Device and kit for measuring tension of cellular structures including muscle cells

Abstract

To provide a device and a kit for measuring tension in a cellular structure including muscle cells, which enable quantitative measurement of muscle contraction and are mass productive.SOLUTION: A device for measuring tension comprises: a first gel adapter holder comprising a first gel holding part for fixing one end of a gel; a second gel adapter holder comprising a second gel holding part provided opposite to the first gel holding part, for fixing the other end of the gel; and a fixing part capable of fixing a connecting member for connecting the first gel adapter holder and the second gel adapter holder.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a device and kit for measuring tension in cellular structures, including muscle cells. [Background technology]

[0002] In drug discovery research, in vitro tests using cultured cells and in vivo tests using laboratory animals are conducted to evaluate the safety and efficacy of developed drugs. For the former, in vitro culture systems of animal cells are used. For the latter, evaluation is carried out using systems using laboratory animals, mainly rodents.

[0003] In general, the success rate of drug discovery is said to be about 1 in 6,000, and the failure of numerous candidate drug developments has led to an increase in research and development costs for pharmaceutical companies and other organizations. It is generally said that an investment of tens of billions of yen is required to develop a single new drug. The main causes of failure in new drug development are said to be (1) differences between evaluation screening systems that use single cells and actual human biological tissue, and (2) differences between experimental animals and humans. Eliminating these differences, improving the success rate of drug discovery, and reducing research and development costs are required in the field of drug discovery and development.

[0004] In recent years, drug discovery screening methods have been developed that utilize pluripotent stem cells, such as iPS cells, which have the ability to differentiate into various functional cells. However, conventional evaluation systems use individual cells and do not reflect the state of living tissue. Therefore, there is a need to develop an evaluation system that mimics living tissue using somatic cells induced to differentiate from pluripotent stem cells.

[0005] Attempts to construct cells in three dimensions have been developed, for example, by seeding cells onto a three-dimensional structure called a scaffold, by decellularizing organs or tissues and seeding cells onto the remaining matrix to create a three-dimensional structure, and by stacking cell sheets exfoliated into sheets in a three-dimensional manner (e.g., Patent Document 1 and Non-Patent Document 1).

[0006] One method for producing cell sheets is to use a cell culture dish (temperature-responsive culture dish) coated with poly(N-isopropylacrylamide) (PIPAAm) (Patent Document 1). Any cells are cultured on the PIPAAm-coated temperature-responsive culture dish, and after the cells become confluent, the temperature is lowered to 20°C, which is lower than the lower critical solution temperature (LCST) of PIPAAm, 32°C, to non-invasively obtain a sheet-like cell (cell sheet).

[0007] Utilizing these technologies, research and development of evaluation systems for use in drug discovery screening is being conducted. As one evaluation system, attempts have been made to construct myocardial tissue to evaluate the cardiotoxicity of candidate drugs (e.g., Patent Documents 2 and 3). However, constructing an evaluation system using these methods is very complicated and not suitable for mass production. In addition, it is not possible to quantitatively measure muscle contraction.

[0008] There is a need for the development of a new evaluation system that can be used for drug discovery screening, particularly for cardiotoxicity screening tests, and that can be mass-produced and has a simple procedure. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 02-211865 [Patent Document 2] International Publication No. 2012 / 036224 [Patent Document 3] International Publication No. 2012 / 036225 [Non-patent literature]

[0010] [Non-Patent Document 1] Haraguchi Y.,et al.,Scaffold-free tissue engineering using cell sheet technology.RSC Adv.,2012;2:2184-2190 Summary of the Invention [Problem to be solved by the invention]

[0011] An object of the present invention is to provide a tension measurement device, system, and kit for measuring the tension of cellular structures including muscle cells, which are capable of quantitatively measuring muscle contraction and can be mass-produced. [Means for solving the problem]

[0012] The present inventors have conducted research and development, examining the above-mentioned problems from various angles. As a result, by devising the shape of a device for measuring tension in a cell structure containing muscle cells, they have developed the present invention, which enables quantitative measurement of muscle contraction and provides a mass-producible device, system, and kit for measuring tension in a cell structure containing muscle cells. Specifically, the present invention is as follows.

[0013] [1] A device for measuring tension of a cellular structure including muscle cells, a first gel adapter holder having a frame member and a first gel holding portion provided to protrude from a part of the inner surface of the frame member for fixing one end of a gel, wherein the frame member has a notch in an upper portion of the frame member at a position opposite to the first gel holding portion, thereby forming a pair of first gripping portions, and wherein the upper portion of the frame member has a pair of claw portions; and a second gel adapter holder having a second gel holding portion for fixing the other end of the gel and a connecting portion connected to the second gel holding portion via a connecting portion; Equipped with wherein the second gel adapter holder is attached to the first gel adapter holder by gripping the connecting portion with the first gripping portion so that the second gel holding portion faces the first gel holding portion inside the frame member; wherein the distance between the pair of first gripping portions is widened when the pair of claw portions are fitted with the culture medium vessel lid body. device.

[0014] [2] The device described in [1], wherein the muscle cells are at least one selected from the group consisting of cardiac muscle cells, skeletal muscle cells, and smooth muscle cells.

[0015] [3] The device described in [1] or [2], wherein the cell structure has at least one shape selected from the group consisting of a sheet shape, a rod shape, and a string shape.

[0016] [4] A device described in any one of [1] to [3], wherein the first gel holding portion has one or more first gel holding ports, and the second gel holding portion has one or more second gel holding ports.

[0017] [5] The device according to [4], wherein 2 to 5 of the first gel-retaining ports and 2 to 5 of the second gel-retaining ports are provided.

[0018] [6] The device according to any one of [1] to [5], wherein the thickness of the first gel holding portion and the second gel holding portion is thinner than the thickness of the frame member.

[0019] [7] The device according to any one of [1] to [6], wherein the thickness of the frame member is 0.5 mm to 3.0 mm.

[0020] [8] The device described in any one of [1] to [7], wherein the first gripping portion has a convex portion that protrudes in the direction of gripping the connecting portion, and the connecting portion has a concave portion into which the convex portion fits.

[0021] [9] The device described in any one of [1] to [8], wherein the frame member has a second gripping portion for gripping the second gel adapter holder.

[0022]

[10] The device according to any one of [1] to [9], wherein a gel is provided between the first gel holding portion and the second gel holding portion.

[0023]

[11] The device described in

[10] , wherein the gel is a hydrogel.

[0024]

[12] The device described in

[10] or

[11] , wherein the gel is a fibrin gel.

[0025]

[13] The device according to any one of

[10] to

[12] , comprising a cell structure containing muscle cells adhered to the gel.

[0026]

[14] The device described in

[13] , wherein the muscle cells are at least one selected from the group consisting of cardiac muscle cells, skeletal muscle cells, and smooth muscle cells.

[0027]

[15] The device described in

[13] or

[14] , wherein the cell structure has at least one shape selected from the group consisting of a sheet shape, a rod shape, and a string shape.

[0028]

[16] The device according to any one of

[13] to

[15] , wherein the cell structure is a cell sheet.

[0029]

[17] The device according to any one of

[13] to

[15] ; a medium tank body for immersing the device; a medium vessel lid for covering the medium vessel body, the medium vessel lid including a fitting portion that fits with the pair of claw portions and a connection portion through-hole through which the connection portion of the second gel adapter holder passes; a tension detection means connected to the connection portion of the second gel adapter holder; a computing unit connected to the tension detecting means for computing a signal detected by the tension detecting means to calculate the tension; and and an output means for displaying the result calculated by the calculator. A system for measuring tension in cellular structures, including muscle cells.

[0030]

[18] The system according to

[17] , wherein the tension detection means is a load cell.

[0031]

[19] A first gel adapter holder having a frame member and a first gel holding portion protruding from a portion of the inner surface of the frame member for fixing one end of a gel, wherein the frame member has a notch in the upper portion of the frame member at a position opposite to the first gel holding portion, thereby forming a pair of first gripping portions, and wherein the upper portion of the frame member has a pair of claw portions; a second gel adapter holder having a second gel holding portion for fixing the other end of the gel and a connecting portion connected to the second gel holding portion via a connecting portion; a substrate having a pair of gel-molded protrusions that fit along the inner surface of the frame member; and a gel-forming lid having a surface parallel to the gel contact surface of the base plate to form an upper surface of the gel; wherein the second gel adapter holder is attached to the first gel adapter holder by gripping the connecting portion with the first gripping portion so that the second gel holding portion faces the first gel holding portion inside the frame member; A kit for producing a device described in any one of [1] to

[15] , characterized in that the distance between the pair of first gripping portions widens when the pair of claw portions engage with the culture medium vessel lid.

[0032]

[20] The kit described in

[19] , wherein the first gel holding portion has one or more first gel holding ports, and the second gel holding portion has one or more second gel holding ports.

[0033]

[21] The kit according to

[19] or

[20] , wherein the thickness of the first gel holding portion and the second gel holding portion is thinner than the thickness of the frame member.

[0034]

[22] The kit according to any one of

[19] to

[21] , further comprising a gelling agent for producing the gel.

[0035]

[23] A device for measuring tension of a cellular structure including muscle cells, a first gel adapter holder having a first gel holding portion for fixing one end of the gel; a second gel adapter holder that fixes the other end of the gel and includes a second gel holding portion that is provided opposite the first gel holding portion; a fixing portion to which a connecting member for connecting the first gel adapter holder and the second gel adapter holder can be fixed.

[0036]

[24] The first gel adapter holder has a first fitting portion, The tension measuring device described in

[23] , further comprising a culture medium tank in which the first gel adapter holder and the second gel adapter holder are housed and which has a second fitting portion configured to be able to fit with the first fitting portion.

[0037]

[25] The tension measuring device according to

[23] or

[24] , wherein the fixing portion is provided on the first gel adapter holder and is engageable with the connecting member.

