Device for mechanically extracting stem cells

Abstract

The utility model relates to the technical field of regenerative medicine and cell therapy, in particular to a device for mechanically extracting stem cells, which comprises a hollow tube for storing tissues and a shearing plate provided with shearing holes, the shearing plate is arranged in the hollow tube and divides the hollow tube into a first chamber and a second chamber which are independent from each other, and the first chamber and the second chamber are communicated with each other. The first cavity and the second cavity are communicated through shearing holes in the shearing plate, a pushing mechanism used for organizing circulation between the first cavity and the second cavity is further arranged in the hollow pipe, two material pipes are arranged on the hollow pipe, the two material pipes are communicated with the first cavity and the second cavity respectively, and valves are arranged on the material pipes. The device for mechanically extracting the stem cells realizes homogenization treatment of tissues and efficient extraction of the stem cells through physical shearing, extrusion and bidirectional mechanical action, completely avoids time consumption of a traditional enzyme digestion method, reduces dependence on collagenase or other chemical reagents, and improves the extraction efficiency of the stem cells. The method is suitable for stem cell separation of tissues such as umbilical cord and fat with low damage and without allogenic material residue.

Description

Technical Field

[0001] This utility model relates to the field of regenerative medicine and cell therapy technology, and in particular to a device for mechanically extracting stem cells. Background Technology

[0002] Currently, enzymatic digestion methods, such as trypsin and collagenase, are commonly used to extract MSCs from tissues. While these methods are relatively efficient, they suffer from enzyme residue problems. They rely on collagenases (such as type I or type II) to break down the extracellular matrix (ECM), which is costly (enzyme dosage ≥0.1% w / v). Furthermore, enzymes may remain in the cell suspension after digestion, affecting subsequent cell culture and clinical applications. Enzymatic digestion can take 2-4 hours, and the enzymes may damage cell surface markers and cell membranes, reducing the functionality of MSCs. The enzyme transportation, storage, and handling involved in this technology all increase production costs and require strict aseptic and operational conditions.

[0003] Existing technologies also include examples of mechanical methods. CN114729296A uses a spiral flow generator and filter stack design to reduce the direct impact of adipose tissue on the filter wall, achieving mechanical separation through a multi-stage pore size filter; CN116240094A uses a converter combined with an adjustable flow gap converter tube and syringe to achieve fat emulsification and SVF separation through centrifugation and pushing; CN117987242B utilizes digestive beads and a rotating structure to achieve solid-liquid separation, combining a filter assembly and centrifugal layering to extract SVF cells, supporting washing and multiple centrifugation operations; C N204939466U filters connective tissue using a disposable plastic cap and filter membrane (pore size 80-120 microns) to retain SVF cell suspension; US20220135930A1 uses a progressively smaller mesh device to cut fat clumps, reducing cell damage, improving cell availability, and reducing the risk of operation in an incompletely sterile environment; CN217351313U uses metal balls in the extraction tube to achieve rapid and efficient separation of adipose vascular matrix components through mechanical movement (driven by protrusions and columns), with a compact design and easy operation.

[0004] However, in existing technologies, when extracting stem cells from tissues using mechanical methods, the extraction of stem cells is only carried out by physical shearing, centrifugation, and pushing or cutting. It has not been able to effectively combine physical shearing, squeezing and bidirectional mechanical action to homogenize the tissue from which stem cells are extracted, or there is still room for improvement in the extraction efficiency of stem cells. Therefore, we propose a device for extracting mesenchymal stem cells by purely mechanical methods. Utility Model Content

[0005] To address the problems of existing mechanical extraction devices being unable to homogenize materials and having low extraction efficiency, this invention provides a device for mechanically extracting stem cells. Through physical shearing, squeezing, and bidirectional mechanical action, it achieves homogenization of tissues and efficient extraction of stem cells, completely avoiding the time-consuming traditional enzymatic digestion method and reducing dependence on collagenase or other chemical reagents. It is suitable for the separation of stem cells from tissues such as umbilical cord and adipose tissue with low damage and no exogenous material residue.

[0006] This invention provides a device for mechanically extracting stem cells, comprising a hollow tube for storing tissue and a shearing plate with shearing holes. The shearing plate is disposed within the hollow tube and divides the hollow tube into independent first and second chambers, which are connected by the shearing holes on the shearing plate. The hollow tube also includes a pushing mechanism for tissue to flow between the first and second chambers. This method achieves homogenization of tissue and efficient extraction of stem cells through physical shearing, completely avoiding the time-consuming nature of traditional enzymatic digestion methods and dependence on collagenase or other chemical reagents.

