Device for the distribution and reception of a heterogeneous population of pancreatic cells, process and bioreactor

Abstract

Distribution and reception device for a heterogeneous population of pancreatic cells, method and bioreactor The invention relates to a distribution and reception device for a heterogeneous population in size of pancreatic islets, comprising a matrix having a first face opposite a second face, characterized in that the matrix comprises concentric channels centered on a center O, the channels have an opening for receiving pancreatic cells, opening onto the first face, the opening extending over the entire length (L) of the channel, the opening having a width (l) taken according to section Si, the device being configured so that the widths of the opening of two adjacent channels have an equal or increasing value when moving away from the center O and that the widths of the opening of a channel closest to the center O and of a channel furthest from the center O have an increasing value when moving away from the center O.The field of implantable devices, in particular artificial pancreas. Figure for the abstract: Fig.1.

Description

Title of the invention: Device for the distribution and reception of a heterogeneous population of pancreatic cells, method and bioreactor. Technical field

[0001] The present invention relates to the field of implantable devices, in particular artificial pancreas. Its particularly advantageous application is the production of insulin for the treatment of diabetes, and especially type 1 diabetes. PRIOR TECHNOLOGY

[0002] Diabetes is a disease with a global reach, affecting both children and adults and requiring intensive lifelong therapeutic monitoring. It is estimated that there are 300,000 patients with type 1 diabetes in France and 8 million worldwide.

[0003] Diabetics must constantly monitor their blood glucose level (commonly abbreviated as GGT, which can also be referred to as blood sugar) in order to receive treatment in case of hypoglycemia (abnormally low GGT) or hyperglycemia (abnormally high GGT).

[0004] Many complications can be avoided by anticipating these critical glucose levels. Indeed, diabetes can cause heart, kidney, retinal, or nervous system disorders in the event of a significant increase or decrease in blood glucose. Furthermore, it should be noted that the costs of treating these complications represent the majority of expenses related to diabetes therapy.

[0005] It is therefore essential, from both a health and economic perspective, to find a way to maintain blood glucose levels within a normal range in individuals with diabetes. Currently, there are methods for patient-controlled blood glucose monitoring. Among these, glucose-glucose (GBG) can be measured on an as-needed basis using an electrochemical device with enzyme electrodes printed on test strips, quantifying blood glucose from a single drop of blood. These devices, commonly called point-of-care devices, allow diabetics to independently monitor their blood glucose. However, patients are required to prick their fingers several times a day to control their blood glucose and thus avoid any complications of diabetes. This monitoring is burdensome for the patient and often leads to loss of sensation in the areas of the body frequently pricked.

[0006] As an alternative, pancreatic islet transplantation is a proposed treatment for type 1 diabetes, particularly for so-called unstable diabetic patients for whom blood glucose control and monitoring are difficult to implement and cause complications.

[0007] To perform this pancreatic islet transplantation, also called islet allotransplantation, physicians typically harvest islets containing healthy pancreatic beta cells from the pancreas of a deceased organ donor. Physicians then inject the healthy islet cells into the patient through a vein carrying blood to the liver. Once attached to the patient's liver, these islets begin to produce and release insulin into the patient's body. Several injections of transplanted islet cells are often necessary to discontinue insulin use.

[0008] However, after explantation, vascularization around the transplanted islets requires a certain amount of time, during which many islets degrade due to a lack of oxygen and nutrients. Islet mortality is estimated to be between 0% and 40% of the number of transplanted islets. In addition, systemic immunosuppression must be administered to the patient to prevent rejection of the transplanted islets.

[0009] Several approaches have been proposed to limit problems related to inflammation. Some approaches include molecular and pharmacological treatments to protect pancreatic islets against immune reactions. However, these treatments remain burdensome for the patient and of limited effectiveness.

[0010] Other solutions involve encapsulating the islets in polymer matrices, isolating them from the body's internal environment. This protects the islets from attacks by the immune system. Microencapsulation approaches for islets exist. However, due to their size, microcapsules remain difficult to produce and retrieve for islet replenishment, thus hindering long-term insulin delivery.

[0011] There are also approaches to macroencapsulating islets. One of these generally involves mixing the islets with a polymer that is then solidified. However, due to their size, the diffusion of nutrients and oxygen within the macrocapsules is limited, particularly at the core of the macrocapsule. Furthermore, surface biofouling leads to isolation of the macrocapsule, further limiting the diffusion of nutrients and oxygen. Islet mortality remains too high to allow for effective insulin delivery.

[0012] A second type of macroencapsulation concerns bioreactor-type devices, which consist of confining the islets within a closed device to form, for example, an artificial pancreas. This bioreactor offers patients the prospect of eliminating insulin therapy, thus improving their quality of life. However, the effectiveness of these devices requires the development of strategies to ensure that the islets can meet their oxygen needs. Currently, two solutions are being developed in parallel worldwide: a process for oxygen synthesis within the bioreactor: This The solution is notably developed by the team of Anderson et al. [Krishnan SR, Liu C, Bochenek MA, Bose S, Khatib N, Walters B, O'Keeffe L, Facklam A, Langer R, Anderson DG (2023) A wireless, battery-free device enables oxygen generation and immune protection of therapeutic xenotransplants in vivo. Proc Natl Acad Sci 120:e2311707120] which included a battery allowing the hydrolysis of water to extract oxygen or the improvement of the distribution of islets in the bioreactor to avoid islet aggregates which are the origin of anoxic nuclei leading to significant cell death.

