Chip device for an organ-on-a chip (OOC)

Abstract

Chip device (10) for an organ-on-a chip (OOC), comprising: - a chip (20) comprising a culture chamber (22) for housing a cellular structure; - a pressure generating system for exerting a compression action upon the cellular structure housed in the culture chamber (22); wherein the pressure generating system comprises: - a chamber body (40) having a pressure chamber (42); - a membrane (80) having a first side (82) facing the culture chamber (22) and a second side (84) facing the pressure chamber (42), - a pressure generator (90) for supplying a work fluid to the pressure chamber (22) and building a pressure in the pressure chamber (22) that moves said membrane in the direction of the culture chamber (22) to execute a compression action upon the cellular structure contained therein. The chip device is characterized in that it comprises a support element (60) supporting the membrane (80), which is arranged between the chip (20) and the chamber body (40) of the pressure generating system.

Description

[0001] "Chip device for an organ-on-a chip (OoC) "

[0002] ★ ★ ★

[0003] TEXT OF DESCRIPTION

[0004] Technical field of the invention

[0005] The present invention relates to a chip device for an organ-on-a chip ( OoC ) .

[0006] The chip device described herein comprises a microfluidic structure typical of organ-on-chip systems , including at least one culture chamber in fluid communication with inlet and outlet channels , enabling the continuous or intermittent perfusion of culture media . This microfluidic arrangement allows for the reproduction of physiologically relevant mechanical stresses and nutrient gradients , thus mimicking in vivo tissue environments .

[0007] As already known in the art , an OoC is a cell culture system which can recreate a complex microenvironment and mimic human physiology for cell cultivation .

[0008] A preferred application of the chip device described here is for 3D cell cultivation .

[0009] In particular, the present invention relates to a chip device of the type comprising :

[0010] - a chip comprising a culture chamber for housing a cellular structure ; a pressure generating system for exerting a compression action upon the cellular structure housed in the culture chamber ; wherein the pressure generating system comprises :

[0011] - a chamber body having a pressure chamber ;

[0012] - a membrane having a first side facing the culture chamber and a second side facing the pressure chamber, and a pressure generator for supplying a work fluid to the pressure chamber and building a pressure in the pressure chamber that moves said membrane in the direction of the culture chamber, thus executing a compression action upon the cellular structure contained therein .

[0013] A chip device of the type indicated above is already known, e . g . from WO2016174607A1 .

[0014] The present invention aims to reali ze a chip device that is improved with respect to the chip devices of the prior art , particularly from the point of view of ef fectiveness and controllability of the compression action exerted upon the cellular structure .

[0015] Summary of the invention

[0016] The present invention relates in a general way to a chip device to Claim 1 .

[0017] The present invention also relates to a method according to Claim 16 .

[0018] The claims form an integral part of the teachings provided here .

[0019] Brief description of the drawings and detailed description of one or more embodiments of the invention Further characteristics and advantages of the invention will be apparent from the following description, which refers to the attached drawings provided purely by way of non-limiting example , in which :

[0020] - Figure 1 shows a preferred embodiment of the device described here , according to a perspective view;

[0021] - Figure 2 shows the device of Figure 1 in a disassembled condition;

[0022] - Figure 3 shows a cross section view of the device of Figure 1 , along section plane I I I- I I I illustrated in Figure 1 ;

[0023] - Figure 4 is a plan view of a component of the device of Figure 1 .

[0024] The following description illustrates various speci fic details intended to provide a deeper understanding of the embodiments . The embodiments may be reali zed without one or more of the speci fic details , or with other methods , components or materials , etc . In other cases , known structures , materials or operations are not shown or described in detail , to avoid obscuring various aspects of the embodiment .

[0025] The references used here are purely for convenience and therefore do not define the scope of protection or the extent of the embodiments .

[0026] As mentioned above , the device described here is a chip device for an organ-on-a chip ( OOC ) .