[0007] Furthermore, the hollow tube is equipped with two feed pipes, which are connected to the first chamber and the second chamber respectively. The two feed pipes are set at a 90° angle and are equipped with valves. The feed pipes are used for feeding and discharging into the chambers, and the angled arrangement avoids mutual interference during feeding and discharging.

[0008] Furthermore, the pushing mechanism is provided in two sets, which are respectively located at both ends of the hollow tube and extend into the first and second chambers. Through the bidirectional mechanical action at both ends of the chambers, the tissue is subjected to mechanical shearing at the shear plate, breaking down large pieces of tissue into smaller particles.

[0009] Furthermore, the pushing mechanism includes a push rod and a push rod head. The push rod head is located at the end of the push rod and slides against the inner wall of the hollow tube via the push rod. The end of the hollow tube has a circular hole through which the push rod can extend. Mechanical action on the chamber is achieved through this simple push rod structure.

[0010] Furthermore, the end of the push rod extending from the hollow tube is provided with an end plate, and a spring is fitted onto the push rod between the end plate and the hollow tube. The spring facilitates the reset of the push rod.

[0011] Furthermore, a sealing gasket is provided on the side of the push rod head near the shear plate, and the sealing gasket has raised cross-shaped patterns. The sealing gasket enhances the seal between the push rod head and the hollow tube wall, and the cross-shaped patterns are used to compress the tissue onto the shear plate for appropriate grinding operations.

[0012] Furthermore, several limiting blocks are provided on the inner walls of the hollow tubes on both sides of the shearing plate, and these limiting blocks are evenly distributed circumferentially around the center of the shearing plate. The limiting blocks prevent the shearing plate from shifting and also limit the push rod from exerting excessive force on the shearing plate.

[0013] Furthermore, a pressure sensor is installed between the push rod and the push rod head, and the pressure sensor is electrically connected to an indicator light. This light is used to indicate whether the thrust is overloaded; if overloaded, a red warning light will illuminate.

[0014] Furthermore, the push rod includes a sleeve, a pull rod, and a push plate. The sleeve is connected to the push rod head and slides within the circular hole. The pull rod slides within the sleeve. One end of the pull rod is connected to the push plate, and the other end extends out of the sleeve and connects to the end plate. The push plate is slidably positioned within the sleeve via the pull rod. A second spring is provided between the push plate and the push rod head. The pull rod, push rod, and second spring constitute a simple spring pressure detection mechanism.

[0015] Furthermore, a pressure sensor is positioned between the pull rod and the push plate, an indicator light is mounted on the pressure sensor, and a transparent window is provided on the sleeve, opposite to the indicator light. The transparent window allows for easy and intuitive viewing of the thrust level.

[0016] The beneficial effects of this utility model are as follows:

[0017] This invention provides a device for mechanically extracting stem cells. It relies entirely on mechanical shearing, eliminating the need for any enzymes and avoiding enzyme residues and potential cell damage. The bidirectional shearing and multi-pore design ensures excellent tissue homogenization, resulting in highly active and pure extracted stem cells. It also reduces operating costs and process complexity. The disposable device and closed operating system minimize operational risks, making it suitable for various medical settings. A mechanical pressure display mechanism effectively prevents excessive cell shearing or blockage due to improper operation, improving extraction efficiency and safety. By replacing shear plates with different pore sizes, multi-stage shearing can be achieved for different tissues, meeting various tissue extraction needs and significantly shortening extraction time while improving cell viability. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the external structure of the extraction device;

[0020] Figure 2 This is a 3D view of the internal structure of the extraction device;

[0021] Figure 3 This is a plan view of the internal structure of the extraction device;

[0022] Figure 4 This is a schematic diagram of a pressure sensor;

[0023] In the diagram: 1. Hollow tube, 2. Shearing plate, 3. Material tube, 4. Push rod, 5. Push rod head, 6. End plate, 7. Spring 1, 8. Sealing gasket, 9. Cross pattern, 10. Limiting block, 11. Pressure sensor, 12. Indicator light, 13. Sleeve, 14. Pull rod, 15. Push plate, 16. Spring 2. Detailed Implementation

[0024] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0025] Traditional extraction of mesenchymal stem cells (MSCs) typically employs enzymatic digestion, a process that usually takes 2 to 3 hours, and even longer for difficult-to-digest tissues. To improve tissue processing time, avoid dependence on collagenases or other chemical reagents, and minimize the impact of enzyme residues on cell culture and subsequent applications, a mechanical MSC extraction device is designed, such as… Figure 1 As shown, the device includes a hollow tube 1 for storing tissue and a shearing plate 2 with shearing holes. The shearing plate 2 is disposed inside the hollow tube 1 and divides the hollow tube 1 into an independent first chamber and a second chamber. The first chamber and the second chamber are connected through the shearing holes on the shearing plate 2. The hollow tube 1 is also provided with a pushing mechanism for tissue to flow between the first chamber and the second chamber. There are two sets of pushing mechanisms, which are respectively disposed at both ends of the hollow tube 1 and extend into the first chamber and the second chamber.

