus time. The encapsulated islet cells were able to produce and release insulin in response to glucose stimulation. Encapsulation does not prevent the encapsulated cells from receiving and responding to glucose stimuli by producing and secreting insulin. Ultrathin devices loaded with pancreatic islet cells have diffusion kinetics that allow for switching between biphasic insulin secretion and shutoff depending on the glucose concentration in the environment. GSIS occurs when cells secrete insulin upon exposure to glucose. The amount of insulin secreted may be proportional to the level of glucose exposure. During GSIS, insulin secretion may decrease, stop, start, and increase depending on the level of glucose exposure. Some embodiments further include releasing insulin from the cells within the cell-containing device in an amount sufficient to lower the subject's blood glucose level. In some embodiments, insulin release stops when the subject's blood glucose level decreases to a normal level. In some embodiments, insulin release resumes when the cells within the cell-containing device are again exposed to the subject's elevated blood glucose level.

[0084] The choice of membrane can affect the flux kinetics of insulin from the ultrathin device and its responsiveness to glucose stimulation. Figure 49 shows static C-peptide release in ultrathin devices containing high-flux or permselective membranes and loaded with encapsulated islet cells before (LG or low glucose), during (HG), and after (LG) high glucose stimulation. Encapsulated islet cells in all three types of ultrathin membranes responded to glucose stimulation. Ultrathin devices with high-flux membranes released approximately 1.7x10 islets per device under HG conditions. 5 pM of C-peptide, whereas ultrathin devices with permselective membranes yielded approximately 5x10 pM of C-peptide per device under HG conditions. 4 The ultrathin device resulted in pM of C-peptide. In the ultrathin device, there was a delay in insulin release depending on the HG conditions. The delay in insulin release may be due to the retention of insulin within the ultrathin device and may indicate that some membranes may be sticky to insulin. Figure 50 shows dynamic GSIS in an ultrathin device with an AS1 membrane. Because AS1 is a high-flux membrane, this results in a high-flux ultrathin device that responds to a 20 mM high glucose stimulus by producing and secreting insulin and turns off insulin production and secretion when the high glucose stimulus is removed.

[0085] Ultrathin devices and cell-containing devices can be prepared by a number of processes. These processes can include membrane fabrication, membrane coating, device assembly, and sterile cell loading. Membranes can be fabricated and treated to achieve desired properties. These properties may include transport flux characteristics, mechanical properties, porosity, pore size, thickness, microstructure, or tortuosity. Fabrication processes can include membrane stretching or sintering. Membranes can be further treated using coating processes to impart various desired properties. As previously mentioned, these coatings can include hydrophilic polymers, VEGF, or other molecules to promote angiogenesis or protein transport. Membranes can then be fabricated and assembled into devices. Assembly of ultrathin devices can be performed using robotic assembly, which can be automated or semi-automated. A frame for the device can be fabricated. Optionally, one or more ultrathin devices can be assembled on the frame as a macrodevice. The ultrathin device can be sterilely loaded with cells. Sterile cell filling may be performed by a pressure filling process, centrifugation, gravity filling, open filling, or any combination thereof.

[0086] The membrane may be sintered before being fabricated into a cell-containing device. The membrane sintering process may be used to alter the membrane's porosity and flux characteristics. Sintering can increase the membrane's porosity while maintaining its pore structure. Sintering can improve the membrane's mechanical stability and insulin flux. Figure 51 shows scanning electron micrographs of unsintered and sintered membranes, demonstrating the changes in membrane microstructure. There is fusion and coalescence of the nodes and fibrils in the sintered membrane.

[0087] The sintering process is highly consistent and allows for low lot-to-lot variability. Table 2 shows the melting point temperatures of the sintered membranes (ranging from approximately 326°C to 333°C), which differ from the melting point temperature of the unsintered membranes (approximately 345°C) (measured by DSC). The sintering process resulted in a lot-to-lot variability of 0.76%, demonstrating the consistency of the sintering process. Sintering of the membrane can be used to alter the membrane porosity, which can then be used to tailor the porosity and flux characteristics of the cell-containment device. Consistency in the sintering process may provide an attractive option for influencing membrane porosity and properties in the mass production of cell-containment devices. [Table 2]

[0088] In some embodiments, the cell containment device assembled on a frame may be fabricated using a non-sintered membrane and then subjected to a post-heat cure to reduce porosity on the frame. This method of fabricating an assembly using a non-sintered membrane and post-heat cure may reduce steps, time, and / or cost in the overall manufacturing process.

[0089] In some embodiments, a cell-containing device may include at least one sintered membrane and at least one non-sintered membrane. Such asymmetric sintering of the membranes of a cell-containing device may result in a device with a controlled geometry. The use of different types of membranes within a cell-containing device may induce curvature in the device due to their different mechanical properties. The first membrane may be more flexible or ductile than the second membrane. In some embodiments, the different types of membranes within a device may be sintered and non-sintered.

[0090] Coating the membrane provides another approach to tailoring the flux characteristics of the cell-containing device. Membranes may be coated with a hydrophilic coating before being fabricated into a cell-containing device. The hydrophilic coating may wet the membrane, allow ultrafiltration that can be utilized to load the device with cells, allow diffusion, and provide a biocompatible, neutrally charged surface. Figure 52 shows the target insulin flux of 1x10 -6 mol / m 2 The hydrophilic coating process resulted in a membrane with a saturation of approximately 9% and a lot-to-lot variability of approximately 8%.

[0091] In some embodiments, the hydrophobic membrane can be coated with a hydrophilic coating. The hydrophilic coating can be biocompatible and can improve the diffusion of insulin and other molecules. In some embodiments, an uncoated hydrophobic membrane may not allow the diffusion of insulin and other molecules. In some embodiments, a nano-thin coating process may provide an appropriate level of permeability and insulin diffusion to the membrane and cell-containing device. In some embodiments, the semi-permeability of the membrane is configured to protect the cells from immune attack. In some embodiments, the semi-permeability of the membrane is configured to protect the cells from immune attack in the absence of immunosuppressive therapy.

[0092] Because ePTFE material is hydrophobic, hydrophilic polymers can be polymerized around the ePTFE microstructures to allow wetting of the membrane and reduce hydrodynamic resistance. This can facilitate ultrafiltration during the cell loading process and allow cells to be introduced into the device using lower pressures. It can also create a neutral hydrophilic surface to minimize adsorption or adhesion of host proteins and cells.

[0093] The framed, sintered membrane may be placed in 100% ethanol for 5 minutes, followed by immersion in 30% ethanol for approximately 5 minutes. The membrane can then be immersed in a coating solution consisting of 9 g APS, 27 mL HPA, and 18 mL TEGDA in 30% ethanol at room temperature for approximately 5 minutes. The polymerization reaction can be controlled using LabView software and carried out from room temperature to 70 °C, increasing at a rate of 3 °C / min. The framed, coated membrane can be removed from the coating solution, transferred to boiling 100% ethanol to remove unreacted monomer, and immersed in several changes of excess distilled water. Finally, the coated membrane is dried in a chamber using a continuous nitrogen stream.

[0094] Figure 53 shows membranes coated with three different coating processes, V1, V2, and V3, stained with H&E dye as an indication of membrane hydrophilicity. Membranes that received the V1 coating process appeared highly stained pink and appeared overcoated. Membranes that received the V2 coating process had variable levels of H&E dye staining, more intense at their edges than at the center, and appeared to have a gradient coating. Membranes that received the V3 coating process were coated with a nano-thin coating process and appeared to be uniformly coated throughout their cross-sectional thickness. Figure 54 shows the hydraulic permeabilities of the membrane, membranes that received the V1 coating process, and membranes that received the V3 coating process. The V3 coated membrane had a hydraulic permeability of approximately 1.8x10 -14 m 2 The membrane and V1 coated membrane showed a high permeability of 1x10 -15 m 2 It showed a low water permeability of less than 1000 m / s.

[0095] In some embodiments, the hydraulic permeability of the coated membrane in the ultra-thin device is at least 1×10 -16 m 2 , 1x10-15 m 2 , 1x10 -14 m 2 , or 1x10 -13 m 2 In some embodiments, the first and second membranes of the ultra-thin device may have the same hydraulic permeability. In some embodiments, the first and second membranes of the ultra-thin device may have different hydraulic permeabilities. In some embodiments, different coating processes may be used on the first and second membranes to achieve the different hydraulic permeabilities. In some embodiments, the semi-permeability of the first membrane, the second membrane, or both, is configured to protect cells from immune attack. In some embodiments, the semi-permeability of the first membrane, the second membrane, or both, is configured to protect cells from immune attack in the absence of immunosuppressive therapy.

[0096] The coating process may be designed and scaled up to coat multiple membranes or multiple cell-containing devices at one time. In some embodiments, the coating process may be scaled up to coat 40 human cell-containing devices at one time. Figure 55 shows the setup for scaling up the coating process with dry and wet coated membranes. The wettability of the coated membrane is demonstrated by the high light transmission observed by transmitted illumination of the wet coated membrane, which serves as an indication of the hydrophilicity and transparency of the coated membrane.

[0097] The frame for the cell containment device may comprise a variety of materials. In some embodiments, the frame may be a biocompatible material. As previously mentioned, the frame may hold a single cell containment device or multiple cell containment devices. The mechanical properties of the frame may be similar to the host biological tissue that will surround the device after implantation in vivo. One measure of the mechanical properties of a material is its Young's modulus. Figure 56 shows the Young's modulus of various biological and synthetic materials, as well as the target Young's modulus (composite Young's modulus) range for candidate membranes, candidate frame materials, and the overall device. The target Young's modulus for the membrane is 10 6 ~10 9 The target Young's modulus for the frame material may be in the range of 10 8 ~10 9 The target Young's modulus for the device composite (also called a macrodevice or device with frame) is in the range of 10 7 ~10 9 In some embodiments, the Young's modulus of the membrane may be in the range of 10 Pa (between the range for the device alone and the range for the frame alone). 5 Pa, 10 6 Pa, 10 7 Pa, 10 8 Pa, or 10 9 In some embodiments, the frame may have a Young's modulus of at least 10 Pa. 7 Pa, 10 8 Pa, or 10 9 In some embodiments, the Young's modulus of the device composite may be at least 10 7 Pa, 10 8 Pa, or 10 9 It may be Pa.

[0098] In some embodiments, the frame may comprise polyetheretherketone (PEEK). Figure 57 shows a simulation of the mechanical properties of a 300 μm thick PEEK frame for two cell-containment devices under a force of 150 mN. The simulation shows that the PEEK frame experiences a maximum stress of about 88 MPa (below the yield stress of about 103 MPa), a maximum strain of about 0.014, and a maximum displacement of about 4.711 mm.

[0099] Figure 58 shows an example of a PEEK frame holding a cell containment device with a fused dot at the center of the device. The frame may be microfabricated or machined using appropriate methods to achieve its target dimensions. Figure 59 shows a single frame module containing a single cell containment device with a fused dot at the center on a maximally filled frame. The filled device with a fused dot at the center on the frame demonstrates limited lateral expansion of the membrane.

