A protein antigen combination for aortic dissection detection and its application

Abstract

The present invention belongs to the field of biological detection, and specifically relates to a protein antigen combination and application for aortic dissection detection. The specific technical scheme includes: the antigen composition includes a fragment of FBN2 protein and SPEG protein, the amino acid sequence of the fragment of FBN2 protein is shown in SEQ ID NO: 1, and the amino acid sequence of SPEG protein is shown in SEQ ID NO: 5. The present invention provides a protein antigen and a specific antigen combination, which can be used for the detection or diagnosis of aortic dissection by detecting the corresponding autoantibodies, and is particularly suitable for risk assessment and prediction before the onset of aortic dissection; and can be further prepared into related reagents or kits as needed.

Description

Technical Field

[0001] The invention belongs to the field of biological detection, and in particular relates to a protein antigen combination for aortic dissection detection and application thereof. Background Art

[0002] The aorta is composed of three layers: the intima, the media, and the adventitia. The intima is in direct contact with the blood in the blood vessels and is mainly composed of a layer of endothelial cells on the basement membrane. Aortic dissection is an emergency characterized by the separation of the wall membrane of the aorta, followed by the formation of a false lumen. On the one hand, the false lumen may compress the true aortic lumen, causing poor blood flow and even blocking the blood vessels; on the other hand, the blood in the false lumen is blocked and thrombus formation is easy; at the same time, aortic dissection is very likely to cause arterial rupture, which is life-threatening to the patient.

[0003] Aortic dissection is generally caused by a tear in the aortic intima. The high pressure in the aorta causes the blood in the artery to enter the media from the tear in the intima, causing the media to separate and expand along the long axis of the aorta, forming a state of separation between the true and false lumens of the aortic wall. In addition, about 13% of patients with aortic dissection do not have intimal tears, and the cause may be intramural hematoma (caused by bleeding in the media). Because there is no direct connection between the true lumen and the false lumen in aortic dissection caused by intramural hematoma, it is difficult to accurately diagnose through aortic angiography.

[0004] Aortic dissection develops rapidly and has a high early mortality rate. Many patients die before diagnosis, making it difficult to determine the overall incidence. Without treatment, aortic dissection is a fatal disease with an estimated mortality rate of 40% at the first onset. If not diagnosed and treated promptly, the mortality rate increases by 1% per hour within 48 hours of onset, and the annual mortality rate can reach more than 90%. Therefore, rapid and accurate diagnosis of aortic dissection has important clinical value.

[0005] At present, the diagnosis of aortic dissection mainly relies on clinical symptoms combined with imaging methods. According to the diagnosis and treatment guidelines for aortic dissection, sudden severe chest pain and / or back pain are the most typical manifestations of aortic dissection. The guidelines recommend that patients with acute chest pain be treated as suspected patients of aortic dissection and further laboratory tests and imaging examinations should be performed.

[0006] The imaging examinations for aortic dissection are mainly CT angiography (CTA) and magnetic resonance imaging (MRI). CTA is an interventional examination that requires the injection of iodine contrast agents, making it difficult to use in patients with iodine allergy, renal impairment, pregnancy, and hyperthyroidism. MRI scanning takes a long time, and patients with unstable circulation have low cooperation, and it is contraindicated for patients with life-support devices and metal objects in their bodies. Therefore, the application of imaging examinations is limited.

[0007] Aortic dissection can also be diagnosed by testing biomarkers in the blood. The guidelines recommend testing D-dimer as a biomarker. When D-dimer in the blood increases, especially when it increases rapidly in a short period of time, the possibility of aortic dissection increases, but it still needs to be differentiated from pulmonary embolism. D-dimer can be used as an exclusion indicator for the diagnosis of acute aortic dissection.

[0008] Autoantibodies are antibodies produced by an individual's immune system against an individual's own protein antigens. Under normal circumstances, the immune system produces antibodies in response to foreign proteins or substances in the body, but does not produce antibodies against the body's own cells and components. However, in certain special circumstances, especially pathological conditions, the immune system may also recognize one or more endogenous components of the body, leading to the production of autoantibodies.

