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CN-122011164-A - Hepatitis B virus monoclonal antibody SY-4 and preparation and application thereof

CN122011164ACN 122011164 ACN122011164 ACN 122011164ACN-122011164-A

Abstract

The invention discloses a hepatitis B virus monoclonal neutralizing antibody SY-4, and preparation and application thereof. The hepatitis B virus monoclonal neutralizing antibody is SY-4, and consists of a heavy chain and a light chain matched with the heavy chain, wherein the amino acid sequences of CDR1, CDR2 and CDR3 of the heavy chain of the SY-4 are DFSFSSHA, ISYDGGTT and AKEGNAFRYFGWLPDYQYFGMDV in sequence, and the amino acid sequences of CDR1, CDR2 and CDR3 of the light chain are QRINRY, AAS and QQYGNSPLCS in sequence. The hepatitis B virus monoclonal neutralizing antibody SY-4 is a strain of HBV neutralizing antibody, has ADCP activity, can cross-identify various HBV genotypes HBsAg, has good biological functions, and provides a new candidate antibody for preventing and treating hepatitis B virus.

Inventors

  • JU BIN
  • ZHANG ZHENG
  • GE XIANGYANG
  • YAN HU
  • ZHOU BING
  • LI YUXIAO

Assignees

  • 深圳市第三人民医院(深圳市肝病研究所)

Dates

Publication Date
20260512
Application Date
20260206

Claims (10)

  1. 1. The monoclonal neutralizing antibody for the hepatitis B virus is SY-4 and consists of a heavy chain and a light chain matched with the heavy chain, wherein the amino acid sequences of CDR1, CDR2 and CDR3 of the heavy chain are DFSFSSHA, ISYDGGTT and AKEGNAFRYFGWLPDYQYFGMDV in sequence, and the amino acid sequences of CDR1, CDR2 and CDR3 of the light chain are QRINSY, AAS and QQYGNSPLCS in sequence.
  2. 2. The monoclonal antibody of claim 1, wherein the heavy chain variable region sequence of SY-4 is the sequence shown in Seq ID No.1 and the light chain variable region sequence is the sequence shown in Seq ID No. 2.
  3. 3. A nucleic acid fragment encoding the monoclonal neutralizing antibody to hepatitis b virus of claim 1 or 2, wherein the nucleic acid fragment encodes the heavy and light chains of SY-4.
  4. 4. The nucleic acid fragment according to claim 3, wherein the nucleic acid fragment comprises a nucleic acid sequence encoding a heavy chain variable region represented by Seq ID No.1, the sequence of which is represented by Seq ID No.3, and a nucleic acid sequence encoding a light chain variable region represented by Seq ID No.2, the sequence of which is represented by Seq ID No. 4.
  5. 5. A recombinant plasmid comprising the nucleic acid fragment of claim 3 or 4.
  6. 6. A recombinant cell comprising the nucleic acid fragment of claim 3 or 4 or the recombinant plasmid of claim 5.
  7. 7. The method for preparing the hepatitis B virus monoclonal neutralizing antibody according to claim 1 or 2, which is characterized by comprising the steps of carrying out protein expression on the recombinant plasmid according to claim 5 by adopting the recombinant cell according to claim 6, extracting and purifying the expressed protein, and obtaining the hepatitis B virus monoclonal neutralizing antibody.
  8. 8. Use of the monoclonal neutralizing antibody against hepatitis b virus according to claim 1 or 2, or the nucleic acid fragment according to claim 3 or 4, or the recombinant plasmid according to claim 5, or the recombinant cell according to claim 6, for the preparation of a medicament for controlling hepatitis b virus or a reagent for detecting hepatitis b virus.
  9. 9. A hepatitis b virus controlling drug comprising the hepatitis b virus monoclonal neutralizing antibody according to claim 1 or 2, or a substance capable of inducing the production or in vivo expression of the hepatitis b virus monoclonal neutralizing antibody according to claim 1 or 2.
  10. 10. A hepatitis b virus detection reagent comprising the hepatitis b virus monoclonal neutralizing antibody according to claim 1 or 2, or an antigen capable of specifically binding to the hepatitis b virus monoclonal neutralizing antibody according to claim 1 or 2.