[0038]

[26] The device further includes a rod connecting the tension detection means and the second gel adapter holder, The second gel adapter holder further includes a first extension portion provided above the second gel holding portion and having a bullet-shaped cross section, the rod has a recess into which the first extension portion is inserted, The tension measuring device according to any one of

[23] to

[25] , wherein the second gel adapter holder and the rod are connected by inserting a fixing member into the first extension portion and the recess while the first extension portion is inserted into the recess.

[0039]

[27] The tension measuring device according to any one of

[23] to

[26] , wherein the second gel adapter holder has a pair of sleeves into which the connecting member is slidably inserted.

[0040]

[28] A kit for a tension measurement device for a cell structure including a muscle cell, comprising: a first gel adapter holder having a first gel holding portion for fixing one end of the gel; a second gel adapter holder that fixes the other end of the gel and includes a second gel holding portion that is provided opposite the first gel holding portion; a connecting member for connecting the first gel adapter holder and the second gel adapter holder; a substrate into which the first gel adapter holder and the second gel adapter holder connected by the connecting member are fitted; and a fixing portion to which the connecting member can be fixed.

[0041]

[29] The first gel adapter holder has a first fitting portion, The kit described in

[28] further comprises a culture medium vessel in which the first gel adapter holder and the second gel adapter holder are housed and which has a second fitting portion configured to be able to fit with the first fitting portion.

[0042]

[30] A rod connecting the tension detection means and the second gel adapter holder; The kit according to

[28] or

[29] , further comprising a rod holding jig that can be fixed to the top of the culture medium tank and has a rod holding portion that can hold the rod. [Effects of the Invention]

[0043] The present invention enables the simple measurement of tension in cellular structures containing muscle cells. Furthermore, the device of the present invention can be easily incorporated into a system for measuring tension in cellular structures containing muscle cells, enabling stable and reproducible data acquisition. [Brief explanation of the drawings]

[0044] [Figure 1] 1A to 1C are diagrams showing a tension measuring device according to a first embodiment, in which (A) is a front view, (B) is a side view, and (C) is a perspective view. [Figure 2] 2A to 2C are diagrams showing the first gel adapter holder of the tension measuring device of the first embodiment: (A) a front view, (B) a side view, and (C) a perspective view. [Figure 3]3A to 3C are diagrams showing the second gel adapter holder of the tension measuring device of the first embodiment: (A) a front view, (B) a side view, and (C) a perspective view. [Figure 4] 4A to 4C are diagrams showing a substrate used with the tension measuring device of the first embodiment: (A) a front view, (B) a side view, and (C) a perspective view. [Figure 5] 5A to 5C are diagrams showing a fixing member used with the tension measuring device of the first embodiment: (A) a front view, (B) a side view, and (C) a perspective view. [Figure 6] 6 is a diagram showing the combination of each of the components shown in FIGS. 2 to 5 with a gel-forming lid, (A) a front view, (B) a side view, and (C) a perspective view. [Figure 7] 7 is a diagram showing the steps of producing a tension measuring device using a kit for producing a tension measuring device of the first embodiment, (A) to (C): steps of producing a tension measuring device, (D): cross-sectional view of the tension measuring device obtained in (C). [Figure 8] FIG. 8 is a diagram showing a process for producing a tension measuring device according to the first embodiment. [Figure 9] 9A to 9D are diagrams showing how the tension measuring device is used in the first embodiment: (A) a plan view, (B) a perspective view, (C) a front view, and (D) a side view. [Figure 10] 10A and 10B are diagrams showing the tension measurement system of the first embodiment, (A) showing how the tension measurement system is used, and (B) showing the tension measurement device connected to the tension detection means connector. [Figure 11] FIG. 11 is a diagram showing a tension measurement system according to the first embodiment of the present invention. [Figure 12] 12 is a perspective view showing a tension measuring device of a comparative example: (A) a first gel adapter holder, (B) a second gel adapter holder, and (C) a combination of the first gel adapter holder, the second gel adapter holder, and the substrate. [Figure 13]Figure 13 shows the results of tension measurements (for 10 seconds) of human iPS cell-derived cardiomyocytes measured using the tension measurement device of the present invention. Note that for comparison, the tension values ​​are plotted on the same graph with the base tension value shifted. Top: Tension measurement results of cardiomyocytes detected using Adapter 1 (Comparative Example), Bottom: Tension measurement results of cardiomyocytes detected using Adapter 2 (the present invention). [Figure 14] Figure 14 shows the results of tension measurements (1200 seconds) of human iPS cell-derived cardiomyocytes measured using the tension measurement device of the present invention. Note that for comparison, the tension values ​​are plotted on the same graph with the base tension values ​​shifted. Top: Tension measurement results of cardiomyocytes detected using Adapter 1 (Comparative Example), Bottom: Tension measurement results of cardiomyocytes detected using Adapter 2 (the present invention). [Figure 15] Figure 15 shows the results of tension measurement of human iPS cell-derived cardiomyocytes measured using the tension measurement device of the present invention, and plots the results normalized by the average value of the results obtained in Figure 14. Upper row: tension measurement results of cardiomyocytes detected using adapter 1 (comparative example), lower row: adapter 2 (present invention). [Figure 16] FIG. 16 shows a state in which a cell structure containing rod-shaped human iPS cell-derived cardiomyocytes is applied to the tension measuring device of the present invention. [Figure 17] FIG. 17 is a perspective view showing a state in which a connecting member is connected to the tension measuring device of the second embodiment. [Figure 18] 18A and 18B are views showing a first gel adapter holder of a tension measuring device according to a second embodiment, in which (A) is a perspective view and (B) is a front view. [Figure 19] 19A and 19B are views showing a second gel adapter holder of a tension measuring device according to a second embodiment, in which (A) is a perspective view and (B) is a front view. [Figure 20] 20A and 20B are views showing the rod of the tension measuring device of the second embodiment, (A) a perspective view and (B) a front view. [Figure 21] FIG. 21 is a perspective view showing a pin of the tension measuring device of the second embodiment. [Figure 22]22A and 22B are diagrams showing the state in which the second gel adapter holder, the rod, and the pin of the tension measuring device of the second embodiment are assembled: (A) a perspective view, and (B) a side view. [Figure 23] 23A and 23B are diagrams showing a culture medium vessel of a tension measuring device according to a second embodiment: (A) a perspective view, and (B) a top view. [Figure 24] 24A and 24B are views showing a connecting member used with the tension measuring device of the second embodiment, (A) a perspective view and (B) a front view. [Figure 25] 25A and 25B are diagrams showing a base material used with the tension measuring device of the second embodiment, (A) a perspective view and (B) a front view. [Figure 26] FIG. 26 is a perspective view showing the first gel adapter holder and the second gel adapter holder connected by a connecting member. [Figure 27] FIG. 27 is a perspective view showing a state in which the first gel adapter holder and the second gel adapter holder connected by a connecting member are placed on a substrate, and a gel-forming lid is also placed thereon. [Figure 28] 28 shows a state in which the first gel adapter holder and the second gel adapter holder connected by a connecting member are fixed to a culture medium vessel: (A) perspective view, (B) cross-sectional view. [Figure 29] FIG. 29 is a perspective view showing a state in which the rod is held by the rod holding jig. [Figure 30] FIG. 30 is a perspective view showing a state in which the rear cover is attached to the culture vessel in the state shown in FIG. [Figure 31] 31 is a diagram showing a state in which the connecting member is removed from the state shown in FIG. 30, (A) a perspective view, (B) a cross-sectional view. [Figure 32] FIG. 32 is a perspective view showing a state in which the rod is connected to the tension detecting means from the state shown in FIG. [Figure 33] FIG. 33 is a perspective view showing the front cover. DETAILED DESCRIPTION OF THE INVENTION

[0045] First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to the drawings as necessary. The configuration of the embodiment is an example, and the configuration of the present invention is not limited to the specific configuration of the embodiment.

[0046] <Cellular structures containing muscle cells> As used herein, the term "cell structure containing muscle cells" refers to biological tissue containing muscle cells collected from a living organism (e.g., cardiac muscle tissue, skeletal muscle tissue, smooth muscle tissue, etc.) or a structure containing muscle cells. Cell structures containing muscle cells that can be applied to the present invention may be biological tissue collected from a living organism itself, or biological tissue processed from biological tissue collected from a living organism. Furthermore, cell structures containing muscle cells that can be applied to the present invention may be cell structures formed by mixing a suspension containing muscle cells with a gel solution or a gelling agent, or may be cell sheets. Furthermore, cell structures containing muscle cells that can be applied to the present invention may be those formed by directly seeding a group of cells containing muscle cells onto a gel and culturing them.

[0047] In one embodiment, the cell structure containing muscle cells that can be applied to the present invention may be at least one selected from the group consisting of a sheet-like, rod-like, and string-like shape, and is preferably a sheet-like cell structure.

[0048] As used herein, a "sheet-like cell structure" refers to a membrane-like cell structure having an average thickness of, for example, about 10 μm (e.g., the thickness of one cell) to about 2 mm, and a length that can be applied between the first gel holding section and the second gel holding section described below. The width of the "sheet-like cell structure" is not limited as long as it is a width that can be applied to the first gel holding section and the second gel holding section. One "sheet-like cell structure" may be applied to the tension measuring device, or multiple "sheet-like cell structures" may be applied to the tension measuring device. Multiple "sheet-like cell structures" may be applied in parallel between the first gel holding section and the second gel holding section, or may be applied in a stacked manner.

[0049] As used herein, "rod-shaped cell structures" refers to cell structures having an average diameter of, for example, about 100 μm or more and about 5 mm or less, and a length that can be applied between the first gel holding section and the second gel holding section described below. A single "rod-shaped cell structure" may be applied to the tension measurement device, or multiple "sheet-shaped cell structures" may be applied to the tension measurement device. Multiple "rod-shaped cell structures" may be applied in parallel between the first gel holding section and the second gel holding section, or may be applied bundled together.

