阅读说明：本技术 一种从母体中在体原位捕获胎儿真核红细胞的装置及其应用 (Device for in-vivo capturing fetal eukaryotic red blood cells from maternal body and application thereof ) 是由 张弢 *** 宋婉云 杨贵和 于 2019-11-29 设计创作，主要内容包括：本发明公开了一种原位捕获胎儿有核红细胞的装置及其应用,所述装置包括推拉装置、空筒容器、穿刺头和聚合物导丝,所述空筒容器两端开口,一端连接穿刺头,另一端放置推拉装置,推拉装置与空筒容器的内壁密封接触,并且能够沿空筒容器的内壁滑动,所述聚合物导丝穿过穿刺头内部,并且连接推拉装置的底部。采用本发明装置,可以实现与母体外周血作较短时间的接触,就能捕获数量稀少的胎儿有核红细胞,并且可以在体、原位捕获胎儿有核红细胞捕,避免了大量抽取母体外周血,并使用离心等低效率方法进行富集、分离胎儿有核红细胞因而耗时长、花费高等问题,方法成本低,耗时短,捕获效率高。(The invention discloses a device for capturing fetal nucleated red blood cells in situ and application thereof. The device can realize the contact with maternal peripheral blood for a short time, can capture a small amount of fetal nucleated red blood cells, can capture the fetal nucleated red blood cells in vivo and in situ, avoids the problems of long time consumption, high cost and the like caused by the adoption of low-efficiency methods such as centrifugation and the like for enrichment and separation of the fetal nucleated red blood cells, and has low cost, short time consumption and high capture efficiency.)

1. The device for capturing the fetal nucleated red blood cells in situ is characterized by comprising a push-pull device (1), an empty tube container (2), a puncture head (3) and a polymer guide wire (4), wherein the two ends of the empty tube container (2) are open, one end of the empty tube container is connected with the puncture head (3), the other end of the empty tube container is used for placing the push-pull device (1), the push-pull device (1) is in sealing contact with the inner wall of the empty tube container (2) and can slide along the inner wall of the empty tube container (3), and the polymer guide wire (4) penetrates through the interior of the puncture head (3) and is connected with the bottom of the push-pull device (1).

2. A device for in situ capture of foetal nucleated red blood cell according to claim 1, wherein the push-pull device (1) comprises a push-pull rod (1-1) and a piston (1-2) connected together, the piston (1-2) being in sealing contact with the inner wall of the empty cartridge container (2); the puncture head (3) is detachable.

3. A device for capturing nucleated red blood cells of a fetus according to claim 1, wherein said polymeric guide wire (4) is made of a high molecular material and has a carboxyl group attached to its surface.

4. A device for in situ capture of fetal nucleated red blood cells according to claim 3, wherein said polymeric material is selected from natural polymeric materials selected from cellulose or proteins, preferably cellulose; the synthetic polymer material is selected from polyamide, polyester, polyurethane, polyacrylate or polyether amide, and is further selected from polyamide 6, polyamide 66, polyamide 610, polyamide 1010, polyamide 1212, polyethylene glycol terephthalate, polybutylene terephthalate, polylactic acid, lactic acid-glycolic acid copolyester, polycaprolactone, polyether polyurethane, polyester polyurethane, polyacrylate fibers obtained by copolymerizing methyl methacrylate and other acrylate monomers, or various polyether-polyamide copolymers, preferably polyamide 6, polyamide 66, polyamide 610, polyamide 1010 or polyethylene glycol terephthalate.

5. A device for in situ capture of fetal nucleated red blood cells according to claim 1, wherein said polymeric guidewire (4) is a polymeric guidewire with surface attached carboxybetaine methacrylate (CBMA) oligomer.

6. A device for in situ capture of foetal nucleated red blood cells according to claim 1, wherein the movable distance of the push-pull device (1) is 1-20cm, the empty cartridge container (2) has a capacity not exceeding 2mL, the inner diameter of the piercing head (3) is not less than 0.3mm, the polymeric guide wire (4) has a diameter of 0.1-0.3mm, a length of 1-20 cm.

