CN-122012408-A - Monoclonal antibody of swine CD163 protein and application thereof

Abstract

The invention provides a monoclonal antibody for detecting swine CD163 protein and a corresponding epitope peptide. Wherein the hybridoma cell strain for preparing the monoclonal antibody is CCTCC NO: C2025258. The monoclonal antibody provided by the invention has good specificity, good affinity with pCD163 and definite epitope information. The antibody can remarkably inhibit the infection efficiency of strains of each PRRSV lineage in alveolar macrophages, has good PRRSV in-vitro blocking effect, can be used for developing a pCD163 detection reagent with high specificity, and is expected to be used as a candidate medicament for passive immune prevention and treatment of PRRS.

Inventors

• ZHOU LEI
• YANG HANCHUN
• FANG XINYU
• WU WEIXIN
• ZHOU QIONGQIONG
• GAO PENG
• ZHANG YONGNING
• GAI XINNA
• HAN JUN
• GUO XIN

Assignees

• 中国农业大学

Dates

Publication Date

20260512

Application Date

20260228

Claims (10)

1. 1. A hybridoma cell strain is characterized in that the preservation number of the hybridoma cell strain is CCTCC NO: C2025258.
2. 2. Use of the hybridoma cell line of claim 1 for the preparation of monoclonal antibodies.
3. 3. A monoclonal antibody, characterized in that, the monoclonal antibody is prepared by using the hybridoma cell strain according to claim 1.
4. 4. Use of the monoclonal antibody of claim 3 in the preparation of a reagent for detecting pCD163 protein.
5. 5. The use according to claim 4, wherein the agent is a preparation for western blot, immunohistochemical or immunofluorescent detection.
6. 6. A reagent for detecting pCD163 protein, wherein the reagent comprises the monoclonal antibody of claim 3.
7. 7. A method for detecting pCD163 protein in a sample, wherein the method uses the monoclonal antibody of claim 3.
8. 8. Use of the monoclonal antibody of claim 3 in the manufacture of a medicament for blocking porcine reproductive and respiratory syndrome virus.
9. 9. An epitope peptide, which is characterized in that the amino acid sequence of the epitope peptide is DPSSSI.
10. 10. The use of the epitope peptide of claim 9 in the preparation of a preparation for detecting swine CD 163.

Description

Monoclonal antibody of swine CD163 protein and application thereof Technical Field The invention belongs to the technical field of biological product preparation, and in particular relates to an epitope peptide of a swine CD163 protein, a hybridoma cell strain and a monoclonal antibody. Background The porcine reproductive and respiratory syndrome (Porcine reproductive and respiratory syndrome, PRRS) seriously jeopardizes the healthy development of the global pig industry, and the pathogenic Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) has high genetic variability, and the sequence differences among different genotypes and subtypes are obvious, so that the cross protection effect of the existing vaccine and antiviral prevention and control measures is limited. Current studies indicate that PRRSV has strict cell tropism, porcine CD163 (pCD 163) is a receptor necessary for PRRSV to infect target cells, with the SRCR5-9 domain of CD163 being a critical functional region that mediates viral entry into cells. Therefore, targeting the pCD163 key domain to block PRRSV invasion is considered an antiviral strategy with potential broad-spectrum application prospects. CD163, a member of the scavenger receptor cysteine rich (SCAVENGER RECEPTOR CYSTEINE-rich, SRCR) protein superfamily, is a membrane receptor that binds the globin-hemoglobin (Hp-Hb) complex and mediates the endocytosis of Hp-Hb by macrophages and eliminates the hemoglobin released during hemolysis, thereby preventing oxidative damage caused by heme iron. The extracellular region of pCD163 comprises 9 repeated SRCR domains (SRCR 1-SRCR 9) and 2 motifs rich in proline-serine-threonine (PST), where PSTI consists of 35 amino acids between SRCR6 and SRCR7 and PSTII consists of 16 amino acids connecting SRCR9 with the transmembrane region and cytoplasmic tail. The current prevention and control measures of PRRSV depend on biological safety isolation and improved live virus (Modified Live Virus, MLV) vaccines with safety risks, and MLV can successfully induce protective immune response to homologous viruses, but still has the problem of insufficient heterologous cross protection, and the MLV also has the safety problems of infection, transmission, immunosuppression, virulence return, gene recombination and the like. Subunit vaccines are better in safety, but the protective antigens of PRRSV are still in great debate, and the genetic variation diversity of viral antigens, which results in an unreliable immune protection effect of such vaccines. The current products can not meet the clinical demands, so that epitope peptides which have good immunogenicity, strong specificity and stable structure and can effectively block PRRSV infection are obtained from the pCD163 key functional structural domain in a screening way, and specific monoclonal antibodies are prepared according to the epitope peptides, so that a new technical approach and theoretical basis are provided for developing a broad-spectrum antiviral prevention and control strategy aiming at PRRSV. Disclosure of Invention The invention aims to provide a monoclonal antibody of porcine CD163 protein capable of blocking PRRSV infection and a corresponding epitope peptide. The monoclonal antibody is used for indirect immunofluorescence and Western blotting detection, analyzes the expression and distribution of pCD163 in alveolar macrophages and over-expression cells, provides a favorable tool for further researching the interaction mechanism of structural protein and CD163 in the PRRSV infection process, simultaneously provides a monoclonal antibody with broad-spectrum anti-PRRSV activity, and provides a new medicament for preventing and controlling PRRS. The invention firstly provides a hybridoma cell strain which is hybridoma cell strain 1E5 (Hybridoma cell line E5), wherein the preservation number is CCTCC NO: C2025258, the preservation time is 2025 years, 9 months and 5 days, the preservation unit is China center for type culture Collection, and the preservation address is China university of Wuhan. In another aspect, the invention provides a monoclonal antibody that specifically binds to pCD163 protein, said monoclonal antibody being produced by said hybridoma cell line. The invention provides an antigen epitope peptide recognized by the monoclonal antibody, which has an amino acid sequence of DPSSSI (SEQ ID NO: 1). The invention also provides application of the monoclonal antibody in preparing a reagent for detecting pCD163 protein. The reagent is a preparation for Western blotting, immunohistochemistry or immunofluorescence detection. The invention also provides a reagent for detecting the pCD163 protein, which comprises the monoclonal antibody. The invention also provides a method for detecting the pCD163 protein in a sample, which comprises the step of detecting the pCD163 protein by using the monoclonal antibody. In one embodiment, the sample is selected from lysates of 293T cells. The i