[0050] In this specification, the term "string-like cell structure" refers to a three-dimensional cell structure having, for example, an average diameter of about 10 μm or more and less than about 100 μm, and a length that can be applied between the first gel holding section and the second gel holding section described below. One "string-like cell structure" may be applied to the tension measurement device, or multiple "string-like cell structures" may be applied to the tension measurement device. Multiple "string-like cell structures" may be applied in parallel between the first gel holding section and the second gel holding section, or may be applied bundled together.

[0051] Although "rod-shaped cell structures" and "string-shaped cell structures" are conveniently expressed as described above based on their diameter, both refer to cell structures with an elongated shape, and the terms may be used interchangeably.

[0052] The "rod-shaped cell structures" or "string-shaped cell structures" applicable to the present invention may be, for example, formed by forming a sheet-like cell structure into a rod or string shape (e.g., by winding, twisting, shrinking, or cutting), or may be formed by pouring a suspension containing cells and any gel into a rod-shaped or string-shaped mold (see, for example, Zhao Y, Cell. 2019 Feb 7;176(4):913-927).

[0053] As used herein, the term "cell structure containing muscle cells" refers to a cell structure in which at least 10% of the muscle cells contained therein are muscle cells, for example, 15% or more, 20% or more, 25% or more, 30% or more, 35% or more, 40% or more, 45% or more, 50% or more, 55% or more, 60% or more, 65% or more, 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, 95% or more, or 99% or more. As used herein, "muscle cells" refer to contractile cells that form muscle tissue in animals, including, for example, cardiac muscle cells, skeletal muscle cells, and smooth muscle cells. In one embodiment, the "muscle cells" used in the present invention are at least one selected from the group consisting of cardiac muscle cells, skeletal muscle cells, and smooth muscle cells. Muscle cells that can be used in the present invention may be derived from any animal, and muscle cells from mammals, birds, amphibians, reptiles, and fish can be used, for example. Preferably, the muscle cells are derived from mammals, such as mice, rats, humans, monkeys, pigs, dogs, sheep, cats, and goats.

[0054] The muscle cells that can be used in the present invention may be primary cells collected from biological tissue, established cell lines, or cells induced to differentiate from pluripotent stem cells or tissue stem cells.

[0055] As used herein, the term "pluripotent stem cells" is intended to collectively refer to stem cells that have the ability to differentiate into cells of any tissue (pluripotency). Pluripotent stem cells include, but are not limited to, embryonic stem cells (ES cells), embryonic carcinoma cells (EC cells), trophoblast stem cells (TS cells), epiblast stem cells (EpiS cells), embryonic germ cells (EG cells), multipotent germline stem cells (mGS cells), induced pluripotent stem cells (iPS cells), and Muse cells. ES cells or iPS cells are preferred. Any known pluripotent stem cells can be used, but for example, the pluripotent stem cells described in International Publication No. 2009 / 123349 (PCT / JP2009 / 057041) can be used.

[0056] Muscle cells that can be used in the present invention may be cells induced to differentiate from pluripotent stem cells. Methods for differentiating pluripotent cells into muscle cells can be known (see, for example, Matsuura K., et al., "Creation of human cardiac cell sheets using pluripotent stem cells." Biochem. Biophys. Res. Commun. 2012 Aug. 24; 425(2): 321-327).

[0057] The cell structure containing muscle cells may also contain cells other than muscle cells, such as cardiac myoblasts, myoblasts, mesenchymal stem cells, vascular endothelial cells, vascular endothelial progenitor cells, and fibroblasts.

[0058] As used herein, a "cell sheet," which is one embodiment of a "sheet-like cell structure," refers to a single-layer or multi-layer sheet-like cell population obtained by culturing a cell population containing a plurality of cells on a cell culture substrate and then detaching the cell population from the cell culture substrate. Methods for obtaining cell sheets include, for example, culturing cells on a stimuli-responsive culture substrate coated with a polymer whose molecular structure changes in response to stimuli such as temperature, pH, or light, and then altering the surface of the stimuli-responsive culture substrate by changing the stimuli such as temperature, pH, or light, thereby detaching the cells from the stimuli-responsive culture substrate in a sheet-like form while maintaining cell adhesion. Alternatively, cells may be cultured on a culture substrate and then physically detached using tweezers or the like. Known stimuli-responsive culture substrates for obtaining cell sheets include temperature-responsive culture substrates coated with a polymer whose hydration strength changes over a temperature range of 0 to 80°C. Cells are cultured on the temperature-responsive culture substrate at a temperature range where the hydration strength of the polymer is weak, and then the culture medium is changed to a temperature where the hydration strength of the polymer is strong, allowing the cells to be detached as a sheet-like cell population.

[0059] The temperature-responsive culture substrate used to obtain a cell sheet is preferably a substrate that changes its surface hydration power within a temperature range in which cells can be cultured. This temperature range is preferably the temperature at which cells are generally cultured, for example, 33°C to 40°C. The temperature-responsive polymer coated on the culture substrate used to obtain a cell sheet may be either a homopolymer or a copolymer. Examples of such polymers include the polymers described in JP-A-2-211865.

[0060] The use of poly(N-isopropylacrylamide) as a stimuli-responsive polymer, particularly a temperature-responsive polymer, will be described using an example (temperature-responsive culture dish). Poly(N-isopropylacrylamide) is known to have a lower critical dissolution temperature of 31°C. In its free state, it dehydrates in water at temperatures above 31°C, causing the polymer chains to aggregate and become cloudy. Conversely, at temperatures below 31°C, the polymer chains become hydrated and dissolved in water. In the present invention, this polymer is coated and immobilized on the surface of a substrate such as a petri dish. Therefore, at temperatures above 31°C, the polymer on the surface of the culture substrate also dehydrates, but because the polymer chains are immobilized on the surface, the surface of the culture substrate becomes hydrophobic. Conversely, at temperatures below 31°C, the polymer on the surface of the culture substrate becomes hydrated, but because the polymer chains are coated on the surface, the surface of the culture substrate becomes hydrophilic. A hydrophobic surface allows cells to attach and grow, while a hydrophilic surface prevents cells from attaching. Therefore, when the substrate is cooled to below 31°C, the cells detach from the substrate surface. If the cells are cultured to confluence over the entire culture surface, a cell sheet can be collected by cooling the substrate to below 31°C. The temperature-responsive culture substrate is not limited as long as it has the same effect, and examples include UpCell (registered trademark) available from CellSeed Inc. (Tokyo, Japan).

[0061] <Tension measuring device> The present invention provides a device for measuring tension of a cell structure including muscle cells, a first gel adapter holder having a frame member and a first gel holding portion provided to protrude from a part of the inner surface of the frame member for fixing one end of a gel, wherein the frame member has a notch in an upper portion of the frame member at a position opposite to the first gel holding portion, thereby forming a pair of first gripping portions, and wherein the upper portion of the frame member has a pair of claw portions; and a second gel adapter holder having a second gel holding portion for fixing the other end of the gel and a connecting portion connected to the second gel holding portion via a connecting portion; Equipped with wherein the second gel adapter holder is attached to the first gel adapter holder by gripping the connecting portion with the first gripping portion so that the second gel holding portion faces the first gel holding portion inside the frame member; Here, the device is characterized in that the distance between the pair of first gripping portions widens when the pair of claw portions are fitted with the culture medium vessel lid.

[0062] 1 to 6 show a tension measuring device 1 according to one embodiment of the present invention, as well as a fastener 15, a substrate 13, and a gel-forming lid 14 used with the tension measuring device 1. The tension measuring device 1 includes a first gel adapter holder 11 and a second gel adapter holder 12. The first gel adapter holder 11 includes a frame member 110 and a first gel retaining portion 111 provided by protruding from a portion of the inner surface of the frame member 110 (the bottom inner surface 119 in FIG. 1) for fixing one end of a gel G (described later). The frame member 110 is formed of a frame member lower portion 1110, frame member side portions 116 provided perpendicularly from both ends of the frame member lower portion 1110, and a frame member upper portion 114 provided at one end of the frame member side portion 116. In one embodiment, the frame member side portion 116 and the frame member upper portion 114 are thicker than the frame member lower portion 1110. The frame member 110 serves to serve as part of the mold when forming the gel G, and also serves to prevent any object from coming into contact with the gel G and the cell structure CS from the side. Furthermore, the presence of the frame member 110 makes it possible to easily attach the tension measuring device 1 to the culture medium vessel lid 21 (described below) of the culture medium vessel 2 while maintaining the shapes of the gel G and the cell structure CS.

[0063] A first gel non-forming space 1180 is provided between each side of the first gel holding portion 111 and the inner surface (side inner surface 118) of the frame member side portion 116. A gel molding convex portion 131 of the substrate 13, which will be described later, fits into the first gel non-forming space 1180.

[0064] The first gel holding portion 111 is provided in the lower portion 1110 of the frame member so as to be parallel to the thin film of gel G that is to be formed. The first gel holding portion 111 is provided with one or more first gel holding openings 112. First gel holding recesses 113 may further be provided on both ends of the first gel holding portion 111.

[0065] In this embodiment, the thickness of the gel G to be formed is determined by the thickness of the frame member lower part 1110 and the thickness of the second gel holding part connecting part 1210 (described below). Therefore, the thickness of the gel G can be appropriately changed by changing the thickness of the frame member lower part 1110 and the thickness of the second gel holding part connecting part 1210. The thicknesses of the frame member lower part 1110 and the second gel holding part connecting part 1210 are not limited, but may be any thickness that allows for adhesion and stable retention of a cell structure containing muscle cells and does not interfere with the pulsating contraction of the cell structure containing muscle cells. For example, the thickness is 0.5 mm to 3.0 mm, 0.5 mm to 2.5 mm, 0.5 mm to 2.0 mm, 0.5 mm to 1.5 mm, 1.0 mm to 3.0 mm, 1.0 mm to 2.5 mm, 1.0 mm to 2.0 mm, or 1.0 mm to 1.5 mm, preferably 0.5 mm to 2.5 mm, and more preferably 0.5 mm to 1.5 mm.

