200 results about "Indirect elisa" patented technology

The invention discloses an indirect ELISA kit for distinguishing porcine actinobacillus pleuropneumoniae wild virus infection and vaccine immunity and application, and belongs to the technical field of biology. According to the indirect ELISA kit, screened ApxIVA truncated protein serves as a coating antigen, the amino acid sequence of the ApxIVA truncated protein is shown in SEQ ID NO.3, the ApxIVA truncated protein can be subjected to soluble expression in escherichia coli, only one His tag and one S tag are carried, and the structure and the function of the ApxIVA truncated protein are close to those of natural ApxIVA. The pxIVA truncated protein is used as an antigen, an indirect ELISA method and kit for distinguishing APP wild strain infection and gene deletion vaccine immunity are established, the kit has the advantages of high specificity, low background value, low cost and short detection time, and the kit has the advantages of improving animal husbandry APP diagnosis accuracy and improving animal husbandry APP diagnosis accuracy. And the method has important significance in the aspects of optimizing prevention and control measures and guaranteeing animal health and production benefits.

The invention discloses a pseudorabies virus variant gD protein as well as a preparation method and application thereof. The amino acid sequence of the pseudorabies virus variant gD protein is shown as a sequence 1 in a sequence table, and the nucleotide sequence of the pseudorabies virus variant gD protein is shown as a sequence 2 in the sequence table. The pseudorabies virus variant gD protein is used for indirect ELISA, can be used for detecting whether a pseudorabies virus variant gD protein antibody exists in pig blood or not, and is simple, convenient and rapid in detection, high in specificity, high in sensitivity, accurate and reliable. The pseudorabies virus variant gD protein can be prepared into a subunit vaccine, can be induced to generate a high-level anti-pseudorabies virus variant neutralizing antibody after immunizing a pig, has the advantages of strong immunogenicity, high safety and matching with a current epidemic strain, can distinguish vaccine immunization and wild virus infection animals through differential diagnosis, and has a wide application prospect. The method can be used for preventing and controlling the propagation and prevalence of pseudorabies. The gD protein of the pseudorabies virus variant can be used for detecting and diagnosing pseudorabies and preventing pseudorabies, and has good production and application prospects in development of novel diagnostic reagents and subunit vaccines of pseudorabies viruses.

The invention provides an anti-varicella-zoster virus monoclonal antibody and an application thereof, relates to the technical field of monoclonal antibody screening and preparation, and more particularly relates to a monoclonal antibody which is obtained by immunizing mice through a recombinant varicella-zoster virus gE trimer protein vaccine. The monoclonal antibody for resisting the varicella-zoster virus is screened and prepared in a hybridoma mode, and the specific application of the antibody is provided. The recombinant VZV-gE tripolymer protein vaccine provided by the invention has good immunogenicity, and can induce higher immune serum titer. The human-mouse chimeric monoclonal antibody disclosed by the invention has good binding activity and affinity to the VZV-gE protein, and the indirect ELISA method for detecting the gE protein has good linear relation and detection limit, so that the human-mouse chimeric monoclonal antibody is expected to be used for VZV vaccine evaluation and VZV infection diagnosis.

The invention discloses an indirect ELISA kit for rapidly detecting a porcine epidemic diarrhea virus IgA antibody and application of the indirect ELISA kit, and belongs to the technical field of immunology. The invention provides a recombinant PEDV-RBD protein. The amino acid sequence of the recombinant PEDV-RBD protein is shown as SEQ ID NO. 3. The indirect ELISA kit for detecting the porcine epidemic diarrhea virus IgA antibody is constructed based on the recombinant PEDV-RBD protein, the PEDV IgA antibody in pig breast milk or serum can be accurately captured for detection, the kit has the advantages of high sensitivity and strong specificity, and a technical means is provided for prevention and control of porcine epidemic diarrhea.