[0026] The hollow tube 1 can be a single hollow pipe or two injection tubes joined together. When the hollow tube 1 is a hollow pipe, the shearing plate 2 is fixedly positioned in the middle of the hollow tube 1. When the hollow tube 1 is composed of two injection tubes joined together, the two injection tubes are fixedly connected to both ends of the shearing plate 2. The ends of the two injection tubes closest to the shearing plate 2 are open, allowing the two injection tubes to communicate with each other through the shearing plate 2. The pushing mechanism allows the tissue inside the first chamber and the second chamber to circulate with each other. The hollow tube 1 is preferably made of a transparent or semi-transparent material, allowing direct observation of the internal condition of the hollow tube 1. Volume markings can also be provided on the outer side of the hollow tube 1 to control the total tissue volume. The shearing plate 2 has a perforated sieve structure with a pore size of 40~1600um. When the tissue passes through the shearing holes, it will be subjected to shearing force. Different pore sizes can perform different shearing operations on the tissue, such as coarse shearing and fine shearing. The shearing plate 2 can be made of any one of rigid plastic, metal, or ceramic.

[0027] The preferred aperture of the shearing hole is 1200um, 800um, 300um, or 40um. The shearing plate 2 can be a shearing plate 2 with a special shape and specific aperture formed by laser or stamping on a thin stainless steel plate. Alternatively, it can be a mesh structure woven from fine, rigid metal wires or polymer material wires and then fixed to the outer ring as a solid circular shearing plate 2 through bonding and welding processes.

[0028] By using a pushing mechanism to perform physical shearing, squeezing, and bidirectional mechanical action, the homogenization of tissues and efficient extraction of stem cells are achieved. This completely avoids the time-consuming nature of traditional enzymatic digestion methods and the dependence on collagenase or other chemical reagents. It is suitable for the separation of stem cells from tissues such as umbilical cord and fat with minimal damage and no exogenous residue.

[0029] The hollow tube 1 is provided with two material tubes 3, which are respectively connected to the first chamber and the second chamber. The two material tubes 3 are arranged at least 90°, preferably 90°, so that when one material tube 3 opens downward to discharge material, the other material tube 3 is at least in a horizontal state, and the two material tubes 3 will not affect each other when in use.

[0030] The two feed pipes 3 are the injection port for pre-treated tissue and the outlet for tissue homogenate, respectively used for feeding pre-treated tissue and discharging treated tissue homogenate. At the same time, during multi-stage shearing, multiple hollow tubes 1 can be connected together in sequence through the feed pipes 3, so that the tissue homogenate processed in the previous stage can directly enter the interior of the next stage hollow tube 1.

[0031] The end of the feed tube 3 is connected to the external pipe or plug in either a threaded or bayonet manner to ensure a stable seal and connection when injecting tissue and extracting homogenized cell suspension. The end of the feed tube 3 is preferably a Luer threaded connector. The advantage of the threaded connector is that it ensures the reliability of the connection. Both feed tubes 3 are equipped with valves that can be closed after injecting or removing homogenate, or they contain automatic shut-off valves that open when the syringe is screwed in and automatically close after being screwed out.

[0032] like Figure 2 and 3 As shown, specifically, the pushing mechanism includes a push rod 4 and a push rod head 5. The push rod 4 has a push rod head 5 at its end, which slides against the inner wall of the hollow tube 1 via the push rod 4. The end of the push rod 4 extending out of the hollow tube 1 has an end plate 6, and a spring 7 is fitted onto the push rod 4 between the end plate 6 and the hollow tube 1. The spring 7 can apply a pushing force to the end plate 6, thereby easily driving the push rod head 5 to reset away from the shear plate 2.