[0100] Figures 89A and B show various configurations of macrodevices with multiple devices held by a macrodevice frame. In some designs, the macrodevice frame is flexible and can hold multiple devices. In some embodiments, the macrodevice frame can be a flexible, integrated frame for holding multiple devices and can have a porous structure surrounding the individual cell-containing devices.

[0101] The cell-containing device may be maximally loaded with cells, as shown in Figure 59. Figure 60 shows cell viability for at least 10 days when stored in a maximally loaded cell-containing device under standard conditions of 20% oxygen and 37°C, as evidenced by the presence of cells in H&E stained tissue sections. The cell-loaded cell-containing device may be stored under various conditions to extend the viability of the cells in the cell-containing device prior to implantation. The cell-loaded cell-containing device may be stored at various temperatures, such as 4°C, 23°C, or 37°C. In some embodiments, the storage temperature of the cell-filled cell-containing device may be at least 1° C., 2° C., 3° ​​C., 4° C., 5° C., 6° C., 7° C., 8° C., 9° C., 10° C., 11° C., 12° C., 13° C., 14° C., 15° C., 16° C., 17° C., 18° C., 19° C., 20° C., 21° C., 22° C., 23° C., 24° C., 25° C., 26° C., 27° C., 28° C., 29° C., 30° C., 31° C., 32° C., 33° C., 34° C., 35° C., 36° C., 37° C., 38° C., 39° C., or 40° C. In some embodiments, the cell-filled cell-containing device may be stored under hypoxic, normoxic, or hyperoxic conditions.

[0102] The two membranes of the cell-containing device may be fused along their surfaces into distinct dots. Various configurations of fused dot shape, diameter or distance, and density (e.g., center-to-center spacing) of the device may exist. The dots may be circular, rectangular, triangular, linear, or other shapes. The dots may have various cross-sectional distances or diameters. In some embodiments, the dot diameter may be at least 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3.0 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm, 3.8 mm, 3.9 mm, 4.0 mm, 4.5 mm, or 5.0 mm.

[0103] The device may have one fused dot or multiple fused dots. The dots may be regularly spaced. The dots may be regularly spaced in a matrix array. The dots may be irregularly or randomly spaced. In some embodiments, the dots may be spaced so that they are at least 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, or 10.0 mm center-to-center. In some embodiments, the dots may be positioned on top of each other and overlap.

[0104] The total surface area of ​​the dots may cover a portion of the surface area of ​​the membrane of the cell-containing device. The surface area of ​​the membrane of the cell-containing device covered by the dots may be a portion that does not interfere with its ability to maintain cell viability, cell function, and release of molecules from within the device. In some embodiments, the dots may cover less than 30%, 25%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, or 1% of the surface area of ​​the membrane.

[0105] The dots may provide an adhesive limiter that prevents the device membranes from bending apart. The dot density and diameter can be selected to limit the device membranes from deforming, bending, or expanding apart during filling of the device. The dot diameter and density can affect the allowable fill volume by forming a series of counters. For devices of the same dimensions, a device with a shorter dot pitch may have a higher dot density than a device with a longer dot pitch. For devices with the same dot diameter and device dimensions, a device with a shorter dot pitch may have a smaller internal volume available for filling than a device with a longer dot pitch.

[0106] The dimensions of the dots may be adjusted to control the volume and SA:V ratio within the cell-containment device. In some embodiments, the surface area of ​​the dots may be increased to decrease the volume within the cell-containment device. As a result, the increased surface area of ​​the channel may increase the SA:V ratio for the cell-containment device. In some embodiments, the surface area of ​​the dots may be decreased to increase the volume within the cell-containment device. As the surface area of ​​the dots is decreased, the decreased SA:V ratio for the cell-containment device may decrease.

[0107] The dots may be formed in a variety of patterns. The dots may be formed in a pattern that maintains the ability to load the device uniformly throughout the device. The dot pattern may be designed to control the volume and / or amount of cells that can be loaded onto the device. The dot pattern may be designed to limit swelling or bending of the device membrane during cell loading onto the device. In some embodiments, the device may have one dot. In some embodiments, the device may have multiple dots. In some embodiments, the device may have at least 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 dots.

[0108] The thickness of the device during filling can be further controlled by applying external restraints to the exterior of the device. The external restraints can be placed on the exterior of the membrane of the cell-containing device, covering most or all of the surface of the membrane. The external restraints can physically limit deformation of the membranes of the device away from each other during filling. The external restraints can be porous to aid in the release of air displaced from the interior of the device when the device is filled. The external restraints can be made further adjustable by using spacers with targeted spacing between the porous restraints. The spacers can correspond to the overall thickness of the device before filling.

[0109] The dots may be formed by various processes to fuse the membranes together at separate dots. The dots may be formed by a fusion process using the spot welding process described herein. The dots may be formed by depositing adhesive on a first membrane at a desired location relative to the dots and then contacting the first membrane with a second membrane. The adhesive dots may be stacked in multiple layers. In some embodiments, the adhesive dots are stacked in two layers. In some embodiments, the adhesive may be deposited on the membrane by an automated or semi-automated process. In some embodiments, an automated dispenser may be programmed to dispense a specific volume or weight of adhesive at a specific location. In some embodiments, the dispenser may be provided with information regarding the dimensions of the membrane and the dot pattern to guide the dispensing of the adhesive on the membrane. The dots may be formed by a combination of adhesive deposition and spot welding processes.

[0110] Many adhesives may be suitable for forming fused dots. The adhesive may be a cyanoacrylate, a urethane acrylate, a UV-cured epoxy, a heat-cured epoxy, or a two-part epoxy (one element may be grafted into the membrane (monomer) and the other applied in a molten state around it (crosslinker)). Alternatively or in combination, a solvent may be used to partially solubilize the membrane junction to form the bond.

[0111] The adhesive properties and adhesive placement pattern can be used to control dot diameter and density and the thickness of the device during filling. Adhesion can affect the rate of adhesive penetration into the membrane. The initial application may set the effective diameter of the dots. Penetration rate can be a function of adhesive viscosity. Depending on the adhesive chemistry, penetration rate may be affected by the membrane charge and degree of hydrophilization. The coating, membrane, and adhesion together shape the density of the dot pattern. Alternatively or additionally, the dot pattern can be controlled by a pico-pulse adhesive dispenser that regulates these parameters over time, allowing the dispenser to dispense non-linearly.

[0112] In some embodiments, the adhesive has a viscosity of about 200 cP to 450 cP, hi some embodiments, the adhesive has a viscosity of at least 10 cP, 20 cP, 30 cP, 40 cP, 50 cP, 60 cP, 70 cP, 80 cP, 90 cP, 100 cP, 200 cP, 300 cP, 400 cP, 500 cP, 600 cP, 700 cP, 800 cP, 900 cP, or 1000 cP.

[0113] Cell containment devices can be scaled to various sizes while maintaining various parameters constant. For example, devices can be scaled to provide a microenvironment within a mouse implantation device equivalent to that of a human implantation device. Various parameters important to device function can be maintained constant. These parameters can be the diffusion length or SA:V ratio of a molecule of interest, such as insulin. Because device size can affect mechanical properties, devices can be designed to maintain device flexibility without folding at the target implantation site. Because the loading process is also scaled up, scaled devices can be designed to accommodate loading of devices at higher throughputs. Scaled device designs can incorporate updated fluidic channels to improve the final sealing of the device after loading. As shown in Figures 74A and B, scaled device designs can incorporate an integrated macrodevice frame for multiple devices instead of the basic flexible macrodevice frame.

[0114] Provided herein is an ePTFE cell containment device including a first membrane and a second membrane opposed to and attached to the first membrane. The first membrane may include a first surface and a second surface. The first surface may include an opposing second surface having a plurality of channels and a surface area. The first and second membranes may form an enclosed compartment within the ePTFE device that provides a volume for containing cells.

[0115] A typical PVDF channel array device may be attenuated under UV light.

[0116] Although a typical frameless ePTFE channel array device may enable ePTFE transfer, in some circumstances, the device may distort in vivo. Typical frameless ePTFE channel array devices use a stable frame and straight and angled fill tubes, respectively. An angled fill tube may improve fluid flow. Furthermore, an angled fill tube may increase dead space within the fill tube attached to the membrane. Finally, an angled fill tube may reduce the need for laser vision during fabrication. As shown, an angled fill tube is angled from the symmetrical bisection of the membrane, while a straight fill tube is flush with or parallel to the symmetrical bisection of the membrane.

[0117] Further provided herein is a method for manufacturing a cell containment device. The method may include providing a first membrane, forming a plurality of channels in the first membrane, and fusing a second membrane to the first membrane. The first membrane may include a first surface and a second surface. The second surface may be opposite the first surface. A plurality of channels may be formed in the first surface of the first membrane. The second membrane may be fusing to the second surface of the first membrane. A compartment may be formed by fusing the second surface of the first membrane to the second membrane. The compartment may be configured to contain cells between the second surface of the first membrane and the second membrane.

[0118] Forming a plurality of channels in the first surface of the first membrane is accomplished by molds 1021, 1022. The molds may include a positive mold 1021 (seen in FIG. 86A) or a negative mold 1022 (seen in FIG. 86A). The positive mold 1021 may contact the second surface of the first membrane, while the negative mold 1022 may contact the first surface of the membrane. Using the negative mold 1022 may improve the 3D thermoforming of the membrane, producing a membrane with a more optimal thickness and porosity.

[0119] The top of a typical channel array device may allow cells to be inserted into the device via an external fill tube. The bottom of a typical channel array device includes a membrane. The illustrated external fill tube may include an angled fill tube, which is angled from the symmetrical bisection of the membrane. The top of a typical channel array device may also function as a mechanical frame for support. A typical channel array device may have an internal volume of approximately 24 μl, a channel quality of approximately 50, a footprint of approximately 1×0.5 cm, 1 mm channels, and an inter-channel (CC) distance of approximately 1 mm. As shown in FIG. 87, a typical channel array device includes a frame. An insertion tube 1040 may be manually attached onto the frame. The typical channel array device shown in FIG. 87 may include a rod-shaped channel array device.

[0120] Pocket frames may allow for the incorporation of fluid channels within a channel array device. Additionally, pocket frames are easier to manufacture without the need for manually adding insertion tubes. Multiple such channel array devices may be formed at once. Multiple simultaneously formed channel array devices may be easily packed, separated, and sealed to enable autonomous and / or mechanically operated manufacturing. Pocket frames within a channel array device may be formed by selective laser sintering (SLS), injection molding, solution casting, machining, or any combination thereof. Such processes may allow for a high degree of control over the geometry and resolution of the pocket frame.

[0121] Additionally, the pocket frame may be configured to provide torsional resistance, bending resistance, or both to the channel array device through its hoop strength. Such resistance may be achieved by the pocket frame having a variable thickness, width, cross-sectional shape, or any combination thereof. Additionally, the pocket frame sealed between the first and second membranes may be configured to be airtight to prevent contamination.

[0122] Finally, as shown in Figures 106a and 106b, respectively, the pocket frame 1051 in the channel array device 1050 allows for a higher and more uniform mass flow rate than the channel array device 1050 with a fill port.