Description

Hepatitis B virus monoclonal antibody SY-4 and preparation and application thereof Technical Field The application relates to the technical field of HBV neutralizing antibodies, in particular to a hepatitis B virus monoclonal antibody SY-4, and preparation and application thereof. Background Hepatitis b virus (HEPATITIS B VIRUS, HBV) infection remains a global significant public health problem. Chronic HBV infection can lead to a range of liver diseases such as chronic viral hepatitis b (chronic hepatitis B, CHB), cirrhosis (liver cirrhosis, LC), and primary hepatocellular carcinoma (hepatocellular carcinoma, HCC). There are two major classes of drugs currently approved by the FDA for the treatment of chronic hepatitis b, interferon and nucleoside analogs, which act as antiviral agents by modulating host immunity and inhibiting viral replication, respectively. The existing medicine has very strong safety and antiviral activity, but has very limited treatment effect. The negative conversion rate of the HBsAg of the medicines is less than 5%, and the clinical cure cannot be realized. Therefore, there is a need to develop more effective new drugs to improve clinical management of HBV-related diseases. The antibody plays an important role in preventing organism infection, helping organism remove viruses and the like, and can be used as a natural specific drug to be applied to the treatment research of chronic hepatitis B. Antibodies targeting viral surface antigens can on the one hand utilize Fab regions to prevent virus entry into hepatocytes by blocking the interaction of hepatitis b virus with pro-receptor HSPG, or to prevent a new round of viral infection by the antibody being endocytosed into hepatocytes followed by blocking release of hepatitis b virus from the infected cells. On the other hand, antibodies can also interact with phagocytes through the Fc region, mediating clearance of the antigen-antibody immune complex, i.e., the ADCP effect of the antibody. Although the traditional Hepatitis B Immunoglobulin (HBIG) is widely applied clinically, the traditional hepatitis B immunoglobulin is mainly derived from hepatitis B vaccine inoculator serum with higher antibody titer, the yield is low, and the antibodies from different batches have larger difference in concentration and titer. Therefore, there is a need to develop anti-hepatitis B virus monoclonal antibodies with higher titers and better specificity, and provide new means for treating chronic hepatitis B. Disclosure of Invention The invention aims to provide a hepatitis B virus monoclonal antibody SY-4, and preparation and application thereof. In order to achieve the above purpose, the present invention adopts the following technical scheme: The first aspect of the invention discloses a hepatitis B virus monoclonal neutralizing antibody, which is SY-4 and consists of a heavy chain and a light chain matched with the heavy chain, wherein the amino acid sequences of CDR1, CDR2 and CDR3 of the heavy chain are DFSFSSHA, ISYDGGTT and AKEGNAFRYFGWLPDYQYFGMDV in sequence, and the amino acid sequences of CDR1, CDR2 and CDR3 of the light chain are QRINSY, AAS and QQYGNSPLCS in sequence. It should be noted that the key point of the present invention is that the clone-amplified plasmablasts are isolated from Peripheral Blood Mononuclear Cells (PBMCs) collected on day 7 after vaccination, and finally a fully human monoclonal neutralizing antibody, SY-4, is obtained, which has cross-binding activity and antiviral function with different HBV genotype HBsAg proteins. In one implementation of the invention, the heavy chain variable region sequence of the hepatitis B virus monoclonal neutralizing antibody SY-4 is the sequence shown by the Seq ID No.1, and the light chain variable region sequence is the sequence shown by the Seq ID No. 2. It should be noted that the heavy chain variable region and the light chain variable region of the above specific sequences are only monoclonal neutralizing antibody sequences specifically employed in one embodiment of the present invention, and it is understood that the regions affecting the formation of precise complementarity with an epitope are complementarity determining regions (abbreviated CDRs) for monoclonal neutralizing antibodies, specifically, CDR1, CDR2 and CDR3 of the heavy chain and CDR1, CDR2 and CDR3 of the light chain, and thus, the functions and actions of the monoclonal neutralizing antibody against hepatitis b virus of the present invention can be basically achieved as long as the sequences of CDR1, CDR2 and CDR3 of the heavy chain and light chain of the present invention are ensured to be unchanged. That is, the specific sequences of the monoclonal antibody against hepatitis B virus of the present invention are not limited to the heavy chain variable region and the light chain variable region of the above specific sequences. In a second aspect, the invention discloses a nucleic acid fragment encoding the hepati