[0033] A sealing gasket 8 is provided on the side of the pusher head 5 near the shear plate 2. The sealing gasket 8 has raised cross-shaped patterns 9, or other raised shapes such as rhombus or circle. The sealing gasket 8 is made of flexible medical material, such as EPDM or silicone, which are suitable for medical use. The sealing gasket 8 and the inner wall of the hollow tube 1 are press-fitted. When the sealing gasket 8 moves, it can push the tissue inside the tube. The surface of the sealing gasket 8 has fine texture, which can apply uniform shearing force to the tissue during mechanical advancement. The end of the hollow tube 1 has a round hole for the pusher 4 to extend. When dealing with tissues that are difficult to cut, the pusher 4 can be used to press the tissue onto the shear plate 2, and the pusher 4 can be rotated to use the cross-shaped patterns 9 to break up the tissue, thus performing appropriate grinding operations.

[0034] The hollow tubes 1 on both sides of the shear plate 2 are provided with a number of limiting blocks 10, which are evenly distributed circumferentially around the center of the shear plate 2. The shear plate 2 is limited from both sides to prevent displacement of the shear plate 2, and at the same time, it can also limit the push rod 4 from acting excessively on the shear plate 2.

[0035] like Figure 4 As shown, a pressure sensor 11 is installed between the push rod 4 and the push rod head 5. The pressure sensor 11 is electrically connected to an indicator light 12. The pressure sensor 11 is located between the pull rod 14 and the push plate 15. The indicator light 12 is installed on the pressure sensor 11. A transparent window is provided on the sleeve 13, opposite to the indicator light 12. This window is used to indicate the current pressure status and identify whether the thrust is overloaded. The indicator light 12 has three color segments: green, yellow, and red. When the transparent window displays red, the pushing speed should be reduced, or the large piece of tissue stuck in the shearing hole should be pushed back to avoid tissue blockage. This allows for bidirectional shearing, improving efficiency.

[0036] The push rod 4 can be a circular rod, or it can include a sleeve 13, a pull rod 14, and a push plate 15. The sleeve 13 is connected to the push rod head 5 and slides within the circular hole. The pull rod 14 is slidably engaged with the sleeve 13. One end of the pull rod 14 is connected to the push plate 15, and the other end extends out of the sleeve 13 and connects to the end plate 6. The push plate 15 is slidably positioned within the sleeve 13 via the pull rod 14. Rotating the pull rod 14 will cause the sleeve 13 to rotate as well. A second spring 16 is provided between the push plate 15 and the push rod head 5. The second spring 16 applies a pushing force to the push rod head 5, thereby easily resetting the push rod head 5 away from the shear plate 2. The pressure sensor 11 at the connection end measures the applied pressure in real time.

[0037] To simplify the structure, red and green sections can be directly marked on the pull rod 14 to replace the indicator light 12. Under normal pressure, the green section is displayed in the transparent window. If the thrust is too great, the red section will be pushed forward and displayed in the transparent window. Releasing the handle will cause it to retract.

[0038] The working principle of this mechanical stem cell extraction device is as follows: Tissue injection: One side tube 3 is opened, and the tissue to be processed (such as umbilical cord or adipose tissue) is injected into the hollow tube 1 through the other side tube 3. The push rod 4 is pushed to move the push rod head 5 to compress the air inside the hollow cavity 1, so that the air is discharged through the side tube 3. After the air in the cavity is emptied, the plugs on both side tubes 3 are closed, and the operation is carried out under aseptic conditions; Mechanical shearing: The bidirectional push rod 4 uses continuous reciprocating push-pull motion to subject the tissue to mechanical shearing action at the shear plate 2, breaking down large pieces of tissue into smaller particles; Pressure monitoring: During the shearing process, the pressure sensor 11 monitors the thrust in real time to ensure that the operation is within a safe range and to prevent cell damage due to overload; Homogenization and extraction: After continuous shearing, the resulting tissue homogenate is rich in stem cells. The cell suspension is then extracted through the side hole for subsequent purification steps such as centrifugation and filtration.

[0039] Example 1 (for umbilical cord tissue):

[0040] Step 1: Initial Injection and Coarse Shearing

[0041] First, Wharton's jelly (umbilical cord gel) is manually separated from the umbilical cord tissue and pre-injected into the hollow tube 1. If necessary, one side tube 3 can be opened and a shearing plate 2 with a built-in 800μm pore size can be used for preliminary shearing. After 20 rounds, the number of cells extracted is low, but the main task is to break up large pieces of tissue.

[0042] Step 2: Step-by-step fine cutting

[0043] The second stage of shearing was performed by replacing the shear plate with a 300μm pore size 2, and the process was repeated 10 times. Then, the third stage of shearing was performed by replacing the shear plate with a 40μm pore size 2, and the process was repeated 10 times. After the three-stage shearing, the number of extracted MSCs increased significantly, and the cell viability was high with no residual enzyme contamination.