[0123] As shown in Figures 107A-B, the geometric design parameters 1070 of the channel array device are optimized for effectiveness. The geometry of the channels within the channel array device 1070 may be defined by the cell chamber height (A), fusion region (B), aperture size (C), channel diameter (D), and channel spacing (E).

[0124] The cell chamber height (A) may be measured as the maximum normal distance between the inner surface of the first membrane 1071 and the inner surface of the second membrane 1072. The cell chamber height (A) may be measured as the average value of the maximum normal distance between the inner surface of the first membrane 1071 and the inner surface of the second membrane 1072 for all channels 1073 in the channel array device 1070. In some embodiments, the cell chamber height (A) is at least about 300 μm. As shown in Table 3 below, the cell chamber height (A) may be optimized to vary the diffusion flux, foreign body response, angiogenesis, atraumatic cell loading, and volume / footprint of the device.

[0125] The fused area (B) may be measured as the total surface area where the first membrane 1071 and the second membrane 1072 are fused. The fused area (B) may alternatively be measured or correlated as the surface area of ​​the top surface of the first membrane 1071 that is generally parallel to the second membrane 1072. The fused area (B) may be optimized to alter the seal integrity, foreign body response, and vascularization of the device, as shown in Table 3 below.

[0126] In some embodiments, the device 1070 further includes an opening 1074 through the first membrane 1071 and the second membrane 1072 in the channel 1073. The opening 1074 may have an opening diameter (C). The opening diameter (C) may be measured as the average, maximum, or minimum inner diameter of the opening 1074. The opening diameter (C) may be measured as the average, maximum, or minimum opening diameter (C) of multiple openings 1074 within multiple channels 1073 in the device 1070. In some embodiments, the opening 1074 is at most 25% concentric with the channel 1073 as the channel diameter (D). As shown in Table 3 below, the opening diameter (C) may be optimized to alter the seal integrity, foreign body response, and vascularization of the device.

[0127] In some embodiments, the channel diameter (D) may be measured as the maximum, minimum, or average inner diameter of the channel 1073. In some embodiments, the channel diameter (D) may be measured as the maximum, minimum, or average normal inner diameter of the channel 1073. In some embodiments, the channel diameter (D) is measured at the narrowest point within the channel. In some embodiments, the channel has an average diameter of about 400 μm to about 3,000 μm. As shown in Table 3 below, the channel diameter (D) may be optimized to alter the diffusion flux, foreign body response, angiogenesis, atraumatic cell loading, and volume / footprint of the device.

[0128] The channel spacing (E) may be measured as the maximum, minimum, or average distance between the inner surfaces of two adjacent channels 1073. The channel spacing (E) may be measured as the maximum, minimum, or average normal distance between the inner surfaces of two adjacent channels 1073. The channel spacing (E) may be measured as the average of the maximum, minimum, or average distance between the inner surfaces of two adjacent channels 1073 for each of the plurality of channels 1073. In some embodiments, the center of each channel is separated from the center of another channel by a distance of about 75 μm to about 500 μm. As shown in Table 3 below, the channel spacing (E) may be optimized to vary the diffusion flux, atraumatic cell loading, and volume / footprint of the device.

[0129] The channel 1073 may be further characterized by its aspect ratio, as shown in Figure 89B. The aspect ratio may be calculated as the ratio between the cell chamber height (A) and the channel diameter (D). The aspect ratio may be at least about 0.5. [Table 3]

[0130] As shown in Figure 107C, the channel geometry can be designed and optimized for use. Uniform cylindricality, circularity, and perpendicularity of the channel 1073 relative to the first surface of the first membrane 1073 allows for optimal use and cell growth.

[0131] Figures 108A-B show the inner surface of a typical first membrane for a channel array. Channel spacing and sizing can increase the surface-to-volume ratio, as shown in Table 4 below. Figure 90A shows a typical channel array with a channel spacing of 50 μm, and Figure 90B shows a typical channel array with a channel spacing of 270 μm.

[0132] In some embodiments, the channel array device 1070 has at least one of a length and a width of about 0.25 cm to about 3 cm. In some embodiments, each of the plurality of channels 1073 is generally perpendicular to the first membrane. In some embodiments, the channels 1073 are arranged in a linear array. In some embodiments, the channels 1073 are arranged in a polar array. In some embodiments, the device has a channel density of about 50 channels / cm2 along its cross-section. 2 In some embodiments, the device has a surface area to volume ratio of at least about 40 cm -1 In some embodiments, the channel array device 1070 includes a compartment between the first membrane and the second membrane. The compartment may include a single continuous open space. The compartment may have a volume of about 8 uL to about 600 uL.

[0133] In some embodiments, the method of forming a channel array further includes laser ablating portions of the first and second membranes within the plurality of channels, hi some embodiments, the laser ablation removes fused portions of the first and second membranes to form openings.

[0134] In some embodiments, the openings are at most 25% concentric with respect to the channel diameter. Figure 91A (left) shows a detailed image of a typical laser-drilled channel array device. The openings are unacceptably concentric with respect to the channel by greater than about 25%. Figure 91A (right) shows a detailed image of a typical laser-drilled channel array device. The openings are less than approximately 25% concentric with respect to the channel, which is acceptable. As shown in Figure 91C, increased concentricity can improve the uniformity of the width of the fused region around each opening, increasing bond strength and sealing. Furthermore, increased concentricity increases the surface area-to-volume ratio, reducing the required size of the seal area necessary for strength and integrity. Reducing the seal surface area reduces the remaining "ledges" that stimulate FBR and create additional diffusion distance for the central vessel.

[0135] The alignment of apertures and channels from left to right across a typical array device such as that shown in Figure 91B is shown in Figure 92. A concentricity value of 0 corresponds to perfect concentricity. For example, the laser ablation parameters associated with test 894 (center) produced apertures with much higher concentricity values ​​than the ablation parameters associated with test 898 (right).

[0136] Figure 93A shows an image of a typical laser-drilled channel array device. Figure 93B shows an image of the sealing interface of a channel array device. Figures 94A-B show high and low magnification images of vascularization around an implanted channel array device. Figure 95 shows an illustration of vascular host integration according to some embodiments. In some embodiments, at least one of the first membrane and the second membrane is configured to allow vascularization of cells within the device. In some embodiments, at least one of the first membrane and the second membrane is configured to allow vascularization of cells within the device in the absence of immunosuppressive therapy.

[0137] The equilibrium O tension distribution with the venous capillaries of a typical channel at a pressure of 100 mmHg is shown in Figure 96A for channel diameters of 1, 100 μm, 1, 300 μm, and 1, 500 μm and channel edge-to-edge distances of 150 μm and 250 μm. Additionally, the equilibrium O tension distribution with the venous capillaries of a typical channel at a pressure of 45 mmHg is shown in Figure 96A for channel diameters of 1, 100 μm, 1, 300 μm, and 1, 500 μm and channel edge-to-edge distances of 150 μm and 250 μm.

[0138] In some embodiments, forming the channels using a mold includes thermoforming the channels. Figures 115A-B show top perspective and cross-sectional images, respectively, of an exemplary unsintered membrane thermoformed at 360°C for 7 minutes under 3 psi of vacuum. As shown, the thermoforming process results in formed channels without cracks or structural collapse. This thermoforming process allows for sharp bends and a large cell chamber height 1150 of approximately 558 μm, resulting in an increased surface area-to-volume ratio and sufficient space for accommodating cells. While thermoforming the exemplary membrane does not result in rupture, alternative membranes and processes may provide increased fusion strength through reduced sintering and increased malleability. Such methods and membranes may also allow for larger cell chamber heights 1150.

[0139] Figure 99A shows an array of ruptured (left) and unruptured (right) channels. As shown above, thermoforming a typical membrane at 3.5 psi and 370°C for 7 minutes results in a channel with the largest cell chamber height, as shown in 118B. As shown in Figure 100 and Table 6 below, membrane 118B allows for an excellent cell chamber height of approximately 672 μm and a cell volume of approximately 27 ul. [Table 6]

[0140] Furthermore, thermoforming at a temperature of approximately 370°C can increase the membrane's fusion delamination resistance, as shown in Figure 101. The channels in this membrane were formed using the fusion tool shown in Figure 103A at a temperature of 474°C, a fusion time of 0.05 seconds, and a Z offset of 2.625 mm.

[0141] Additionally, Figure 102A shows differential scanning calorimetry graphs for the exemplary membrane of Figure 99B with a normalized enthalpy of 23.696 J / g and an onset x of 321.25°C, and a normalized enthalpy of 23.141 J / g and an onset x of 321.14°C. Additionally, Figure 102B shows electron micrographs of the membrane with (right) and without (left) membrane sintering. Sintering the membrane may increase the stability of the cell device.

[0142] 122A and 122B show illustrations and images of an exemplary thermal fusing tool. The thermal fusing tool may include a position-based fusing tool that can be configured to provide a set number of fusing points (each point for a set fusing time). In some embodiments, the set fusing time is less than about 1 second. In some embodiments, the fusing tool 1220 fusing the first membrane at one or more points for 1-6 hours. In some embodiments, the fusing tool 1220 fusing the first membrane at one or more points for up to about 16 hours. Additionally, the temperature of the fusing head can be adjusted to alter the characteristics of the channel and the resulting fusing. In some embodiments, the set fusing temperature is between about 250°C and about 600°C. In some embodiments, the fusing tool 1220 fusing a first membrane with a fusing point contact area of ​​at least about 0.07 mm 2 In some embodiments, the fusion tool 1220 contacts the side of the first membrane opposite the thermoformed surface.

[0143] In some embodiments, the channel is formed by placing the first and second membranes in a frame 1221 and striking one or more points on the first membrane with a fusing tool 1220. In some embodiments, the frame surrounds at least a portion of the outer edges of the first and second membranes. The first and second membranes may be substantially parallel during fusing. The first and second membranes may be substantially aligned, such that all or a majority of the second membrane is covered by the first membrane. The first and second membranes may be separated by a gap distance. In some embodiments, the gap distance is about 300 μm to about 1,200 μm.

[0144] In some embodiments, striking the first membrane penetrates the first membrane, the second membrane, or both and fuses a portion of the first membrane to the second membrane. In some embodiments, at least one of the first membrane and the second membrane is substantially flat. In some embodiments, at least one of the first membrane and the second membrane comprises an unsintered flat sheet.

[0145] Optimizing the fusion dot parameters may be necessary to prevent mismatches (where the fusion is misaligned and mismatched in some areas) as shown in Figure 104. The tensile peel strength test results shown in Figure 105B (measured by a typical machine shown in Figure 105B) imply that the fusion strength is inversely proportional to the amount of non-parallelism.

[0146] While the laser-drilled apertures in the post-fusion device shown in Figures 125A-B can improve aperture concentricity, misalignment of such laser-drilling tools can lead to further discrepancies. While such errors can be fixed with adhesive, as shown in Figure 97B, incorporating load cells in the fusion probe and using robotic manufacturing and guidance equipment can improve manufacturing methods to reduce rework time, waste, and leaks. Incorporating load cells allows for accurate calibration of fusion forces independent of tool geometry. Developing optimized robot-enabled fusion parameters can increase process speed and reduce thermal contraction impact. Using a visual guidance system improves fusion concentricity relative to the thermoformed channel.