[0027] With reference to the figures 1 to 3 , the chip device - which is indicated as a whole by the reference numeral 10 - comprises :

[0028] - a chip 20 , which comprises a culture chamber 22 for housing a 3D cellular structure ;

[0029] - a chamber body 40 having a pressure chamber 42 ; and

[0030] - a membrane 80 having a first s ide 82 facing the culture chamber 22 and a second side 84 facing the pressure chamber 42 .

[0031] The chip 20 comprises a microfluidic structure incorporating the culture chamber 22 , which is configured for the perfusion of a culture fluid .

[0032] In the chip device 10 here described, the membrane 80 is carried by a support element 60 arranged between the chip 20 and the chamber body 40 .

[0033] A cover 50 is placed against the chamber body 40 , at a side opposite to the support element 60 , to close the pressure chamber 42 ( the cover 50 is not shown in figure 2 ) .

[0034] The above-indicated components are assembled together according to a layered formation, in the following succession ( starting from the bottom with reference to figure 3 ) : chip 20 , support element 60 with membrane 80 , chamber body 40 and cover 50 .

[0035] The chip device 10 comprises locking members 30 which engage the components above indicated to exert on them locking forces pressing together the components .

[0036] The pressing locking forces have also the function of reali zing a sealing connection between the regions in reciprocal contact of the components , so as to avoid leaks to the outside from the culture chamber 22 and the pressure chamber 42 .

[0037] The chip device 10 further comprises a pressure generator 90 for supplying a work fluid to the pressure chamber 42 and building therein a pressure acting upon the second side 84 of the membrane 80 to move the latter in the direction of the culture chamber 22 .

[0038] The person skilled in the art will understand that the movement of the membrane 80 is actually the result of the deflection the membrane undergoes , due the pressure built in the pressure chamber 42 .

[0039] In operation, this movement of the membrane 80 is able to subj ect to compression the cellular structure contained in the culture chamber 22 of chip 20 .

[0040] The pressure generator 90 may comprise e . g . a microfluid flow controller which can control the fluid flow supplied to the pressure chamber 42 based on s ignals indicative of the pressure inside the same pressure chamber 42 .

[0041] In one or more preferred embodiments , such as the one illustrated, the chip 20 is in the form of a plate having a cavity 21 in a central region, which opens out on an upper surface 26 of the chip (with reference to Figure 3 ) .

[0042] In one or more preferred embodiments , such as the one illustrated, the cavity 21 includes a chamber 22 defining the culture chamber, which is delimited on three sides by corresponding internal edges of the chip 20 , and a channel 23 which extends next to the chamber 22 and along the one open side thereof , and which is in fluid communication with the same chamber 22 .

[0043] This architecture is configured as a microfluidic structure .

[0044] The channel 23 has one end 23A which communicates with an inlet 24 and an opposite end 23B which communicates with an outlet 25 , both the inlet 24 and the outlet 25 being located at a lower surface 28 (with reference to figure 4 ) of the chip 20 .

[0045] The inlet 24 and the outlet 25 are intended to be connected to a supply system for supplying a culture fluid .

[0046] In operation, the culture fluid supplied by the supply system enters the chip 20 via the inlet 24 , flows along the channel 23 passing at least partially to the culture chamber 22 , and the remaining part of it exits the chip 20 via the outlet 25 ; eventually, some culture fluid already in the culture chamber 22 moves back to the channel 23 to be replaced by the new culture fluid supplied .

[0047] In one or more preferred embodiments , such as the one illustrated, in the culture chamber 22 , there are arranged confinement elements 29 dividing the culture chamber 22 into at least a first compartment 22A and a second compartment 22B .

[0048] Preferably, the two compartments 22A, 22B are divided along a line T that runs parallel to the channel 23 , so that one compartment ( i . e . compartment 22A in the example illustrated) finds itsel f next to the channel 23 , and the other compartment ( i . e . compartment 22B in the example illustrated) finds itsel f next to the previous compartment and, with respect to the it , opposite to the channel 23 . The confinement elements 29 are such that they delimit the two compartments 22A, 22B without determining a complete separation between the two , that is to say the culture fluid can flow from one compartment to the other without any particular restriction to do so .