7. A method for capturing foetal nucleated red blood cells in situ using the device according to any one of claims 1 to 6, comprising the steps of:

1) sucking a solution containing fetal nucleated red blood cell antibodies into an empty cylinder container (2) through a push-pull device (1), connecting the antibodies to a polymer guide wire (4), and then discharging the solution;

2) the normal saline is sucked into the empty cylinder container (2) through the push-pull device (1), the polymer guide wire (4) is soaked in the normal saline, then the puncture head (3) is inserted into a subcutaneous blood vessel, the normal saline is discharged through the push-pull device (1), the polymer guide wire (4) is exposed in the blood, and after the polymer guide wire is fully contacted with the blood, the device is pulled out;

3) and (3) taking down the polymer guide wire (4) which is fully contacted with blood, and eluting to obtain the blood-purifying agent.

8. A method of capturing fetal nucleated red blood cells in situ according to claim 7, wherein said fetal nucleated red blood cell antibodies include but are not limited to CD34, CD71 or Hoechst33258, the preferred antibody is CD 71.

9. A method for in situ capture of foetal nucleated red blood cells according to claim 7, wherein the method of attaching the antibody to the polymeric guidewire (4) is by carbodiimide/N-hydroxysuccinimide coupling reaction (EDC/NHS).

10. A method of capturing fetal nucleated red blood cells in situ according to claim 7, wherein said contacting with blood is sufficient for a period of time of 1-60 minutes, preferably 10-30 minutes.

Technical Field

The invention relates to a device for capturing fetal eukaryotic red blood cells from a mother body in situ in vivo and application thereof, belonging to the technical field of medical instruments for capturing fetal nucleated red blood cells.

Background

Cells with the quantity lower than 100 per milliliter of blood are called rare cells, and a plurality of types of rare cells have important research values, wherein Circulating Tumor Cells (CTCs) and fetal Nucleated Red Blood Cells (NRBCs) have wide prospects in clinical diagnosis and treatment and are widely researched. The fetal nucleated red blood cells contain complete genetic information of the fetus, are convenient for genetic and molecular biological analysis, and are richer in maternal peripheral blood in the early pregnancy than other fetal cells. Therefore, NRBCs have important research significance in the field of prenatal diagnosis of fetuses, and whether the fetuses have congenital malformation or genetic diseases, such as Down syndrome, gene copy number variation and the like, can be diagnosed by detecting NRBCs genes.