The invention discloses a monoclonal antibody and application thereof in quantitative detection of porcine epidemic diarrhea virus, and belongs to the technical field of biological detection. The preparation method comprises the following steps: firstly, obtaining two monoclonal antibodies GC44F3-1 and GC32C11-5 which specifically react with S protein of the porcine epidemic diarrhea virus; secondly, establishing a double-antibody sandwich ELISA (Enzyme-Linked Immunosorbent Assay) method by taking the two monoclonal antibodies as a coating antibody and a detection antibody respectively, and applying the double-antibody sandwich ELISA method to PEDV (Porcine Epidemic Diarrhea Virus) vaccine S protein quantification; the method can be used for detecting semi-finished products and finished products, can be used for process establishment, optimization, vaccine quality evaluation and stability monitoring of porcine epidemic diarrhea virus vaccine antigens, has the advantages of high sensitivity, high accuracy, high repeatability and high flux, is high in detection flux and high in speed, solves the problem that TCID50 cannot meet vaccine quality evaluation at present, and has a good application prospect. The defect that the existing S protein ELISA method can only be used for qualitative judgment is overcome. The monoclonal antibody can also be used for blocking ELISA, capturing ELISA, indirect ELISA, competitive ELISA and a reagent for detecting the porcine epidemic diarrhea virus through a colloidal gold test strip.

The invention discloses an indirect ELISA (Enzyme-Linked Immunosorbent Assay) detection kit for distinguishing host infected Listeria monocytogenes and / or Listeria ivanovii. The coating antigens are respectively a recombinant listeria monocytogenes surface protein ActA, a serotype 4h listeria monocytogenes and listeria ivanovii common outer membrane protein SmcL and a listeria ivanovii specific outer membrane protein I-inlH, indirect ELISA methods are respectively established based on the three antigens, the three detection methods are combined to detect the content of the listeria monocytogenes, and the content of the listeria ivanovii can be detected. The levels of the ActA antibody, the SmcL antibody and the I-inlH antibody in a clinical serum sample can be effectively monitored, and the detection on the listeria monocytogenes caused by the listeria monocytogenes and / or the listeria ivanovii is realized. The kit is relatively high in sensitivity, strong in specificity and good in stability, and an effective method is provided for epidemiological investigation and diagnosis of listeria monocytogenes.

The invention provides human trichomonad antigen gene protein glyceraldehyde-3-phosphate dehydrogenase, and particularly relates to application of the protein in immunological detection of human trichomonad infection, the protein can be used for immunological detection of human trichomonad infection, and a human trichomonad detection kit is prepared. The GAPDH protein is used as a detection antigen for indirect ELISA detection, and the method has the characteristics of high sensitivity and specificity.

The invention discloses a type 2 GAstV capsid protein monoclonal antibody and an antigen epitope peptide of the type 2 GAstV capsid protein monoclonal antibody. The monoclonal antibody is prepared by immunizing a mouse with capsid protein GAstV Cap of the type 2 goose astrovirus as an antigen, and is named as 1F1; the monoclonal antibody 1F1 comprises a heavy chain variable region and a light chain variable region, and the amino acid sequences of the heavy chain variable region and the light chain variable region are sequentially shown as SEQ ID No.3 and SEQ ID No.5. In order to determine the B cell antigen epitope of the screened monoclonal antibody, the invention also constructs a GAstV Cap truncated fusion protein, and the antigen recognition epitope is determined through indirect ELISA and Western blotting tests, so that screening is carried out step by step until the shortest linear epitope recognized by the monoclonal antibody is determined, and the amino acid sequence of the shortest linear epitope is shown as SEQ ID No.10. Therefore, the monoclonal antibody and the antigen epitope of the monoclonal antibody can be applied to research on structures and functions of GAstV capsid proteins and preparation of serological diagnostic tools and epitope vaccines.

The invention relates to a biotechnology, and particularly discloses a soluble fibrous protein (SF) antibody and an application of the soluble fibrous protein antibody. According to the present invention, the single B cell antibody preparation technology and the flow cytometry sorting method are firstly applied to the blood coagulation in vitro diagnosis fibrinolysis system detection antibody development, and the mammalian cell expression system (293F) is adopted to successfully express and obtain the three strains of the SF monoclonal antibodies (the antibody numbers are SF-1, SF-2 and SF-3) with the biological activity; the three antibodies have specific reactions with SF, have no cross reactions with primary fibrinolytic substances (X, Y and D), can be applied to the fields of SF indirect ELISA and Western blotting detection and screening, make up the vacancy of domestic SF antibodies in the market, and realize fibrinolytic system detection integrity.