[0013] US patent 5,425,764 A1 describes an implantable artificial pancreas comprising a chamber containing the islets of Langerhans equipped with inlet and outlet channels to supply the islets, an open vascular chamber filled with foam, and a semi-permeable membrane separating the chambers. This patent attempts to address the problem of improving the lifespan of the islets by protecting them, within a chamber, from inflammatory agents, for example. However, the vascularization near the chamber, although intended to supply oxygen, also delivers molecules involved in inflammatory reactions and the development of biofouling. US patent 2018 / 0263238 also describes a device for encapsulating insulin-producing cells comprising layers formed of a first membrane and a second membrane, bonded together to form channels.Some channels contain islets, while others are islet-free, forming fluid transport channels that deliver nutrients to the islets. Although this system attempts to address the issue of nutrient delivery to the islets, it is not highly efficient because the nutrients are delivered to channels adjacent to those containing the islets, but also diffuse into the surrounding environment, which is intentionally open to vascularization. Thus, the supply of nutrients to the islets first passes through this environment, depleting the amount of nutrients available to diffuse back to the islets in other channels.

[0014] Document WO2023275134A1 is also known, describing a pancreatic cell receiving matrix comprising: a semi-permeable wall delimiting at least partially an internal volume, a porous body, preferably based on at least one polymer, disposed within the internal volume, comprising: a first set of cavities containing pancreatic cells, a second set of cavities free of pancreatic cells, the first and second sets of cavities not being fluidly connected to each other. The arrangement of the pancreatic cells in the cavity or cavities of the porous body allows control of the cell distribution within the porous body, unlike macroencapsulation solutions where the cells are fixed in a polymer matrix that has been solidified.

[0015] Another system for distributing islets in a microstructured matrix of alveoli in which the islets are trapped is described by Wang LH, Marfil-Garza BA, Ernst AU, et al (2023) Inflammation-induced subcutaneous neovascularization for the long-term survival of encapsulated islets without immunosuppression. Nat Biomed Eng 1-19.

[0016] However, for populations of varying sizes, such as islets ranging in size from 20 to 600 µm in diameter, their homogeneous distribution within these devices, which are composed of cells or cavities of a single size, is complicated. This can lead to the formation of islet aggregates in each cell and consequently create oxygen-depleted zones.

[0017] An object of the present invention is therefore to propose a solution to increase the lifespan of pancreatic cells.

[0018] The other objects, features and advantages of the present invention will become apparent from an examination of the following description and accompanying drawings. It is understood that other advantages may be incorporated. SUMMARY

[0019] To achieve this objective, according to one embodiment, a distribution and reception device for a population of pancreatic islets heterogeneously sized is provided, comprising a matrix having a first face opposite, preferably parallel, to a second face, at least one of the first and second faces extending mainly in an XY plane, characterized in that the matrix comprises concentric channels centered on a center O, the channels having, at each point, a section S, taken along a plane perpendicular to the XY plane and perpendicular to a principal extension direction Dep of the channel at that point, the section S having at least two lateral walls and a bottom wall connecting the two lateral walls, the two lateral walls defining between them an opening for receiving pancreatic cells, opening onto the first face, the bottom wall being opposite the cell reception opening,the receiving opening extending over the entire length L of the channel, taken parallel to the main extension direction Dep, the receiving opening having a width 1 taken according to section S. ,

[0020] The device is configured so that the widths of the receiving aperture of two adjacent channels, taken at points located on the same radial direction, preferably centrifugal passing through the center O and parallel to the XY plane, have an equal or increasing value when moving away from the center O and that the widths of the receiving aperture of a channel closest to the center O and of a channel furthest from the center O, taken at points located on the same radial direction, preferably centrifugal passing through the center O and parallel to the XY plane, have an increasing value when moving away from the center O.

[0021] This device allows the pancreatic islets to be distributed according to their size, limiting the formation of aggregates which present a significant mortality.

[0022] A second aspect of the invention relates to a pancreatic bioreactor intended to be implanted in the human or animal body comprising the distribution and reception device as described above and a heterogeneous population in size of pancreatic islets arranged in the channels.

[0023] A third aspect of the invention relates to a method for distributing a population of pancreatic islets of varying sizes according to their size, comprising: a. providing a distribution and receiving device as described above, b. depositing pancreatic islets at the center of said device, c. agitating the device so that the pancreatic islets are distributed into the channels according to their size.

[0024] A fourth aspect of the invention relates to a method of delivering insulin comprising the implantation of the bioreactor according to the second aspect, in a human or animal body. BRIEF DESCRIPTION OF THE FIGURES

[0025] The aims, objects, features and advantages of the invention will become clearer from the detailed description of an embodiment thereof, which is illustrated by the following accompanying drawings in which:

[0026] [Fig.1] Fig.1 represents a cross-sectional view in the XY plane of the device according to the invention.

