Preparation method and application of Qbeta-2aa phage virus-like particle protein

Abstract

The invention relates to a Qbeta-2aa phage virus-like particle protein which is prepared according to a method comprising the following steps of: (1) mutating a Qbeta phage CP (coat protein) gene terminator codon into a strong terminator codon TAA from TGA and then cloning the strong terminator codon into a protokaryon expression vector pET28a(+) to obtain a coding CP plasmid pETQB-CP; (2) inserting the nucleotides AAGCTT of coding lysine and leucine at the coding immunodominance determining region position in a Qbeta phage CP extension protein gene, i.e. between the 72th codon and the 73th codon of the Qbeta phage CP extension protein gene, and mutating the CP gene terminator codon into GGA from TGA and then cloning the GGA into a protokaryon expression vector PGEX4T-2 to obtain a codingA1 protein plasmid pGEXQbeta-A1; (3) jointly converting the mutated coding Qbeta phage CP plasmid and the A1 protein plasmid into escherichia coli, and inducing and then expressing to obtain the virus-like particle protein Qbeta-2aa; and (4) coupling a short peptide antigen to Qbeta-2aa phage virus-like particles by using a iso-bifunctional cross-linking agent.

Description

technical field [0001] The invention belongs to the fields of biotechnology medicine and biotherapeutics, and relates to the construction of a vaccine carrier for immune targeting therapy and a method for coupling the carrier with a short peptide. Background technique [0002] Therapeutic vaccines for chronic diseases are currently the focus of vaccine research. These diseases include: chronic viral infections, allergic diseases, tumors, diabetes, hypertension, and Alzheimer's disease. Good effect and broad application prospect. The difference from ordinary preventive vaccines is that therapeutic vaccines are aimed at self-antigens or foreign immune tolerance antigens. Therefore, in order to play a therapeutic role, therapeutic vaccines must first break immune tolerance and produce autoantibodies or self-reactions against specific antigens. T cells. Since the target antigens of therapeutic vaccines are generally short peptides with weak antigenicity, they must be combined ...

AI Technical Summary

Problems solved by technology

Although the virus-like particle itself is not infectious, the virus that can infect the human body may have a cross-reaction with human tissue, and autoimmune diseases such as myocarditis may occur after immunization, and if the body has been infected with the virus, the immune effect of the carrier will be Weakened, thus unable to exert therapeutic effect

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