The present invention relates to an ELISA antibody detection method for serotype 2 Riemerella anatipestifer and an application thereof. The method is based on a bacterial lipopolysaccharide coated plate, and an indirect ELISA method for serotype 2 Riemerella anatipestifer is established through optimization of optimal reaction conditions, determination of critical values, specificity tests, sensitivity tests, repeatability tests and clinical trials. Compared with the prior art, the present invention extracts serotype 2 Riemerella anatipestifer lipopolysaccharide by hot phenol water method and coats the ELISA plate. By optimizing reaction conditions such as antigen coating conditions, dilution multiple and incubation conditions of serum to be tested / rabbit anti-duck enzyme-labeled antibodies, and substrate color development time, an indirect ELISA method for detecting serotype 2 Riemerella anatipestifer antibodies is successfully established.

The invention discloses an anti-soluble transferrin receptor monoclonal antibody as well as a preparation method and application thereof, and belongs to the technical field of antibody detection. According to the antibody, an L101-F760 amino acid sequence of human TfR protein is used as an immunogen, specific screening of B cells, reverse RNA (Ribonucleic Acid) into cDNA (Complementary Deoxyribose Nucleic Acid) through RT-PCR (Reverse Transcription-Polymerase Chain Reaction), then homologous recombination is performed to construct heavy and light chain vectors, and finally multiple rounds of screening are performed to obtain the purified sTfR monoclonal antibody, so that the sTfR protein can be specifically recognized, and the antibody has the advantages of high specificity and high sensitivity and can be widely applied to the field of immunotherapy. The natural sTfR protein in human serum can be recognized. The kit is applied to the detection and screening fields of immunohistochemistry, immunofluorescence chemistry, western blot, co-immunoprecipitation, indirect ELISA, flow cytometry and the like, especially has low background and no interference of non-specific binding impure protein during immunohistochemistry detection, can obtain more accurate detection and evaluation results, avoids interference of false positive and false negative, and has high detection accuracy. The method has great application value in the aspects of basic scientific research and clinical pathology detection.

The invention is applicable to the technical field of biology, and provides an L7 / L12-PADRE sequence-multi-linked B cell epitope recombinant protein and a kit for detecting an anti-Brucella antibody. The recombinant protein is a multi-epitope tandem recombinant protein composed of Brucella ribosome L7 / L12 protein, a PADRE polypeptide sequence and multiple B cell epitopes, the amino acid sequence of the recombinant protein is as shown in SEQ ID No.1, and the recombinant protein is good in antigenicity. The anti-brucella antibody indirect ELISA (iELISA) detection method and kit established by taking the recombinant protein as the coating antigen have the characteristics of high sensitivity, strong specificity and good repeatability, are suitable for detecting the condition of generating the anti-brucella antibody by an organism, can clarify the immune background of brucella infection or brucellosis vaccine, and can be used for detecting the brucella infection or brucellosis vaccine. Basic data is provided for prevention and control of the Brucella disease of humans and animals, and meanwhile, the kit is conveniently applied to large-scale sample detection and epidemiological monitoring.

The invention provides an infectious bronchitis virus antigen epitope fusion peptide, and the prepared antigen epitope fusion peptide can be used for preparing an antibody and can also be used as a coating antigen for preparing an indirect ELISA detection product. The amino acid sequence of the provided epitope fusion peptide is SEQ ID NO: 4. After antigen epitope analysis is performed on S1 protein of an infectious bronchitis virus strain through bioinformatics software, a plurality of antigen epitopes are fused to obtain the antigen epitope fusion peptide. Specificity tests show that the prepared antigen epitope fusion peptide is a coating antigen, does not have cross reaction with positive serum of other common pathogens, and only has good reaction with positive serum of GI-19 type IBV, that is, the antigen epitope fusion peptide has good serotype specificity as a detection antigen, and has small cross reaction with non-GI-19 type IBV antibody.

The invention discloses an indirect ELISA (enzyme-linked immuno sorbent assay) detection method of a porcine epidemic diarrhea virus antibody SIgA, and belongs to the technical field of animal antibody detection. In order to solve the problems of limited detection range and single immune evaluation dimension of a porcine epidemic diarrhea virus detection method in the prior art, the invention provides an indirect ELISA detection method of a porcine epidemic diarrhea virus antibody SIgA, and the detection method adopts a pichia pastoris eukaryotic secretion platform to prepare a high-activity PEDV S1 antigen; meanwhile, a secreting type IgA antibody is used as a detection target; the method has the advantages of high detection sensitivity, low background noise, better variant compatibility and practical popularization value, and provides a clinical and industrial-level solution for maternal immunity monitoring, piglet passive protection evaluation and vaccine immunity strategy optimization.