[0147] An alternative exemplary load-sensitive thermal fusing tool may include a frame configured to hold a tip, a load cell, and a membrane. The thermal fusing tool may include a position-based fusing tool that is configurable to apply a set fusing force for a set fusing time for a set number of fusing points. The load cell allows the fusing tool to fuse each point with the same force. An exemplary array device including a single row of channels formed by a thermal fusing tool is shown in FIG. 107. As shown in Figure 108, the shortest fusion time of approximately 0.05 seconds produced a fusion between the membranes with the strongest peel force (0.45 N). Because peel force is indicative of fusion strength, shorter fusion times can increase device stability and lifespan. A complete device formed with a thermal fusion tool at a fusion temperature of 800°F, one hit per location, and a fusion force of approximately 6 lbs is shown in Figure 109. The round, uniform shape of the channels, as well as the peel force stress-strain curve for the device shown in Figure 110, confirm the high fusion strength of approximately 0.45 N.

[0148] A typical channel array device with channels formed with 2, 4, 6, and 8 fusion hits is shown in Figure 111. As shown in Figure 112, 8 fusion hits created the strongest fusion, while 4 fusion hits created the strongest fusion while leaving the channel intact.

[0149] Figure 113 shows a bar graph depicting fusion strength / peel force (N) versus fusion force for a typical channel array device with a first deformed membrane and a second flat membrane at a fusion temperature of 800°F, a fusion time of 0.05 seconds, and one fusion strike. While fusion strike forces of 6 and 12 pounds yielded devices with higher peel forces of approximately 0.4 N and 0.36 N, respectively, no observable relationship was observed between the two variables. Higher fusion strike forces may not be ideal due to the associated degradation of the fusion tool tip and membrane frame. This correlation is confirmed in Figures 138A-B, which show that a typical array channel device containing a membrane formed with a fusion force of 8 pounds exhibited membrane tears, wrinkles, and rectangular or double channels. Therefore, fusion forces less than 8 pounds for typical membranes are considered.

[0150] Figure 115 shows that when the channels of a device are formed with four fusion hits and a fusion force of 6 lbs, the resulting device is stronger (0.65 N) than when the channels of a device are formed with four fusion hits and a fusion force of 3 lbs (0.47 N). Both devices were formed at a fusion temperature of 800°F and a fusion time of 0.05 seconds. Additionally, Figure 116 shows that the devices formed at a fusion temperature of 800°F and a fusion time of 0.05 seconds, with the four hits and 6 lbs (~0.65) and the two hits and 8 lbs (~0.7 N) being stronger than typical devices formed with one or two hits and a 6 lbs (~0.47 N).

[0151] Figure 117A shows an image of a typical array device with a 3x3 channel array formed simultaneously. Each channel of the multiple channels is dotted once before one channel is dotted a second time. As shown in Figure 117A, a typical device is formed with a greater peel strength (0.9 N) by dotting each channel simultaneously than a device fused by dotting each channel twice consecutively before dotting another channel (0.75 N).

[0152] A comparison of peel forces for typical fused membranes is shown in Figure 118 and Table 7 below. Membrane A was formed with a load cell fusion tool using two strikes of 8 pounds of force, Membrane B was formed with a load cell fusion tool using four strikes of 6 pounds of force, and Membrane C was formed with a non-load enabled cell fusion tool. [Table 7]

[0153] Membranes A and C are shown in Figure 119. The membranes exhibit uniform, even fusion. For Membrane A, no significant difference in measured fusion strength was observed across the range of applied fusion forces. For Membrane B, fusion forces below 8 lbs produced the strongest membrane with minimal tearing, wrinkling, and drag. For Membrane C, the highest fusion strength was measured at 6 lbs. Figure 121 further compares Membranes A and C. Membrane C clearly exhibits a more uniform and higher peel force.

[0154] Figure 120 shows low- and high-resolution microscope images of a typical membrane section fused at 800°F, a fusion time of 0.05 seconds, and a fusion force of 6 lbs with four fusion hits. These images show that the typical membrane has a fusion strength of approximately 1.38 N, which is equal to the total strength of the unfused membrane.

[0155] Figure 121 shows a detailed image of the fused channels in the membrane with a seal size of approximately 170 + / - 8 um. Figure 122A shows the high concentricity of the laser ablated and fused regions. Finally, Figure 148 shows the fusion / peel forces (N) for a typical pre-laser channel array device formed using a non-load cell enabled (Generation 1) and load cell enabled (Generation 2) fusion tool. A typical membrane formed from the membrane using the load cell enabled fusion tool exhibits a significantly higher peel force (1.52 N).

[0156] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0157] As used herein, the singular forms "a," "an," and "the" include plural references unless the context clearly indicates otherwise. All references to "or" herein are intended to include "and / or" unless specifically stated otherwise.

[0158] As used herein, the term "about" refers to an amount to the nearest 10%, 5%, or 1% (including increments therein) of the recited amount.

[0159] As used herein, the term "substantially perpendicular" refers to a relationship between two or more surfaces that are within 1 degree, 2 degrees, 3 degrees, 4 degrees, 5 degrees, 6 degrees, 7 degrees, 8 degrees, 9 degrees, 10 degrees, or increments therein, of perpendicular.

[0160] As used herein, the term "substantially parallel" refers to a relationship between two or more surfaces that are within 1 degree, 2 degrees, 3 degrees, 4 degrees, 5 degrees, 6 degrees, 7 degrees, 8 degrees, 9 degrees, 10 degrees, or increments therein, of parallelism.

[0161] As used herein, the phrases "at least one," "one or more," and "and / or" are open-ended expressions, both conjunctive and disjunctive when used. For example, the expressions "at least one of A, B, and C," "at least one of A, B, or C," "one or more of A, B, and C," "one or more of A, B, or C," and "A, B, and / or C" mean A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B, and C together, respectively.

[0162] While preferred embodiments of the present disclosure have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Many variations, changes, and substitutions will occur to those skilled in the art without departing from the present disclosure. It will be appreciated that various alternatives to the embodiments of the present disclosure described herein may be employed in practicing the present disclosure. The scope of the present disclosure is defined by the following claims, and it is intended to cover methods and structures within the scope of these claims and their equivalents. [Example]

[0163] The present disclosure is further limited by the following non-limiting examples.

[0164] Example 1 Hexagonal channel array device for evaluation in small animals This example describes the configuration of a hexagonal channel array device for evaluation in small animals. Renderings of hexagonal channel array devices of various sizes are shown in Figure 6. The channel array device designed for testing in rats is an elongated hexagonal shape, measuring 1.9 cm x 0.8 cm. The rat device has 93 channels and an SA:V ratio of 82 cm. -1 The safety volume is 97% and can hold a volume of 43 μl. The channel array device designed for testing in mice is hexagonal in shape and measures 0.64 cm x 0.55 cm. The mouse device has 19 channels and an SA:V ratio of 82 cm. -1 The device has a safety volume of 95% and can hold a volume of 10 μl. The mid device is 1.4 cm x 0.55 cm, has 49 channels, and has a SA:V ratio of 83 cm. -1 At this value, the safety volume is 96% and can hold a volume of 24 μl. The size of the device can be scaled while keeping the SA:V ratio constant.

[0165] Example 2 Ultrastructural analysis of PVDF membranes after deformation steps This example describes the ultrastructural analysis of PVDF membranes after a deformation step. The PVDF membranes were subjected to a deformation step under combinations of pressure and temperature. The combinations were 65 psi and 135°C, 65 psi and 150°C, 65 psi and 165°C, 100 psi and 135°C, 100 psi and 150°C, 100 psi and 165°C, 140 psi and 135°C, 140 psi and 150°C, and 140 psi and 165°C. Figures 12 and 16 show scanning electron micrographs of cross-sections of PVDF membranes after the deformation step. Figure 17 shows the measured channel depth or characteristic depth (μm) for cell-containing devices subjected to the deformation step under different pressure and temperature conditions. The PVDF membranes exhibited different channel depths depending on the temperature and pressure conditions, with deeper channels generally observed at a higher temperature of 165°C. The channel dimensions can be controlled by the temperature and pressure conditions. Control of channel dimensions is important as it determines the SA:V ratio of the cell-containing device.

[0166] Example 3 Analysis of PVDF cell-containing devices after the fusion step This example describes the analysis of a PVDF cell-containment device after a fusion step. A first PVDF membrane was subjected to a deformation step at 65 psi and 135°C, 65 psi and 150°C, 65 psi and 165°C, 100 psi and 135°C, 100 psi and 150°C, 100 psi and 165°C, 140 psi and 135°C, 140 psi and 150°C, or 140 psi and 165°C. The deformed membrane was then fused to a second PVDF membrane at 225°C. Figure 13 shows a scanning electron micrograph of a cross-section of a PVDF cell-containment device after undergoing a fusion step. The first membrane was deformed at 65 psi and 165°C, 100 psi and 150°C, 140 psi and 135°C, and 140 psi and 150°C and fused to the second membrane. The first membrane deformed outside these temperature and pressure parameters was poorly fused, and the seam between the first and second membranes was clearly visible in scanning electron micrographs.

[0167] Figure 19 shows a scanning electron micrograph of a cross section of a poorly fused cell-containing device. The deformation steps were performed at various pressures and temperatures. Heat flow measurements taken by DSC on a membrane deformed at 165°C and 140 psi showed a secondary peak at approximately 175°C, indicating crystalline rearrangement in this deformed membrane. Heat flow measurements on a membrane deformed at 150°C and 100 psi that was successfully fused to a second membrane did not show a secondary peak.

[0168] Example 4 DSC analysis of fusion and non-fusion conditions This example describes DSC analysis of fusion and non-fusion conditions. A first PVDF membrane was subjected to a deformation step at 100 psi and 160°C or 100 psi and 173°C, followed by quench cooling. Figure 20 shows that the heat flow measurements for the membrane deformed at 100 psi and 160°C had a small shoulder peak and were similar to the baseline PVDF membrane, indicating that this membrane preserved its crystalline alignment and fused with the second membrane. The heat flow measurements for the membrane deformed at 100 psi and 173°C had a secondary peak, indicating that this membrane formed crystalline regions and did not fuse with the second membrane.

[0169] Example 5 Surface profile of the cell containment device In this example, we describe the surface profile of a cell-containment device. Figure 18 shows the surface inferometry of a cell-containment device that had a smooth surface with uniform geometry within its channel array. The active region had a smooth porous surface, while the fusion region had a flat surface.

[0170] Example 6 Ultrastructural analysis of ePTFE after deformation and fusion steps This example describes the ultrastructural analysis of ePTFE membranes after deformation and fusion steps. The ePTFE membranes were subjected to deformation steps at 30 psi and 340°C, 4 psi and 360°C, or 6 psi and 360°C. Figure 19 shows scanning electron micrographs of the ePTFE membranes after the deformation steps. The ePTFE membranes were able to form channels. Generally, increased deformation and decreased node formation were observed with increasing temperature. Figure 20 shows fused ePTFE membranes that underwent deformation steps at 6 psi and 360°C and a fusion step at 370°C for 5 minutes. ePTFE membranes require different temperature and pressure ranges for the deformation and fusion steps compared to PVDF membranes. The fabrication steps described here may be successfully applied to membranes of different materials to form cell containment devices.