[0049] In one or more preferred embodiments , such as the one illustrated, the confinement elements 29 are cylindrical posts erected from the bottom of the culture chamber 22 and arranged in a row along the line T and equally spaced from one another .

[0050] In one or more preferred embodiments , such as the one illustrated, confinement elements 29 are also provided to divide the channel 23 from the culture chamber 22 .

[0051] In one embodiment , the chip 20 includes an additional channel that places the culture chamber 22 in fluid communication with the external environment , allowing for the introduction and retrieval of synovial fluid, cell-laden hydrogel , or cel l culture medium while the chip device remains fully assembled, without requiring disassembly of its components .

[0052] Preferably, the chip 20 is made by 3D printing, e . g . by stereolithography or Digital Light Processing ( DLP ) . A UV-curable resin may be used . It is noted that fabrication by Digital Light Processing ( DLP ) allows rapid and relatively cheap customi zation and prototyping of the chip design . Preferably, the chip 20 is transparent .

[0053] In one or more preferred embodiments , such as the one illustrated, the chamber body 40 is also in the form of a plate , and has a central through opening 41 , traversing the entire thickness of the chamber body 22 and defining the pressure chamber 42 .

[0054] The opening 41 is positioned in the pressure body 40 so as to be superimposed to the cavity 21 of the chip 20 .

[0055] Preferably, the opening 41 covers in plan view an area enclosing the area of the cavity 21 .

[0056] In one or more preferred embodiments , such as the one illustrated, the chamber body 40 comprises an inlet 43 and an outlet 44 which both communicate with the pressure chamber 42 and which are connected to the pressure generator 90 .

[0057] The cover 50 is arranged against an upper surface 45 of the chamber body 40 to close the opening 41 and define an upper wall of the pressure chamber 42 .

[0058] Preferably, the cover 50 is transparent .

[0059] Preferably, the chamber body 40 is also made by 3D printing .

[0060] In one or more preferred embodiments , such as the one illustrated, the support element 60 is also in the form of a plate and it has a central region 62 on which the membrane 80 lies in extended fashion and is fixed thereto .

[0061] Preferably, the membrane 80 is fixed to a lower surface 61 of the support element 60 (with reference to figure 3 ) .

[0062] In its central region 62 , the support element 60 has a through opening 63 which is completely covered by the membrane 80 .

[0063] The opening 63 sets the second side 84 of the membrane 80 into fluid communication with the pressure chamber 42 of the chamber body 40 .

[0064] In operation, the pressure built in the pressure chamber 42 deflects the membrane 80 to move it in the direction towards the culture chamber 22 .

[0065] Because the opening 63 is smaller in terms of area occupied in plan view than the membrane 80 , only a selected portion 80 ' of the membrane 80 - the one covering the opening 63 - is subj ected to the movement indicated above .

[0066] The selected portion 80 ' is determined by the configuration of the opening 63 , speci fically its position, shape and dimension .

[0067] In one or more preferred embodiments , such as the one illustrated, the selected portion 80 ' is such that it extends exclusively over one of the two compartments 22A, 22B of the culture chamber 22 .

[0068] Preferably, the selected portion 80 ' extends over the compartment 22B, i . e . the one compartment that is spatially separated from channel 23 by compartment 22A.

[0069] In one or more preferred embodiments , such as the one illustrated, the support element 60 comprises an outer region 64 at least partially surrounding the central region 62 and having an upper contrast surface

[0070] 65 and a lower contrast surface 66 .

[0071] Incidentally, by contrast surface it is here meant a surface intended to bear the loads and forces acting on the component the surface is part of .

