12 results about "Antibody negative" patented technology

The invention provides an antigen epitope peptide related to connexin and application of the antigen epitope peptide. The connexin antigen epitope peptide disclosed by the invention is selected from (1) a polypeptide with an amino acid sequence as shown in SEQ ID NO: 14; and (2) a polypeptide which is derived from (1) by substituting, deleting or adding 1-2 amino acids in the amino acid sequence of SEQ ID NO: 14 and retains the binding capacity with a connexin antibody. According to the present invention, the new connexin antigenic peptide fragment sequence is identified for the first time, such that the existing autoantigen epitope map is expanded, and more importantly, the molecular basis is provided for the development of the clinical detection method with high diagnosis sensitivity and high specificity, such that the pathological mechanism of MG can be further improved, and the application prospect is broad. And new auxiliary diagnosis means and treatment targets are provided for antibody negative MG patients.

The present invention includes a method and kit for method for detecting anti-Ro antibody negative Sjögren's syndrome / Sjögren's disease without performing a lip biopsy comprising: obtaining a biological sample from a patient suspected of having an anti-Ro antibody negative Sjögren's syndrome / Sjögren's disease; and detecting if the biological sample has autoantibodies to at least one of: Geminin DNA Replication Inhibitor (GMNN), Kelch Domain Containing 8 A (KLHDC8A), Microtubule Associated Protein RP / EB Family Member 1 (MAPRE1), Nucleoporin 50 (NUP50), or SKI Like Proto-Oncogene (SKIL).

The invention belongs to the technical field of veterinary diagnosis, and particularly relates to a novel duck reovirus agar diffusion antigen as well as a preparation method and application thereof. The preparation method comprises the following steps: inoculating a novel duck reovirus GX2022 strain to an SPF (specific pathogen free) duck embryo at the age of 6-10 days, harvesting and inoculating a diseased duck embryo body within 24-144 hours, adding sterile normal saline, fully grinding, freezing and thawing (freezing at the temperature of-20 DEG C and thawing at the temperature of 25 DEG C), carrying out solid-liquid separation, collecting supernate, adding formaldehyde for inactivation, uniformly mixing the inactivated virus liquid with a freeze-drying protective additive, and freeze-drying to obtain the agar diffusion antigen. Compared with the prior art, the method has the advantages that the agar diffusion titer is as high as 1: 24, the specificity is strong, the stability is good, the titer is high, the yield is high, the reaction precipitation line is clear, the detection is convenient, the method can be used for evaluating the immune effect of the NDRV and diagnosing the infection of the NDRV, can also be used for screening NDRV antibody negative ducks, detecting exogenous virus antibodies of waterfowl live vaccines or virus seeds, performing epidemiological investigation and the like, and has a wide application prospect.

The application discloses application of anti-PCCB antibody in preparation of a diagnostic product for Sjogren's syndrome (SS), and the diagnostic product comprises a reagent for detecting the anti-PCCB antibody. It is found that the anti-PCCB antibody in serum and plasma of SS patients is significantly increased, the sensitivity of the anti-PCCB antibody as a biomarker for diagnosing SS is 32.89%, the specificity is 91.82%, and the anti-PCCB antibody has a significant diagnostic value. In anti-SSA antibody negative SS patients, the positive rate of the anti-PCCB antibody is 23.08%, and in anti-SSB antibody negative SS patients, the positive rate of the anti-PCCB antibody is 34.65%. In addition, the anti-PCCB antibody combined with the anti-SSA antibody / anti-SSB antibody also has good diagnostic value. The application further provides a PCCB polypeptide which can effectively recognize the anti-PCCB antibody in biological samples of SS patients, provides more choices for SS diagnosis, and fills the blank of the anti-SSA antibody and the anti-SSB antibody diagnosis.

The application belongs to the technical field of biology and particularly relates to a bovine viral diarrhea virus NS2 truncated protein and application thereof in BVDV antibody detection. The application provides a truncated protein of BVDV NS2 protein. The truncated protein is soluble expressed after being fused with glutathione S transferase (GST) and horseradish peroxidase (HRP) respectively, has good reactivity with BVDV antibody positive serum, does not react with BVDV antibody negative serum, and can be used for BVDV antibody detection. Furthermore, the application constructs a double antigen sandwich ELISA method for BVDV antibody detection by taking the fusion protein of GST and the truncated protein as a coating antigen and taking the fusion protein of HRP and the truncated protein as a detection antigen. The method has the technical advantages of high sensitivity, good specificity, simple operation, easy popularization, low cost and the like, and can be applied to screening of BVDV antibodies in a cattle herd.