[0009] Autoantibody testing has been widely used in clinical diagnosis, such as anti-thyroid autoantibody testing, antinuclear antibody testing, antiphospholipid antibody testing, etc. Disease-associated autoantibodies (AAB) are important biomarkers that can be used not only to diagnose specific diseases, but also to diagnose the early stages of diseases (single or rare symptoms) or diagnose diseases without typical clinical manifestations (atypical forms), and even to provide early warnings several years before the onset of the disease.

[0010] Currently, there is no specific biomarker for aortic dissection in clinical practice. Therefore, if a specific biomarker with accurate detection and high detection effect can be developed, it will have broad clinical application prospects. Summary of the invention

[0011] The purpose of the present invention is to provide a protein antigen combination and application for aortic dissection detection.

[0012] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an antigen, wherein the antigen is a fragment of FBN2 protein, and the amino acid sequence is shown in SEQ ID NO:1.

[0013] Correspondingly, the antigen combination comprising the antigen further comprises a SPEG protein, and the amino acid sequence of the SPEG protein is shown in SEQ ID NO:5.

[0014] Preferably, the antigen combination further comprises a fragment of SGCD protein, and the amino acid sequence of the fragment of SGCD protein is shown in SEQ ID NO:10.

[0015] Preferably, the antigen combination further comprises a fragment of SMTN protein, the amino acid sequence of the fragment of SMTN protein is shown in SEQ ID NO: 4; or; the antigen combination further comprises a fragment of COL3A1 protein, the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO: 8.

[0016] Preferably, the antigen combination further comprises a fragment of SMTN protein and a fragment of COL3A1 protein, the amino acid sequence of the fragment of SMTN protein is shown in SEQ ID NO:4, and the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO:8.

[0017] Preferably, the antigen combination further comprises a fragment of the MAT2A protein and a fragment of the CNN2 protein, the amino acid sequence of the MAT2A protein fragment is shown in SEQ ID NO: 3, and the amino acid sequence of the CNN2 protein fragment is shown in SEQ ID NO: 9.

[0018] Preferably, the antigen combination further comprises a fragment of COL3A1 protein, a fragment of MAT2A protein and a fragment of CNN2 protein, the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO: 8, the amino acid sequence of the fragment of MAT2A protein is shown in SEQ ID NO: 3, and the amino acid sequence of the fragment of CNN2 protein is shown in SEQ ID NO: 9;

[0019] or;

[0020] The antigen combination further comprises a fragment of EFEMP2 protein, a fragment of COL3A1 protein, a fragment of MAT2A protein and a fragment of CNN2 protein, wherein the amino acid sequence of the fragment of EFEMP2 protein is shown in SEQ ID NO: 7, the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO: 8, the amino acid sequence of the fragment of MAT2A protein is shown in SEQ ID NO: 3, and the amino acid sequence of the fragment of CNN2 protein is shown in SEQ ID NO: 9;

[0021] or;

[0022] The antigen combination also includes a fragment of FBN1 protein, a fragment of ACTA2 protein, a fragment of COL3A1 protein, a fragment of MAT2A protein and a fragment of CNN2 protein. The amino acid sequence of the fragment of FBN1 protein is shown in SEQ ID NO: 6, the amino acid sequence of the fragment of ACTA2 protein is shown in SEQ ID NO: 2, the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO: 8, the amino acid sequence of the fragment of MAT2A protein is shown in SEQ ID NO: 3, and the amino acid sequence of the fragment of CNN2 protein is shown in SEQ ID NO: 9.

[0023] Correspondingly, an antigen combination comprises a fragment of ACTA2 protein, a fragment of COL3A1 protein, a fragment of CNN2 protein, a fragment of SMTN protein and a fragment of ROBO4 protein; the amino acid sequence of the fragment of ACTA2 protein is shown in SEQ ID NO: 2, the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO: 8, the amino acid sequence of the fragment of CNN2 protein is shown in SEQ ID NO: 9, the amino acid sequence of the fragment of SMTN protein is shown in SEQ ID NO: 4, and the amino acid sequence of the fragment of ROBO4 protein is shown in SEQ ID NO: 11.

[0024] Correspondingly, an antigen, the antigen is SPEG protein, the amino acid sequence is shown in SEQ ID NO: 5; or; the antigen is a fragment of EFEMP2 protein, the amino acid sequence is shown in SEQ ID NO: 7.

[0025] Correspondingly, products for detecting / identifying aortic dissection, arterial tear, and arterial injury are prepared using the antigen and / or the antigen combination.