[0066] The thickness of the first gel holding portion 111 is configured to be thinner than the thickness of the frame member lower portion 1110 and the thickness of the second gel holding portion connecting portion 1210. The first gel holding portion 111 is provided at a middle position in the thickness direction of the frame member lower portion 1110 on the bottom inner surface 119. This allows the gel G to cover both the upper and lower surfaces of the first gel holding portion 111, and the gel G is reliably held.

[0067] The frame member 110 of the first gel adapter holder 11 has a notch 1143 in a part of the frame member 110 (frame member upper part 114) at a position facing the first gel holding part 111 (see FIG. 2(A)). The notch 1143 forms a pair of first gripping parts 1140 in the frame member upper part 114. The notch 1143 is provided along the axial direction in which the first gel holding part 111 and the second gel holding part 121 face each other. The width of the notch 1143 is adjusted appropriately depending on the width of the connecting part 124 of the second gel adapter holder 12 to be combined.

[0068] The pair of first gripping portions 1140 grip the connecting portion 124 of the second gel adapter holder 12. This attaches the second gel adapter holder 12 to the first gel adapter holder 11. The first gripping portions 1140 may further include a protrusion 1141 that protrudes in the direction of gripping the connecting portion 124. In this case, the connecting portion 124 of the second gel adapter holder 12 is provided with a recess 125 into which the protrusion 1141 fits. When the pair of first gripping portions 1140 grip the connecting portion 124 of the second gel adapter holder 12, the protrusion 1141 fits into the recess 125, preventing the second gel adapter holder 12 from falling off the first gel adapter holder 11. This prevents damage to the gel formed in the tension measuring device 1 and also facilitates handling of the tension measuring device 1 until the tension of a cellular structure containing muscle cells is measured.

[0069] In one embodiment, the upper frame member 114 of the first gel adapter holder 11 is provided with a pair of claws 117 sandwiching a notch 1143. The pair of claws 117 engage with the culture medium vessel lid 21 described below, and the tension measuring device 1 is fixed to the culture medium vessel lid 21. The pair of claws 117 are provided so that the distance between the pair of first gripping parts 1140 increases when the pair of claws 117 engage with the culture medium vessel lid 21 (see FIG. 9(C)). This forms a gap between the connecting part 124 of the second gel adapter holder 12 and the first gripping part 1140, reducing sliding between the connecting part 124 and the first gripping part 1140 and reducing variations in measurement values ​​resulting from sliding detected when measuring the tension of a cell structure including muscle cells. The shape and position of the pair of claws 117 may be any shape and position as long as a gap is formed between the connecting portion 124 and the first gripping portion 1140 when the pair of claws 117 is fitted to the culture medium vessel lid 21, and may be inclined toward the upper frame member 114, as shown in Fig. 2, for example. In one embodiment, the pair of claws 117 are inserted into the fitting portion 210 of the culture medium vessel lid 21 by being deformed by elasticity, and are fixed to the culture medium vessel lid 21 by returning to their original shape by the restoring force of the first gel adapter holder.

[0070] The upper outer surface 1144 (see FIG. 2(A)) of the frame member upper portion 114 of the first gel adapter holder 11 may be inclined toward the notch 1143. This allows the inclination of the upper outer surface 1144 to come into contact with the inner surface of the culture medium vessel lid 21 when the tension measuring device 1 is fixed to the culture medium vessel lid 21, forming a gap between the connecting portion 124 of the second gel adapter holder 12 and the first gripping portion 1140 (see FIG. 9(C)).

[0071] In one embodiment, the frame member 110 may further include a second gripping portion 1142 for gripping the second gel adapter holder 12 (see, for example, FIG. 1(A)). The second gripping portion 1142 may have a shape in which a portion of the frame member 110 is recessed inward to match the width of the second gel adapter holder 12, for example, the width of the second gel retaining portion connecting portion 1210 (see FIG. 1). This allows the second gel adapter holder 12 to be gripped and fixed by the second gripping portion 1142.

[0072] The material of the first gel adapter holder 11 is not particularly limited as long as it has the property of widening the gap between the pair of first gripping portions 1140 when the pair of claw portions 117 are engaged with the culture medium vessel lid 21, but examples include polyethylene, polypropylene, polycarbonate, polystyrene, polyvinyl chloride, nylon, polyurethane, polyurea, polylactic acid, polyglycolic acid, polyvinyl alcohol, polyvinyl acetate, poly(meth)acrylic acid, poly(meth)acrylic acid derivatives, polyacrylonitrile, poly(meth)acrylamide, poly(meth)acrylamide derivatives, polysulfone, cellulose, cellulose derivatives, polysilicone, and metal.

[0073] The second gel adapter holder 12 has a second gel holding portion 121 for fixing the other end of the gel G, and a connecting portion 120 connected to the second gel holding portion 121 via a connecting portion 124 (see FIG. 3). As shown in FIG. 3(A), in one embodiment, the connecting portion 120 and the second gel holding portion 121 are connected by the connecting portion 124 and a second gel holding portion connecting portion 1210. The second gel holding portion 121 is provided in the second gel holding portion connecting portion 1210 so as to be parallel to the gel G to be formed. The second gel holding portion 121 is provided with one or more second gel holding openings 122. Second gel holding recesses 123 are further provided on both ends of the second gel holding portion 121. The thickness of the second gel holding portion 121 is configured to be thinner than the thickness of the second gel holding portion connecting portion 1210, and preferably has the same thickness as the first gel holding portion 111. The second gel holding portion 121 is provided at a middle position in the thickness direction of the second gel holding portion connecting portion 1210. This allows the gel G to cover both the upper and lower surfaces of the second gel holding portion 121, and the gel G is reliably held.

[0074] In one embodiment, the connecting portion 124 may be provided with a recess 125 that fits into a protrusion 1141 provided on the first gripping portion 1140 of the first gel adapter holder 11 to prevent the second gel adapter holder 12 from falling off from the first gel adapter holder 11 (see FIG. 3). In particular, the recess 125 prevents the second gel adapter holder 12 shown in FIG. 3(A) from falling off from the first gel adapter holder 11 in the front-to-rear direction.

[0075] When the second gel adapter holder 12 is attached to the first gel adapter holder 11, the bottom of the connection portion 120 (connection portion lower portion 1200) comes into contact with the outer surface of the frame member upper portion 114, thereby limiting movement of the second gel adapter holder 12 toward the first gel holding portion 111 (hereinafter referred to as the "downward direction") and preventing damage to the gel. Similarly, the second gel holding portion connecting portion 1210 also comes into contact with the inner surface of the frame member upper portion 114, thereby limiting movement of the second gel adapter holder 12 in the direction opposite the first gel holding portion 111 (hereinafter referred to as the "upward direction") and preventing damage to the gel. The range of movement of the second gel adapter holder 12 in the upward and downward directions (hereinafter referred to as the "vertical direction") can be appropriately changed by adjusting the distance between the connection portion lower portion 1200 and the second gel holding portion connecting portion 1210.

[0076] The connection portion 120 is provided with a connection port 126 for connecting to the tension detection means connector 3 .

[0077] After the gel poured into the first gel holding port 112 and the second gel holding port 122 solidifies, it serves to fix one end of the gel G to the first gel holding portion 111 and the other end to the second gel holding portion 121. The first gel holding recess 113 and the second gel holding recess 123 also serve to fix the gel G after it solidifies. The number, shape, and size of the first gel holding port 112 and the second gel holding port 122 are appropriately determined depending on the size of the gel G to be produced, the viscosity, strength, degree of polymerization of the gel, and the like. The number of first gel holding ports 112 and the number of second gel holding ports 122 may be, for example, 1 to 10, 1 to 5, 2 to 5, or 2 to 4. The shapes of the first gel holding portion 111 and the second gel holding portion 121 are preferably symmetrical.

[0078] A substrate 13 and a gel-forming lid 14 are used to form a gel G in the tension measuring device 1 (see FIGS. 4 and 6). A pair of gel-forming protrusions 131 are provided on the flat surface 130 of the substrate 13, and the first gel holding portion 111 and the second gel holding portion 121 are fitted between the side inner surface 118. The substrate 13 also has a gel-forming protrusion upper portion 132 that fits into a second gel non-forming space 1112 formed between the first gel adapter holder 11 and the second gel adapter holder 12. This prevents gel from being formed in the second gel non-forming space 1112.

[0079] The width of the gel-forming lid 14 is approximately equal to the width of the inner surfaces of a pair of gel-forming convex portions 131 provided on the substrate 13. This allows the gel-forming lid 14 to fit between the pair of gel-forming convex portions 131. The length of the gel-forming lid 14 in this embodiment may be any length that covers the space in which the gel G is formed.

[0080] In one embodiment, the tension measuring device 1 of the present invention may include a fastener 15 shown in FIG. 5. The fastener 15 includes a fastener body 150 and fastener legs 151 provided substantially perpendicularly on both ends of the fastener body 150. The fastener 15 is attached so as to be hooked onto the outer sides of the pair of claws 117 (fastener attachment portions 1170) after the second gel adapter holder 12 is attached to the first gel adapter holder 11 (see FIG. 1). Attaching the fastener 15 applies inward pressure to the pair of first gripping portions 1140 of the frame member upper portion 114, thereby securely gripping the second gel adapter holder 12. The fastener 15 is removed, for example, when the tension measuring device 1 is attached to the culture medium vessel lid 21.

[0081] The materials for the second gel adapter holder 12, substrate 13, gel-forming lid 14, and fastener 15 are not particularly limited, but examples include polyethylene, polypropylene, polycarbonate, polystyrene, polyvinyl chloride, nylon, polyurethane, polyurea, polylactic acid, polyglycolic acid, polyvinyl alcohol, polyvinyl acetate, poly(meth)acrylic acid, poly(meth)acrylic acid derivatives, polyacrylonitrile, poly(meth)acrylamide, poly(meth)acrylamide derivatives, polysulfone, cellulose, cellulose derivatives, polysilicone, glass, ceramic, and metal.