The invention discloses an EmAGO2 truncated recombinant protein, an echinococcosis multilocularis indirect ELISA (enzyme-linked immuno sorbent assay) diagnostic kit based on the truncated recombinant protein and a use method of the kit. The method comprises the following steps: designing a specific primer by selecting a sequence of 1-738bp at the N end of an Em-AGO2 gene, carrying out PCR (Polymerase Chain Reaction) amplification by taking reverse transcription echinococcosis multilocularis DNA (Deoxyribonucleic Acid) as a template, connecting an amplification product with a pCE2-TA / Blunt vector, and then transforming into a competent cell for culturing, so as to obtain a pCE2-T-EmAGO2 plasmid; respectively carrying out double enzyme digestion on the plasmid and an expression vector pET-28a (+), and connecting enzyme digestion fragments to obtain a recombinant protein expression plasmid pET-28a-EmAGO2; the preparation method comprises the following steps: taking EmAGO2 as a template, transforming the EmAGO2 into competent cells, selecting positive clones for induced expression, and carrying out ultrasonication treatment, separation and purification, concentration and desalination treatment on expressed thalli to obtain the EmAGO2 truncated recombinant protein. Furthermore, a mouse anti-EmAGO2 truncated recombinant protein and goat anti-rabbit IgG are respectively used as an antigen and an antibody to establish an indirect ELISA diagnostic kit for the echinococcosis multilocularis, and the kit has high sensitivity, specificity and good repeatability, and can be used for early diagnosis of the echinococcosis multilocularis.

The invention relates to the technical field of biological products, in particular to an indirect ELISA (Enzyme-Linked Immunosorbent Assay) detection kit and a detection method for a goose astrovirus antibody. The kit comprises an elisa plate, an elisa secondary antibody, goose astrovirus positive control serum, goose astrovirus negative control serum, a diluent, a washing solution, a developing solution and a stop solution, wherein a coating antigen of the ELISA plate is a goose astrovirus VP27 recombinant protein, the goose astrovirus is a goose astrovirus GAstV / SD / 36, and the goose astrovirus VP27 recombinant protein corresponds to an ORF2 region. The goose astrovirus GAstV / SD / 36 is used as a template, the virus antigen recognition site VP27 protein is selected as an antigen for preparing the indirect ELISA kit, the indirect ELISA detection kit of the goose astrovirus antibody is prepared, and the accuracy of the detection result of the kit can be improved.

The invention discloses a sheep paratuberculosis specific detection kit and application, and relates to the field of biological detection.The kit comprises an elisa plate coated with a recombinant Mycobacterium paratuberculosis membrane protein antigen, the nucleotide sequence of the recombinant Mycobacterium paratuberculosis membrane protein antigen is shown as SEQ ID NO: 1, and the amino acid sequence of the recombinant Mycobacterium paratuberculosis membrane protein antigen is shown as SEQ ID NO: 2; a confining liquid; a serum diluent; carrying out enzyme labeling on a second antibody; a TMB color developing solution and a stop solution; according to the sheep paratuberculosis specific detection kit disclosed by the invention, the recombinant Mycobacterium paratuberculosis membrane protein antigen is adopted as a core detection component, and the antigen has high specificity and can accurately identify paratuberculosis positive serum and effectively distinguish positive and negative samples; meanwhile, prokaryotic expression and purification are carried out on the specific membrane protein of the mycobacterium paratuberculosis for the first time, and a novel sheep paratuberculosis indirect ELISA diagnosis method with high sensitivity and specificity based on the protein as an antigen is established.