[0044] Step 3: Cell suspension extraction

[0045] The homogenized tissue homogenate was extracted through the Luer connector on feed tube 3, and then purified by centrifugation and filtration to obtain a high-quality MSC suspension.

[0046] Example 2 (for adipose tissue):

[0047] Step 1: Tissue Injection and Preliminary Shearing

[0048] Adipose tissue was injected into hollow tube 1 and initially broken up using a large-aperture shear plate 2 (e.g., 800 μm) for 20 rounds.

[0049] Step 2: Multi-stage shearing process

[0050] The shearing plates 2 with medium and fine apertures (300μm and 40μm) are replaced in sequence, and repeated shearing operations are performed by bidirectional push rod 4, 10 times each. At the same time, the shearing pressure is monitored by pressure sensor 11 to ensure that the operation is within the safe range.

[0051] Step 3: Cell suspension collection

[0052] The homogenized tissue homogenate was collected using the small hole on the side wall of the hollow tube 1 or the feed tube 3, and then further purified after centrifugation.

[0053] The above description is illustrative only and not restrictive of this utility model. Those skilled in the art will understand that many modifications, variations or equivalents can be made without departing from the spirit and scope defined by the appended claims, and all such modifications, variations or equivalents will fall within the protection scope of this utility model.

Claims

1. A device for mechanical extraction of stem cells, characterized by: The utility model provides a hollow tube (1) and the shearing plate (2) of the shearing hole are arranged for depositing tissue, the shearing plate (2) is arranged in the hollow tube (1) and is separated into independent first chamber and second chamber, the first chamber and the second chamber are communicated through the shearing hole on the shearing plate (2), and the hollow tube (1) is also provided with the pushing mechanism for the tissue circulation between the first chamber and the second chamber.

2. A device for mechanical extraction of stem cells according to claim 1, characterized in that: Two material pipes (3) are arranged on the hollow tube (1), and the two material pipes (3) are communicated with the first chamber and the second chamber respectively, the two material pipes (3) are arranged at an angle of 90 DEG, and the material pipe (3) is provided with a valve.

3. The apparatus of claim 1, wherein: The pushing mechanism is provided with two groups, and the two groups of pushing mechanisms are arranged at two ends of the hollow tube (1) and extend into the first chamber and the second chamber.

4. A device for mechanical extraction of stem cells according to claim 3, characterized in that: The pushing mechanism includes a push rod (4) and a push rod head (5), the push rod head (5) is arranged at the end of the push rod (4), the push rod head (5) is slidably connected with the inner wall of the hollow tube (1) through the push rod (4), and the end of the hollow tube (1) is provided with a circular hole for the push rod (4) to extend out.

5. A device for mechanical extraction of stem cells according to claim 4, characterized in that: The end plate (6) is arranged at the end of the push rod (4) extending out of the hollow tube (1), a spring (7) is sleeved on the push rod (4) between the end plate (6) and the hollow tube (1).

6. The apparatus of claim 4, wherein: The side of the push rod head (5) close to the shearing plate (2) is provided with a sealing gasket (8), and the sealing gasket (8) is formed with a convex cross pattern (9).

7. The apparatus of claim 4, wherein: The inner wall of the hollow tube (1) on the two sides of the shearing plate (2) is provided with a plurality of limiting blocks (10) which are evenly distributed in the circumferential direction with the center of the shearing plate (2) as the center.

8. The apparatus of claim 5, wherein: A pressure sensor (11) is arranged between the push rod (4) and the push rod head (5), and the pressure sensor (11) is electrically connected with a prompt lamp (12).

9. A mechanical device for extracting stem cells according to claim 8, wherein: The push rod (4) includes a sleeve (13), a pull rod (14) and a push plate (15), the sleeve (13) is connected with the push rod head (5), the sleeve (13) is slidably arranged in the circular hole, the pull rod (14) is slidably connected with the sleeve (13), one end of the pull rod (14) is connected with the push plate (15), the other end of the pull rod (14) extends out of the sleeve (13) and is connected with the end plate (6), the push plate (15) is slidably arranged in the sleeve (13) through the pull rod (14), and a spring (16) is arranged between the push plate (15) and the push rod head (5).

10. A device for mechanical extraction of stem cells according to claim 9, characterized in that: The pressure sensor (11) is arranged between the pull rod (14) and the push plate (15), the prompt lamp (12) is arranged on the pressure sensor (11), a transparent window is arranged on the sleeve (13), and the transparent window is opposite to the prompt lamp (12).

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