Currently, in order to separate and enrich NRBCs, a widely used method is to separate blood from a human body, and to separate NRBCs based on a physical method or an immunoaffinity method by utilizing the difference in size, density, deformability, and cell surface expression of specific antigens, etc., between the NRBCs and normal blood cells. Such as Nagy et al (naggy G R, BAN Z, SIPOS F, et al, isolation of epsilon-halo-chain positive magnetic cells with micro-manipulation for preliminary diagnosis [ J ] preliminary diagnosis,2005,25(5): 398: -402), using the blood after double density gradient centrifugation to mix with immunomagnetic beads, using the specific binding of antigen-antibody, and further using magnetic field to achieve the in vitro capture of fetal nucleated red blood cell NRBCs. The patent document with the Chinese patent application publication number of CN108795685A discloses a method for capturing and releasing fetal nucleated red blood cells by utilizing a microfluidic chip, the patent utilizes the microfluidic chip containing a micro-channel and a specific target substance to realize the specific capture of the fetal nucleated red blood cells, and further utilizes optical cutting to cut off a connecting arm connected with the target cells to realize the release of the target cells; the patent document with the publication number of CN108535228A of Chinese invention patent application utilizes the difference of fetal nucleated erythrocyte volume and surface antigen, combines the micro-fluidic technology and the immunoaffinity effect through a microarray structure chip with specific geometric arrangement, and realizes the capture and enrichment of fetal cells with different sizes; the patent document with the Chinese patent application publication number of CN105063181A discloses a method for enriching NRBCs by a density gradient centrifugation method, adding the NRBCs on a substrate chip modified with antibodies for standing and capturing, and then identifying a fetus Y chromosome by a FISH probe to separate fetus nucleated red blood cells from the peripheral circulating blood of a pregnant woman for noninvasive prenatal diagnosis; the patent document with the Chinese patent application publication number of CN105420086A discloses a single cell positioning microporous membrane, application and a single cell automatic acquisition device, wherein the device disperses single cells in a positioning microporous filter membrane, and opens the corresponding filter membrane after automatic identification by a fluorescence microscope so that the cells fall into a collection hole to achieve the purpose of separation; the Chinese patent application publication No. CN101310025A discloses a system and method for enriching analytes, which increases the concentration of target cells by 10000 times by forming a microarray enrichment analysis system instrument; chinese patent application publication nos. CN102884170A and CN107604039A disclose a micro-fluidic sorter for detecting and separating cells, which realizes the separation of NRBCs from other cells by the difference in cell deformability in a linear or spiral narrow flow channel in the micro-fluidic sorter; the patent document with the Chinese patent application publication number of CN108546676A discloses a method for separating and enriching rare cells in peripheral blood by a tunnel magnetic field technology, wherein magnetic beads and target cell cells are connected in cell incubation through antibody-antigen interaction, and then the enrichment and separation are realized by flowing through a tunnel magnetic field; the patent document with the Chinese patent application publication number of CN106119189A discloses a separation and purification method of fetal nucleated red blood cells and a kit for separating and enriching NRBCs by centrifugation and magnetic beads marked by antibodies; the Chinese patent application publication No. CN103797368A discloses a method for detecting fetal nucleated red blood cells, which comprises forming a compound by a CD147 antibody and a blood sample containing NRBCs, and screening and detecting under a microscope after density gradient centrifugation and enrichment; the patent document with Chinese patent application publication number CN103103161A discloses a separation and purification method of fetal nucleated red blood cells and a Down syndrome screening kit, wherein magnetic beads marked by CD54 antibodies are combined with NRBCs and then separated by a magnetic separator; the patent document with the Chinese patent application publication number of CN107312748A discloses a method for sorting fetal nucleated red blood cells, wherein nano-microspheres are connected to NRBCs through antibody-antigen action so as to enlarge the density difference with other cells, and then are enriched by centrifugal separation; the patent document with Chinese patent application publication No. CN105043831A discloses a nano material for capturing nucleated red blood cells, wherein CD147 antibody is connected to a base film formed by spreading nanoparticles on a glass substrate through streptavidin, and the base film is contacted with NRBCs enriched by a gradient centrifugation method and identified by an immunofluorescence staining method; the patent document with the Chinese patent application publication number of CN104977284A discloses a method for capturing and identifying fetal nucleated red blood cells, which comprises the steps of firstly preparing a nano basement membrane for modifying an antibody and connecting biotin, enriching NRBCs by a gradient centrifugation method and then contacting the basement membrane, and identifying by a double-positive immunofluorescence staining method; chinese patent application publication No. CN108220453A discloses a noninvasive prenatal paternity test method and a kit thereof, wherein optimized technologies such as density gradient centrifugation, immunomagnetic bead negative selection, immunofluorescence, laser microdissection, single cell amplification and the like are combined together to form a system identification method, fetal nucleated red blood cells in the peripheral blood of a pregnant woman are successfully separated, and the fetal nucleated red blood cells are successfully applied to paternity test; the Chinese patent application publication No. CN107312706A discloses a biological reaction carrier for biological sample extraction, wherein carboxyl/amino is modified on the inner wall of a reaction cavity (sphere, hemisphere, groove, micro-channel, capillary), and then an antibody is connected to contact with a cell suspension to realize the extraction of NRBCs; the patent document with the Chinese patent application publication number of CN106488981A discloses a preparation method of fetal Nucleated Red Blood Cells (NRBCS) for diagnostic test, which comprises the steps of firstly obtaining cell fractions containing NRBCs by density gradient centrifugation and enrichment, further carrying out flow cytometry sorting or sorting by micromanipulation after carrying out fluorescence labeling after magnetic activated cell sorting; the patent document with the Chinese patent application publication number of CN103602632A discloses a technical scheme for separating fetal nucleated red blood cells from peripheral blood of a pregnant woman by a centrifugal separation method; the patent document with the Chinese invention patent application publication number of CN104662424A discloses a method for selectively capturing and releasing circulating cells through stimulation on a nano-structure device, wherein a nanowire array is constructed on a substrate, one end of a nanowire is fixed, the other end of the nanowire is connected with an antibody, a temperature-sensitive response material layer is arranged between the antibody and the nanowire, the temperature-sensitive response material layer has a compact structure at a first temperature to capture cells, and the temperature-sensitive response material layer is unfolded to release the captured cells at a second temperature; the patent document with the publication number of CN108753573A in the Chinese invention patent application discloses a method for capturing and identifying fetal nucleated red blood cells in a microfluidic chip, which enables nanoparticles to flow through the microfluidic chip so as to form a coating on the inner wall, modify streptavidin, and graft a biologically modified antibody for NRBCs sorting.