[0082] <Kit for creating a tension measurement device for cell structures including muscle cells> The present invention provides a first gel adapter holder having a frame member and a first gel holding portion protruding from a part of the inner surface of the frame member for fixing one end of a gel, wherein the frame member has a notch in an upper portion thereof at a position opposite to the first gel holding portion, thereby forming a pair of first gripping portions, and wherein the upper portion of the frame member has a pair of claw portions; a second gel adapter holder having a second gel holding portion for fixing the other end of the gel and a connecting portion connected to the second gel holding portion via a connecting portion; a substrate having a pair of gel-molded protrusions that fit along the inner surface of the frame member; and a gel-forming lid having a surface parallel to the gel contact surface of the base plate to form an upper surface of the gel; wherein the second gel adapter holder is attached to the first gel adapter holder by gripping the connecting portion with the first gripping portion so that the second gel holding portion faces the first gel holding portion inside the frame member; Here, we provide a kit for producing a tension measuring device for cell structures including muscle cells, characterized in that the distance between the pair of first gripping portions widens when the pair of claw portions engage with the culture medium vessel lid.

[0083] The kit may also include a gelling agent to be formed between the first gel holding portion and the second gel holding portion. The gelling agent applicable to the present invention refers to a substance capable of forming a gel, and may be provided in the form of a solution or powder.

[0084] Gels that can be used in the present invention are those that (1) can adhere cell structures, including muscle cells, (2) are strong enough to maintain a sheet shape, and (3) do not adversely affect cell growth, functional expression, etc., i.e., are biocompatible. Examples of gels that can be used in the present invention include hydrogels. Examples of hydrogels that can be used in the present invention include hydrogels obtained by chemically crosslinking water-soluble, water-philic, or water-absorbent synthetic polymers, such as polyacrylamide, polyacrylic acid, polyhydroxyethyl methacrylate, polyvinyl alcohol, polylactic acid, and polyglycolic acid, as well as polysaccharides, proteins, and nucleic acids. Examples of polysaccharides include glycosaminoglycans such as hyaluronic acid and chondroitin sulfate, starch, glycogen, agarose, pectin, and cellulose. Examples of proteins include collagen and its hydrolyzed product, gelatin, proteoglycan, fibronectin, vitronectin, laminin, entactin, tenascin, thrombospondin, von Willebrand factor, osteopontin, and fibrinogen (for example, fibrin gel obtained by reacting fibrinogen with thrombin). These hydrogels may be crosslinked using known methods to increase their strength before use. A preferred gel applicable to the present invention is a fibrin gel. In one embodiment of the present invention, the gel may be formed by mixing it with cells in advance.

[0085] <Method of using the kit for preparing a tension measurement device for a cell structure containing muscle cells> 7 and 8, a method of using a kit for producing a tension measurement device for a cell structure including muscle cells in one embodiment will be described.

[0086] (i) The substrate 13 is set in the tension measurement device 1 (the first gel adapter holder 11 and the second gel adapter holder 12), and a pre-hardened gelling agent (e.g., a mixture of fibrinogen (SIGMA bovine plasma-derived Type IS), thrombin (SIGMA bovine plasma-derived T4648), CaCl2 solution (8 mM), and Factor XIII (CSL Behring Fibrogammin P for intravenous injection)) is injected into the gel formation region S using a pipette P (Figure 7(A)). At this time, the pre-hardened gel is injected while taking care not to let air get into the first gel holding port 112 and the second gel holding port 122.

[0087] (ii) After the injection, the gel-forming section S is covered with the gel-forming cover 14 (FIG. 7(B)).

[0088] (iii) After the gel has hardened, the gel-forming lid 14 and the substrate 13 are removed from the tension measuring device 1 (FIG. 7(C)).

[0089] (iv) Separately from the above, a group of cells including muscle cells is seeded onto a temperature-responsive culture dish D1 (e.g., UpCell (registered trademark) (CellSeed Inc., Tokyo, Japan)) and cultured at 37°C until the cells become confluent.

[0090] (v) The tension measuring device 1 provided with the gel obtained above is placed on the cell construct CS containing muscle cells in the temperature-responsive culture dish D1 (FIG. 7(C)).

[0091] (vi) Then, the temperature-responsive culture dish D1 is kept below the lower critical solution temperature, for example, 20°C, and the cell structure CS containing muscle cells is detached from the temperature-responsive culture dish D1, while at the same time, the cell structure CS containing muscle cells is adhered to the underside of the gel G (Figure 7(D)).

[0092] The cell structure CS containing muscle cells may be adhered in a single layer or in multiple layers to the gel G. To adhere a cell structure CS containing multiple layers of muscle cells, the above steps (v) and (vi) can be repeated any number of times.

[0093] It is preferable that the cell structure CS containing muscle cells has the same shape as the gel G before being attached to the gel G. Methods for forming the cell structure CS into the same shape as the gel G include, for example, cutting a cultured sheet-like cell group using a scalpel or the like, and seeding cells using a mold M that preliminarily limits the area where the cells will adhere to the shape of the gel G (see, for example, Figure 8(A)). By attaching the underside of the gel G to the cell structure CS containing muscle cells that has been formed into the shape of the gel G, the cell structure CS containing muscle cells can be easily attached to the gel G without contraction (see Figure 8(B)).

[0094] In another embodiment, a cell structure CS containing muscle cells may be formed by seeding a group of cells containing muscle cells directly onto the upper surface of the gel G formed in the above step (iii) and culturing them at 37°C until they become confluent or subconfluent. This allows for the production of a gel G to which a cell structure CS containing muscle cells is attached.

[0095] The tension measuring device 1 of the present invention may be provided by using the above-mentioned method, with gel G pre-formed between the first gel holding portion 111 and the second gel holding portion 121, and may also be provided with a cell structure CS including muscle cells adhered to the gel G.

[0096] <Tension measurement system for cell structures including muscle cells> The present invention also provides a tension measurement system for a cellular structure including muscle cells. The tension measurement system for a cellular structure including muscle cells includes, for example: (1) A first gel adapter holder having a frame member and a first gel holding portion provided to protrude from a part of the inner surface of the frame member for fixing one end of a gel, wherein the frame member has a notch in an upper portion of the frame member at a position opposite to the first gel holding portion, and a pair of first gripping portions formed thereby, wherein the upper portion of the frame member has a pair of claw portions; and a second gel adapter holder having a second gel holding portion for fixing the other end of the gel and a connecting portion connected to the second gel holding portion via a connecting portion; Equipped with wherein the second gel adapter holder is attached to the first gel adapter holder by gripping the connecting portion with the first gripping portion so that the second gel holding portion faces the first gel holding portion inside the frame member; Here, the device for measuring tension of a cell structure is characterized in that the distance between the pair of first gripping portions widens when the pair of claw portions are engaged with a culture medium vessel lid, and further comprises a gel between the first gel holding portion and the second gel holding portion, A cell structure including muscle cells adhered to the lower surface of the gel is provided. device; (2) A medium tank body in which the device of (1) is immersed; (3) a medium vessel lid for covering the medium vessel body, the medium vessel lid having a fitting portion that fits with the pair of claw portions and a connection portion through-hole through which the connection portion of the second gel adapter holder passes; (4) a tension detection means connected to the connection portion of the second gel adapter holder; (5) a computing unit connected to the tension detecting means, which computes the signal detected by the tension detecting means and calculates the tension; and (6) An output means for displaying the result calculated by the calculator.

[0097] The tension measuring device, which includes a gel and a cell structure containing muscle cells adhered to the gel, is housed in a culture medium vessel 2 (see FIG. 9). The culture medium vessel 2 is composed of a culture medium vessel body 20 and a culture medium vessel lid 21. The culture medium vessel lid 21 may be equipped with a culture medium supply line port 22 and a culture medium discharge line port 23, to which a culture medium supply line and a culture medium discharge line can be connected, respectively (not shown). This allows the culture medium in the culture medium vessel 2 to be replaced.

[0098] The culture medium vessel lid 21 is provided with a pair of fitting portions 210 into which the pair of claw portions 117 of the tension measuring device 1 are fitted. The fitting portions 210 may have any shape as long as they can be connected by the claw portions 117, and may be, for example, a through-hole as shown in FIG. 9(A), or a fitting means (not shown) may be provided on the inside of the culture medium vessel lid 21. The pair of fitting portions 210 are provided so that the distance between the pair of first gripping portions 1140 increases when the pair of fitting portions 210 are fitted with the pair of claw portions 117 (see FIG. 9(C)).

[0099] The culture medium vessel lid 21 is provided with a connection portion through-hole 211 through which the connection portion 120 of the second gel adapter holder 12 passes. The connection portion through-hole 211 has a shape that allows the connection portion 120 of the second gel adapter holder 12 to pass through.

[0100] The culture medium vessel lid 21 may further be provided with a sensor inlet 24. Any sensor (e.g., a pH sensor, a dissolved oxygen sensor, a temperature sensor, etc.) can be introduced through the sensor inlet 24. The culture medium vessel lid 21 may also be provided with a hook slide groove 212 so that the hook 31 of the tension detection means connector 3 (described later) can be easily guided into the connection port 126 of the second gel adapter holder 12 (see Figures 9(A) and (B)).

[0101] The hook 31 of the tension detection means connector 3 is passed through the connection port 126 of the second gel adapter holder 12, and the culture medium vessel 2 is installed in the culture system 4 (see FIG. 10). The culture medium vessel body 20 may be provided with a culture vessel recess that allows it to move along guide rails 42 to make it easier to install in the culture system 4.

