Filter device for removing blood cancer cells by combining antibody modified filter membrane

Abstract

The invention discloses a filtering device for removing blood cancer cells by combining an antibody modified filter membrane, the filtering device comprises a device main body, two ends of the device main body are respectively provided with a liquid inlet and a liquid outlet, the inside of the device main body is sequentially provided with a first-stage pre-filtering membrane, a second-stage targeting membrane and a third-stage fine filtering membrane from the liquid inlet to the liquid outlet, and the first-stage pre-filtering membrane, the second-stage targeting membrane and the third-stage fine filtering membrane are arranged in the device main body. A liquid homogenizing and shunting part is arranged between the primary pre-filtration membrane and the liquid outlet, the secondary targeting membrane comprises at least one antibody modification plate, axially through micropores are uniformly distributed in the antibody modification plate, and a surface covalent coupling EpCAM antibody, a CK antibody and a PD-L antibody are arranged on the inner side wall of each micropore. The problem that an existing single filtering technology cannot meet the requirement for blood safety of autologous blood transfusion in a tumor patient operation can be solved.

Description

Technical Field

[0001] This invention relates to the field of medical blood purification technology, specifically to a filtration device that combines an antibody-modified filter membrane to remove blood cancer cells. Background Technology

[0002] In the surgical treatment of cancer patients, intraoperative autologous blood transfusion technology has been applied to a certain extent in the clinical field due to its advantage of effectively reducing the risks of infection and immune rejection that may be caused by allogeneic blood transfusion, providing important support for ensuring blood safety during surgery.

[0003] However, this technology faces a key bottleneck in practical applications: if circulating tumor cells (CTCs) remain in the reinfused blood, these CTCs will re-enter the patient's body with the blood, thereby significantly increasing the risk of tumor metastasis. This problem severely restricts the safe application of intraoperative autologous blood reinfusion technology for cancer patients.

[0004] Currently, existing technologies for clearing CTCs from blood mostly rely on single filtration methods, among which physical sieving (such as pore size filtration) is a commonly used approach. However, this type of physical sieving technology has significant limitations; it is insufficient in capturing interstitial CTCs with a diameter of less than 10 μm, making it difficult to effectively remove these CTCs with high metastatic potential.

[0005] Since traditional single filtration technology cannot meet the core requirements of blood safety for autologous blood transfusion during surgery in cancer patients, there is an urgent clinical need for a technical solution that can efficiently remove various CTCs in the blood while ensuring the activity of red blood cells, thereby providing a safety guarantee for autologous blood transfusion in cancer patients. Summary of the Invention

[0006] This invention provides a filtration device that combines antibody-modified filter membranes to remove blood cancer cells, which can solve the problem that existing single filtration technologies cannot meet the safety requirements of autologous blood reinfusion during surgery for cancer patients.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a filtration device for clearing blood cancer cells using an antibody-modified filter membrane, comprising a device body, with an inlet and an outlet respectively provided at both ends of the device body; a primary pre-filtration membrane, a secondary targeting membrane, and a tertiary fine filtration membrane sequentially installed inside the device body from the inlet to the outlet; a liquid equalization and diversion component provided between the primary pre-filtration membrane and the outlet; the secondary targeting membrane comprising at least one antibody-modified plate, wherein axially penetrating micropores are evenly distributed on the antibody-modified plate, and a surface coating is provided on the inner wall of the micropores. The system covalently conjugates EpCAM, CK, and PD-L antibodies. A primary pre-filtration membrane mechanically filters and intercepts impurities larger than 100 μm in the blood (such as tissue debris and fibrin clots). A secondary targeting membrane with a microporous structure prolongs the contact time with cancer cells and improves the capture rate. The surface-covalently conjugated EpCAM antibody captures epithelial-derived CTCs, the CK antibody recognizes cytokeratin, and the PD-L antibody covers cancer cells that highly express immune checkpoints, thus forming a multi-target capture network. A tertiary fine filtration membrane removes residual debris, achieving long-term anti-clogging.

[0008] Preferably, the primary pre-filtration membrane includes a polyester filter and a heparin-albumin complex layer coated on the upper side of the polyester filter, which can inhibit platelet activation and initial coagulation.

