The invention relates to a module-based cartilage cell processing device for preparing a cell seeded carrier from a biological material.
The invention further relates to a cell isolation module for use in a module-based cartilage cell processing device.
The invention still further relates to a carrier cell seeding module for use in a module-based cartilage cell processing device.
The invention still further relates to cartilage preparation module for use in a cartilage cell processing device.
The invention still further relates to a method of cartilage cell processing.
Primary cells are highly specialized cells present in the various specific types of tissue in an organism. They are involved in maintaining, repairing and supporting the function of said tissue. In most situations where a defect occurs in living tissue, some intrinsic or extrinsic reaction is triggered. The primary cells that are present in the damaged tissue may produce specific growth and other factors which will be secreted to the surrounding of the defect. This is aimed at triggering proliferation of the still viable cells whereby the defect may become filled. Next, if necessary, the cells may differentiate into the required cell type to produce and maintain fully functional specialized tissue. In many cases, however, the repair reaction of the body is not or not fully leading to a functional tissue. This may be due to a variety of reasons, such as the size of the defect, the poor availability of primary cells at the site of the defect to support the repair function, or the lack of influx from multipotent cells, which may differentiate to the required cell type, e.g. via the blood stream. Articular cartilage covers the ends of long bones of synovial joints and consists of approximately 30% of extracellular matrix proteins and approximately 70% water. Chondrocytes are the only cell type found in normal articular cartilage but contribute less then 2% of the wet weight in human healthy adult tissue. The extracellular matrix consists predominantly of cartilage specific proteoglycan molecules with highly negatively charged sulfated glycosaminoglycan (GAG side chains, as well as type II collagen fibrils. The GAG side chains are able to bind water molecules, thereby sequestering water and generating an internal swelling pressure within the cartilage matrix. These hydrogel-like properties are essential for the interstitial fluid flow patterns observed inside the matrix during functional loading of cartilage, at which point water is forced out of the tissue to an amount that allows the negatively charged GAG chains to repel each other. Upon release of the compressive load, water is imbibed back into the tissue matrix. The collagenous network, together with water bound GAG, enables articular cartilage to withstand large compressive loads which gives the tissue its unique function in synovial joints: smooth and pain-free articulation, spreading of the applied load onto the subchondral bone and absorbing mechanical shocks. Mature articular cartilage matrix is neither vascularized nor innervated, containing chondrocytes at low numbers which do not divide after skeletal maturity. It is partly for this reason that articular cartilage does not repair spontaneously or only to a very limited extent. Current approaches for cartilage repair rely on removal of tissue debris, access to the wound healing system of bone by penetrating the subchondral bone plate, and tissue transplantation and cell based therapies. Current clinical therapies are limited to autologous cell based therapies, such as autologous chondrocytes implantation (ACI) and mosaicplasty (also known as autologous osteochondral grafts). Due to severe drawbacks, both therapies can currently only address a limited share of the cartilage repair market. For mosaicplasty, a major disadvantage is the limitation to small defects due to limited availability of donor tissue for transplantation. For drawbacks include the necessity to perform two surgical operations, high costs due to the required culturing of cells in vitro, and loss of phenotype of cartilage cells. Cartilage cells de-differentiate upon cell expansion, which is part of the ACT process. Hence, they require several months after surgery before they regain their original phenotype. Only then true cartilage repair can commence. Recently, a second generation ACI has been developed involving autologous chondrocytes in a biomaterial matrix. This technique solves some of the problems of ACI, particularly the long and open surgical procedure that was required in ACI. However, three important drawbacks remain: two surgical procedures have to be carried out, high costs and long rehabilitation. Accordingly, there is a need for further improvements in the field of repair of tissue defects, in particular for defects which are not, or not sufficiently repaired in a spontaneous fashion.
It is an object of the invention to provide an efficient cell processing device. More in particular, it is an object of the invention to provide cell processing device capable of enabling a single-surgery treatment of cartilage defects, for example in a knee joint. Still more in particular, it is an object of the invention to provide a cartilage cell processing device wherein custom modification either of its hard-ware architecture and/or of the mode of operation is possible.
To this end in accordance with the invention an automated or semi-automated module-based cartilage cell processing device for preparing a cell seeded carrier from a biological material is provided, said device comprising at least a cartilage preparation module, a cell isolation module, a cell mixing module and a carrier cell seeding module.