[0027] [Fig.2] Fig.2 represents a top view along the XY plane of the device according to the invention.

[0028] [Fig.3] The [Fig.3] represents a detail of a device according to the [Fig.1].

[0029] [Fig. 4] [Fig. 4] shows a detail of the channels of a device according to [Fig. 1] in cross-sectional view in the XY plane.

[0030] [Fig. 5] Fig. 5 shows a detail of a device in cross-sectional view. XY plane according to an alternative embodiment in which the channels have a U shape.

[0031] [Fig. 6] [Fig. 6] shows a detail of a device in cross-sectional view at XY plan according to another alternative embodiment in which the channels have a U-shaped form that is narrowed at the receiving opening.

[0032] [Fig.7] Fig.7 represents a graph illustrating the quantification of the total surface area islands in the different channels of the device according to the invention.

[0033] [Fig. 8]. Fig. 8 represents a graph illustrating the average size of the islands in the different channels of the device according to the invention.

[0034] [Fig.9] Fig.9 represents a top view along the XY plane of the device according to a method of implementing spiral channels in the circular matrix.

[0035] The drawings are given by way of example and are not limiting of the invention. They constitute schematic representations of principle intended to facilitate understanding of the invention and are not necessarily to scale with practical applications. In particular, the dimensions are not representative of reality. DETAILED DESCRIPTION

[0036] Before proceeding to a detailed review of embodiments of the invention, optional features that may be used in combination or alternatively are listed below:

[0037] By way of example, the receive aperture widths 17 of all the channels 10, taken at points located on the same radial direction passing through the center O and parallel to the XY plane, have an increasing value as one moves away from the center O. That is to say, no channel 10 has the same receive aperture width 17 as the one adjacent to it. Thus, the receive aperture width 17 of each given channel 10 is less than the receive aperture width 17 of the channel 10 that is immediately adjacent to it and that at least partially surrounds that given channel 10.

[0038] By way of example, the width 1 of the reception opening 17 of different channels 10, taken at points located on the same radial direction passing through the center O and parallel to the XY plane, exhibit a maximum variation of 1000%.

[0039] By way of example, the width 1 of the receiving opening 17 of different channels 10, taken at points located on the same radial direction passing through the center O and parallel to the XY plane, have a minimum variation of 30%.

[0040] By way of example, the bottom wall 16 forms an angle 19 with the two side walls 15. The section S thus has the shape of a rectangle or polygon.

[0041] By way of example, the bottom wall 16 and the two side walls 15 form a curve. The bottom wall 16 does not form an angle with the two side walls 15, so the section S has a "U" shape or a portion of a circle or an ellipse.

[0042] By way of example, the width 1 of the receiving aperture 17 of the channels 10 varies between 50 and 800 micrometers. It may be equal to or less than the maximum distance D between the side walls 15, defined as the largest dimension taken transversely between the side walls 15.

[0043] By way of example, the depth P of the channels 10 measures between 100 and 1000 micrometers. The depth P is defined as the largest dimension of the channel taken perpendicular to the XY plane.

[0044] By way of example, the channels 10 have a closed contour in projection in the XY plane. The channels are not fluidically connected to each other other than by the diffusion of a liquid through the matrix.

[0045] By way of example, the device comprises a lid 3 made of semi-permeable material suitable for placement on the first face 6 of the matrix so as to seal the receiving openings 17 of the channels 10 and a membrane 5 having a cutoff threshold of less than 15 nm and preferably greater than or equal to 8 nm. This arrangement allows for selective permeability to block the host's immune system without altering the exchange of insulin, gases, and nutrients.

[0046] By way of example, matrix 2 is based on methacrylate gelatin, the lid is based on collagen, and the membrane is based on Polyvinyl Alcohol.

[0047] For example, the size of pancreatic islets is between 20 and 600 micrometers.

[0048] In the following description, the term "on" or "in contact" does not necessarily mean "directly on" or "directly in contact." Thus, when it is stated that a part or component Al is supported "on" a part or component Bl, this does not mean that parts or components Al and B1 are necessarily in direct contact with each other. These parts or components Al and Bl may be either in direct contact or supported by one or more other parts.

[0049] In the detailed description that follows, terms such as "longitudinal," "transverse," "superior," "inferior," "internal," and "external" may be used. These terms should be interpreted relatively in relation to the normal operating position of the device and / or bioreactor, such as an artificial pancreas. For example, the term "internal" refers to the faces or elements facing inward of the device and / or bioreactor. The term "external" refers to the faces or elements facing outward of the device and / or bioreactor. For example, with channels extending along a principal direction, "longitudinal" means parallel to this direction, and "transverse" means perpendicular to this direction.

[0050] The expression "A fluidically connected to B" or "A fluidly connected to B" is synonymous with "A is in fluidic connection with B" and does not necessarily mean that there is no component between A and B. Thus, these expressions refer to a fluidic connection between two elements, this connection being either direct or indirect. This means that it is possible that between a first element and a second element that are fluidly connected, a fluid path exists through one or more conduits, cavities, or channels, possibly an additional component, this path being distinct from the simple diffusion of the fluid through the matrix material, this path being either not including other components or not.