[0009] Preferably, the upper end of the liquid equalization and diversion component is connected to the liquid inlet, and the lower end is abutted against the primary pre-filtration membrane. The liquid equalization and diversion component has obliquely arranged diversion channels evenly distributed inside. The liquid equalization and diversion component can guide blood cells to pass through evenly and reduce the risk of local blockage.

[0010] Preferably, the antibody modification plates are at least two arranged axially, with adjacent antibody modification plates close together and the micropores corresponding to each other and connected, which can form multiple capture paths and ensure the capture rate.

[0011] Preferably, the surface covalently coupled EpCAM antibody, CK antibody, and PD-L antibody are arranged in micropillars and arrayed on the inner sidewall of the micropores. The micropillars can prolong the contact time with cancer cells and improve the capture rate.

[0012] Preferably, the three-stage fine filtration membrane includes a fine filtration membrane and a hydrated molecular layer coated on the surface of the fine filtration membrane. The hydrated molecular layer can reduce protein adsorption and cell adhesion, thereby reducing the clogging rate.

[0013] Preferably, the main body of the device includes a central column, a liquid inlet end seat and a liquid outlet end seat that are detachably disposed at both ends of the central column. The liquid inlet is installed on the liquid inlet end seat and the liquid outlet is installed on the liquid outlet end seat. The overall size is small, and it is easy to disassemble and assemble, which facilitates the installation of the internal primary pre-filtration membrane, secondary targeted membrane and tertiary fine filtration membrane.

[0014] Preferably, the secondary targeting membrane is disposed in the middle of the central column, the primary pre-filtration membrane is installed between one end of the central column and the inlet end seat, and the tertiary fine filtration membrane is disposed between the other end of the central column and the outlet end seat. The primary pre-filtration membrane and the tertiary fine filtration membrane are positioned by utilizing the connection relationship between the central column, the inlet end seat and the outlet end seat, without the need for other connecting structures.

[0015] Preferably, one end of the central column is provided with a connecting step portion, the primary pre-filtration membrane abuts axially against the connecting step portion, and the liquid inlet end seat is threadedly connected to the outer side of the connecting step portion. The connecting step portion can improve the connection strength between the central column and the liquid inlet end seat, and at the same time, the connecting step portion can axially limit the primary pre-filtration membrane.

[0016] Preferably, one end of the liquid outlet seat is provided with a connecting part that extends into the central column for threaded connection, and the three-stage fine filtration membrane abuts axially against the connecting part.

[0017] Compared with the prior art, the beneficial effects of the present invention are: With its simple structure and small overall size, it is convenient to carry and place. The first-stage pre-filtration membrane can mechanically screen and intercept impurities >100μm in the blood. The second-stage targeting membrane uses a microporous structure to prolong the contact time with cancer cells and improve the capture rate. The surface covalently coupled EpCAM antibody can capture epithelial-derived CTCs, the CK antibody can recognize cytokeratin, and the PD-L1 antibody can cover cancer cells that highly express immune checkpoints, thus forming a multi-target capture network. The third-stage fine filtration membrane can remove residual debris and achieve long-term anti-clogging. It solves the problem that existing single filtration technologies cannot meet the blood safety requirements of autologous blood reinfusion during surgery for cancer patients. Attached Figure Description

[0018] Figure 1 This is a front sectional view of the structure according to the present invention; Figure 2 yes Figure 1 Enlarged structural diagram at point A; Figure 3 yes Figure 1 Enlarged structural diagram at point B; Figure 4 yes Figure 1 Enlarged structural diagram at point C.