It will be appreciated that in an embodiment only cartilage cells may be processed. Alternatively, the device according to the invention may function to allow processing of the cartilage cells and combining them with crude bone marrow, mononucleated cells from bone marrow or multipotent cells from bone marrow or other tissues prior to seeding. For the suitable carrier either scaffold or gel may be used.
It is found that substantial clinical benefits can be provided for patients when the module-based semi-automatic or fully automatic cartilage cell processing device according to the foregoing is used during a cartilage repair intervention, as the single-surgery treatment of the knee cartilage can be enabled.
An embodiment of a general cell processing device is known from WO 2006-051538. In the known device stem cells are harvested, in particular from mesenchymal and-or hematopoietic stem cells. In accordance with the known device a suitable soft tissue mass, for example a placenta or an umbilical cord are placed in a sealable container provided with an organ disrupter arranged for disrupting a structure of the organ thereby yielding a cell suspension. The disrupter is arranged as a rotatable, a translatable or a vibratable body.
A further embodiment of a cell processing device is known from US 2007-0148756. In the known device a cell suspension may be prepared. For this purpose the device comprises a movable dissociation element arranged inside a container for engaging a tissue for causing said dissociation. The dissociation element may be implemented as a blade, a serrated member, a member having surface roughness, a rotating strand, or a member having the 3D dissociation features. The blades of the known dissociation device may be triangular in shape having beveled cutting edges. The blade of the known dissociation device may be rotated with a relatively slow speed for merely distributing the tissue inside the container rather than for cutting it.
Due to the fact that the module-based cartilage cell processing device according to the invention comprises a number of separate modules, which may be removable and/or disposable, a custom automated or semi-automated cell processing system can be built having a flexible architecture. As a result, a suitable biological material can be fully automatically processed in the cartilage cell processing device according to the invention so that the cell seeded carrier, like scaffold, gel or other implantable biomaterial, can conveniently be prepared maintaining sterility. It is found to be advantageous to provide disposable modules, however, it is also possible to provide a suitable portion of the device as an reusable item. It will be appreciated, however, that using closed, preferably aseptic, disposable modules is advantageous as manual handling of the biological material between different separated modules is avoided improving sanitary quality of the procedure as a whole. However, a semi-automatic mode is also allowed, for example, when the transfer is carried out using a luerlock or a similar interface.
In general, by way of example, the process of scaffold preparation may be seen as follows. Suitable cartilage may be collected and cut, minced or mechanically processed in a different way to form a chopped cartilage. The chopped cartilage may be further processed for chondrocyte isolation using, for example, a process of digestion followed by a process of isolation and washing of the desired cells. The thus formed and prepared biological material, which may contain a suitable buffered cell suspension, may be counted together with suitable cells (mononuclear cells and/or multipotent cells) which may be prepared using filtering red blood cells, removing plasma and washing the remaining cells. It will be appreciated that the mononuclear cells and/or multipotent cells may be derived from tissue, bone marrow or from any other suitable source. After the cells are counted the biological material may be mixed, whereby the cell quantity may additionally be determined before the step of mixing. After the step of mixing is completed, the cells may be seeded on a prepared scaffold, which may be further sized or otherwise processed prior to implanting. More details on this process will be provided with reference to
In an embodiment of the cartilage cell processing device according to the invention the cell mixing module and a carrier cell seeding module are integrated.
It is found to be particularly advantageous to integrate the mixing step and the carrier cell seeding step in one module. As a result no transport of biological material is required and the accuracy of both the mixing and the seeding may be increased.
For example, by using a suitable reservoir may be used for mixing/seeding which collects cells from a suitable module of the device according to the invention after the cells have been released. The reservoir may achieve a homogeneous population of cells. More details on this embodiment will be discussed with reference to
In a further embodiment of the cartilage cell processing device according to the invention the cartilage preparation module comprises a cutter and/or a blender.