[0102] The culture system 4 is provided with a tension detection means 40. The tension detection means connection part 32 of the tension detection means connector 3 is connected to the tension detection means 40. When the cell structure CS containing muscle cells contracts, the second gel adapter holder 12 is pulled downward, and the load is detected by the tension detection means 40 via the tension detection means connector 3. A known load cell, for example, can be used as the tension detection means 40. This makes it possible to measure the contractile force (tension) generated by the pulsation of the cell structure CS containing muscle cells. The tension detection means connector 3 only needs to have the function of connecting the second gel adapter holder 12 and the tension detection means 40, and may be a clamping means (not shown) in addition to the hook 31.

[0103] Although not shown, the culture medium vessel lid 21 may further be provided with a reagent supply port. By adding any desired drug through the reagent supply port, the effect of the drug on muscle cells can be investigated. The drug may be supplied to the culture medium vessel 2 by adding it to a culture medium reservoir tank (not shown) connected to a culture medium supply line. Although not shown here, the culture medium may be supplied to the culture medium vessel 2 by, for example, a tube pump, and the culture medium may be discharged by the tube pump.

[0104] The culture control unit 41 of the culture system 4 is equipped with a heater to maintain a constant temperature of the culture medium. It may also have a magnetic stirrer function, which allows the culture medium in the culture medium tank 2 to be stirred. The culture system 4 may also be provided with a hood (not shown) to prevent foreign matter from entering the culture medium tank 2.

[0105] 11 shows a tension measurement system 5 according to one embodiment of the present invention. Tension detection means 40 of culture system 4, in which tension measurement device 1 is set, is electrically connected to calculator 51 via cable 52. A signal detected by tension detection means 40 is input to calculator 51 via cable 52, and calculator 51 calculates the signal to calculate the tension. The calculated result is displayed by output means, such as a monitor, electrically connected to calculator 51. [Example]

[0106] The present invention will be described in more detail below with reference to examples, but these are not intended to limit the present invention. Example 1 1. Experimental Materials and Methods 1-1. Preparation of cardiomyocyte sheets Cardiomyocyte sheets containing iPS cell-derived cardiomyocytes were prepared according to the method of Matsuura et al. (Matsuura K., et al. Creation of human cardiac cell sheets using pluripotent stem cells. Biochem. Biophys. Res. Commun. 2012 Aug 24;425(2):321-327). 1-2.Tension measurement device The tension measuring device used was a tension measuring device (corresponding to the above-mentioned "tension measuring device 1") with a notch in the frame member of the first gel adapter holder. In Example 1, tension measuring device 1 made of biocompatible resin (MED610, Stratasys) was produced using a 3D printer (OBJET260 CONNEX3, Stratasys).

[0107] In addition, to verify the effect of the notch, a tension measuring device 1a (see FIG. 12) without a notch was used as a comparative example.

[0108] The basic configuration of the tension measuring device 1a (first gel adapter holder 11a, second gel adapter holder 12a) is the same as each component of the above-described tension measuring device 1. Except for the addition of "a" to the reference numeral of each component, the above-described explanations of the corresponding components of the above-described tension measuring device 1 apply to each component of the tension measuring device 1a. Here, we will briefly explain components to which the explanations of the components of the tension measuring device 1 do not apply.

[0109] The upper frame member 114a of the first gel adapter holder 11a has a first guide groove 1110a and a second guide groove 1111a, which limits the sliding direction of the second gel adapter holder 12a to the axial direction in which the first gel holding portion 111a and the second gel holding portion 121a face each other.

[0110] The second gel adapter holder 12a includes an L-shaped member 125a. The L-shaped member 125a is fitted into the first guide groove 1110a, and the second gel adapter holder body 127a is fitted into the second guide groove 1111a, thereby attaching the second gel adapter holder 12a to the first gel adapter holder 11a. Therefore, even when the tension measuring device 1a is in use, the second gel adapter holder 12a and the first gel adapter holder 11a always slide relative to each other.

[0111] 1-3. Measurement of tension in a sheet-like cell structure containing cardiomyocytes (cardiomyocyte sheet) The tension of a cell structure containing cardiomyocytes was measured using the tension measuring device 1 or the tension measuring device 1a of the comparative example in the following procedure (reference numerals are omitted).

[0112] (i) The substrate was set in the tension measurement device (first gel adapter holder and second gel adapter holder), and a pipette was used to inject pre-hardened gelling agent (a mixture of fibrinogen (SIGMA bovine plasma-derived Type IS), thrombin (SIGMA bovine plasma-derived T4648), CaCl2 solution (8 mM), and Factor XIII (CSL Behring Fibrogammin P for intravenous injection)) into the gel formation area.

[0113] (ii) After the injection, the gel-forming portion was covered with a gel-forming lid.

[0114] (iii) After the gel hardened, the gel-forming lid and the substrate were removed from the tension measurement device.

[0115] (iv) Separately from the above, a group of cells containing iPS cell-derived cardiomyocytes was seeded onto a temperature-responsive culture dish (UpCell (registered trademark) (CellSeed Inc., Tokyo, Japan)) and cultured at 37°C until confluent.

[0116] (v) A tension measuring device equipped with the gel obtained above was placed on the sheet-like cell structure containing cardiomyocytes.

[0117] (vi) Thereafter, the temperature-responsive culture dish was kept at 20°C, and a sheet-like cell structure containing cardiomyocytes (hereinafter referred to as cardiomyocyte sheet) was attached to the underside of the gel.

[0118] (vii) The tension measurement device with the cardiomyocyte sheet attached was immersed in myocardial culture medium (high-glucose Dulbecco's Modified Eagle's Medium (DMEM, Wako 043-30085) supplemented with 10% fetal bovine serum (FBS; Nichirei Biosciences), 500 KIU / ml aprotinin (Wako 016-11836), and 1% penicillin-streptomycin (Wako 161-23181)) and cultured at 37°C and 5% CO2 for one month.

[0119] (viii) Using a tension measurement device to which a cardiomyocyte sheet was attached, the tension measurement system shown in FIG. 10 was constructed, and tension measurements were performed.

[0120] 2.Results It was revealed that the cardiomyocyte cell sheet measured using the tension measuring device 1 of the present invention had smaller variations in tension per beat (stroke) (corresponding to the width of the band in Figures 13 and 14) compared to the tension measuring device 1a without a notch (Figure 15). <Example 2> A tension-measuring device with a cardiomyocyte cell sheet attached was obtained according to steps (i) to (vi) described in 1-3 of Example 1. A tension-measuring device 1 made of polypropylene was used. The tension-measuring device with the cardiomyocyte tissue attached was cultured in a myocardial culture medium for an extended period (one month or more) at 37°C under 5% CO2. As a result, rod-shaped cardiomyocyte tissues with a central diameter of approximately 100 to 200 μm were formed (Figure 16).

[0121] When the tension measurement system shown in Figure 10 was constructed using a tension measurement device equipped with rod-shaped cardiac muscle cell tissues, tension could be measured without any problems.

[0122] Second Embodiment Next, a second embodiment of the present invention will be described with reference to Figures 17 to 33. Explanation of parts common to the first embodiment will be omitted, and only features unique to the second embodiment will be described.

[0123] 17 to 33 show a tension measuring device 6 according to a second embodiment of the present invention, as well as a connecting member 66, a substrate 67, a gel-forming lid 68, a rod holding jig 69, a rear-side lid 70, and a front-side lid 71, which are used together with the tension measuring device 6.

[0124] 17 to 23, the tension measuring device 6 according to the second embodiment has a first gel adapter holder 61 that fixes one end of the gel, a second gel adapter holder 62 that fixes the other end of the gel, a rod 63 that connects the tension detecting means 40 and the second gel adapter holder 62, a fixing member (in this embodiment, for example, a pin 64) that connects the second gel adapter holder 62 and the rod 63, and a culture medium tank 65 that houses the first gel adapter holder 61 and the second gel adapter holder 62. Each component will be described in detail below.

[0125] As shown in Fig. 17, the first gel adapter holder 61 is disposed so as to be fixed to the culture medium tank 65. As shown in Figs. 17 and 18, the first gel adapter holder 61 has a first gel retaining portion 61A, a first fitting portion 61B, and a fixing portion 61C.

[0126] The first gel retaining portion 61A is disposed so as to face the second gel retaining portion 62A of the second gel adapter holder 62, which will be described later. The configuration of the first gel retaining portion 61A according to the second embodiment is the same as the configuration of the first gel retaining portion 111 according to the first embodiment described above, and therefore a description thereof will be omitted here.

[0127] The first fitting portion 61B is configured to fit into a second fitting portion 65B of the culture medium tank 65, which will be described later. As shown in Fig. 18, the first fitting portion 61B has a first protrusion 61E that protrudes vertically downward, and a second protrusion 61F that is provided below the first protrusion 61E and protrudes toward the front of the paper. Although not shown, a recess is formed on the rear side of the paper of the second protrusion 61F.

[0128] A pair of fixing portions 61C are provided on both left and right sides of the first gel retaining portion 61A. The fixing portions 61C are configured to be able to fix a connecting member 66 that connects the first gel adapter holder 61 and the second gel adapter holder 62. In the second embodiment, as shown in FIG. 18 , one fixing portion 61C is configured from a pair of elastically deformable elastic members 61G. The upper elastic member 61G has a wide portion 61H that widens upward, and the lower elastic member 61G has a wide portion 61H that widens downward. With the fixing portions 61C configured in this manner, when a second through-hole 66G of a connecting member 66 (described later) is inserted through the fixing portion 61C, the fixing portion 61C engages with the second through-hole 66G of the connecting member 66, thereby fixing the connecting member 66 to the first gel adapter holder 61.

[0129] As shown in Fig. 17, the second gel adapter holder 62 is disposed above the first gel adapter holder 61. As shown in Figs. 17 and 19, the second gel adapter holder 62 has a second gel retaining portion 62A, a first extending portion 62B, and a sleeve portion 62C.

[0130] The second gel holding portion 62A is disposed so as to face the first gel holding portion 61 A. The configuration of the second gel holding portion 62A according to the second embodiment is the same as the configuration of the second gel holding portion 121 according to the first embodiment described above, and therefore a description thereof will be omitted here.