[0171] Example 7 In vivo implantation of cell containment devices into rats This example describes the in vivo implantation of cell-containing devices into rats. These devices had similar channel diameters of approximately 350 μm but different channel spacings. The low-density devices had channel spacings of approximately 500 μm, while the high-density devices had channel spacings of approximately 200 μm. As shown in Figure 28, cell-containing devices with high and low channel densities were implanted in vivo in normal rats at various locations (preperitoneal, intraomental, suprahepatic, and subcutaneous implantation). Figure 29 shows angiogenesis around the cell-containing device after preperitoneal implantation. Microvessels were observed in each channel within the device. H&E histology of the vasculature showed the presence of smooth muscle cells, which were found in arteries. Figure 37 shows the additional angiogenesis and additional branching observed in the high-channel-density device compared to the low-channel-density device. Figure 32 shows the blood vessel and branch counts per device for the low-channel-density and high-channel-density devices. The high-channel-density device had approximately 1,000 blood vessels per device compared to approximately 500 blood vessels per device for the low-channel-density device. Additionally, the high channel density devices had significantly more branches, approximately 500 branches per device, compared to approximately 300 branches per device for the low channel density devices. The higher the channel density of the device, the more vascularization there was around the device. The benefit of increased vascularization seen with higher channel devices may need to be balanced with the integrity of the device as more channels are added to the device. Channel density may affect the level of vascularization around the cell-containing device.

[0172] The cell-containing devices were loaded with cells in preparation for implantation in vivo. Figure 42 shows H&E stained tissue sections of various cell-containing devices with the continuous interior space completely filled with cells. A device (top) formed with a 20 μm thick ePTFE membrane 5310 was loaded with cells 5320 throughout its single continuous interior space. This device had a modeled insulin diffusion rate of approximately 11 ng / cm over 10 minutes. 2As shown at the bottom, a device formed using a 125 μm thick PVDF membrane 5330 was loaded with cells 5320 throughout its single continuous interior space. This device exhibited a modeled insulin diffusion rate of approximately 6 ng / cm over 10 min. 2 Figure 43 shows an image of an ePTFE cell containment device filled to its maximum capacity with cells. In the top panel, an H&E-stained histological section shows a single, continuous interior space of the device filled with cells throughout the entire device. In the bottom left, a close-up image shows a microstructure containing cells within a single pocket of the interior space, approximately 150 μm high and 400 μm wide. In the bottom right, an optical microscope photograph of the ePTFE cell containment device at 5x magnification is shown, showing the continuous filling of the interior space of the fabricated cell containment device with channels. This demonstrates that the entire interior space of the cell containment device can be filled with cells.

[0173] The cell-containing device was implanted in vivo in a rat for extended periods, and the cells within the cell-containing device survived during the extended in vivo implantation. Figures 26 and 27 show the vasculature around and through the channels of the cell-containing device 20 days (Figure 26) and 90 days (Figure 27) after implantation in a preperitoneal site in a nude rat. Figure 44 shows an H&E-stained histological section of a PVDF cell-containing device 5510 with cells 5520 90 days after in vivo implantation in a preperitoneal site in a rat. The SC islet cells 5520 within the device 5510 implanted in the preperitoneal site had a high cell content at 90 days, and angiogenesis 5530 was visible around and through the channels of the device. The host tissue formed new tissue around and through the channels of the device. Figure 45 shows H&E-stained histological sections of a PVDF cell-containing device 5610 loaded with SC islet cells 5620 90 days after implantation in subcutaneous and preperitoneal sites in a nude rat capable of a foreign body reaction. The SC islet cells 5620 in the device 5610 implanted in both the subcutaneous and preperitoneal sites had high cell content at 90 days, indicating that the SC islet cells persisted within the device at both implantation sites for 90 days. Vascularization 5630 was observed around and through the device channels in both subcutaneous and preperitoneal sites. Some of the vascularization appeared to have arteriole-like features and defined vascular walls that were several cell layers thick. The exterior of the device appeared to integrate with the host tissue at both implantation sites. Although fibrosis was denser around the device in the subcutaneous site, there was no apparent effect on cell survival within the device (top and bottom left). Host tissue was also present throughout the device channels, providing support for the vascular tissue and mechanical stability to the device. This demonstrates that the cell-containing device can be transplanted at multiple implantation sites, maintain high cell viability within the device over time, and allow vascularization and new tissue formation around and through the device.

[0174] Example 8 Cluster Size Impact on Design This example illustrates how cluster size can influence design. Cluster size refers to the size of the cell aggregates packed into the device.

[0175] Example 9 Deformation conditions of ePTFE membrane This example demonstrates the effect of deformation conditions on ePTFE membranes. Figure 41 shows cross-sectional images of an ePTFE cell containment device formed by thermal deformation at 360°C and 6 psi (as formed, top) and subsequently hard-cast with resin (bottom). The as-formed ePTFE membrane did not appear to retain its channel shape and did not appear to have more fibril structures than nodes. The ePTFE membrane hard-cast with resin appeared to retain its channel shape after the deformation step.

[0176] Example 10 T-peel test of two flat ePTFE membranes This example describes the T-peel test of sintered and unsintered ePTFE membranes to test the bond strength of fused ePTFE membranes. Figure 43 shows the fracture load (N) from the ASTM D882-08 standard for thin-film tensile testing of two flat ePTFE membranes fused at different temperatures for different lengths of time (1, 5, and 15 seconds). The ePTFE membranes were either sintered at 370°C for 7 minutes (AS) or unsintered (AU) before fusing. The sintered ePTFE membranes had a fusing temperature of approximately 320°C to 325°C, while the unsintered ePTFE membranes had a fusing temperature of approximately 340°C to 350°C (measured by DSC). The two flat ePTFE membranes were fused together for 1, 5, or 15 seconds at various temperatures ranging from 302°C to 427°C. The fracture or failure load (N) was recorded after undergoing the ASTM D882-08 standard. Generally, fusions between sintered-to-sintered membranes (AS / AS) had the lowest failure loads (range of near 0 N to approximately 0.3 N) compared to unsintered-to-unsintered membranes (AU / AU) (range of near 0 N to approximately 1 N) or unsintered-to-sintered membranes (AU / AS) (range of approximately 0.2 N to 0.7 N). Generally, fusions between AU / AU membranes had higher failure loads. Generally, failure loads increased with increasing fusion temperature. Generally, having at least one unsintered membrane resulted in higher failure loads.

[0177] Example 11 T-peel testing of ePTFE devices This example describes T-peel testing of ePTFE devices. Figure 38 shows the tool used for ASTM D882-08 standard for thin film tensile testing. This tool was used to test fused, cell-containing ePTFE devices. The tested device is shown at failure. The graph shows the stress-strain curve of the ePTFE device. One membrane was sintered and deformed, while the second membrane was flat and unsintered, and they were fused at 474°C for 0.05 seconds. The ePTFE device reached a failure strain of greater than 60%, a load of approximately 0.4 N. This was approximately 78% of the load of a fused, flat membrane with a larger fused area. The stress-strain curve indicated that the fusion site fused and remained fused, even at high tensile strains.

[0178] Example 12 Burst pressure of ePTFE devices This example describes measuring the burst pressure of a cell containment device. To test the seal strength of the device, the device was filled with water at 1 psi per 10 seconds and the pressure at failure, or burst pressure, was measured. Figure 39 shows an ePTFE cell containment device without a filled frame for burst pressure testing and a graph of the fill pressure (psi) at failure for the ePTFE cell containment device (eCAD) prototype. For the PVDF prototype, the burst pressure at failure was approximately 10 psi. For the ePTFE prototype, the burst pressure at failure was approximately 11 psi. This burst pressure is much higher than the maximum fill pressure of approximately 2 psi that the device can be exposed to under typical filling conditions.

[0179] Example 13 Cell Containment Device Prototype In this example, a prototype of a cell containment device is described. Figure 14 shows a rendering of a cell containment device with a scalloped perimeter and varying channel dimensions to achieve different SA:V ratios. As shown in Figure 14, the cell containment device is characterized by overall height 1801, internal height 1802, membrane thickness 1803, internal spacing 1804, internal diameter 1805, through-hole internal diameter 1806, and through-hole spacing 1807.

[0180] In some embodiments, total height 1801 is about 400 μm to about 1,600 μm. In some embodiments, total height 1801 is at least about 400 μm. In some embodiments, total height 1801 is at most about 1,600 μm. In some embodiments, total height 1801 is about 400 μm to about 600 μm, about 400 μm to about 850 μm, about 400 μm to about 1,000 μm, about 400 μm to about 1,200 μm, about 400 μm to about 1,400 μm, about 400 μm to about 1,600 μm, about 600 μm to about 850 μm, about 600 μm to about 1,000 μm, about 600 μm to about 1,200 μm, about 600 μm to about 1,400 μm, about 600 μm to about 1, 600 μm, about 850 μm to about 1,000 μm, about 850 μm to about 1,200 μm, about 850 μm to about 1,400 μm, about 850 μm to about 1,600 μm, about 1,000 μm to about 1,200 μm, about 1,000 μm to about 1,400 μm, about 1,000 μm to about 1,600 μm, about 1,200 μm to about 1,400 μm, about 1,200 μm to about 1,600 μm, or about 1,400 μm to about 1,600 μm. In some embodiments, the overall height 1801 is about 400 μm, about 600 μm, about 850 μm, about 1,000 μm, about 1,200 μm, about 1,400 μm, or about 1,600 μm. In some embodiments, the internal height 1802 is about 300 μm to about 1,200 μm. In some embodiments, the internal height 1802 is at least about 300 μm. In some embodiments, the internal height 1802 is at most about 1,200 μm. In some embodiments, the interior height 1802 is between about 300 μm and about 400 μm, between about 300 μm and about 650 μm, between about 300 μm and about 800 μm, between about 300 μm and about 1,000 μm, between about 300 μm and about 1,200 μm, between about 400 μm and about 650 μm, between about 400 μm and about 800 μm, between about 400 μm and about 1,000 μm, between about 400 μm and about 1,200 μm, between about 650 μm and about 800 μm, between about 650 μm and about 1,000 μm, between about 650 μm and about 1,200 μm, between about 800 μm and about 1,000 μm, between about 800 μm and about 1,200 μm, or between about 1,000 μm and about 1,200 μm. In some embodiments, the interior height 1802 is about 300 μm, about 400 μm, about 650 μm, about 800 μm, about 1,000 μm, or about 1,200 μm.

[0181] In some embodiments, membrane thickness 1803 is between about 50 μm and about 250 μm. In some embodiments, membrane thickness 1803 is at least about 50 μm. In some embodiments, membrane thickness 1803 is at most about 250 μm. In some embodiments, membrane thickness 1803 is between about 50 μm and about 75 μm, between about 50 μm and about 100 μm, between about 50 μm and about 125 μm, between about 50 μm and about 150 μm, between about 50 μm and about 175 μm, between about 50 μm and about 200 μm, between about 75 μm and about 100 μm, between about 75 μm and about 125 μm, between about 75 μm and about 150 μm, between about 75 μm and about 17 ... In some embodiments, the membrane thickness 1803 is about 50 μm, about 75 μm, about 100 μm, about 125 μm, about 150 μm, about 175 μm, about 200 μm, or about 250 μm.