Preferably, the cutter is a sheer cutter comprising a blade. However, a plurality of blades may be used. The blade may be manufactured from a plastics material. However, metal may be used as well. The blender may also comprise a blade which may be rotatable in two directions. In accordance with a further aspect of the invention each rotating direction of the blade may cause a substantially unique effect on the cartilage cells present in the blender. For example, a first rotating direction may be used for exerting shear forces on the biological material and the second direction may be used for massaging and pressing the biological material. This has an advantage of enabling preparation of a substantially homogeneous biological mass. However, the cutter may be adapted to push cartilage through a grid of blades or cutting wires. The blender is further adapted to combine a cutting step with a gyration or whirling step.
As a result the blender is adapted to combine a cutting step with a mixing or gyration and whirling steps. More details on these embodiments will be given with reference to
In a still further embodiment of the cartilage cell processing device the cell isolation module comprises a filter having a release buffer and/or a centrifugation unit. An embodiment of the cell isolation module is discussed with reference to
Preferably, the counter is operable using a principle selected from: a bulk through flow, a slide sample or a sample through flow. It will be appreciated that a suitable counting module may be used for counting of the isolated cells and/or for counting of the chondrocyte cells. Preferably, the counted is adapted to be suitable for counting both the chondrocyte cells and the cells. The counting may be performed within a relatively short period of time, less than a minute, for example.
The bulk through flow counting method may be used in the cartilage cell processing device according to the invention. Such counting may be carried out when the cells pass through a precision orifice, which may be less than 0.1 mm in diameter. The restriction forces the cells into a single file. It may be preferable that a passage used for accommodating the cell flow is adapted for causing a laminar flow. This measuring method may be based on a variance in the electrical impedance of an electrolyte comprising particles as they pass through the orifice. Still another method of measuring may be base on optical properties of a suitable light beam, such as a laser, impinging on the cells which are forced into a single file. The laser beam may cause hydrodynamic focusing. When the cells pass in a laminar flow and intercept the laser beam the light is scattered, which may be monitored by a suitable detector.
Slide sample counting method may be used as an alternative. However, it will be appreciated that slide based systems may be destructive and may require additional strains or fluorescent dyes, but can perform measurements which are quick are reproducible. The volume of sample required for carrying out such counting is about 20 micro liter. The optimum total number of cells required for a test may be dependent on the desirable speed of counting. Preferably, about 40 cells per quadrant may be used at a sample volume of 20 micro liter yielding a minimum sample concentration of 6000 cells/ml.
Sample through flow method may be still further suitable embodiment of a counting method used in the cartilage cell processing device according to the invention. This method requires preparation of a representative sample of the cell solution in terms of cell concentration and volume, adding the required dyes or fluorescent tags and passing it through a counting and viability device, such as a flow cytometer. This method usually utilized fluorescent antibody tags on cells which are sorted by passing cells through a suitable nozzle adapted to break the stream of cells into drops. A charge is applied to the thus formed drops and they are sorted by an electric field.
It is also possible to count cells using an image analysis of a suitably stained slide.
In a further advantageous embodiment the carrier cell seeding module is integrated with a mixing unit. Preferably, it comprises at least a partially disposable syringe or a concentration tip. More detail on this embodiment will be presented with reference to
In a still further embodiment of the cartilage cell processing device according to the invention the carrier cell seeding module is arranged to measure a volume of the cell suspension in order not to overflow the carrier using a measuring device. A counter and a measuring device may be used for two different purposes:
This feature is found to be advantageous, because the accuracy of the automated carrier seeding may be improved to a further extent. For example, when the system detects that there is not enough biological material for preparing a desired carrier cell seeding, a warning signal may be given signaling that the counting number of a suitable matter, for example, chondrocytes is not optimal.
It will be appreciated that in order to improve sterility requirements regarding the scaffold preparation procedure, at least one of the modules of the cartilage cell preparation device may comprise suitable antibiotics. However, alternatively, the solutions used in the module-based device according to the invention may be provided with antibiotics instead.
The invention further relates to a cell isolation module for use in a module-based cartilage cell processing system for preparing a cell seeded carrier from a biological material, said module comprising a filter having a release buffer and/or a centrifugation unit.
In an embodiment, the cell isolation module is adapted to cooperate with a further module of the module-based cartilage cell processing system and is further adapted to measure a volume of the cell count in order not to overflow the carrier using a counter, said counter preferably being operable using a principle selected from: a bulk through flow, a slide sample or a sample through flow. Preferably, at least a part of said module is disposable.