[0072] In the assembled condition of the device , the upper contrast surface 65 contacts a lower surface 46 of the chamber body 40 , whereas the lower contrast surface 66 contacts the upper surface 26 of the chip 20 . Both the lower surface 46 of the chamber body 40 and the upper surface 26 of the chip 20 define themselves contrast surfaces cooperating with the contrast surfaces 65 and

[0073] 66 of the support element 60 .

[0074] In one or more preferred embodiments , such as the one illustrated, in the outer region 64 , the support element 60 has a plurality of through openings 67 running from the contact surface 65 to the contact surface 66 .

[0075] Preferably, the plurality of holes 67 comprises two parallel rows of equally-spaced holes 67 that are arranged at opposite sides with respect to the opening 63 .

[0076] Moreover, also the other components of the layered- formation of the chip device 10 , namely the chip 20 , the chamber body 40 and the cover 50 , have respective pluralities of through holes , 27 , 47 and 57 , al l in corresponding positions such that they align with the holes 67 of the support element 60 .

[0077] The above indicated holes are configured to receive the locking members 30 .

[0078] The support element 60 may be made e . g . of polystyrene sheets . Opening 63 and holes 67 may be made by micro-milling .

[0079] The membrane 80 may have a thickness in the range of 150 - 350 micron and may be fabricated by spin coating directly on the support element 60 ; the latter may be subj ected to plasma oxygen activation to facilitate bonding of the membrane 80 . In alternative embodiments , the membrane 80 may also be formed by means of other fabrication techniques , including manual casting, slot die coating, doctor blade coating, or electrospinning .

[0080] It can now be noted that the support element 60 is such that the pressing locking forces exerted by the locking members 30 act exclusively upon the outer region

[0081] 64 of the support element 60 ; conversely, the central region 62 and the membrane 80 are subj ected to pressing force much lower than the locking pressing forces .

[0082] In this way, there is no risk that the membrane 80 deflects from its planar condition due to excessive pressing forces acting on it .

[0083] On this respect , the Applicant has veri fied that without the support element 60 ( see e . g . the chip device disclosed in the prior art document WO2016174607A1 cited at the beginning) , i f the membrane is squeezed with locking pressing forces , the membrane assumes a deflected state already in rest condition, i . e . when in the pressure chamber no pressure is built by the pressure generator, which may af fect the operability of the membrane .

[0084] It is then clear that the chip device described here can operate the membrane 80 more precisely and ef fectively .

[0085] With reference to figure 3 , the inner region 62 of the support element 60 is illustrated as being provided with a recess 68 configured to receive the membrane 80 so that the first side 82 of the latter is positioned at the same level of the contrast surface 66 of the support element . It follows that the contrast surface 66 is able to contact the upper surface 26 of the chip 20 .

[0086] However, it should be noted that , in order to obtain this , the above indicated recess is not essential ; in fact , the Applicant has veri fied that , even in the absence of the recess 68 and with the membrane 80 lying below the contrast surface 66 before assembling, the locking pressing forces generated by the locking members 30 are such that they bend the support element 60 to ultimately bring the contrast surface 66 in contact with the upper surface 26 of the chip 20 .

[0087] In one or more preferred embodiments , such as the one illustrated, the locking members 30 are releasable locking members , preferably of fast connection type .

[0088] Preferably, the locking members 30 include bolts and nuts .

[0089] Thanks to the above features , the chip device 10 can be easily disassembled, e . g . to enable extraction of the cellular structure or of part of it , and eventually it can then be assembled again for further operations .

[0090] Since the membrane 80 is carried by the support element 60 and through the latter it is assembled to the other components of the device , there is no risk that the membrane 80 gets damaged during the assembling and disassembling operations .

[0091] In one or more preferred embodiments , such as the one illustrated, the chip device 10 also comprise a control unit 70 for controlling the pressure generator 90 .

[0092] In particular, the control unit 70 is configured to selectively activate and deactivate the pressure generator 90 according to a mechanical stimulation routine to execute on the cellular structure .