[0026] The present invention has the following beneficial effects:

[0027] The present invention provides specific protein markers related to aortic dissection, arterial tear, and arterial injury. By detecting the presence of autoantibodies corresponding to these protein markers in the human body, the risk of aortic dissection in the subject can be effectively assessed. The protein markers provided by the present invention, especially the protein marker composition, not only ensure the high specificity of the detection, but also greatly improve the sensitivity of the detection, which has extremely important practical significance in clinical application.

[0028] The biological samples used for detection can be serum, plasma, whole blood, saliva, oral mucosal swabs, urine, lymph, cerebrospinal fluid, etc. According to the specific situation, the biological samples can be pre-treated by extraction, dilution, enrichment, etc. The use method is diverse and simple and easy to operate.

[0029] The antigen or antigen combination provided by the present invention can also be used to prepare aortic dissection, arterial tear, arterial injury related autoantibody detection reagents or aortic dissection diagnostic reagents. It should be understood that the protein antigen combination can also be used to prepare an aortic dissection related autoantibody detection kit, and the kit can be prepared by referring to the method and reagents for aortic dissection related autoantibody detection using the protein antigen combination in the embodiments of the present invention, and can also be adjusted accordingly as needed.

[0030] In summary, the present invention provides a protein antigen and a specific antigen combination, which can be used for the detection or auxiliary diagnosis of aortic dissection, arterial tear, and arterial injury, and is also suitable for risk assessment and prediction of aortic dissection; and can be further prepared into related reagents or kits as needed. DETAILED DESCRIPTION

[0031] The present invention found that proteins FBN2, ACTA2, MAT2A, SMTN, SPEG, FBN1, EFEMP2, COL3A1, CNN2, SGCD and ROBO4 are closely related to the diagnosis of aortic dissection.

[0032] The present invention further found that the specific protein fragments or whole proteins of the above proteins have outstanding advantages in the diagnosis of aortic dissection. Specific protein fragments include: FBN2 (29-50), ACTA2 (30-120), MAT2A (238-290), SMTN (106-310), SPEG (1-113, whole protein), FBN1 (2235-2294), EFEMP2 (24-51), COL3A1 (90-152), CNN2 (148-309), SGCD (1-35), ROBO4 (451-733). Among them, the FBN2 protein fragment sequence is shown in SEQ ID NO: 1. The ACTA2 protein fragment sequence is shown in SEQ ID NO: 2. The MAT2A protein fragment sequence is shown in SEQ ID NO: 3. The SMTN protein fragment sequence is shown in SEQ ID NO: 4. The SPEG protein sequence is shown in SEQ ID NO: 5. The FBN1 protein fragment sequence is shown in SEQ ID NO: 6. The EFEMP2 protein fragment sequence is shown in SEQ ID NO: 7. The COL3A1 protein fragment sequence is shown in SEQ ID NO: 8. The CNN2 protein fragment sequence is shown in SEQ ID NO: 9. The SGCD protein fragment sequence is shown in SEQ ID NO: 10. The ROBO4 protein fragment sequence is shown in SEQ ID NO: 11.

[0033] Based on this new discovery, the present invention provides the use of the above protein in the preparation of products (such as kits) related to the detection and diagnosis of aortic dissection. The above proteins and protein fragments can be used alone or in combination to form a protein (fragment) composition for use.

[0034] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art. The data obtained are all average values ​​obtained after at least 3 repetitions, and all the data obtained in each repetition are valid data.

[0035] Example 1: Construction, expression, purification and performance demonstration of recombinant vector of protein antigen

[0036] 1. Construction and expression of antigen recombinant vectors Select the protein antigens listed in Table 1 and clone them by analyzing their sequence, structure, function and expression distribution.

[0037] Table 1 Correspondence table of protein antigen database ID

[0038]

[0039] Using human cDNA library (purchased from Invitrogen) or whole gene synthetic DNA as template, primers are designed respectively, and the gene of the protein is cloned into pET28 plasmid by molecular cloning methods such as PCR, enzyme digestion, and ligation. At the same time, HIS, c-myc and other tags are added to the N-terminus of the protein to form a fusion protein. The obtained recombinant expression vector is identified by DNA sequencing to confirm that it contains the correct protein gene. It should be noted that the added tag is only for the convenience of protein identification and extraction, and does not have a decisive effect on the function of the protein as an antigen. When used, no tag is added or other tags are added as needed.