The invention discloses a porcine epidemic diarrhea virus S protein monoclonal antibody and application thereof. Specifically, two monoclonal antibodies GC42G2-1 and GC33D8-1 which have broad-spectrum binding characteristics with the porcine epidemic diarrhea virus S protein are obtained firstly, the GC42G2-1 antibody has good universality and can have strong affinity with different strains, and the GC33D8-1 antibody can be used for binding the porcine epidemic diarrhea virus S protein in a broad-spectrum manner. The GC42G2-1 can be independently used, and also can be matched with a polyclonal antibody or GC33D8-1 to be used for sandwich ELISA (enzyme-linked immunosorbent assay) so as to detect and quantify PEDV (porcine epidemic diarrhea virus). Secondly, the two monoclonal antibodies are respectively used as a coating antibody and a detection antibody, a double-antibody sandwich ELISA method is established, and the double-antibody sandwich ELISA method is applied to PEDV vaccine S protein quantification, has better parallelism compared with other antibodies, and can be widely applied to detection of different strains. The method disclosed by the invention has the advantages of high sensitivity, high accuracy, high repeatability and high flux, and can be used for the development of blocking ELISA (Enzyme-Linked Immunosorbent Assay), capturing ELISA, indirect ELISA, competitive ELISA and detection of porcine epidemic diarrhea viruses by colloidal gold test strips.

The invention discloses a recombinant CapA protein of cat astrovirus. The recombinant CapA protein has an amino acid sequence as shown in SEQ ID NO.1 in a sequence table or is coded by a base sequence as shown in SEQ ID NO.2 in the sequence table. Therefore, a cat astrovirus indirect ELISA antibody detection kit is developed and comprises a coated ELISA plate, and the coated ELISA plate takes the recombinant CapA protein as a coating antigen. Meanwhile, a corresponding indirect ELISA antibody detection method is established. Research results show that the critical value of the indirect ELISA antibody detection method and kit is 0.523; the sensitivity is 1: 32000; the in-batch variation coefficient of detected samples is 2.679%-7.910%, the inter-batch variation coefficient is 3.627%-8.982%, both the in-batch variation coefficient and the inter-batch variation coefficient are smaller than 10%, and the clinical application effect is good. Therefore, the kit has the characteristics of high sensitivity, strong specificity, good repeatability and the like, can quickly and effectively detect the FAstV antibody, and provides technical support for accurate diagnosis, timely prevention and control and vaccine effect evaluation of FAstV.

The invention discloses a method for establishing indirect ELISA (enzyme-linked immunosorbent assay) for detecting mycobacterium bovis Lprl, which comprises the following steps: preparing mycobacterium bovis Lprl protein, taking the purified protein as an antigen, and determining conditions such as optimal antigen coating concentration, serum dilution, serum incubation time, secondary antibody dilution concentration, incubation time and the like. The established indirect ELISA detection method does not have cross reaction with other bovine pathogens, the specificity is good, the detection accuracy is high, and the total coincidence rate of test results of intradermal allergy with bovine tubercle bacillus is 95.8%; the intra-batch variation coefficient of the detected samples is 2.43%-3.61%, the inter-batch variation coefficient is 2.83%-3.96%, and the intra-batch variation coefficient and the inter-batch variation coefficient are both smaller than 10%. A new diagnosis target is developed, the established indirect ELISA method has the characteristics of high sensitivity, strong specificity, good repeatability and the like, the operation is easy, and a new method is provided for the detection work of the mycobacterium bovis.

The invention discloses an indirect ELISA (Enzyme-Linked Immunosorbent Assay) kit for rapidly detecting a porcine delta coronavirus IgA antibody, and relates to the field of immunological detection. The indirect ELISA kit comprises an ELISA plate coated with an antigen, the antigen is a recombinant PDCoV S2 protein, and the amino acid sequence of the antigen is as shown in SEQ ID NO. 2. According to the indirect ELISA kit, a recombinant PDCoV S2 protein is used as a coating antigen to capture a PDCoV specific IgA antibody, a goat anti-pig IgA antibody labeled by horse radish peroxidase is used as a detection antibody, a 'PDCoV-S2 protein-PDCoV-S2 specific IgA antibody-enzyme labeled antibody' trimer compound can be formed on an ELISA plate, and the PDCoV specific IgA antibody-enzyme labeled antibody can be used for detecting the PDCoV specific IgA antibody. And the result can be directly judged by measuring the color change of the substrate and the absorbance value, so that the detection efficiency can be obviously improved. The indirect ELISA kit can be used for clinical detection and immune evaluation of the PDCoV.