At present, most methods for separating and enriching NRBCs are in vitro capture, more peripheral blood needs to be extracted, in-situ capture in vivo is difficult to realize, the sample volume is small, and the blood volume effectively contacting the periphery of a parent body is small; furthermore, because NRBCs are present in less amounts in maternal peripheral blood (less than 100 per ml), the in vitro capture uncertainty is higher than that of in vivo in situ capture; furthermore, in vitro capture needs to be performed in a specific experimental site, and the captured cells are difficult to store or transport without damage, which is not favorable for downstream gene detection and analysis.

Disclosure of Invention

The purpose of the invention is as follows: the invention mainly aims to provide a device for capturing fetal eukaryotic red blood cells from a maternal body in situ in vivo and application thereof.

The technical scheme is as follows: in order to achieve the purpose, the invention adopts the following technical scheme:

the device comprises a push-pull device, an empty cylinder container, a puncture head and a polymer guide wire, wherein the two ends of the empty cylinder container are open, one end of the empty cylinder container is connected with the puncture head, the push-pull device is placed at the other end of the empty cylinder container, the push-pull device is in sealing contact with the inner wall of the empty cylinder container and can slide along the inner wall of the empty cylinder container, and the polymer guide wire penetrates through the interior of the puncture head and is connected with the bottom of the push-pull device.

Preferably, the push-pull device comprises a push-pull rod and a piston which are connected together, and the piston is in sealing contact with the inner wall of the empty cylinder container. The puncture head can be detached.

The push-pull device can also be designed in an integrated way, the hollow cylinder container can be in a cylindrical shape or a square cylinder shape, and the opening sizes of the two ends of the hollow cylinder container can be the same or different. The puncture head can be detached or can be integrally designed with the empty cartridge container.

Preferably, the polymer guide wire is made of a high molecular material, and a carboxyl group is connected to the surface of the polymer guide wire.

The high polymer material is selected from natural high polymer materials or artificially synthesized high polymer materials, and the natural high polymer materials are selected from cellulose or protein, preferably cellulose; the synthetic polymer material is selected from polyamide, polyester, polyurethane, polyacrylate or polyether amide, and is further selected from polyamide 6, polyamide 66, polyamide 610, polyamide 1010, polyamide 1212, polyethylene glycol terephthalate, polybutylene terephthalate, polylactic acid, lactic acid-glycolic acid copolyester, polycaprolactone, polyether polyurethane, polyester polyurethane, polyacrylate fibers obtained by copolymerizing methyl methacrylate and other acrylate monomers, or various polyether-polyamide copolymers, preferably polyamide 6, polyamide 66, polyamide 610, polyamide 1010 or polyethylene glycol terephthalate.

The polymer guide wire surface is connected with carboxyl groups by adopting a chemical grafting method, a surface coating method and the like, and preferably adopting a chemical grafting method. The carboxyl group is a carboxyl group with zwitterionic property, namely, the carboxyl group is connected to form an anionic group, and simultaneously, a quaternary ammonium group with cationic property is also connected to the same chemical structure, and the monomer for grafting also has an acrylate or methacrylate structure. A further preferred chemical structure is a carboxybetaine (meth) acrylate structure having the general formula wherein the preferred structure is R ═ CH₃Carboxybetaine methacrylate (CBMA) of 1, n, and 1.

R＝H,CH₃,n＝1,2,3,...,m＝1,2,3,...

Namely, the polymer guide wire is a high molecular material guide wire with the surface connected with Carboxyl Betaine Methacrylate (CBMA) oligomer.

Preferably, the push-pull device has a movable distance of 1-20cm, the empty cartridge container has a capacity of not more than 2mL, the puncture tip inner diameter is not less than 0.3mm, and the polymer guide wire has a diameter of 0.1-0.3mm and a length of 1-20 cm.