[0040] The above recombinant plasmid containing the protein gene was transformed into E. coli BL21 (DE3) competent cells, and clones were picked and inoculated into LB medium and cultured in a shaking incubator at 37°C. When the bacterial density reached OD 600 When the pH value was about 0.8, the temperature was lowered to 16°C, and 0.1 mM isopropylthio-β-D-galactoside (IPTG) was added to each LB culture medium to induce expression overnight to obtain bacteria.

[0041] 2. Purification of antigens. Collect the induced expression bacteria by centrifugation and rinse twice with PBS. Resuspend and disperse the bacteria with lysis solution (add 5-10 mL lysis solution per gram of bacteria), put in an ice bath, and ultrasonically disrupt the bacteria (ultrasonic power 200W, disruption 5S, rest 5S). After disruption, centrifuge at 13000rpm, 10℃ for 20 minutes, take the supernatant, and purify it by two steps of Ni column affinity chromatography and molecular sieve chromatography. Use SDS-PAGE electrophoresis analysis to confirm the molecular weight and purity of the protein. After determining the concentration by Bradford method, store it at -80℃ for use. Obtain the purified protein to be tested and calculate the yield (the yield results are shown in Table 2).

[0042] 3. Performance of ELISA in detecting protein (fragment) antigens.

[0043] The solutions and reagents used in the test are as follows:

[0044] The coating buffer is PBS buffer, pH = 7.4. The preparation method is as follows: accurately weigh 3.58g Na2HPO4·12H2O, 0.23g KH2PO4·2H2O, 0.2g KCl, 8.0g NaCl, dissolve them in water, and add water to make up to 1L.

[0045] Blocking solution / sample diluent / antibody diluent: Dissolve 10g BSA (bovine serum albumin) in coating buffer and add water to make up to 1L.

[0046] Washing solution: Prepare and use immediately. Add 0.05% Tween20 (V / V) to the coating buffer before use, pH=7.4.

[0047] TMB colorimetric reagent was purchased from KPL Company.

[0048] Stop solution: 1M hydrochloric acid.

[0049] (1) Solid-phase coating of the test protein. Dilute the purified test antigen obtained in step 2 to 5 μg / mL with coating buffer, add 50 μL to each well of a 96-well plate, and coat overnight at 4°C. The next day, pour out the solution, spin dry, and wash three times with washing solution, 200 μL per well each time. Then add 200 μL of blocking solution to each well, incubate at room temperature for 1 hour, pour out the blocking solution, spin dry, and wash three times with washing solution, 200 μL per well each time, and spin dry again; obtain the solid-phase coated antigen in the 96-well plate.

[0050] (2) Add the sample to be tested. Dilute the human serum to be tested 100 times with the sample diluent, add it to the 96-well plate containing the protein to be tested, and add 50 μL of the diluted sample to each well. Then place the 96-well plate on a microplate shaker and incubate at room temperature for 1 hour; spin dry, wash three times with washing solution, 200 μL per well each time, and spin dry again.

[0051] (3) Add enzyme-labeled secondary antibody. Dilute 1.0 mg / mL horseradish peroxidase-labeled recombinant goat anti-human immunoglobulin G antibody (purchased from Jackson ImmunoResearch Inc.) 20,000 times with antibody diluent and add 50 μL to each well of the 96-well plate treated in step 3. Then place the 96-well plate on a microplate shaker and incubate at room temperature for 0.5 h. Shake the plate dry and wash three times with washing solution, 200 μL per well each time, and shake dry again.

[0052] (4) Color development and optical density reading. After the treatment in step (3), add 50 μL of TMB colorimetric reagent to each well of the 96-well plate, shake for 15 seconds, react in the dark at room temperature for 15 minutes, and then add 50 μL of stop solution; then use an ELISA reader to read the absorbance value at a wavelength of 450 nm to obtain the detection signal (S) of each sample to be tested.