This disclosure provides recombinant fusion proteins for use in relation to the novel coronavirus (COVID-19), comprising a SARS-CoV-2 nucleocapsid protein (N-protein) fragment or an analogue linked to a human Fc fragment. Multiple embodiments include administration of the fusion protein as a booster vaccine to patients recovering from COVID-19, administration to antibody-naive patients to produce antibodies against the SARS-CoV-2 virus so that the patient can become a convalescent plasma donor, administration to patients infected with the SARS-CoV-2 virus and suffering from COVID-19 to limit the scope of infection and improve the disease, and administration as a prophylactic COVID-19 vaccine. Exemplary Fc fusion proteins and pharmaceutical formulations of exemplary Fc fusion proteins are provided in addition to methods of use and preparation.

The present disclosure provides a recombinant prepared fusion protein comprising an SARS-CoV-2 nucleocapsid protein (N protein) fragment linked to a human Fc fragment, or an analog thereof, for use in association with a 2019 novel coronavirus (COVID-19). Embodiments include administering the fusion protein to a patient having recovered from COVID-19 as a booster vaccination, administering to an antibody-negative patient to produce an antibody against the SARS-CoV-2 virus to make the patient become a plasma donor for recovery, administering to a patient having infected with the SARS-CoV-2 virus and having contacted with COVID-19 to limit the range of infection and ameliorate disease, and administering to an antibody-negative patient to produce an antibody against the SARS-CoV-2 virus to make the patient become a plasma donor for recovery. And as a prophylactic COVID-19 vaccine. Exemplary Fc fusion proteins and pharmaceutical formulations of the exemplary Fc fusion proteins are provided in addition to methods of use and preparation.

The invention provides a biomarker combination for in-vitro diagnosis of membranous nephropathy. The biomarker combination comprises non-classical mononuclear cells, CD4 + T cells, effector CD4 + T cells, 2-type helper T cells, double-negative T cells, central memory CD4 + T cells, plasma cell-like dendritic cells, antibody secreting cells, total T cells, unconverted memory B cells, classical mononuclear cells and natural killer cells. The invention also provides a construction method of the membranous nephropathy diagnosis model. The construction method comprises a step of screening the characteristic biomarkers and a step of constructing the diagnosis model and evaluating the performance. According to the method, the optimal marker combination is screened out from the high-dimensional flow cytometry data by applying a random forest recursive feature elimination algorithm, and a random forest diagnosis model is constructed. The invention shows excellent performance in distinguishing membranous nephropathy patients from healthy controls, and shows high accuracy in independent verification including a diagnosis difficulty subgroup of PLA2R antibody negative.

The application provides a biomarker for idiopathic inflammatory myopathy and application thereof, and the biomarker is an anti-HDGFL1 antibody. The application further discloses application of the anti-HDGFL1 antibody as the biomarker for the idiopathic inflammatory myopathy, application of an anti-HDGFL1 antibody detection agent in preparation of a product related to diagnosis of the idiopathic inflammatory myopathy, a kit and a system for diagnosing the idiopathic inflammatory myopathy, evaluating a prognosis of a patient with the idiopathic inflammatory myopathy, or determining a type of the idiopathic inflammatory myopathy. The application realizes effective diagnosis, treatment, prognosis evaluation and disease typing for a patient with idiopathic inflammatory myopathy who is specific to serum myositis and negative to an autoantibody through the anti-HDGFL1 antibody.

The application provides a biomarker combination for in vitro diagnosis of membranous nephropathy, comprising non-classical monocytes, CD4+ T cells, effector CD4+ T cells, type 2 helper T cells, double negative T cells, central memory CD4+ T cells, plasmacytoid dendritic cells, antibody-secreting cells, total T cells, unswitched memory B cells, classical monocytes and natural killer cells. The application also provides a method for constructing a membranous nephropathy diagnosis model, comprising a step of screening characteristic biomarkers and a step of constructing and evaluating the performance of a diagnosis model. The application screens the optimal marker combination from high-dimensional flow cytometry data by applying a random forest recursive feature elimination algorithm, and constructs a random forest diagnosis model. The application shows excellent performance in distinguishing membranous nephropathy patients from healthy controls, and demonstrates high accuracy in independent verification including a difficult-to-diagnose subgroup of PLA2R antibody-negative patients.

The application discloses application of an antigen peptide MG15 and an antibody thereof in preparation of a rheumatoid arthritis diagnosis product, and belongs to the technical field of disease diagnosis. The application aims to solve the problem of lack of a serological diagnosis marker with high sensitivity and high specificity for RA (especially anti-CCP antibody negative RA), and relevant detection products show significant diagnostic value. The antigen peptide MG15 has an amino acid sequence of GNSSESESKTTHAYT or BSA-C-GNSSESESKTTHAYT, and is used for detecting the content of an epitope antibody capable of being specifically recognized by the antigen peptide MG15 in a biological sample of a patient. The epitope antibody has obvious differences between RA patients, healthy people and other easily-confused rheumatism and immunological disease patients, has a sensitivity of 47.47% and a specificity of 90.16% in serum RA diagnosis, can effectively identify and diagnose RA, and has unique diagnostic value in anti-CCP antibody negative RA patients.