[0093] The person skilled in the art will understand that the intensity of the mechanical stimulation depends on the length of the movement performed by the selected portion 80 ' of the membrane 80 .

[0094] In fact , the deeper this portion goes into the culture chamber 22 the higher is the compression exerted on the cellular structure .

[0095] In one or preferred embodiments , the chip device 10 can also adj ust the intensity of the mechanical stimulation executed on the cellular structure .

[0096] To this end, the control unit is configured to control the end position of the movement of the selected portion 80 ' in the direction of the culture chamber 22 by adj usting the pressure built in the pressure chamber 42 by the pressure generator 90 .

[0097] The range of stimulation through which the device can operate may vary based on the needs of the speci fic applications .

[0098] Moreover, as already indicated above , the opening 63 of the support element 60 enables to determine a selected portion 80 ' of the membrane 80 to act on a speci fic region or compartment of the culture chamber 22 according to the needs of the speci fic applications .

[0099] Now referring again to WO2016174607A1 , it is noted that the solution described therein conversely provides that the end position of the movement of the membrane be defined by the same confinement elements that are in the culture chamber, which, to this purpose , act as abutting members to stop the movement of the membrane .

[0100] In this case , the stimulation performed on the cellular structure cannot be regulated but it is actually fixed, since it is dictated by the geometry of the confinement members . Moreover, the membrane action necessarily involves the entire culture chamber, whereas it cannot be restricted to a speci fic region of the culture chamber .

[0101] Besides , this solution of prior art also suf fers from the inconvenience that the membrane may be damaged by the confinement members .

[0102] In view of the above , it is now evident how the chip device here described overcomes many of the drawbacks of the prior art .

[0103] Clearly, provided that the principle of the invention is retained, the details of construction and forms of embodiment can be varied, even to a signi ficant degree , from what has been illustrated herein purely by way of non-limiting example , without thereby departing from the scope of the invention, as defined in the attached claims .

Claims

CLAIMS1. Chip device (10) for an organ-on-a chip (OOC) , comprising :- a chip (20) comprising a culture chamber (22) for housing a cellular structure; a pressure generating system for exerting a compression action upon the cellular structure housed in the culture chamber (22) ; wherein the pressure generating system comprises:- a chamber body (40) having a pressure chamber (42) ;- a membrane (80) having a first side (82) facing the culture chamber (22) and a second side (84) facing the pressure chamber (42) ,- a pressure generator (90) for supplying a work fluid to the pressure chamber (22) and building a pressure in the pressure chamber (22) that moves said membrane in the direction of the culture chamber (22) to execute a compression action upon the cellular structure contained therein; said chip being characterized in that it comprises a support element (60) supporting the membrane (80) , which is arranged between the chamber body (40) and the chip (20) .

2. Chip device according to claim 1, wherein the support element (60) has an inner region (62) to which the membrane (80) is fixed and which has a through opening (63) configured to enable only a selected portion ( 80 ’ ) of the membrane (80) to move in the direction of the culture chamber (22) , and wherein the support element (60) has an outer region (64) surrounding at least partially the inner region ( 62 ) ; said chip device (10) comprising locking members (30) configured to exert locking forces pressing thechamber body (40) and the chip (20) against the outer region (62) of the support element (60) .

3. Chip device according to claim 2, wherein the outer region (64) of the support element (60) comprises a first contrast surface (65) contacting the chamber body (40) , and a second contrast surface (66) contacting the chip (20) , and wherein the pressing locking forces generated by the locking members (30) push the chamber body (40) against the first contrast surface (65) , and the chip (20) against the second contrast surface (66) .

4. Chip device according to claim 3, wherein, in and along the outer region (64) , the support element (60) has a plurality of holes (67) running from the first contrast surface (65) to the second contrast surface (66) , and wherein the chip (20) and the chamber body (40) have respective pluralities of holes (47, 67) in corresponding positions such that they align with the plurality of holes (67) of the support element (60) ; and wherein the locking members (30) are received in the holes of each one of the support element (60) , the chip (20) and the chamber body (40) .