[0019] Figure label: 1. Central column; 11. Connecting step; 2. Inlet end seat; 3. Outlet end seat; 31. Connecting part; 4. Outlet; 5. Inlet; 6. Liquid equalization and distribution component; 7. Distribution channel; 8. Primary pre-filtration membrane; 81. Heparin-albumin complex layer; 82. Polyester filter screen; 9. Secondary targeting membrane; 91. Antibody modified plate; 92. Microcolumn; 93. Micropore; 10. Tertiary fine filtration membrane; 101. Hydrated molecular layer; 102. Fine filtration membrane. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0021] This invention addresses the issue of blood safety during intraoperative autologous blood transfusion in cancer patients, which is unsatisfactory with existing single-filtration technologies. Figure 1-4 As shown, the following technical solution is provided: a filtration device for clearing blood cancer cells using an antibody-modified filter membrane, comprising a device body, with an inlet 5 and an outlet 4 respectively provided at both ends of the device body. Inside the device body, from the inlet 5 towards the outlet 4, a primary pre-filtration membrane 8, a secondary targeting membrane 9, and a tertiary fine filtration membrane 10 are sequentially installed. A liquid equalization and diversion component 6 is provided between the primary pre-filtration membrane 8 and the outlet 4. The secondary targeting membrane 9 includes at least one antibody-modified plate 91, on which axially penetrating micropores 93 are evenly distributed. The inner wall of the micropores 93 is provided with… It is equipped with surface-covalently coupled EpCAM antibody, CK antibody and PD-L1 antibody. The first-stage pre-filtration membrane 8 can mechanically screen and intercept impurities >100μm in the blood (such as tissue debris and fibrin clots). The second-stage targeting membrane 9 adopts a microporous structure to prolong the contact time with cancer cells and improve the capture rate. The surface-covalently coupled EpCAM antibody can capture epithelial-derived CTCs, the CK antibody can recognize cytokeratin, and the PD-L1 antibody can cover cancer cells that highly express immune checkpoints, thus forming a multi-target capture network. The third-stage fine filtration membrane 10 can remove residual debris and achieve long-term anti-clogging.

[0022] Specifically, the technical solution in this embodiment mainly adapts the microporous structure of the secondary targeting membrane to the size of CTCs, while prolonging the blood retention time. Furthermore, the three antibodies EpCAM, CK, and PD-L1 form a full spectrum of CTCs with high expression of epithelial origin, cytokeratin, and immune checkpoints, which can capture CTCs of common tumors such as breast cancer, colorectal cancer, and lung cancer, with a single targeting membrane capture rate of ≥70%. At the same time, the liquid equalization and diversion component 6 avoids local blood accumulation, ensuring that the flow rate deviation on the filter membrane surface is ≤10%, preventing CTC escape or filter membrane damage caused by excessively high local flow rates.

[0023] The device comprises a central column 1, detachable inlet end seats 2 and outlet end seats 3 at both ends of the central column 1. The inlet port 5 is mounted on the inlet end seat 2, and the outlet port 4 is mounted on the outlet end seat 3. The device is compact, easy to assemble and disassemble, and facilitates the installation of the internal primary pre-filtration membrane 8, secondary targeted membrane 9, and tertiary fine filtration membrane 10. The central column 1 is made of medical-grade titanium alloy, the inlet and outlet end seats 2 and 3 are made of medical-grade polycarbonate, and the inlet and outlet ports 5 and 4 are made of silicone, compatible with standard medical Luer connectors. The inlet and outlet end seats 2 and 3 are threaded to the central column 1, allowing for manual assembly and disassembly without special tools, thus reducing filter replacement costs. The connection points between the inlet and outlet end seats 2 and the central column 1 are equipped with nitrile rubber O-rings, ensuring no leakage under 0.3 MPa pressure for 30 minutes.

[0024] In this embodiment, the primary pre-filtration membrane 8 includes a polyester filter 82 and a heparin-albumin complex layer 81 coated on the upper side of the polyester filter 82. It can inhibit platelet activation and initial coagulation. The rigid structure of the polyester filter can stably intercept impurities >100μm with an interception efficiency ≥99% and is resistant to blood erosion. In the heparin-albumin complex layer, heparin blocks coagulation cascade by inhibiting the activity of coagulation factor Xa, and albumin reduces platelet adsorption by occupying active sites on the filter membrane surface. It can work continuously for 2 hours at 37°C and a flow rate of 50mL / min. The polyester filter 82 can be made of food-grade PET material with a mesh size of 120 mesh (pore size 110μm) and a thickness of 150μm. The surface is plasma treated. The formulation of the heparin-albumin complex layer (81) can use a commonly used ratio, such as 0.5wt% heparin sodium, 2wt% human serum albumin, and 0.01MPBS as the solvent.

[0025] In this embodiment, the upper end of the liquid equalization and diversion component 6 is connected to the inlet 5, and the lower end is abutted against the primary pre-filtration membrane 8. The liquid equalization and diversion component 6 has obliquely arranged diversion channels 7 evenly distributed inside. The liquid equalization and diversion component 6 can guide blood cells to pass through evenly and reduce the risk of local blockage. The channel cross-section of the diversion channel 7 is circular, with low flow resistance. At a flow rate of 50 mL / min, it does not increase the blood delivery burden of the overall device. The liquid equalization and diversion component 6 is conical in shape, and the diversion channels are evenly distributed around the central axis. The channel inlet end and the inlet smoothly transition to avoid turbulence.