[0131] The first extending portion 62B is provided at the upper end opposite to the second gel holding portion 62A. As shown in Fig. 19, the first extending portion 62B is configured to extend in the left-right direction together with the second gel holding portion 62A. The first extending portion 62B has a rectangular shape at the top and a circular shape at the bottom.

[0132] 19, the first extending portion 62B has a through hole 62H. A pin 64 is inserted through the through hole 62H. The diameter of the through hole 62H is configured to be slightly larger than the outer diameter of the pin 64.

[0133] 19, a pair of sleeves 62C are provided on the left and right sides. The sleeves 62C are provided to extend along the left-right direction. The sleeves 62C are inserted into first through-holes 66H of a connecting member 66, which will be described later.

[0134] As shown in FIG. 17, the rod 63 connects the tension detection means 40 and the second gel adapter holder 62. The rod 63 is disposed above the second gel adapter holder 62. The rod 63 according to the second embodiment corresponds to the tension detection means connector according to the first embodiment. As shown in FIG. 20, the rod 63 is configured to extend in the vertical direction. The rod 63 has an upper portion 63A provided above, a lower portion 63B provided below, and an intermediate portion 63C provided between the upper portion 63A and the lower portion 63B.

[0135] The middle portion 63C is provided with a constricted portion 63E that is constricted inward in the left-right direction. A rod holding portion 69D of a rod holding jig 69, which will be described later, is engaged with the constricted portion 63E. In this way, the rod holding jig 69 holds the rod 63.

[0136] 20, the lower portion 63B has a pair of half portions 63F provided on the left and right, a recess 63G, and a through-hole 63H. The recess 63G is provided at the rear of the upper surface of the half portion 63F. Furthermore, when viewed from the front, the through-hole 63H is provided between the pair of half portions 63F.

[0137] 22, the first extending portion 62B of the second gel adapter holder 62 is disposed in the recess 63G. The recess 63G is configured in a concave shape that follows the circular shape below the first extending portion 62B of the second gel adapter holder 62.

[0138] A pin 64 is inserted through the through hole 63H. The diameter of the through hole 63H is configured to be slightly larger than the outer diameter of the pin 64.

[0139] 17 and 22, the pin 64 is inserted into the through-hole 62H of the second gel adapter holder 62 and the through-hole 63H of the rod 63. As shown in Fig. 21, the pin 64 is configured with a gripping portion 64A that can be held. The user holds the gripping portion 64A and inserts the pin 64 into the through-hole 63H of the rod 63 and then into the through-hole 62H of the second gel adapter holder 62.

[0140] Specifically, as shown in Figure 22, with the first extension portion 62B of the second gel adapter holder 62 placed in the recess 63G of the rod 63, the pin 64 is inserted into the through hole 63H of the rod 63 and then into the through hole 62H of the second gel adapter holder 62, thereby connecting the second gel adapter holder 62 and the rod 63.

[0141] 17, a first gel adapter holder 61 is fixed to the culture medium vessel 65. The culture medium vessel 65 accommodates the first gel adapter holder 61, the second gel adapter holder 62, and the like.

[0142] 23, the culture medium vessel 65 has a cylindrical culture medium vessel main body 65A and a second fitting portion 65B configured to be able to fit with the first fitting portion 61B of the first gel adapter holder 61. The culture medium vessel main body 65A of the culture medium vessel 65 according to the second embodiment has substantially the same configuration as the culture medium vessel main body 20 of the culture medium vessel 2 according to the first embodiment described above, and therefore a description thereof will be omitted.

[0143] 17 and 23, the second fitting part 65B is integrally formed with the culture medium vessel main body 65A and is configured to protrude upward from the culture medium vessel main body 65A. As shown in Figures 17 and 23, the second fitting part 65B has a protruding part 65C that protrudes upward, and an inserted part 65D formed inside the protruding part 65C.

[0144] The inserted portion 65D has three protruding portions 65H that protrude inward from each other. By inserting the first fitting portion 61B into the inserted portion 65D of the second fitting portion 65B configured in this manner, the first protruding portion 61E of the first fitting portion 61B elastically deforms to fit the shape of the inserted portion 65D. The elastic force of this elastic deformation fixes the first gel adapter holder 61 to the culture medium tank 65.

[0145] The configuration of the tension measuring device 6 according to the second embodiment has been described above. Next, we will explain the configuration of a kit for the tension measuring device 6 that is used together with the tension measuring device 6. The kit for the tension measuring device 6 includes a connecting member 66, a substrate 67, a gel-forming lid 68, a rod holding jig 69, a rear-side lid 70, and a front-side lid 71.

[0146] To form the gel G in the tension measuring device 6, a connecting member 66, a substrate 67, and a gel-forming lid 68 are used (see FIGS. 24 to 27). Each component will be described below.

[0147] As shown in Fig. 17, the connecting member 66 connects the first gel adapter holder 61 and the second gel adapter holder 62. When measuring with the tension measuring device 6, the connecting member 66 is detached from the first gel adapter holder 61 and the second gel adapter holder 62. As shown in Figs. 17 and 24, a pair of connecting members 66 are provided on the left and right. The pair of connecting members 66 provided on the left and right are configured to be symmetrical along a vertical line.

[0148] 17 and 26, the configuration of the connecting member 66 provided on the left side of the pair of connecting members 66 will be described below. As shown in Fig. 24, the connecting member 66 has a second extending portion 66A extending in the vertical direction, a third extending portion 66B extending leftward from above the second extending portion 66A, a fourth extending portion 66C extending rightward from near the center of the second extending portion 66A in the vertical direction, and a fifth extending portion 66D extending downward from below the second extending portion 66A.

[0149] A first through-hole 66H is formed in the left-right direction on the inside of the fourth extending portion 66C. As shown in Figures 17 and 26, the sleeve portion 62C of the second gel adapter holder 62 is inserted into the first through-hole 66H.

[0150] A second through-hole 66G is formed in the fifth extending portion 66D along the left-right direction. As shown in Figures 17 and 26, the fixing portion 61C of the first gel adapter holder 61 is inserted into the second through-hole 66G, and the fixing portion 61C engages with the second through-hole 66G.

[0151] As shown in Fig. 27, the first gel adapter holder 61 and the second gel adapter holder 62 are placed on the substrate 67 while connected by a connecting member 66. As shown in Fig. 25, the substrate 67 has a plurality of protrusions 67H so that the first gel adapter holder 61 and the second gel adapter holder 62, while connected by the connecting member 66, can be placed on the substrate 67. The first gel adapter holder 61 and the second gel adapter holder 62, while connected by the connecting member 66, fit into recesses between the plurality of protrusions 67H. Note that the substrate 67 according to the second embodiment performs the same function as the substrate 13 according to the first embodiment, and therefore a detailed description of the configuration will be omitted.

[0152] The gel-forming lid 68 has the same configuration as the gel-forming lid 14 according to the first embodiment described above, and therefore a description thereof will be omitted.

[0153] Below, the method of using the kit will be explained, and the configurations of the rod holding jig 69, rear cover 70, and front cover 71 will also be explained.

[0154] The method for forming the gel and the method for obtaining the cell structure containing muscle cells are the same as those in the first embodiment, and therefore will not be described further. During gel formation, the first gel adapter holder 61 and the second gel adapter holder 62 are connected by a connecting member 66, as shown in FIG.

[0155] Next, with the first gel adapter holder 61 and the second gel adapter holder 62 connected by the connecting member 66, as shown in Fig. 28, the first gel adapter holder 61 and the second gel adapter holder 62 are lifted vertically to fix the first fitting portion 61B of the first gel adapter holder 61 to the second fitting portion 65B of the culture medium tank 65. At this time, because the first gel adapter holder 61 and the second gel adapter holder 62 are connected by the connecting member 66, the gel G to which the cell structure CS is adhered, which is disposed between the first gel adapter holder 61 and the second gel adapter holder 62, is prevented from being subjected to tensile force, and therefore damage to the cell structure CS can be prevented.

[0156] 29, a rod holding jig 69 is fixed to the culture medium vessel 65, and the rod 63 is held by the rod holding jig 69. The configuration of the rod holding jig 69 will be described below.

[0157] 29, the rod holding jig 69 has a flat portion 69A configured in a planar shape and a vertical wall portion 69B rising from the flat portion 69A. A pair of recesses 69C are formed in the flat portion 69A, in which protrusions 70B of the rear cover 70, which will be described later, are disposed. A rod holding portion 69D capable of holding a constricted portion 63E of the rod 63 is formed behind the vertical wall portion 69B. The rod holding portion 69D is inserted toward the constricted portion 63E until the rod 63 contacts the rod holding portion 69D, thereby supporting the constricted portion 63E and gripping the constricted portion 63E.

[0158] 30, the rear-side lid body 70 is fixed to the culture medium tank 65, and the protrusion 70B of the rear-side lid body 70 is inserted into the recess 69C of the rod holding jig 69. As shown in FIG. 30, the rear-side lid body 70 has a flat portion 70A configured in a flat shape and a protrusion 70B provided on an end of the flat portion 70A.

[0159] 31, the third extension portion 66B of the connecting member 66 protruding upward from between the rod holding jig 69 and the rear-side cover 70 is slid outward in the left-right direction (see the arrow in FIG. 30(A)), and the connecting member 66 is removed from the first gel adapter holder 61 and the second gel adapter holder 62. At this time, since the rod 63 is held by the rod holding portion 69D of the rod holding jig 69, even when the connecting member 66 is removed, the positions of the rod 63, the gel G to which the cell structure CS is adhered, etc. can be maintained.

[0160] Next, as shown in Figure 32, the rod 63 is connected to the tension detection means 40. At this time, even when the connecting member 66 is detached, the rod 63 can be held in a specified position by the rod holding jig 69, so the connection can be easily made by sliding the culture medium tank 65. Then, after connecting the rod 63 to the tension detection means 40, the rod holding jig 69 is removed, and the front lid 71 shown in Figure 33 is fixed in the same position as the rod holding jig 69 was attached.