The invention belongs to the technical field of biology, and particularly relates to a hybridoma cell strain capable of secreting a clostridium perfringens ETX monoclonal antibody with neutralizing activity and application of the hybridoma cell strain. On the basis of natural toxin, an indirect ELISA (enzyme-linked immunosorbent assay) detection method is established by utilizing a non-toxic ETX single amino acid site protein mutant, and a series of hybridoma cell strains secreting an anti-clostridium perfringens ETX monoclonal antibody are screened; the hybridoma cell strain can stably and efficiently secrete a monoclonal antibody with neutralizing activity and a monoclonal antibody without neutralizing resistance respectively, and large-scale batch production can be realized. According to the present invention, the clostridium perfringens ETX monoclonal antibody is firstly utilized to establish the ETX antigen ELISA detection method, and the method has characteristics of simple sample operation, low cost, rapid reaction, strong specificity and the like, can provide the reference for the diagnosis of clostridium perfringens, and provides the basis for the research of the related vaccine potency test substitution method.

The invention relates to the technical field of biology, in particular to an anti-porcine CD82 protein monoclonal antibody, a hybridoma cell strain and application, the monoclonal antibody is prepared by the following steps: expressing and purifying a CD82 (EC2) region by utilizing a prokaryotic expression system, preparing by taking the purified recombinant protein as an immunogen, and carrying out indirect ELISA (enzyme-linked immuno sorbent assay) and Flow Cytometry screening to obtain the monoclonal cell strain capable of secreting an IgG2a type antibody. The purified antibody is detected through an indirect ELISA method, sensitive reaction still exists when the antibody concentration reaches 31.25 ng / ml, PAM cells capable of expressing endogenous CD82 protein are detected through flow cytometry, and the result shows that the mAb has good marking capacity for the PAM cells, indicating that the mAb of the CD82 protein capable of being used for flow cytometry is successfully prepared. A biological tool is provided for further analyzing the function and mechanism of the CD82 protein.

The invention discloses a method for establishing duck hepatitis virus antibody ELISA (enzyme-linked immuno sorbent assay) detection, which comprises the following steps: firstly, preparing experimental materials, and then cloning and antigenicity analysis of structural genes, inducible expression of positive recombinants in escherichia coli, expression and purification of recombinant proteins, antigenicity analysis of the recombinant proteins and establishment of a recombinant antigen VP3 indirect ELISA method. Finally, VP0, VP3 and VP1 recombinant proteins can react with duck anti-DHV-1 positive serum and have good antigenicity, indirect ELISA results show that under the same coating concentration, the P / N value of the fusion protein GST-VP3 serving as a coating antigen is higher than that of the fusion protein GST-VP3 serving as the coating antigen and that of the fusion protein GST-VP3 serving as the coating antigen, it is indicated that the antigenicity of the fusion protein GST-VP3 is better than that of the fusion protein GST-VP3 serving as the coating antigen and that of the fusion protein GST-VP3 serving as the coating antigen and that of the fusion protein GST-VP3 serving as the coating antigen and that of the fusion protein GST-VP3 serving as the coating antigen and that of the fusion protein and the result is consistent with the prediction result.

A diagnostic kit for a confirmatory assay using the indirect ELISA method that measures the levels of anti-Native Hapten antibodies produced during a real infection, thereby preventing large financial losses to livestock farm, by discerning “false positives” that present anti-LPS antibodies due to cross-reactions with enterobacteria and post-vaccinal antibodies for the diagnosis of bovine brucellosis in blood serum and individual milk (per animal) and bulk milk (tank), characterised by using the crude Native Hapten antigen, extracted from B. melitensis 16M strain, with no purification treatment and an effective adherence capacity, which is used to antigenize plates at a known concentration (1 μg per well), where using as reference positive and negative controls subjected to the lyophilisation (freeze drying) method to ensure their preservation, thereby avoiding the contamination and degradation of the antibodies present and ensuring the stability of the optical densities in said controls for a correct results interpretation of an indirect ELISA, are taken as reference. The lyophilisation method for controls that may be used in other diagnostic methods is also presented.