[0051] Conversely, the term "fluidically connected directly" refers to a direct fluidic connection between two elements. This means that between a first element and a second element which are fluidly connected directly no other element is present, other than a conduit / cavity / channel or multiple conduits / cavities / channels.

[0052] A parameter "approximately equal to / greater than / less than" a given value means that this parameter is equal to / greater than / less than the given value, to within 10% or even 5% of that value.

[0053] An element "based" on a material is understood to be an element comprising that material and possibly other materials. "Based" on a material means that said material constitutes the majority relative to any other materials.

[0054] The porosity of an element or material is understood to be the volume not occupied by the material composing it, relative to the apparent volume of the element or material. This volumetric proportion may be occupied by the surrounding medium of the element or material, a vacuum, a gas, or a liquid, for example, water. In the context of the present invention, the porosity of the material is understood to refer specifically to the channels.

[0055] By "cut-off threshold" of a membrane, body or organ, we mean the threshold molar mass or threshold dimension for which at least 90%, preferably at least 95%, preferably at least 99%, more preferably still 100%, of species of molar mass or dimension greater than or equal to the threshold molar mass or threshold dimension are blocked by the membrane, body or organ.

[0056] An islet is understood to be a group of several cells, preferably of the same type, ranging from a few cells, for example a dozen, to approximately 5,000 cells. The islet has a size between 20 and 600 µm. Pancreatic cells may be isolated or grouped together in the form of pancreatic islets. A pancreatic islet comprises at least one pancreatic cell, and preferably a plurality of pancreatic cells. The cells or islets are advantageously living. In the following description, the terms cell and islet are used interchangeably.

[0057] Device 1 and the bioreactor comprising the device are now described according to several embodiment examples.

[0058] The device 1 according to the invention is intended to distribute and receive cells or islets according to their size.

[0059] Device 1 is applicable to any type of cell, organoid, or microorganism, advantageously living, forming a population or sample heterogeneous in terms of size. More particularly, the device is applicable to the distribution and reception of pancreatic cells. The pancreatic cells may be isolated or grouped into pancreatic islets. A pancreatic islet comprises at least one pancreatic cell, and preferably a plurality of pancreatic cells. In the following, the matrix is ​​considered, by way of non-limiting agreement, to be 2 receives pancreatic islets, also called islets. Pancreatic cells are, for example, beta cells of Langerhans. Pancreatic cells can be stem cells destined to become pancreatic cells or pancreatic cells derived from stem cells.

[0060] The bioreactor comprising device 1 and cells is intended to be implanted in the human or animal body. For example, the bioreactor is intended to receive pancreatic cells, particularly islets of Langerhans; such a bioreactor forms an artificial pancreas intended to be implanted in the human or animal body in order to deliver insulin.

[0061] To receive pancreatic cells, the device includes a matrix 2 comprising channels 10 to accommodate cells.

[0062] According to a preferred embodiment, the device comprises a membrane 5 delimiting at least in part an internal volume in which the matrix 2 is disposed and advantageously a lid 3. The membrane 5 is advantageously semi-permeable.

[0063] The matrix 2 comprises a first face 6 opposite a second face 7. The first face 6 is advantageously parallel to the second face 7. The first face 6 and the second face 7 are advantageously connected by an external face 8. The external face 8 defines the thickness of the matrix 2. The external face 8 may be curved, for example in the case of a matrix 2 with a circular, oval, etc., cross-section, or it may comprise several straight portions successively connected to each other by angles when the matrix has a polygonal cross-section. Optionally, the external face 8 may be a combination of both. The external face 8 is advantageously transverse, preferably perpendicular to the first face 6 and the second face 7.

[0064] The first face 6 and / or the second face 7 extend(s) mainly along an XY plane.

[0065] The channels 10 formed in the matrix 2 to receive the cells are advantageously concentric centered on a center O. This means that the channels develop around the same point, a first channel enveloping a second, or vice versa.

[0066] The channels 10 define, in the matrix 2, a receiving volume 18 for the cells. The channels 10 are hollow and elongated.

[0067] The channels extend in a main extension direction Dep. The channels can be of various shapes, for example curved such as circular, oval, rounded, arc of a circle or straight for example polygonal as illustrated in [Fig.2].

[0068] According to one embodiment, the channels 10 can be fluidly independent. Each channel 10 is, for example, closed upon itself. The channels 10 do not have a longitudinal end. The channels 10 can have two The longitudinal ends are closed, meaning they are not fluidically connected to each other and not fluidly connected to other channels. The channels 10 are not fluidly connected to each other except by the diffusion of a liquid through the matrix 2.

[0069] According to another embodiment, the channels 10 are fluidically connected to one another, forming a spiral. The spiral formed by the channels 10 comprises two closed longitudinal ends. The channels 10 are formed of portions rotating around a fixed center O and moving away from it. Along the same radial direction passing through the center O, the portions form concentric channels.

[0070] In the case where the channels 10 are curved, their main extension direction Dep is tangent to the channel at each point of the channel.