[0026] In this embodiment, at least two antibody-modified plates 91 are arranged axially. Adjacent antibody-modified plates 91 are close together and their micropores 93 are connected in a one-to-one correspondence, forming multiple capture paths and ensuring the capture rate. Specifically, the capture rate of two antibody-modified plates 91 connected in series is ≥90%, and the capture rate of three antibody-modified plates 91 connected in series is ≥98%. Furthermore, the alignment of the micropores 93 avoids turbulence caused by misalignment of blood channels. Figure 1As shown, the three antibody-modified plates are made of 91 medical-grade polyetheretherketone (PEEK), each with a diameter of 30mm and a thickness of 5mm, and three positioning pins on the edge.

[0027] In this embodiment, the surface covalently coupled EpCAM antibody, CK antibody, and PD-L1 antibody are arranged as micropillars 92 and arrayed on the inner wall of the micropores 93. The micropillars 92 can prolong the contact time with cancer cells and improve the capture rate. The micropillars 92 are spirally arranged along the inner wall of the micropores, which increases the antibody loading area on the inner wall of the micropores from 10 mm² / well to 30 mm² / well, and prolongs the contact time by 2 times. Specifically, stainless steel micropillars can be prepared on the inner wall of the micropores of the antibody modification plate 91 made of PEEK material using photolithography and electroforming processes, and arranged spirally.

[0028] In this embodiment, the three-stage fine filtration membrane 10 includes a fine filtration membrane 102 and a hydration molecular layer 101 coated on the surface of the fine filtration membrane 102. The hydration molecular layer 101 can reduce protein adsorption and cell adhesion, thereby reducing the clogging rate. Specifically, the fine filtration membrane 102 has a clearance rate of ≥99% for 5-50μm fragments, such as CTC lysis products and platelet aggregates, preventing microcirculatory embolism after reinfusion. The hydration molecular layer 101 can be made of polyethylene glycol to form a hydrophilic coating, further reducing protein adsorption and cell adhesion. After 8 hours of continuous operation, the membrane flux decrease rate is ≤10%. In this embodiment, the secondary targeting membrane 9 is disposed in the middle of the central column 1, the primary pre-filtration membrane 8 is installed between one end of the central column 1 and the inlet end seat 2, and the tertiary fine filtration membrane 10 is disposed between the other end of the central column 1 and the outlet end seat 3. The primary pre-filtration membrane 8 and the tertiary fine filtration membrane 10 are positioned by the connection relationship between the central column 1, the inlet end seat 2 and the outlet end seat 3, without the need for other connecting structures. The axial positioning of the filter membrane is achieved by the protrusion of the central column 1 and the connection part of the inlet end seat 2 and the outlet end seat 3, without the need for adhesives or clips.

[0029] In this embodiment, one end of the central column 1 is provided with a connecting step portion 11. The primary pre-filtration membrane 8 abuts axially against the connecting step portion 11. The liquid inlet seat 2 is threadedly connected to the outer side of the connecting step portion 11. The connecting step portion 11 can improve the connection strength between the central column 1 and the liquid inlet seat 2, and at the same time, the connecting step portion 11 can axially limit the primary pre-filtration membrane 8. One end of the liquid outlet seat 3 is provided with a connecting portion 31 that extends into the central column 1 for threaded connection. The tertiary fine filtration membrane 10 abuts axially against the connecting portion 31.

[0030] As shown in the device operation process in this embodiment: 1. Blood infusion: Intraoperative bleeding from the surgical field (such as pleural effusion in lung cancer surgery) enters the device's inlet through a negative pressure collection tube; 2. Equalization Pretreatment: Blood is evenly dispersed onto the surface of the primary pre-filtration membrane 8 through the 12 oblique channels of the equalization and diversion component 6, intercepting tissue fragments and fibrin clots >100μm; 3. Targeted CTC capture: Pretreated blood enters the central column 1 and flows sequentially through three tandemly connected antibody-modified plates 91. EpCAM antibody in microwell 93 captures epithelial-derived CTCs (such as breast cancer MCF-7), CK antibody recognizes cytokeratin-positive CTCs, and PD-L1 antibody captures CTCs with high expression of immune checkpoints (such as lung cancer A549). The three modified plates work together to achieve a CTC capture rate of ≥98%. 4. Fine filtration and anti-clogging: Blood flows through a three-stage fine filtration membrane to remove residual debris of 5-50μm, and the PEG hydration layer reduces protein adsorption and avoids clogging; 5. Blood reinfusion: The purified blood flows into the reinfusion tube through the outlet and is reinfused back into the patient's body through the autologous blood reinfusion pump to complete the autologous blood circulation.