In a further embodiment, wherein the biological material comprises red blood cells, the cell isolation module is operable using a method to lyse the red blood cells, preferably using NH4Cl.
For, example the mononuclear cells may be isolated from red blood cells using the following steps:
The invention still further relates to a cartilage preparation module for use in a module-based cartilage cell processing device, wherein the cartilage preparation module comprises a cutter and/or a blender.
The invention still further relates to a cartilage cell seeding module for use in a module-based cartilage cell processing system for preparing a seeded scaffold comprising a disposable syringe.
A method of cartilage cell processing, according to the invention, comprises the following sequence of automated steps:
For the carrier either a scaffold, gel or other implantable carrier may be used. Suitable examples of the scaffold, gel or other implantable carrier are poly(ethylene glycol)terepthalate (PEGT) and poly(butylene terephtalate (PBT) polymers, collagen scaffold or gel, esterified hyaluronic acid scaffolds, fibrin glue, alginate, hyaluronic acid, PLGA, PEG based scaffolds or gels, Polyacrylamide carriers, Dextran based carriers like cross-linked Dextran-tyramine hydrogel and self assembly based gels, and derivatives thereof. It will be appreciated that the above examples are neither limiting nor exhaustive. It will be further appreciated that further examples of suitable carriers which may be practiced with the present invention are described in a patent publication WO2005/087239 of the Applicant.
These and other aspects of the invention will be further discussed with reference to drawings wherein like reference numbers refer to like elements. It will be appreciated that the drawing are provided for illustrative purposes only and may not be used for limiting the scope of the appended claims.
a presents a schematic view of an embodiment of a blender which may be used in the cartilage cell processing device according to the invention.
b presents a schematic view of an embodiment of a blender blade which may be used in the cartilage cell processing device according to the invention.
At step 2 cartilage preparation may be carried out. It will be appreciated that cartilage cutting may be critical to the following process parameters:
It is found that an automated cutting using a suitable cutting device is beneficial for producing high yield of cells having good quality. Plastics cutting blades, which may be used in a shear cutter or blender may be advantageous. It is found that a shear cutter is capable of producing pieces of cartilage with a substantially constant size.
A blender may be used as an alternative embodiment for preparing the cartilage pieces at step 2 of
Another advantage in using the blender is that it may be integrated with mixing of collagenase and/or with a digestion step. Preferably, the blender is sealed which is beneficial in terms of sterility. The blender may be adapted to provide both cutting and vortexing, which may advantageous reduce the digestion time under 30-45 minutes, or so.
It will be appreciated that the step 2 as is described with reference to the foregoing may be carried out using a dedicated hardware outside the device according to the invention as depicted in
At step 4 chondrocyte isolation is carried out, in a module of the automated device according to the invention. The chondrocyte isolation step may be accompanied by a digestion and a washing step. It is found that chondrocyte isolation may be sensitive to isolation conditions which may affect cell numbers, cell viability, cell quality and digestion time. It is found to be preferable to carry-out the step of isolation at temperature of 37 degrees Celsius, using a buffer medium, such as MEM or RPMI, and an optimized mixing mode.
At step 8 the chondrocyte cells may be counted using a suitable counting method 8a, as is described with reference to the foregoing.
Parallel to steps 2-8, it is possible to carry out the step 6 of MNC preparation, preferably using a dedicated MNC preparation module. The user may add bone marrow biopsy, any required fluids to the MNC module to process the MNC cells in, for example, RPMI.
The step 6 may include the additional steps, such as the step of lysing or filtering out red cells; separating MNC from plasma, lysing with a suitable buffer, etc. Also cell washing may be envisaged as well as adding a suitable cell buffer, such as RPMI.
The isolated MNC is followed to the counting stage at step 8, wherein the MNC yield is counted using a counter 8b. Preferably, the counting method used for chondrocyte is the same as the counting method used for the MNC cells so that a universal counting stage may be used. This has an advantage of simplifying the architecture of the overall device.
At step 10 after the cells are counted, the cell mixing is taking place. For example, all chondocytes may be added at this step followed by an additional measurement of the quantity of MNC. After the cells are suitably mixed, the excess cell buffer, such as RPMI may be removed.
The step 10 is followed by the step 14 of cell seeding on a scaffold preparation provided at step 12. It will be appreciated that particular advantages are provided when the steps of mixing and seeding are carried out using the same hardware module.