[0161] As described above, the tension measuring device 6 according to the second embodiment is a device for measuring tension of a cell structure containing muscle cells. The tension measuring device 6 includes a first gel adapter holder 61 having a first gel holding portion 61A for fixing one end of a gel G and a first fitting portion 61B, a second gel adapter holder 62 having a second gel holding portion 62A for fixing the other end of the gel G and disposed opposite the first gel holding portion 61A, a culture medium vessel 65 that accommodates the first gel adapter holder 61 and the second gel adapter holder 62 and has a second fitting portion 65B configured to be able to fit with the first fitting portion 61B, and a fixing portion 61C to which a connecting member 66 for connecting the first gel adapter holder 61 and the second gel adapter holder 62 can be fixed. The tension measuring device 6 configured in this manner allows for easy measurement of the tension of a cell structure containing muscle cells.

[0162] Furthermore, fixing portion 61C is provided on first gel adapter holder 61 and is engageable with connecting member 66. With this configuration, connecting member 66 can be reliably fixed to first gel adapter holder 61 and second gel adapter holder 62.

[0163] The tension measuring device 6 also has a rod 63 that connects the tension detection means 40 and the second gel adapter holder 62. The second gel adapter holder 62 further has a first extension portion 62B provided above the second gel retaining portion 62A, and the rod 63 has a recess 63G into which the first extension portion 62B is inserted. With the first extension portion 62B inserted into the recess 63G, the second gel adapter holder 62 and the rod 63 are connected by inserting a pin 64 into the first extension portion 62B and the recess 63G. With this configuration, the rod 63 and the second gel adapter holder 62 are in surface contact and are fixed to each other by the pin 64, so that the rod 63 and the second gel adapter holder 62 can be suitably restrained.

[0164] The second gel adapter holder 62 also has a pair of sleeves 62C into which the connecting member 66 is slidably inserted. With this configuration, the connecting member 66 can be easily removed from the first gel adapter holder 61 and the second gel adapter holder 62.

[0165] Furthermore, the kit for the tension measuring device 6 according to the second embodiment includes a first gel adapter holder 61 having a first gel holding portion 61A for fixing one end of the gel G and a first fitting portion 61B, a second gel adapter holder 62 having a second gel holding portion 62A for fixing the other end of the gel G and arranged opposite the first gel holding portion 61A, a culture medium tank 65 that accommodates the first gel adapter holder 61 and the second gel adapter holder 62 and has a second fitting portion 65B configured to be able to fit with the first fitting portion 61B, a connecting member 66 for connecting the first gel adapter holder 61 and the second gel adapter holder 62, a base plate 67 on which the first gel adapter holder 61 and the second gel adapter holder 62 connected by the connecting member 66 fit, and a fixing portion 61C to which the connecting member 66 can be fixed. With the kit configured in this manner, when the first gel adapter holder 61 and the second gel adapter holder 62 are lifted vertically and the first fitting portion 61B of the first gel adapter holder 61 is fixed to the second fitting portion 65B of the culture medium tank 65, the gel G to which the cell structure CS is adhered can be suitably prevented from being subjected to tensile force, thereby suitably preventing damage to the cell structure CS.

[0166] The kit also includes a rod 63 that connects the tension detection means 40 and the second gel adapter holder 62, and a rod holding jig 69 that can be fixed to the top of the culture medium tank 65 and has a rod holding part 69D that can hold the rod 63. With a kit configured in this manner, even if the connecting member 66 is removed, the positions of the rod 63, the gel G to which the cell structure CS is adhered, etc. can be maintained.

[0167] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims.

[0168] For example, in the second embodiment described above, the fixing portion 61C is provided on the first gel adapter holder 61. However, the fixing portion may be provided at any location as long as the connecting member 66 can be fixed thereto, and the shape thereof is not limited. Furthermore, the wide portion 61H provided on the pair of elastically deformable elastic members 61G of the fixing portion 61C may be provided on at least one of the upper and lower elastic members 61G.

[0169] Furthermore, in the second embodiment described above, the second gel adapter holder 62 and the rod 63 are connected together by fastening them together with the pin 64, with the first extension portion 62B of the second gel adapter holder 62 inserted into the recess 63G of the rod 63. However, the means for connecting the second gel adapter holder 62 and the rod 63 is not limited to the above configuration.

[0170] Furthermore, in the second embodiment described above, the first gel adapter holder is provided with a first fitting portion 61B, and by inserting the first fitting portion 61B into the inserted portion 65D of the second fitting portion 65B, the first protrusion 61E of the first fitting portion 61B matches the shape of the inserted portion 65D, and the first gel adapter holder 61 is fixed to the culture medium tank 65. However, this is not limited to this as long as the first gel adapter and the second gel adapter can be fixed, and for example, the first fitting portion 61B of the first gel adapter holder and the inserted portion 65D of the second fitting portion 65B may be configured in an interchangeable manner, or they may be provided in any other location, and furthermore, their shape is not limited to the above configuration. [Explanation of symbols]

[0171] 1, 1a, 6 Tension measuring device 11, 11a, 61 First gel adapter holder 110, 110a frame members 111, 111a, 61A First gel holder 1110 Lower frame member 112, 112a First gel holding port 113, 113a First gel holding recess 114, 114a Upper part of frame member 1140 1st grip part 1141 convex part 1142 Second grip part 1143 Cutout 1144 Upper outer surface 115, 115a upper inner surface 116, 116a frame member side 1160, 1160a Slope 117, 117a Claw part 1170 Fastener attachment part 118, 118a inner side surface 1180 First gel-free space 119, 119a Bottom inner surface 1110a First guide groove 1111a Second guide groove 1112 Second gel-free space 12, 12a Second gel adapter holder 120, 120a connection 1200 Lower connection 121, 121a, 62A Second gel holder 1210 Second gel holder connection part 122, 122a Second gel holding port 123, 123a Second gel holding recess 124 Connection section 125 recess 125a L-shaped member 126, 126a connection ports 127a Second gel adapter holder body 128a Stopper opening 13, 67 board 130 Plane section 131 Gel molding convex part 132 Upper part of gel-forming convex part 133 L-shaped fitting groove 134 Top of the board 14 Gel-forming lid 140 Gel-forming lid gripping part 15 Fasteners 150 Fastener body 151 Fastener leg 2, 65 Culture medium tank 20, 65A Culture medium tank body 200 Culture tank recess 21 Culture medium tank lid 210 Fitting part 211 Connection through-hole 212 Hook slide groove 22 Medium supply line port 23 Medium discharge line outlet 24 Sensor inlet 3 Tension detection means connector 31 Hook 32 Tension detection means connection part 4. Culture System 40 Tension detection means 41 Culture control unit 42 Guide rail 5. Tension measurement system 51 Arithmetic unit 52 Cable S Gel forming part C cell CS cell structure P pipette G Sheet gel D1, D2 culture dish M mold MS cell inlet G+CS gel + cell structure 61B First fitting part 61C Fixed part 62B 1st extension part 63 Rod 63G recess 64-pin 65B 2nd fitting part 66 Connecting member 69 Rod holding jig 69D Rod holder

Claims

1. A device for measuring tension of a cellular structure including muscle cells, a first gel adapter holder having a first gel holding portion for fixing one end of the gel; a second gel adapter holder for fixing the other end of the gel and including a second gel holding portion provided opposite to the first gel holding portion; a fixing portion to which a connecting member for connecting the first gel adapter holder and the second gel adapter holder can be fixed, The fixing portion is provided on the first gel adapter holder and is a tension measuring device that is removably engageable with the connecting member.

2. the first gel adapter holder has a first fitting portion, The tension measuring device according to claim 1, further comprising a culture medium tank in which the first gel adapter holder and the second gel adapter holder are housed and which has a second fitting portion configured to be able to fit with the first fitting portion.

3. a rod connecting the tension detecting means and the second gel adapter holder; the second gel adapter holder further includes a first extension portion provided above the second gel holding portion, the rod has a recess into which the first extension portion is inserted, 3. The tension measuring device according to claim 1, wherein the second gel adapter holder and the rod are connected by inserting a fixing member into the first extension portion and the recess with the first extension portion inserted into the recess.

4. 4. The tension measuring device according to claim 1, wherein the second gel adapter holder has a pair of sleeves into which the connecting member is slidably inserted.

5. A kit for a device for measuring tension of a cell structure including a muscle cell, comprising: a first gel adapter holder having a first gel holding portion for fixing one end of the gel; a second gel adapter holder for fixing the other end of the gel and including a second gel holding portion provided opposite to the first gel holding portion; a connecting member for connecting the first gel adapter holder and the second gel adapter holder; a substrate into which the first gel adapter holder and the second gel adapter holder connected by the connecting member are fitted; a fixing portion to which the connecting member can be fixed, The fixing portion is provided on the first gel adapter holder and is removably engageable with the connecting member.

6. the first gel adapter holder includes a first fitting portion; The kit according to claim 5 , further comprising a culture medium vessel in which the first gel adapter holder and the second gel adapter holder are housed and which has a second fitting portion configured to be able to fit with the first fitting portion.

7. a rod connecting the tension detecting means and the second gel adapter holder; The kit according to claim 5 or 6, further comprising a rod holding jig that can be fixed to the top of the culture medium vessel and that has a rod holding portion that can hold the rod.

8. A device for measuring tension of a cell structure including muscle cells, comprising: a first gel adapter holder having a first gel holding portion for fixing one end of the gel; a second gel adapter holder for fixing the other end of the gel and including a second gel holding portion provided opposite to the first gel holding portion; a fixing portion to which a connecting member for connecting the first gel adapter holder and the second gel adapter holder can be fixed, the fixing portion is provided on the first gel adapter holder and is removably engageable with the connecting member, The second gel adapter holder is a tension measuring device having a pair of sleeves into which the connecting member is slidably inserted.

Images