5. Chip device according to claim 4, wherein the chip (20) has a third contrast surface (26) contacting the first contrast surface (66) of the support element, and the chamber body has a fourth contrast surface (46) contacting the second contrast surface (65) of the support element, and wherein the plurality of holes (27) of the chip (20) are arranged in and along the contrast surface (26) of the chip (20) , and the plurality of holes (47) of the chamber body (40) are arranged in and along the contrast surface (46) of the chamber body (46) .

6. Chip device according to any one of the preceding claims, wherein the locking members (30) are releasable locking members allowing assembling and disassembling of the chip device.

7. Chip device according to any one of the preceding claims, wherein the opening (63) of the support element (60) is such that the selected portion (80' ) of the membrane (80) extends exclusively over a partial region of the culture chamber (22) .

8. Chip device according to any one of the preceding claims, wherein, in said culture chamber (22) , confinement elements (29) divide the culture chamber (22) into at least a first compartment (22A) and a second compartment (22B) , and wherein said opening (63) of the support element (60) is such that the selected portion ( 80 ’ ) of the membrane (80) extends exclusively over the first compartment (22A) or the second compartment (22B) .

9. Chip device according to any one of the preceding claims, wherein the chamber body (22) comprises an inlet (43) and an outlet (44) in fluid communication with the pressure chamber (42) and wherein the pressure generator (90) is connected to the inlet (43) and the outlet (44) for suppling the work fluid to the pressure chamber and building therein a predetermined pressure.

10. Chip device according to any one of the preceding claims, wherein the chip (20) comprises an inlet (24) and an outlet (25) which are in fluid communication with the culture chamber (22) and which are configured to be connected to a supplying system for supplying a culture fluid to the culture chamber (22) .

11. Chip device according to any one of the preceding claims, wherein at least the chamber body (40) and the chip (20) are made by 3D printing.

12. Chip device according to any one of the preceding claims, comprising a control unit (70) for controlling the pressure generator (90) .

13. Chip device according to claim 12, wherein the control unit (70) is configured to selectively activateand deactivate the pressure generator according to a mechanical stimulation routine to be executed by the membrane (80) on the cellular structure.

14. Chip device according to claim 12 or 13, wherein the control unit (70) is configured to control the end position of the movement of the selected portion ( 80 ’ ) of the membrane (80) in the direction of the culture chamber (22) by adjusting the pressure built in the pressure chamber (42) by the pressure generator (90) .

15. Chip device according to any one of the preceding claims, wherein at least said chip is transparent .

16. Method for operating a chip device (10) according to any one of the preceding claims, comprising the steps of:- providing the chip (20) and depositing a cellular structure into the culture chamber (22) of the chip (20) ;- assembling the pressure generating system to the chip (20) having the cellular structure deposited into its culture chamber (22) , wherein assembling includes arranging the support element (60) with the membrane supported thereby (80) between the chip (20) and the chamber body (40) and by means of locking members (30) exerting locking forces pressing the chip (20) and the chamber body (40) against the outer region (64) of the support element (60) ; said method further including:- driving movement of the selected portion (80' ) of the membrane (80) by means of the pressure generator (90) to subject the cellular structure deposited into the culture chamber (22) , to a mechanical stimulation routine .

17. Method according to claim 16, wherein driving movement of the selected portion (80' ) of the membrane(80) includes controlling the end position of themovement of the selected portion (80' ) in the direction of the culture chamber (22) by adjusting the pressure built in the pressure chamber (42) by the pressure generator ( 90 ) .

18. Method according to claim 16 or 17, including: disassembling the pressure generating system from the chip (20) ; and extracting the cellular structure from the culture chamber (22) of the chip (20) .

19. Method according to any one of claims 16 to18, including adjusting the intensity of the mechanical stimulation exerted on the cellular structure.

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