[0053] (5) Sensitivity and specificity analysis. 48 positive samples (sera from patients diagnosed with aortic dissection) and 46 negative samples (sera from healthy subjects) were taken respectively, and the detection signal (S) of each sample was measured according to the above method (absorption value at a wavelength of 450 nm). It should be noted that the detection in the present invention is to detect autoantibodies corresponding to antigens or antigen combinations, which will not be repeated in the following text. Taking the negative samples as negative reference samples, the mean value (M) and standard deviation (SD) of the detection signals (S) of all negative reference samples are calculated, and M+2SD is taken as the Cut Off value. Samples with a detection signal (S) ≥ Cut Off value (S ≥ M+2SD) are defined as positive; samples with a detection signal (S) < Cut Off value (S < M+2SD) are defined as negative.

[0054] Specificity and sensitivity were calculated based on the positive and negative results of the samples. Among them, specificity refers to the proportion of samples from healthy subjects that were correctly judged as negative, that is, the number of samples correctly judged as negative in negative samples divided by the total number of negative samples. Sensitivity refers to the proportion of samples from patients with aortic dissection that were correctly judged as positive, that is, the number of samples judged as positive in positive samples divided by the total number of positive samples. The sensitivity and specificity of each tested antigen when the sample was tested separately were calculated. The results are shown in Table 2. Among them, the whole protein of FBN2, FBN1, COL3A1 and ROBO4 proteins was not obtained.

[0055] Table 2 Sensitivity and specificity of each protein antigen

[0056]

[0057] Example 2: Selection of protein fragments and performance display

[0058] Referring to the method of Example 1, the sequence, structure, function and expression distribution of the proteins in Table 1 were analyzed, and different fragments were selected for cloning, wherein protein SPEG did not clone fragments, and the whole protein was used. The specific selected protein fragments are shown in Table 3.

[0059] Table 3 Cloning sequence correspondence of protein antigen fragments

[0060]

[0061] The yield of each fragment was calculated by referring to the method of Example 1. The same samples as those of Example 1 were used to detect and calculate the sensitivity and specificity of each antigen in Table 3 when the sample was tested alone. The results are shown in Table 4.

[0062] Table 4 Sensitivity and specificity of each antigen

[0063]

[0064] According to the results in Table 4, one optimal fragment was selected from each protein antigen, and the results are shown in Table 5. The preferred protein antigen fragment not only has good specificity and sensitivity, but also has a high yield, which is conducive to subsequent amplification and production.

[0065] Table 5 Preferred antigen fragment sensitivity and specificity display table

[0066]

[0067] Example 3: Demonstration of detection effect of antigen combination

[0068] Different antigen fragments were selected from Table 5 of Example 2 to form different antigen combinations, and the antigen combinations are shown in Table 6. It should be noted that the inventors did not only conduct the combination test in Table 6; the inventors obtained the antigen combinations shown in Table 6 after a large number of preliminary experiments, and due to space limitations, only some combinations with better effects were selected.

[0069] Table 6 Comparison table of antigen combinations

[0070]

[0071] 2. Take 48 positive samples (aortic dissection patients) and 46 negative samples (healthy subjects), refer to the detection method of Example 1, and use the antigen combinations in Table 6 to perform sensitivity and specificity tests on the above samples.

[0072] In the antigen combination, the definition method of the positive and negative of a single antigen is referred to Example 1. The overall sensitivity and specificity of the antigen combination are defined as follows:

[0073] For an antigen combination, when a test signal obtained by using any one of the antigens in the combination for a serum sample is a positive test signal, the serum sample is a positive sample; otherwise, the serum sample is a negative sample.

[0074] Based on the above positive and negative definition methods, the test obtains positive and negative results for an antigen combination test, and then calculates the sensitivity of the antigen combination in the patient sample.

[0075] Among them, sensitivity refers to the proportion of samples from patients with aortic dissection that are correctly judged as positive, that is, the number of samples judged as positive in all samples from patients with aortic dissection divided by the total number of samples from all patients with aortic dissection; specificity refers to the proportion of samples from healthy subjects that are correctly judged as negative, that is, the number of samples from healthy subjects judged as negative in healthy subject samples divided by the total number of healthy subject samples.

[0076] The sensitivity and specificity results obtained for each group of antigen combination tests are shown in Table 7.

[0077] Table 7 Comparison of sensitivity and specificity test results of each group of antigen combinations

[0078]

[0079] In later applications, one or more of the ideal candidate antigens provided by the present invention can be selected as needed to prepare a diagnostic kit.