The method for capturing the fetal nucleated red blood cells in situ by using the device comprises the following steps:

1) sucking the solution containing the fetal nucleated red blood cell antibody into an empty cylinder container through a push-pull device, connecting the antibody to a polymer guide wire, and then discharging the solution;

2) the normal saline is sucked into the empty cylinder container through the push-pull device, so that the polymer guide wire is soaked in the normal saline, then the puncture head is inserted into a subcutaneous blood vessel, the normal saline is discharged through the push-pull device, so that the polymer guide wire is exposed in the blood, and the device is pulled out after the polymer guide wire is fully contacted with the blood;

3) and (4) taking down the polymer guide wire which is fully contacted with blood, and eluting to obtain the polymer guide wire.

The fetal nucleated red blood cell antibody includes but is not limited to CD34, CD71 or Hoechst33258, and the preferred antibody is CD 71. The antibody is linked before capturing the cells, without prior linking, thereby avoiding antibody failure during storage.

Preferably, the method of attaching the antibody to the polymeric guidewire (4) uses a carbodiimide/N-hydroxysuccinimide coupling reaction (EDC/NHS) attachment.

Preferably, the blood is contacted sufficiently for a period of time of 1 to 60 minutes, preferably 10 to 30 minutes.

The principle of the method available for elution in step 3) is a well-known method in cell biology, and the fetal nucleated red blood cells obtained by elution can be further used for genetic analysis and detection, so that all genetic information of a fetus can be obtained.

The principle of capturing fetal nucleated red blood cells using the device is as follows:

the polymer guide wire penetrates through the puncture head and is tightly connected with the push-pull device, and the guide wire can move back and forth through the movement of the push-pull device. When the push-pull device is arranged at the end closest to the puncture head, a part of the guide wire is exposed outside the device, and when the push-pull device is arranged at the end farthest from the puncture head, the guide wire is completely retracted in the device. When the guide wire is connected with the device, a complete device for capturing the fetal nucleated red blood cells from the mother in situ is obtained.

The device disclosed by the invention is ingenious in design, wherein the polymer guide wire is soft in property, can float along with blood flow in a blood vessel in vivo and cannot be adhered to the blood vessel wall, so that the polymer guide wire is contacted with more blood, and the specific capture of rare nucleated red blood cells is realized. In addition, the device of the invention can simply and easily connect the antibody, can realize the antibody connection by alternately sucking a plurality of solutions before puncturing, and realizes the connection of the instrument and the antibody (medicine) on site by simple operation. Therefore, the antibody which can be connected with the instrument and can be kept active only under special conditions (low temperature and short time) can be avoided during the manufacture of the instrument, and the inactivation of the antibody during later storage and transportation and use can be avoided.

The technical effects are as follows: compared with the prior art, the device can realize the short-time contact with maternal peripheral blood, capture the fetal nucleated red blood cells with rare quantity, be used for further genetic analysis and detection and the like, and obtain the genetic information of the fetus, thereby providing a basis for screening early genetic diseases. In addition, the device provided by the invention can capture the fetal nucleated red blood cells in vivo and in situ, avoids the problems of long time consumption, high cost and the like caused by extracting a large amount of maternal peripheral blood and using low-efficiency methods such as centrifugation to enrich and separate the fetal nucleated red blood cells, and has low cost, short time consumption and high capture efficiency.

Drawings

FIG. 1: the invention discloses a schematic overall structure diagram of a device for capturing fetal nucleated red blood cells in situ.

FIG. 2: embodiment 2 of the present invention is an overall structure schematic diagram of a device for capturing fetal nucleated red blood cells in situ, wherein: a is the state that the functionalized guide wire is protected in the device, B is the intermediate state of a part of the guide wire pushing device, and C is the state that the guide wire pushing device is exposed to the external environment.

FIG. 3: the invention discloses a fluorescent photograph of nucleated red blood cells captured from isolated pregnant woman blood by using a fetal nucleated red blood cell capturing device, wherein: ABC is the result of three different experiments.

FIG. 4: the invention relates to a fluorescence-labeled in situ hybridization (FISH) detection result diagram of fetal nucleated red blood cells captured by the fetal nucleated red blood cell capturing device.

Detailed Description

The present invention will be further described with reference to the following examples.