[0182] In some embodiments, internal spacing 1804 is between about 40 μm and about 500 μm. In some embodiments, internal spacing 1804 is at least about 40 μm. In some embodiments, internal spacing 1804 is at most about 500 μm. In some embodiments, internal spacing 1804 is between about 40 μm and about 60 μm, between about 40 μm and about 80 μm, between about 40 μm and about 100 μm, between about 40 μm and about 150 μm, between about 40 μm and about 200 μm, between about 40 μm and about 270 μm, between about 40 μm and about 350 μm, between about 40 μm and about 400 μm, between about 40 μm and about 500 μm, between about 60 μm and about 80 μm, between about 60 μm and about 1 00μm, about 60μm to about 150μm, about 60μm to about 200μm, about 60μm to about 270μm, about 60μm to about 350μm, about 60μm to about 400μm, about 60μm to about 50 0μm, about 80μm to about 100μm, about 80μm to about 150μm, about 80μm to about 200μm, about 80μm to about 270μm, about 80μm to about 350μm, about 80μm to about 400 μm, approximately 80 μm to approximately 500 μm, approximately 100 μm to approximately 150 μm, approximately 100 μm to approximately 200 μm, approximately 100 μm to approximately 270 μm, approximately 100 μm to approximately 350 μm, approximately 100 μm Approximately 400μm, approximately 100μm to approximately 500μm, approximately 150μm to approximately 200μm, approximately 150μm to approximately 270μm, approximately 150μm to approximately 350μm, approximately 150μm to approximately 400μm, approximately 1 In some embodiments, the internal spacing 1804 is about 40 μm, about 60 μm, about 80 μm, about 100 μm, about 150 μm, about 200 μm, about 270 μm, about 350 μm, about 400 μm, about 500 μm, about 400 μm, about 500 μm, about 60 μm, about 80 μm, about 100 μm, about 150 μm, about 200 μm, about 270 μm, about 350 μm, about 400 μm, or about 500 μm.

[0183] In some embodiments, inner diameter 1805 is about 300 μm to about 1,600 μm. In some embodiments, inner diameter 1805 is at least about 300 μm. In some embodiments, inner diameter 1805 is at most about 1,600 μm. In some embodiments, inner diameter 1805 is about 300 μm to about 500 μm, about 300 μm to about 700 μm, about 300 μm to about 900 μm, about 300 μm to about 1,100 μm, about 300 μm to about 1,300 μm, about 300 μm to about 1,600 μm, about 500 μm to about 700 μm, about 500 μm to about 900 μm, about 500 μm to about 1,100 μm, about 500 μm to about 1,300 μm, or about 500 μm to about In some embodiments, inner diameter 1805 is about 300 μm, about 500 μm, about 700 μm, about 900 μm, about 1,100 μm, about 1,300 μm, about 1,600 μm, about 700 μm to about 900 μm, about 700 μm to about 1,100 μm, about 700 μm to about 1,300 μm, about 700 μm to about 1,600 μm, about 900 μm to about 1,100 μm, about 900 μm to about 1,300 μm, about 900 μm to about 1,600 μm, about 1,100 μm to about 1,300 μm, about 1,100 μm to about 1,600 μm, or about 1,300 μm to about 1,600 μm.

[0184] In some embodiments, through-hole inner diameter 1806 is between about 100 μm and about 600 μm. In some embodiments, through-hole inner diameter 1806 is at least about 100 μm. In some embodiments, through-hole inner diameter 1806 is at most about 600 μm. In some embodiments, through-hole inner diameter 1806 is about 100 μm to about 200 μm, about 100 μm to about 300 μm, about 100 μm to about 400 μm, about 100 μm to about 500 μm, about 100 μm to about 600 μm, about 200 μm to about 300 μm, about 200 μm to about 400 μm, about 200 μm to about 500 μm, about 200 μm to about 600 μm, about 300 μm to about 400 μm, about 300 μm to about 500 μm, about 300 μm to about 600 μm, about 400 μm to about 500 μm, about 400 μm to about 600 μm, or about 500 μm to about 600 μm. In some embodiments, the through-hole inner diameter 1806 is about 100 μm, about 200 μm, about 300 μm, about 400 μm, about 500 μm, or about 600 μm.

[0185] In some embodiments, through-hole spacing 1807 is between about 100 μm and about 400 μm. In some embodiments, through-hole spacing 1807 is at least about 100 μm. In some embodiments, through-hole spacing 1807 is at most about 400 μm. In some embodiments, through-hole spacing 1807 is between about 100 μm and about 200 μm, between about 100 μm and about 300 μm, between about 100 μm and about 400 μm, between about 200 μm and about 300 μm, between about 200 μm and about 400 μm, or between about 300 μm and about 400 μm. In some embodiments, through-hole spacing 1807 is about 100 μm, about 200 μm, about 300 μm, or about 400 μm.

[0186] In one example, the channels 1810 of the device may have an inner diameter 1805 of 800 μm, an internal height 1802 of 650 μm, and an inner through-hole diameter 1806 of 300 μm for the through-holes 1820. The device may have an overall height 1801 of 850 μm, a 100 μm membrane thickness 1803, and an internal spacing 1804 between the channels 1810 of 270 μm. The device has an SA:V ratio of 77 cm -1In another example, the channels 1810 of the device may have an inner diameter 1805 of 650 μm, an internal height 1802 of 650 μm, and the through-holes 1820 may have an inner through-hole diameter of 400 μm. The device may have an overall height 1801 of 850 μm, a 100 μm membrane thickness 1803, and an internal spacing 1804 between the channels 1810 of 80 μm. The device may have an SA:V ratio of 138 cm -1 The dimensions and spacing of the channels 1810 may be adjusted to achieve different SA:V ratios. The device may have a through-hole spacing 1807 of about 200 μm.

[0187] Example 14 Human Device Prototype This example describes a prototype cell containment device assembled on a frame for human use. Figure 40 shows three prototype cell containment devices assembled on a frame for human use. The cell containment devices may be hexagonal in shape. The frame may have dimensions of approximately 26.9mm x 75.6mm, or may be oval in shape with perforations in the spaces between the cell containment devices. The cell containment devices may be approximately 850µm thick and 20cm long. 2 The assembled device may hold approximately 400 million cells and have a cell mass volume of approximately 350 μL. These cells may be capable of forming insulin.

[0188] Example 15 Membrane surface modification This example describes a process for modifying a membrane surface. Membranes can be treated to impart hydrophilic properties to membranes with hydrophobic surfaces. The membrane surface can also be modified by crosslinking a polymer with hydrophilic properties. The polymer can also be biocompatible, forming a biocompatible coating on the membrane. In one example, hydroxypropyl acrylate (HPA) can be crosslinked on the membrane with tetra(ethylene glycol) diacrylate (TEGDA) in a thermally initiated polymerization process using ammonium persulfate (APS) initiator. Figure 41 shows an example protocol for forming a hydrophilic coating on the membrane surface. An ePTFE device was immersed in 100% ethanol, followed by 30% ethanol for 3 minutes. The device was immersed in 3% HPA, 2% TEGDA, and 1% APS in 30% ethanol for 5 minutes and heated from room temperature to 80°C. The device was then boiled in 100% ethanol for 5 minutes, immersed in Milli-Q water or ultrapure water for 30 minutes, and dried. Figure 38 shows the ePTFE cell containment device after hydrophilic coating treatment and immersion in water, and Figure 41 shows an electron microscope image of the ePTFE device after surface modification.

[0189] Example 16 Device dot diameter and density This example describes the dot diameter and density (e.g., center-to-center spacing) of the device. The adhesive dots were stacked in two layers. The device was manually flipped over to form a pattern of adhesive dots that served to limit the device thickness during cell loading. A pattern of 37 dots (each dot approximately 1.25 mm in diameter with 3.3 mm center-to-center spacing) was deposited in two successive layers. The pattern was created on the membrane by first applying adhesive in a 0.05-second application and curing each dot separately for 1 second. A smaller second layer was applied over the first pattern with a 0.03-second dispensing time and left uncured. Peripheral adhesive was then placed as described herein, and the membrane was placed on top of the uncured adhesive using machine vision. After a 1-second penetration time, the entire assembly was cured by first curing the periphery and then sweeping the interior area to cure the dot pattern for 28 and 112 seconds, respectively. The completed device was then manually removed from the assembly platform and placed into a secondary container for post-assembly heat curing at 37°C for 2 hours.

[0190] Example 17 Dot diameter and filling parameters of the device This example describes the fill volume of devices with various dot configurations. Dot diameter and density (e.g., center-to-center spacing) can affect the allowable fill volume by forming a series of columns. Devices were prepared as described in Example 16 using various dot configurations. Devices were prepared using dot patterns. Each dot was approximately 1.25 mm in diameter and had a dot pitch of 2.6 mm, 3.3 mm, or 4.4 mm. The center of a dot was spaced from the center of its neighboring dot by the dot pitch distance. For devices of the same dimensions, a device with a shorter dot pitch may have a higher dot density than a device with a longer dot pitch. For devices with the same dot diameter and device dimensions, a device with a shorter dot pitch may have a smaller internal volume available for filling than a device with a longer dot pitch. The devices were then filled with a cell suspension either unrestricted on the exterior of the device or with an external restriction. The external restriction may prevent the device membranes from expanding outward, away from each other. Figure 2 shows how the amount of cells loaded into the device varies with the dot pitch and the presence of a restriction. As the dot pitch decreased, the amount of cells packed decreased. The cell amount was 108 x 10 in the device packed without a restriction at a dot pitch of 4.4 mm. 6 From the cells, a dot pitch of 2.6 mm was used to determine the 42 x 10 6 For devices with the same dot pitch, the amount of cells loaded into the device was reduced when loaded using an external restriction.

[0191] Example 18 Adhesive dots on the cell containment device When forming dots on the cell-containing device, the device can be manually inverted to create a pattern of adhesive dots that act to limit the device thickness during cell loading. For example, a pattern of 37 dots (each dot approximately 1.25 mm in diameter with a 3.3 mm center-to-center spacing) was deposited in two successive layers. The pattern was created on the membrane by first dispensing adhesive with a 0.05-second application time and curing each dot separately for 1 second. A smaller second layer was applied over the first pattern with a 0.03-second dispensing time and left uncured. Peripheral adhesive was then placed on the membrane, and machine vision was used to position the membrane on top of the uncured adhesive. After a 1-second break-in time, the entire assembly was cured by first curing the perimeter and then sweeping the interior area to cure the dot pattern for 28 and 112 seconds, respectively. The completed device was then manually removed from the assembly platform and placed in a secondary container for post-assembly thermal curing at 37°C for 2 hours.