The application belongs to the technical field of biology and particularly relates to an African swine fever virus pNP868R protein monoclonal antibody and a preparation method and application thereof. The application takes the pNP868R protein prepared by eukaryotic expression as an antigen, immunizes BALB / c mice, uses hybridoma technology, and obtains a hybridoma cell line capable of stably secreting the anti-African swine fever virus pNP868R protein monoclonal antibody through cell fusion, indirect ELISA method screening, limited dilution method subcloning and hybridoma continuous passage culture. The application also obtains an African swine fever virus pNP868R protein monoclonal antibody. The monoclonal antibody has high affinity with the pNP868R protein and can be applied in Western-Blot experiments, indirect immunofluorescence experiments, immunoprecipitation experiments and the capture of proteins interacting with pNP868R, and can be used for the diagnosis, prevention or treatment of African swine fever.

The invention discloses a detection method and a kit for detecting listeria monocytogenes, and relates to the technical field of biology. The kit is an indirect ELISA kit and comprises an elisa plate coated with an antigen, the amino acid sequence of the antigen is as shown in SEQ ID NO. 2. The indirect ELISA detection kit constructed by the invention only reacts with listeria monocytogenes positive serum, has no cross reaction with other serum, and has strong specificity; when the serum dilution is 1: 800, the detection result is still positive, and the sensitivity is high; the intra-batch variation coefficient ranges from 2.79% to 6.64%, the inter-batch variation coefficient ranges from 2.61% to 7.75%, and the intra-batch repeatability and the inter-batch repeatability are good; 24 serum samples are detected, and the total coincidence rate is 95.83%. The kit provided by the invention can effectively detect sample infection of Listeria monocytogenes, and has the advantages of strong specificity, high sensitivity and good repeatability.

The application relates to a detection method of anti-preS1 antibody, an anti-preS1 antibody detection kit and application, the application carries out multi-sequence comparison and conservation analysis on preS1 sequences of different genotypes (A, B, C, D and CD mixed type) of HBV, takes type A (AB697487.1), type C (FJ032351.1) and type D (LC519808.1) as reference sequences, based on the sequence consistency standard of 85% of full length and 90% of the key region of functional antibody binding, a highly conservative preS1 full-length antigen sequence is systematically screened out in natural variation, the sequence can cover antigen variation of A-D type HBV, and the sequence is taken as a coating antigen to establish an indirect ELISA detection system, a good linear relationship is presented in the range of 4.88-625 ng / mL, and the Cut-off value is 33.6 ng / mL; clinical verification shows that the method can effectively distinguish chronic hepatitis B patients from healthy control groups, compared with detection methods based on partial fragments or overlapping short fragments, the false negative rate can be significantly reduced, and the method is suitable for HBV infection immune state evaluation, anti-virus curative effect monitoring and prognosis analysis.

The invention provides an indirect ELISA antibody detection method based on African swine fever virus D250R protein, and relates to the technical field of virus detection. The method comprises the following steps: cloning a D250R protein gene into a prokaryotic expression vector pET-32a (+) to construct a recombinant plasmid pET-32a-D250R, inducing a D250R recombinant protein through IPTG (isopropyl-beta-d-thiogalactoside), purifying the recombinant protein and coating an elisa plate, and optimizing and determining the optimal conditions of indirect ELISA (Enzyme-Linked Immunosorbent Assay). On the basis of the D250R protein, serum to be detected is taken as a sample, and the established indirect ELISA antibody detection method is high in sensitivity, strong in specificity and high in coincidence rate with a commercialized kit, and provides reference for development and prevention and control of an ASF diagnosis technology.

The present invention belongs to the field of biomedicine technology, and discloses a specific epitope polypeptide, a kit and an application thereof. The present invention provides a SARS-CoV-2 specific epitope polypeptide associated with neutralizing activity, and its amino acid sequence is shown in SEQ ID No.2. The present invention designs and constructs a SARS-CoV-2 polypeptide microarray, analyzes the IgG and IgM antibody responses induced by the SARS-CoV-2 inactivated vaccine, screens out a series of immune epitope polypeptides associated with the neutralizing activity of antibodies, and establishes a polypeptide indirect ELISA detection kit on this basis. The method has high sensitivity, good specificity, good repeatability and stability, and does not require a high-level biosafety laboratory. It is easy to operate, objective in judging the results, and can achieve the purpose of quickly evaluating the level of new crown vaccine antibodies, providing new means and directions for new crown antibody detection methods.