[0071] In the case where the channels 10 are polygonal in shape, the main extension direction Dep is parallel to each side of the polygon.

[0072] The channels 10 present, at each point, a section S, taken along a plane perpendicular to the XY plane and perpendicular to the main extension direction Dep of the channel at that point.

[0073] An example of an embodiment of a device according to the invention is illustrated in Figures 1 and 2.

[0074] The device according to one embodiment is illustrated in [Fig. 2] from a top view. In [Fig. 2], there are nine channels 10. The channels 10 are concentric around point O. The channels 10 are fluidically independent of each other. The channels extend in a principal extension direction Dep and have a parallelepiped-shaped perimeter in the XY plane, in this case rectangular. In the case where the channels 10 are circular, the perimeter is the circumference of the channel 10. The perimeter can also be called the contour. The channel has a perimeter in the XY plane, which means that the contour of the channel is closed. The channel is delimited by its closed contour.

[0075] In the detailed view of [Fig. 2] on [Fig. 3], the first three concentric channels 10 from the center O are shown. Each channel 10 has a first channel portion 11,111 corresponding to a first side of the rectangle, a second channel portion 12,112 corresponding to a second side of the rectangle, a third channel portion 13,113 corresponding to a third side of the rectangle, and a fourth channel portion 14,114 corresponding to a fourth side of the rectangle. The first channel portion 11,111, the second channel portion 12,112, the third channel portion 13,113, and the fourth channel portion 14,114 are fluidically connected to form the channel.

[0076] Each part 11,111 12,112 13,113, 14,114 of each channel 10 has a section S and a main extension direction Dep, noted in [Fig.3] with the index corresponding to the part in question.

[0077] The channels 10 comprise at least two lateral walls 15 and advantageously at least one bottom wall 16. The two lateral walls 15 and optionally the bottom wall 16 define the receiving volume of the cells 18 and a receiving aperture 17. The lateral walls 15 form, for example, an angle 19 with the bottom wall 16; in this case, the cross-section S of the channel 10 is polygonal in shape. For example, the bottom wall 16 has at least one straight portion, or even several straight portions. For example, the bottom wall 16 is parallel to the XY plane and preferably, the bottom wall is parallel to the second surface 7, as illustrated in [Fig. 1] and [Fig. 4]. The bottom wall 16 defines the receiving surface of the channel. The lateral walls 15 may not form an angle with the bottom wall 16; in this case, section S of channel 10 is at least partially rounded in shape, as illustrated in [Fig.5] and [Fig.6].For example, the bottom wall 16 is rounded.

[0078] The receiving opening 17 opens onto the first face 6. The receiving opening 17 is defined between the lateral walls 15 at the level of the first face, advantageously in the XY plane. The receiving opening 17 extends over the entire length (L) of the channel.

[0079] The channels 10 are open along their entire length (L). The channels 10 are said to be surface channels on the first face 6 of the matrix 2. The channels 10 are open on the first face 6.

[0080] The receiving opening 17 has an opening width 1 taken according to section S. The opening width 1 is also called the channel width.

[0081] According to the invention, the width of the opening 1 of a different channel taken on the same radial direction passing through the center O has an increasing value as it moves away from the center O. The concentric channels of increasing size allow the cells to be distributed according to their size over the entire surface of the device.

[0082] Advantageously, the channel closest to the center O and the channel furthest from the center O have opening widths 1, taken at points located on the same radial direction, passing through the center O and parallel to the XY plane, of increasing value as they move away from the center O. The end channels are of different dimensions, the furthest channel having a larger opening width 1 than the channel closest to O.

[0083] Advantageously, two adjacent channels have opening widths 1, taken at points located on the same radial direction, passing through the center O and parallel to the XY plane, and have an equal or increasing value as they move away from the center O. Thus, two adjacent channels can have an equal width 1.

[0084] According to one embodiment, it is possible for two adjacent channels 10 to have the same width 1. In particular, more channels of medium width and fewer channels of small or large dimensions may be provided, since there are commonly few small or large islands and many medium-sized ones. The number of channels of the same size is adapted to the distribution of island sizes.

[0085] For example, for two given adjacent channels, the width 11 of a first channel is equal to the width 12 of the second channel. On the other hand, there exists at least a third channel which at least partially surrounds the first and second channels and which has a receive aperture width 17 greater than those of the first and second channels.

[0086] According to another embodiment, two adjacent channels 10 have different widths 1 and advantageously increasing as they move away from the center O. The width 11 of a receiving aperture 17 of a first channel is less than the width 12 of the receiving aperture 17 of a second channel 10.

[0087] By way of example, the width of the ducts and the number of ducts of each width are defined according to the number and probability density of the diameter of the pancreatic islets, which is specific to each species (i.e., human, porcine, etc.). The width of the ducts is determined by the distribution of the islet population according to their diameter. The number of ducts of the same width is defined based on the distribution of the islet population according to the total area occupied by each diameter.

[0088] According to one example, the width 1 of two adjacent channels exhibits a variation between 30% and 100%. For example, among two adjacent channels, the adjacent channel furthest from the center O has a width 1 that is 30% to 100% greater than the width 1 of the adjacent channel 10 closest to the center O.