[0192] Example 19 Implantation of ultra-thin devices in vivo This example describes the implantation of ultrathin cell-containing devices into the NODscid gamma (NSG) mouse model, an immunodeficient mouse model. Diabetes was induced in NGS mice. As shown in Figure 61, the blood glucose levels of the mice rose to over 400 mg / dL. After diabetes induction, ultrathin devices were implanted into the epididymal fat pads of the mice. Figure 61A shows an example of an implanted ultrathin device. These implanted ultrathin devices contain a high-flux ePTFE membrane with a hydrophilic coating and 8 million SC islet cells. After implantation of the ultrathin devices, the blood glucose levels of all test mice decreased to approximately 100 mg / dL, close to pre-diabetes induction levels, and remained so for 90 days until the ultrathin devices were removed or explanted, as shown in Figure 61. The explanted ultrathin devices were analyzed by histology. Figures 62B and 62C show a high density of cells throughout the device, including the nucleus, after 90 days of implantation in the NSG mouse model. An ultra-thin device loaded with pancreatic islet cells can be implanted into a diabetic subject to reduce and normalize the subject's blood glucose levels over the long term.

[0193] Example 20 In vivo implantation of the AS1 ultrathin device This example describes the status of cells within an ultrathin device after 30 days and 3 months of in vivo implantation in a mouse model. Figure 62 shows a low-magnification image of a histological section of a cell-loaded ultrathin device after 30 days of in vivo implantation in a mouse model. An ultrathin device was formed using an AS1 membrane and loaded with SC islet cells (designated SEM-01). Figure 63 shows a high-magnification image of the histological section. Cells were well distributed and viable throughout the device after 30 days in vivo.

[0194] Example 21 In vivo transplantation of endocrine cells in ultrathin devices This example describes the cellular phenotype of endocrine cells within an ultrathin device after three months of in vivo implantation in a mouse model. Figure 64 shows endocrine cell microaggregates prior to encapsulation and loading into a cell containment device. Figure 65 shows a stained histological image of an endocrine cell microaggregate-loaded ultrathin device after three months of in vivo implantation in a mouse. Blue stains indicate nuclei, orange-brown stains indicate the presence of C-peptide, and pink stains indicate the presence of glucagon. The orange-brown and pink stains within the microaggregates in Figure 64 indicate the presence of active endocrine cells secreting C-peptide and glucagon. The orange-brown and pink stains within the microaggregates in Figure 65 indicate that the endocrine cells within the ultrathin device remained viable and active during three months of in vivo implantation, maintaining their endocrine phenotype, secreting C-peptide and glucagon.

[0195] Example 22 Intraperitoneal glucose tolerance test using an ultra-thin device This example describes an intraperitoneal glucose tolerance test using various ultrathin device configurations. Figure 66 shows serum C-peptide and total insulin levels in mice implanted with endocrine cells or ultrathin devices loaded with endocrine cells. Test groups included subcapsularly implanted D601mcRA2 endocrine cells (Group A), ultrathin devices loaded with D601 cells and equipped with an AS1 membrane (Group B), and ultrathin devices loaded with D601 cells and equipped with a Type A ePTFE membrane (Group C). Cells or devices were implanted into mice, and an intraperitoneal glucose tolerance test was performed. Serum C-peptide levels were measured at baseline (blue) and after a 30-minute glucose stimulation (orange), along with total insulin content within the implants. All groups showed an increase in serum C-peptide levels upon glucose stimulation, indicating glucose-stimulated insulin production. Group A had serum C-peptide levels of approximately 100 pM at baseline, approximately 250 pM upon glucose stimulation, and a total insulin content of approximately 700 μg. Group B had serum C-peptide levels of approximately 100 pM at baseline, approximately 200 pM upon glucose stimulation, and a total insulin content of approximately 500 μg. Group C had serum C-peptide levels of approximately 50 pM at baseline, approximately 600 pM upon glucose stimulation, and a total insulin content of approximately 550 μg. This example shows evidence of glucose control due to increased insulin production, as measured by increased serum C-peptide levels.

[0196] Example 23 Host / ultrathin device interactions in a nude mouse model This example describes the interaction of the host with the ultrathin device after device implantation in a nude mouse model. Figure 67 shows an H&E-stained image of an ultrathin device explant containing a coated permselective membrane loaded with SC islet cells after 3 months in the preperitoneal site of a nude rat. The image demonstrates the mitigation of foreign body reaction (FBR) within the ultrathin device with a hydrophilic-coated permselective membrane due to macrophage fusion and the absence of neovascularization. The image also demonstrates the separation of host tissue from the interior of the ultrathin device and the concentration of viable cells within the device.

[0197] Example 24 Cell viability and phenotype in implanted devices loaded with SC islet cells This example demonstrates the maintenance of cell viability and phenotype after 12 weeks of implantation of an ultrathin device loaded with SC islet cells into a nude mouse model. Figure 68 shows an H&E stained image of an ultrathin device loaded with 16 million SC islet cells after 12 weeks of implantation into the preperitoneal site of a nude mouse model. The image demonstrates high levels of cell viability within the device core after 12 weeks in vivo. Figure 69 shows serum C-peptide levels over a 60-minute period in four different mice implanted with an ultrathin device loaded with SC islet cells after glucose administration into the peritoneal cavity. Serum C-peptide increased over time from approximately 30–100 pM at 0 minutes to over 1000 pM in all four mice. This indicates that the SC islet cells within the ultrathin device implanted in mice remain active and maintain their ability to produce insulin.

[0198] Example 25 Biocompatibility of ultrathin devices implanted in an immunocompetent mouse model This example describes the biocompatibility of an ultrathin device with an AS1 membrane implanted in an immunocompetent Black 6 mouse model. Blank, mouse-sized ultrathin devices with coated AS1 membranes were placed subcutaneously in Black 6 mice to assess baseline host response to the ultrathin device materials. After one month, the devices were evaluated for maintenance of device integrity and foreign body reaction (FBR) from host tissue and cells. Figures 70A and 84B show the absence of cells and FBR within the device. FBR is described as peaking within the first month (Beets, 1998). The images demonstrate that device integrity was maintained while in vivo and that the device materials and coatings are biocompatible and do not induce FBR.

[0199] Example 26 Implantation of ultrathin devices into the NSG mouse model of diabetes This example describes the implantation of an ultrathin device with an AS1 membrane and encapsulated rat islet cells into an NSG mouse model of diabetes. Ultrathin devices loaded with 400IEQ rat islet cells with an AS1 membrane were implanted into diabetic NSG mice for 90 days. Figure 71 shows H&E staining images of an ultrathin device with viable, intact rat islet cells after 90 days in vivo. Figure 72 shows blood glucose levels before and over 90 days after implantation of the ultrathin device. After inducing diabetes, animals were administered insulin pellets to control glycemia for the first 10-20 days of the experiment. After implantation of the ultrathin device (labeled "implanted"), blood glucose levels decreased from over 400 mg / dL to approximately 100 mg / dL to approximately 300 mg / dL over the 90-day period. Blood glucose levels increased after explantation of the device from the mouse. This indicates that implantation of the ultrathin device can provide long-term glucose control.

[0200] Example 27 Cell filling in ultra-thin devices Figures 87 and 88 show various configurations of ultrathin devices. The ultrathin device designed for implantation into a mouse model can be loaded with 8 million cells and has fused dots at the center of the device. The ultrathin device designed for human implantation has neither fused dots nor an array of dots and can be loaded with 133 million cells.

[0201] Example 28 Mass flow rate of ultra-thin devices with dots Figure 75A shows an ultra-thin human implant device with an array of spot welds that provides an adhesive restriction that prevents the two membranes of the device from bending apart when the device is filled. Figure 75B shows a setup using a perforated metal platen that provides an external restriction for the ultra-thin device that prevents the two membranes of the device from bending apart when the device is filled. An external porous restriction may be used when filling any cell-containing device (e.g., ultra-thin devices and ultra-thin devices with spot welds). Figure 77 shows the mass flow rate measured from filling an ultra-thin human implant device with a 3.3 mm dot pitch and with and without an external porous restriction. Mass flow rate (cm 3 The mass flow rate (measured in sccm or standard cubic centimeters per minute) was similar with and without the external porous restriction, reaching a peak of about 7.5 or 8 sccm at about 10 seconds and decreasing with time. After reaching the initial peak, the mass flow rate was slightly higher without the external porous restriction. Figure 78 shows an H&E stained image of the cell distribution throughout an ultrathin device with an adhesion restriction, similar to the device shown in Figure 75A. This demonstrates that the device with the adhesion restriction can be filled uniformly throughout the device.

[0202] Example 29 Cell loading of ultra-thin devices without or with dots This example demonstrates cell loading of ultrathin devices without and with dots. Figures 79A and 79B show two configurations of hexagonal ultrathin devices: without dots (A) and with a 3.3 mm dot array matrix throughout the device (B). Figure 80 shows the amount of cells that can be loaded into a single ultrathin device without dots, as in Figure 79A, and with a 3.3 mm dot array matrix, as in Figure 79B. The device without dots was loaded with approximately 120 million cells, while the device with the 3.3 mm dot matrix was loaded with approximately 80 million cells. This demonstrates that the dot array matrix can be used to tailor cell loading and to prevent the device membrane from expanding or bending during cell loading.

[0203] Example 30 Cell loading of ultra-thin devices with restrictions This example demonstrates cell loading of ultrathin devices with and without porous restrictions. Figures 81A and 81B show two configurations of hexagonal ultrathin devices with a 3.3 mm dot array matrix, loaded without any restrictions (A) and with porous platens spaced apart using 400 μm spacers (B). Figure 82 shows the amount of cells that can be loaded into a single ultrathin device without any restrictions, as in Figure 81A, and with porous restrictions, as in Figure 81B. The device without any restrictions could be loaded with approximately 87 million cells, while the device with porous restrictions could be loaded with approximately 80 million cells. This demonstrates that the porous restrictions can limit membrane expansion and bending during device loading. The restrictions can be further adjusted by using spacers with a target distance between the porous restrictions.