[0080] The embodiments described above are only descriptions of the preferred modes of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations, modifications, and substitutions made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. An antigen polypeptide for detecting / identifying aortic dissection, arterial tear, or arterial injury, characterized in that: The antigen polypeptide is a fragment of FBN2 protein, and the amino acid sequence is shown in SEQ ID NO:

1.

2. An antigen polypeptide combination, characterized in that: The method comprises the antigen polypeptide according to claim 1, and further comprises a SPEG protein, wherein the amino acid sequence of the SPEG protein is shown in SEQ ID NO:

5.

3. The antigen polypeptide combination according to claim 2, characterized in that: The antigen polypeptide combination also includes a fragment of SGCD protein, and the amino acid sequence of the fragment of SGCD protein is shown in SEQ ID NO:

10.

4. The antigen polypeptide combination according to claim 3, characterized in that: The antigen polypeptide combination further includes a fragment of SMTN protein, the amino acid sequence of which is shown in SEQ ID NO: 4; or; the antigen polypeptide combination further includes a fragment of COL3A1 protein, the amino acid sequence of which is shown in SEQ ID NO:

8.

5. The antigen polypeptide combination according to claim 3, characterized in that: The antigen polypeptide combination also includes a fragment of SMTN protein and a fragment of COL3A1 protein. The amino acid sequence of the fragment of SMTN protein is shown in SEQ ID NO:4, and the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO:

8.

6. The antigen polypeptide combination according to claim 5, characterized in that: The antigen polypeptide combination also includes a fragment of MAT2A protein and a fragment of CNN2 protein. The amino acid sequence of the fragment of MAT2A protein is shown in SEQ ID NO:3, and the amino acid sequence of the fragment of CNN2 protein is shown in SEQ ID NO:

9.

7. The antigen polypeptide combination according to claim 2, characterized in that: The antigen polypeptide combination further comprises a fragment of COL3A1 protein, a fragment of MAT2A protein and a fragment of CNN2 protein, wherein the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO: 8, the amino acid sequence of the fragment of MAT2A protein is shown in SEQ ID NO: 3, and the amino acid sequence of the fragment of CNN2 protein is shown in SEQ ID NO: 9; or; The antigen polypeptide combination further comprises a fragment of EFEMP2 protein, a fragment of COL3A1 protein, a fragment of MAT2A protein and a fragment of CNN2 protein, wherein the amino acid sequence of the fragment of EFEMP2 protein is shown in SEQ ID NO: 7, the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO: 8, the amino acid sequence of the fragment of MAT2A protein is shown in SEQ ID NO: 3, and the amino acid sequence of the fragment of CNN2 protein is shown in SEQ ID NO: 9; or; The antigen polypeptide combination also includes a fragment of FBN1 protein, a fragment of ACTA2 protein, a fragment of COL3A1 protein, a fragment of MAT2A protein and a fragment of CNN2 protein. The amino acid sequence of the fragment of FBN1 protein is shown in SEQ ID NO: 6, the amino acid sequence of the fragment of ACTA2 protein is shown in SEQ ID NO: 2, the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO: 8, the amino acid sequence of the fragment of MAT2A protein is shown in SEQ ID NO: 3, and the amino acid sequence of the fragment of CNN2 protein is shown in SEQ ID NO:

9.

8. An antigen polypeptide combination, characterized in that: The antigen polypeptide combination includes a fragment of ACTA2 protein, a fragment of COL3A1 protein, a fragment of CNN2 protein, a fragment of SMTN protein and a fragment of ROBO4 protein; the amino acid sequence of the fragment of ACTA2 protein is shown in SEQ ID NO: 2, the amino acid sequence of the fragment of COL3A1 protein is shown in SEQ ID NO: 8, the amino acid sequence of the fragment of CNN2 protein is shown in SEQ ID NO: 9, the amino acid sequence of the fragment of SMTN protein is shown in SEQ ID NO: 4, and the amino acid sequence of the fragment of ROBO4 protein is shown in SEQ ID NO:

11.

9. An antigen polypeptide for detecting / identifying aortic dissection, arterial tear, or arterial injury, characterized in that: The antigen polypeptide is a fragment of EFEMP2 protein, and the amino acid sequence is shown in SEQ ID NO:

7.

10. A reagent or kit for detecting / identifying aortic dissection, arterial tear, or arterial injury prepared using the antigen polypeptide according to claim 1 or 9 or the antigen polypeptide combination according to any one of claims 2 to 8.

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