[0089] By way of example, the width 1 of the receiving openings 17 varies between 50 and 800 micrometers.

[0090] The lateral walls 15 are, for example, parallel to each other. The lateral walls 15 extend transversely from the first face 6 of the matrix 2. According to one possibility, the lateral walls 15 are parallel to each other. According to an alternative possibility, the lateral walls 15 are rounded.

[0091] Each channel has a width 1 corresponding to the width of the receiving opening 17 extending parallel to the XY plane and advantageously at the level of the ends of the side walls 15.

[0092] Each channel has a depth P. The depth P is understood as the largest dimension along a direction perpendicular to the XY plane between the bottom wall 16 of the channel and the receiving opening 17. Preferably, the depth of the channels measures between 100 and 1000 micrometers.

[0093] Each channel 10 has a maximum distance D between the side walls 15. The distance D extends as the largest dimension in a direction parallel to the XY plane between the side walls 15. According to one possibility, the distance D is identical to the width 1 of the receiving opening 17. According to another possibility, the distance D is greater than the width 1 of the receiving opening 17.

[0094] Each channel has a length L. The length L is understood as the dimension taken parallel to the main extension direction Dep. The length L of a channel corresponds to the length of its perimeter.

[0095] Section S may be of various shapes. Preferably, the channels 10 are all of the same shape.

[0096] According to one embodiment, the channels 10 have a polygonal S section, more preferably rectangular, or even square.

[0097] According to another embodiment, the channels 10 have a rounded or oval S section.

[0098] The channels 10 are spaced from each other by a spacing E. The spacing E is understood as the dimension taken along the XY plane separating two adjacent channels, that is to say, the dimension between the nearest lateral walls 15 of two adjacent channels 10. By way of example, the spacing is on the order of 200 pm.

[0099] According to one embodiment, the device according to the invention, more specifically the matrix 2, may include at least one conduit and preferably conduits free of cells and configured to ensure the circulation of nutrients and gases within the matrix 2. The at least one conduit is, for example, of identical configuration to the channels 10, that is to say, in particular opening onto the first face 6. According to another example, the at least one conduit is not opening onto the first surface 6, the at least one conduit is closed around its entire perimeter and is only opening from the matrix 2 at at least one end or both of its ends.

[0100] According to one example, the matrix 2 is based on a material suitable for 3D printing. According to one example, the matrix is ​​based on a natural or synthetic polymer, preferably biocompatible and non-biodegradable.

[0101] According to one example, matrix 2 is a hydrogel, for example, made of methacrylate gelatin.

[0102] According to one possibility, matrix 2 does not have any openings 17 of 10 channels.

[0103] According to another, more advantageous possibility, the matrix 2 may be based on, or made of, a material capable of allowing the passage of nutrients and gases, as well as insulin produced by the islets, and of blocking the islets. Thus, exchanges between the cells and the outside of the device occur through the openings 17 of the channels 10 and through the matrix 2 itself.

[0104] For this purpose, the matrix material 2 may have a cutoff threshold preferably substantially greater than or equal to the molecular mass of insulin, i.e. greater than or equal to 8 nm. To block islands, the matrix 2 material may have a cutoff threshold preferably less than or equal to the minimum island size. As an example, the matrix 2 material may have a cutoff threshold of significantly less than or equal to 20 pm.

[0105] Advantageously, matrix 2 has a cutoff threshold configured to limit or even prevent the passage of inflammatory agents. Advantageously, the matrix has a cutoff threshold configured to limit or even prevent the vascularization of matrix 2.

[0106] According to one example, the device includes a cover 3 intended to seal the channels 10 more specifically the receiving openings 17. The cover 3 is intended to be applied to and to be in contact with the first face 6.

[0107] The lid 3 is preferably made of polymers / biomaterials such as collagen or chitosan. To make them non-biodegradable, they are cross-linked, for example, with glutaraldehyde or genipin.

[0108] The lid 3 has non-selective porosity. It is intended to maintain the cells in the channels 10 without limiting the diffusion of nutrients and gases, as well as the insulin produced by the islets, and serves only to block the islets.

[0109] According to one possibility, the lid material 3 may have a porosity suitable for allowing the passage of nutrients and gases, as well as insulin produced by the islets. The porosity may be configured to allow the passage of molecules with a size at least equal to that of insulin. In one example, the matrix material 2 may have a cutoff threshold greater than or equal to 8 nm. Since nutrients and gases have a molar or molecular mass less than 8 kDa, their passage through the lid material 3 is permitted. To block the islets, the lid material 3 may have a cutoff threshold preferably less than or equal to the minimum size of the islets. In one example, the matrix material 2 may have a cutoff threshold preferably less than or equal to 20 pm.

[0110] The device according to the invention is advantageously coated at least in part with a membrane 5.

[0111] According to one example, the membrane 5 is a flexible membrane covering at least part of the matrix 2.

[0112] The membrane 5 is arranged around the periphery of the matrix 2 and advantageously of the lid 3. The second face 7 and the external face 8 of the matrix are covered by the membrane 5.