[0204] Example 31 In vivo transplantation into a minipig model This example describes a minipig implantation study of a human-sized ultrathin device. Ten minipigs were implanted with empty ultrathin devices or ultrathin devices loaded with SC islet cells (SEM-01) or porcine islet cells in preperitoneal or subcutaneous locations. Figure 83A shows an example of an ultrathin device with a 2.6 mm dot pitch in a human single-module design implanted in a minipig. Figure 83B shows the targeted preperitoneal or subcutaneous implantation site, located approximately 3 inches from the minipig's midline to avoid the costal margin. Figure 83C shows a subcutaneous incision made with Bovie electrocautery to prepare for device implantation. Figure 83D shows a preperitoneal incision made with an illuminated retractor to prepare for device implantation. The implantation site incision can be adapted for different implantation approaches. Figure 84A shows an example of subcutaneous placement of an ultrathin device. Figure 84B shows an example of preperitoneal placement of an ultrathin device. An example of a minipig two weeks after subcutaneous (SQ) and preperitoneal (PP) implantation of the ultrathin device is shown in Figure 85. Images show no macroscopic evidence of inflammation around the implantation site, and the animal showed no signs of distress or pain. The present invention provides, for example, the following items. (Item 1) 1. A cell containment device comprising: (a) a first membrane having a first surface including a plurality of channels and a plurality of second surfaces opposite the first surface; (b) a second membrane facing and attached to the plurality of second surfaces of the first membrane; The first membrane and the second membrane have a surface area to volume ratio of at least about 40 cm -1 forming an enclosed compartment of The cell containment device, wherein the enclosed compartment provides a volume for containing cells within the device. (Item 2) The device of item 1, wherein the compartment comprises a single continuous open space. Item 1. The device according to item 1, having a volume of about 8 uL to about 1,000 uL. (Item 4) Item 1. The device according to item 1, wherein at least one of the length and the width is about 0.25 cm to about 3 cm. (Item 5) Item 1. The device of item 1, having a thickness of at least about 300 μm. (Item 6) Item 2. The device of item 1, wherein the plurality of channels are substantially perpendicular to the first membrane. (Item 7) Item 1, wherein the plurality of channels are arranged in a linear array. (Item 8) Item 1, wherein the plurality of channels are arranged in a polar array. (Item 9) Item 2. The device according to item 1, wherein the plurality of channels have an average diameter of about 400 μm to about 3,000 μm. (Item 10) Item 10. The apparatus of item 9, wherein the diameter is measured at the narrowest point within the plurality of channels. (Item 11) Item 2. The device according to item 1, wherein the center of each of the plurality of channels is separated from the center of another channel by a distance of about 75 μm to about 500 μm. (Item 12) Item 10. The device of item 1, wherein the channel has a height-to-diameter ratio of at least about 0.2. (Item 13) The device has approximately 50 channels per square centimeter along its cross section. 2 Item 1. The apparatus according to item 1, (Item 14) Item 10. The device of item 1, wherein at least one of the first membrane and the second membrane comprises a plurality of nodes interconnected by a plurality of fibrils. (Item 15) Item 2. The device of item 1, wherein at least one of the first membrane and the second membrane comprises PVDF, PTFE, ePTFE, PCL, PE / PES, PP, PS, PMMA, PLGA, PLLA, or any combination thereof. (Item 16) Item 10. The device of item 1, further comprising an opening through the first membrane and the second membrane in the channel. (Item 17) Item 17. The device according to item 16, wherein the opening is concentric with the channel by at most 25% of the diameter of the channel. (Item 18) Item 10. The device of item 1, further comprising a frame configured to receive the device. (Item 19) Item 19. The device of item 18, wherein the frame is configured to receive a plurality of cell containment devices. (Item 20) Item 19. The device of item 18, wherein the frame includes a flexible mechanism configured to prevent buckling of the cell containment device. (Item 21) 2. The device of item 1, further comprising a cell population. (Item 22) 22. The device of item 21, wherein the cell population is an insulin-secreting population. (Item 23) 22. The device of item 21, wherein the cell population is stem cell-derived cells capable of glucose-stimulated insulin secretion (GSIS). (Item 24) 10. The device of claim 1, further comprising a coating comprising a hydrophilic polymer. (Item 25) Insulin diffusion coefficient is approximately 2x10-6cm 2 / s~approx. 1x10-5cm 2 Item 1. The device according to item 1, wherein (Item 26) Item 1. The device of item 1, wherein the maximum oxygen diffusion distance is less than about 150 μm. (Item 27) Item 10. The device of item 1, wherein the first membrane and the second membrane are fused with a fusion peel force of at least about 0.4 N. (Item 28) Item 10. The device of item 1, wherein at least one of the first membrane and the second membrane is semi-permeable. (Item 29) 29. The device of claim 28, wherein the semipermeability of the first membrane, the second membrane, or both is configured to protect the cells from immune attack. (Item 30) 30. The device of item 29, wherein the semipermeability of the first membrane, the second membrane, or both is configured to protect the cells from immune attack in the absence of immunosuppressive therapy. (Item 31) Item 10. The device of item 1, wherein at least one of the first membrane and the second membrane is configured to allow vascularization of the cells within the device. (Item 32) 32. The composition of claim 31, wherein at least one of the first membrane and the second membrane is configured to allow vascularization of the cells within the device in the absence of immunosuppressive therapy. (Item 33) 1. A cell containment device comprising: (a) a first membrane having a first surface including a plurality of channels and a plurality of second surfaces opposite the first surface; (b) a second membrane facing and attached to the plurality of second surfaces of the first membrane; the first membrane and the second membrane form an enclosed compartment; The cell containment device wherein the enclosed compartment provides a volume for containing 1 million to 1 billion insulin-producing cells within the device, and the membrane retains the insulin-producing cells within the device while allowing diffusion of insulin from the device. (Item 34) A composition comprising insulin-producing cells and a device containing the insulin-producing cells, wherein the device, when implanted into an individual, releases insulin while retaining the insulin-producing cells within the device, and facilitates tissue vascularization within and around the device (Item 35). 35. The composition of claim 34, wherein the individual is not administered immunosuppressive drugs during the implantation or vascularization of the device. (Item 36) 35. The composition according to item 34, comprising 1 million to 1 billion insulin-producing cells. (Item 37) 35. The composition of claim 34, wherein the device has a thickness of at least about 300 μm. (Item 38) 35. The composition of claim 34, wherein the device comprises a membrane comprising a plurality of nodes interconnected by a plurality of fibrils. (Item 39) 1. A method of manufacturing a cell containment device, comprising: (a) providing a first membrane having a first surface and an opposing second surface; (b) forming a plurality of channels in the first surface of the first membrane; (c) fusing a second membrane to the second surface of the first membrane to form a compartment for containing cells between the second surface of the first membrane and the second membrane. (Item 40) forming a plurality of channels in the first membrane; (a) heating the first membrane at a predetermined pressure and a predetermined temperature for a predetermined time; (b) forming the plurality of channels using a mold. (Item 41) Item 41. The method according to item 40, wherein fusing the second membrane to the first membrane is performed in the mold. (Item 42) Item 42. The method of item 41, wherein the mold comprises a positive mold. (Item 43) Item 42. The method of item 41, wherein the mold comprises a negative mold. (Item 44) Item 41. The method according to item 40, wherein the predetermined temperature is from about 100 degrees Celsius (C) to about 600 degrees Celsius. (Item 45) Item 41. The method of item 40, wherein the predetermined pressure is from about 2 pounds per square inch (psi) to about 140 psi. (Item 46) Item 41. The method according to Item 40, wherein the predetermined time is about 3 minutes to about 30 minutes. (Item 47) Item 41. The method of item 40, wherein the predetermined pressure is about 3.5 psi and the predetermined temperature is about 370°C. (Item 48) forming a plurality of channels in the first membrane and fusing the second membrane to the first membrane; (a) placing the first membrane and the second membrane in a frame, wherein the first membrane and the second membrane are substantially parallel, substantially aligned, and separated by a gap distance; (b) depositing one or more dots on the first membrane with a fusing tool, the fusing tool being heated to a set fusing temperature, and between each dot, the fusing tool contacting the membrane for a set fusing time. (Item 49) Item 49. The method of item 48, wherein the dotting of the first membrane penetrates the first membrane, the second membrane, or both, and fuses a portion of the first membrane to the second membrane. (Item 50) Item 49. The method of item 48, wherein the frame surrounds at least a portion of the outer edges of the first membrane and the second membrane. (Item 51) Item 49. The method according to Item 48, wherein the gap distance is about 300 μm to about 1,200 μm. (Item 52) The fusion tool has a contact area of ​​at least about 0.07 mm 2 Item 49. The method according to item 48, wherein (Item 53) 49. The method of claim 48, wherein applying one or more dots to the first membrane with a fusing tool comprises applying each of the one or more dots up to about 16 times. (Item 54) Item 54. The method of item 53, wherein applying one or more dots to the first membrane with a fusion tool comprises applying each of the one or more dots 1 to 6 times. (Item 55) Item 54. The method according to Item 53, wherein the set fusion temperature is about 250°C to about 1,600°C. (Item 56) 54. The method of claim 53, wherein the set fusion time is less than about 1 second. (Item 57) Item 39. The method of item 39, wherein at least one of the first membrane and the second membrane is substantially flat. (Item 58) Item 40. The method of item 39, further comprising embossing the first membrane before forming the plurality of channels in the first membrane. (Item 59) 40. The method of claim 39, further comprising laser ablating portions of the first membrane and the second membrane within the plurality of channels. (Item 60) Item 60. The method of item 59, wherein the laser ablation removes the fused portion of the first membrane and the second membrane to form an opening. (Item 61) Item 61. The method of item 60, wherein the opening is concentric with the channel by at most 25% of the diameter of the channel. (Item 62) 40. The method of claim 39, wherein at least one of the first membrane and the second membrane comprises PVDF, PTFE, ePTFE, PCL, PE / PES, PP, PS, PMMA, PLGA, PLLA, or any combination thereof. (Item 63) 40. The method of claim 39, further comprising coating the device with a hydrophilic polymer. (Item 64) Item 40. The method of item 39, wherein the first membrane is sintered. (Item 65) 40. The method of claim 39, wherein the second membrane is not sintered. (Item 66) 40. The method of claim 39, wherein the second membrane and the first membrane are fused with a fusing peel force of at least about 0.2 N. (Item 67) 1. A method comprising: a) contacting tissue of a diabetic or pre-diabetic subject with a device comprising a population of insulin-secreting cells, said device comprising: (i) a first membrane having a first surface including a plurality of channels and a plurality of second surfaces opposite the first surface; (ii) a second membrane facing and attached to the plurality of second surfaces of the first membrane; The first membrane and the second membrane have a surface area to volume ratio of at least about 40 cm -1 forming an enclosed compartment of the enclosed compartment provides a volume within the device for containing cells; and b) releasing insulin from the insulin-secreting cell population in response to elevated blood glucose levels in the diabetic subject, wherein the elevated glucose levels are higher than blood glucose levels in a non-diabetic subject. (Item 68) 68. The method of any one of paragraphs 67, wherein said insulin-secreting cell population releases insulin in an amount sufficient to lower blood glucose levels in said diabetic or pre-diabetic subject. (Item 69) 69. The method of claim 68, wherein releasing insulin is stopped once the blood glucose level in the diabetic subject drops to a normal level. (Item 70) 70. The method of paragraph 69, wherein releasing insulin resumes when the insulin-secreting cell population is again exposed to elevated blood glucose levels in the diabetic subject. (Item 71) 71. The method of item 70, wherein the insulin-secreting cell population is a stem cell-derived cell population. (Item 72) 72. The method of claim 71, wherein the insulin-secreting cell population is capable of glucose-stimulated insulin secretion (GSIS). (Item 73) Item 69. The method of item 68, wherein at least one of the first membrane and the second membrane is semipermeable. (Item 74) 74. The method of claim 73, wherein the semipermeability of the first membrane, the second membrane, or both is configured to protect the cells from immune attack. (Item 75) 75. The method of claim 74, wherein the semipermeability of the first membrane, the second membrane, or both is configured to protect the cells from immune attack in the absence of immunosuppressive therapy. (Item 76) Item 69. The method of item 68, wherein at least one of the first membrane and the second membrane is configured to allow vascularization of the cells within the device. (Item 77) 77. The method of claim 76, wherein at least one of the first membrane and the second membrane is configured to allow vascularization of the cells within the device in the absence of immunosuppressive therapy.

Claims

[Claim 1] The invention described in the specification.

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