[0031] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0032] Furthermore, in this invention, descriptions involving terms such as "primary," "secondary," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "primary" or "secondary" may explicitly or implicitly include at least one of that feature. In the description of this invention, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0033] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0034] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

Claims

1. A filtration device for removing blood cancer cells by combining antibody-modified filter membranes, characterized in that, The device includes a main body, with an inlet (5) and an outlet (4) at its two ends. Inside the main body, a primary pre-filtration membrane (8), a secondary targeting membrane (9), and a tertiary fine filtration membrane (10) are installed sequentially from the inlet (5) toward the outlet (4). A liquid equalization and diversion component (6) is provided between the primary pre-filtration membrane (8) and the outlet (4). The secondary targeting membrane (9) includes at least one antibody-modified plate (91). The antibody-modified plate (91) has axially penetrating micropores (93) evenly distributed on it. The inner sidewall of the micropores (93) is provided with surface covalently coupled EpCAM antibody, CK antibody, and PD-L1 antibody.

2. The filtration device for clearing blood cancer cells by binding antibody-modified filter membrane according to claim 1, characterized in that: The primary pre-filtration membrane (8) includes a polyester filter (82) and a heparin-albumin complex layer (81) coated on the upper side of the polyester filter (82).

3. The filtration device for clearing blood cancer cells by combining antibody-modified filter membranes according to claim 1, characterized in that: The upper end of the liquid equalization and diversion component (6) is connected to the liquid inlet (5), and the lower end is connected to the primary pre-filtration membrane (8). The liquid equalization and diversion component (6) has diversion channels (7) arranged obliquely inside.

4. The filtration device for clearing blood cancer cells by combining antibody-modified filter membranes according to claim 1, characterized in that: The antibody modification plates (91) are at least two arranged axially, with adjacent antibody modification plates (91) close together and the micropores (93) connected one-to-one.

5. The filtration device for clearing blood cancer cells by binding antibody-modified filter membrane according to claim 1 or 4, characterized in that: The surface covalently coupled EpCAM antibody, CK antibody and PD-L1 antibody are arranged in micropillars (92) and arrayed on the inner sidewall of the micropores (93).

6. The filtration device for clearing blood cancer cells by combining antibody-modified filter membranes according to claim 1, characterized in that: The three-stage fine filtration membrane (10) includes a fine filtration membrane (102) and a hydrated molecular layer (101) coated on the surface of the fine filtration membrane (102).

7. The filtration device for clearing blood cancer cells by combining antibody-modified filter membranes according to claim 1, characterized in that: The main body of the device includes a central column (1), a liquid inlet end seat (2) and a liquid outlet end seat (3) which are detachably disposed at both ends of the central column (1). The liquid inlet (5) is installed on the liquid inlet end seat (2) and the liquid outlet (4) is installed on the liquid outlet end seat (3).

8. The filtration device for clearing blood cancer cells by combining antibody-modified filter membranes according to claim 7, characterized in that: The secondary targeted membrane (9) is disposed in the middle of the central column (1), the primary pre-filtration membrane (8) is installed between one end of the central column (1) and the inlet end seat (2), and the tertiary fine filtration membrane (10) is disposed between the other end of the central column (1) and the outlet end seat (3).

9. The filtration device for clearing blood cancer cells by binding antibody-modified filter membrane according to claim 8, characterized in that: One end of the central column (1) is provided with a connecting step (11), the primary pre-filtration membrane (8) abuts against the connecting step (11) axially, and the liquid inlet seat (2) is threadedly connected to the outer side of the connecting step (11).

10. The filtration device for clearing blood cancer cells by combining antibody-modified filter membranes according to claim 8, characterized in that: One end of the liquid outlet seat (3) is provided with a connecting part (31) that extends into the central column (1) for threaded connection, and the three-stage fine filter membrane (10) abuts against the connecting part (31) axially.

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