[0113] The cover 3 is preferably coated on its external face, opposite to the first face 6 of the membrane device 5.

[0114] Membrane 3 is advantageously semi-permeable and can be based on or made of a material suitable for allowing the passage of nutrients and gases, as well as insulin produced by the islets, and to block immune system molecules, for example cytokines. Advantageously, membrane 5 has a cutoff threshold configured to limit or even prevent the passage of inflammatory agents. Advantageously, membrane 5 has a cutoff threshold configured to limit or even prevent the vascularization of matrix 2.

[0115] To this end, membrane 5 can have a cutoff threshold greater than or equal to 8 nm and less than 15 nm. With a cutoff threshold greater than or equal to 8 nm, membrane 5 allows communication of bodily fluid between the internal environment of the body and matrix 2 containing the islets. Thus, the nutrients necessary for the islets reach them from the internal environment, and the insulin produced by the islets can be released into this environment for the regulation of blood glucose. With a cutoff threshold less than 15 nm, the passage of immune system molecules, and in particular cytokines, into device 1 is blocked by membrane 5. Thus, the islets are protected from immune system reactions. Systemic immunosuppression in the patient can then be limited, and preferably avoided.

[0116] The device 1 can be configured so that the membrane 5 is in direct contact with the patient's body.

[0117] According to one example, the membrane 5 is based on a natural or synthetic polymer, preferably biocompatible and non-biodegradable. Preferably, the membrane 5 is based on a polymer exhibiting anti-biofouling properties.

[0118] According to one example, membrane 5 is based on or made of at least one polymer from among polyethylene glycol (PEG), polyvinyl alcohol (PVA), a copolymer (ethylene vinyl alcohol) (EVOH), hexadimethrine bromide (more commonly known by the trade name Polybrene), and carboxymethyl cellulose. The membrane thus exhibits good biocompatibility and limits biofouling phenomena.

[0119] According to one example, the reservoir comprises at least one of a nutrient for pancreatic cells and an anti-inflammatory compound.

[0120] According to one example, the fluidic module includes a pump configured to induce a flow of liquid from a liquid external to the device, for example a body fluid, into the matrix and for example into the conduits.

[0121] According to one example, the fluidic module includes a controller configured to regulate at least one parameter of the flow formation by the fluidic module.

[0122] According to one example, the device further comprises at least one anode and at least one cathode, and an electrical power source. The anode and cathode can be electrically connected to the electrical power source, so that, in the presence Using bodily fluid, a closed electrical circuit is formed to produce hydrogen at the cathode and oxygen at the anode through electrolysis of the bodily fluid. Pancreatic cells are thus preserved by the production of oxygen and hydrogen via electrolysis, thereby improving insulin release into the internal environment.

[0123] According to one example, the device is configured to electrolyze body fluid only in liquid form. The electrolyzed body fluid then does not contain any gaseous fraction.

[0124] According to one example, at least one of the cathode and the anode is disposed in the internal volume delimited at least in part by the membrane 5 of the device.

[0125] According to one example, at least one of the cathode and the anode is arranged in matrix 2. According to one example, the cathode and the anode are arranged in matrix 2.

[0126] According to one example, at least one of the cathode and the anode is disposed on, preferably directly on, matrix 2.

[0127] According to one example, the cathode and the anode are arranged in contact, preferably directly in contact, with the outer periphery of the matrix 2. According to another aspect, the invention relates to a bioreactor intended to be implanted in the human or animal body comprising the distribution and reception device and a heterogeneous in size population of cells arranged in the channels.

[0128] Advantageously, the cells are pancreatic cells.

[0129] Preferably, the cells and in particular the clusters of pancreatic cells, called pancreatic islets, have a size between 20 and 600 µm.

[0130] According to another aspect, the invention relates to a method of distributing and receiving a population of pancreatic islets of heterogeneous size according to their size.

[0131] The method first includes the provision of a distribution and receiving device as described above.

[0132] The process then includes the deposition of cells at the center O of the device. For this step, deposition by pipette is chosen, for example.

[0133] The method then comprises agitating the device so that the cells are distributed in the channels according to their size. Advantageously, the device is agitated only in the XY plane. For example, the agitation is done manually.

[0134] According to one aspect, the invention relates to a method for manufacturing the bioreactor in which, after the steps of the process of distributing and receiving a heterogeneous population in size of cells or islands of cells according to their size, the method includes the positioning of a lid 3 on the first face 6 of the matrix 2. The method advantageously includes a step of coating the matrix 2 and the lid 3 with the membrane 5. Examples

[0135] Example 1: Fabrication of a cell distribution and reception device

[0136] A device comprising a matrix 2 based on 100 mg.ml-1 methacrylate gelatin derived from bovine skin (type B) combined with Lithium phenyl-2,4,6-trimethylbenzoylphosphinate, which initiates photopolymerization upon exposure to ultraviolet light (λ=405nm). For this purpose, an Anycubic Photon Mono X (6K) printer is used to perform Digital Light Processing (DLP), heated to 42.5°C to prevent resin polymerization. The 3D matrix is ​​first designed using Computer-Aided Design (CAD) software (FreeCAD), saved as STL files (stereolithography), then transmitted to the DLP printer which produces the matrix 2 by successive layers of 100 µm thickness with 30 seconds of UV exposure. The total surface area of ​​the channels 10 is 1 cm² / 1000 Island Equivalents (IEQ).The 10 channels are of increasing size, from 150 to 400 µm wide.