After the prepared scaffold is seeded, the resulting biological material may be further processed, for example it may be suitably sized and implanted.
The device 20 comprises a cartilage preparation module 21 comprising a cutter/digester unit, a fluid supply port for supplying an enzyme or a washing fluid. The cartilage preparation module may have an internal volume of about 5 ml. An exit port of the cartilage preparation module 21 may be provided with a suitable filter.
It this embodiment the device 20 further comprises an MNC module 22 comprising a suitable isolation unit, such as a filter 23 and a pump. The MNC module 22 is connected via a conduit 22a with the mixing/seeding module 29 provided with a syringe 29a.
The MNC module 22 may be further provided with a waste reservoir 25 for collecting plasma, for example. The MNC module may be operable using an affinity filter or using a suitable centrifuge device.
The device 20 further comprises a suitable reservoir 24 for accommodating buffer, such as PMI which are used during the process of preparing a biological material for scaffold seeding. The tip cutter 26 may be used for opening the otherwise closed syringe 29a of the mixing and seeding module 29. The prepared cells are seeded using the syringe 29a onto a scaffold sample 27a provided on a displaceable scaffold support table 27. Preferably, the scaffold support table is rotatable and comprises a plurality of nests for accommodating different scaffold samples.
View 30b depicts schematically an embodiment of the cutting/digesting unit, wherein cutting of the cartilage is carried out using shear blades. Using shear blades has an advantage that a substantially equally sized pieces of the cartilage are provided. In order to improve release of the cartilage from the blades a specific coating may be provided thereon.
View 30c depicts schematically an embodiment of a blender which may be suitable to be used in the cutting/digesting unit 21. The blender may be provided with a blade manufactured from a plastics material. More details on the blender are presented with reference to
a presents a schematic view of an embodiment of a blender 40 of the cartilage cutting and digesting module 21 discussed with reference to
The blender 40 comprises an input fluid port 41 and for supplying enzyme and/or washing fluid into the inner volume of the blender. The inner volume of the blender may be about 5 ml. Views 40a and 40b depict schematically a cross-section of the blender along a horizontal line. The blade 44 is motorized and is preferably adapted with an angulated tip having a longer portion 42a and a shorter portion 42b. It will be appreciated that the blade 44 may be a substantially flat body, or, alternatively it may have a shape of a propeller.
In view 40a a first mode of operation is depicted, wherein the blade is moving with the longer portion 42a as a leading end. In this case the blade will exert a cutting action on the pieces of cartilage 43 and provide a suitable manner to cut the cartilage pieces for optimal digestion.
In view 40b a second mode of operation of the blade 44 is depicted, when the blade is moving with its shorter side 42b as the leading end. Because there is a space between the shorter end 42b of the blade and the wall 42 of the cutter/digester, which space is comparable with the dimensions of the cartilage pieces 43, such mode of the blade's rotation will exert a massaging action on the cartilage.
As a result, when the first mode and the second mode are alternated an improvement of the cartilage may be achieved due to such alternating mechanical action on the cartilage material.
In a preferred embodiment of the MNC isolation module, it is connected to an affinity filter 52. The conduit 51b may be used for supplying bone marrow to the MNC isolation module 51. The conduit 51d may be optional for additionally removing red cells using a washing step. A suitable release fluid may be supplied to the affinity filter 52 from a connected reservoir 53. When the MNC cells are isolated, the waste may be discharged using a reservoir 54. The isolated and harvested MNC may be supplied using the conduit 51c together with the release fluid supplied from the reservoir 53 to the mixing and seeding device 29, as is described with reference to
It will be appreciated that the modules as discussed with reference to
Although specific reference may have been made above to the use of embodiments of the invention in the context of cartilage cell processing, it will be appreciated that the invention may be used in other applications as well. While specific embodiments have been described above, it will be appreciated that the invention may be practiced otherwise than as described. The descriptions above are intended to be illustrative, not limiting. Thus, it will be apparent to one skilled in the art that modifications may be made to the invention as described in the foregoing without departing from the scope of the claims set out below.
Number | Date | Country | Kind |
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1159252.3 | Mar 2011 | EP | regional |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/NL12/50182 | 3/22/2012 | WO | 00 | 11/20/2013 |