[0137] Figures 7 and 8 illustrate the quantification of the total surface area (D) and the average size (E) of the islands in the different channels of the bioreactor. It can be seen that the majority of the islands are distributed within the channels (91.02%). It can also be seen that the size of the islands correlates with the sizes of the channels.

[0138] The invention is not limited to the embodiments previously described and extends to all embodiments covered by the invention.

[0139] List of references 1. Device 2. Matrix 3. Lid 5. Membrane 6. First side 7. Second side 8. Outer face of the matrix 10. Canal 11. First side of a canal 12. Second side of a canal 13. Third side of a canal 14. Fourth side of a canal 15. Side walls 16. Back wall 17. Reception opening 18. Reception volume 19. Angle side wall - back wall 111. First side of an adjacent canal 112. Second side of an adjacent canal 113. Third side of an adjacent canal 114. Fourth side of an adjacent canal O. Center S. Section Dept. Main Extension Directorate 1. Width of the receiving opening P. Canal depth D. Maximum distance between side walls E. Spacing between two adjacent channels L. Canal length

Claims

Demands

1. A device (1) for distributing and receiving a population of pancreatic islets of varying sizes, comprising a matrix (2) having a first face (6) opposite a second face (7), at least one of the first (6) and second faces (7) extending principally in an XY plane, characterized in that the matrix (2) comprises concentric channels (10) centered on a center O, the channels (10) having, at each point, a section S, taken along a plane perpendicular to the XY plane and perpendicular to a principal extension direction Dep of the channel (10) at that point, the section S having at least two lateral walls (15) and a bottom wall (16) connecting the two lateral walls (15), the two lateral walls (15) defining between them a receiving aperture (17) for pancreatic cells, opening onto the first face (6), the bottom wall (16) being opposite the receiving aperture (17) of cells,the receiving aperture (17) extending over the entire length (L) of the channel (10), taken parallel to the main extension direction Dep, the receiving aperture (17) having a width (1) taken according to section S, the device being configured so that the widths (1) of the receiving aperture (17) of two adjacent channels (10), taken at points located on the same radial direction, passing through the center O and parallel to the XY plane, have an equal or increasing value with respect to the center O and the widths (1) of the receiving aperture (17) of a channel (10)) closest to the center O and of a channel (10) furthest from the center O, taken at points located on the same radial direction, passing through the center O and parallel to the XY plane, have an increasing value with respect to the center O.,

2. Device according to the preceding claim wherein the receiving aperture widths (1) (17) of all the channels (10), taken at points located on the same radial direction passing through the center O and parallel to the XY plane, have an increasing value as they move away from the center O.

3. A device according to any one of the preceding claims, wherein the width (1) of the receiving opening (17) of the channels (10) different, taken at points located on the same radial direction passing through the center 0 and parallel to the XY plane, exhibit a maximum variation of 1000%.

4. Device according to any one of the preceding claims wherein the width (1) of receiving opening (17) of different channels (10), taken at points located on the same radial direction passing through the center O and parallel to the XY plane, have a minimum variation of 30%.

5. Device according to any one of the preceding claims in which the bottom wall (16) forms an angle (19) with the two side walls (15).

6. Device according to claim 5 in which the bottom wall (16) and the two side walls (15) form a curve.

7. Device according to any one of the preceding claims wherein the width (1) of receiving opening (17) of the channels (10) varies between 50 and 800 micrometers.

8. Device according to any one of the preceding claims wherein the depth (P) of the channels (10) measures between 100 and 1000 micrometers.

9. Device according to any one of the preceding claims wherein the channels (10) have a closed contour in projection in the XY plane.

10. Device according to any one of the preceding claims comprising a cover (3) of semi-permeable material suitable for being placed on the first face (6) of the matrix (2) so as to seal the receiving openings (17) of the channels (10) and a membrane (5) having a cut-off threshold greater than or equal to 8 nm and less than 15 nm.

11. Device according to the preceding claim wherein the matrix (2) is based on methacrylate gelatin, the lid (3) is based on collagen, and the membrane is based on Polyvinyl Alcohol.

12. A pancreatic bioreactor intended to be implanted in the human or animal body comprising the distribution and receiving device (1) according to any one of the preceding claims and a heterogeneous population in size of pancreatic islets arranged in the channels (10).

13. Bioreactor according to the preceding claim wherein the size of the pancreatic islets is between 20 and 600 micrometers.

14. A method for distributing a population of pancreatic islets of varying sizes according to their size, comprising: a. providing a distribution and receiving device (1) according to any one of claims 1 to 11; b. depositing pancreatic islets at the center 0 of said device (1); c. agitating the device (1) so that the pancreatic islets are distributed into the channels (10) according to their size.