Genetically-engineered lactobacillus oral vaccine strain for targeted delivery of vaccine antigens and application thereof in preventing and treating chicken colibacillosis

Abstract

The invention discloses a genetically-engineered lactobacillus oral vaccine strain for targeted delivery of vaccine antigens and application thereof in preventing and treating chicken colibacillosis.The genetically-engineered lactobacillus oral vaccine strain for targeted delivery of vaccine antigens is made by transferring chicken pathogenic Escherichia coli ompC protein and fimA protein and anexpression vector for a fusion protein of a targeting peptide, which targets at M cells and DC cells, to lactobacillus, wherein the ompC protein and fimA protein are connected through a flexible sequence, and a connection sequence of the fusion protein is ompC-fimA-M cell targeting peptide-DC cell targeting peptide. The ompC protein and fimA protein of chicken pathogenic Escherichia coli are usedas immunogens fused with the targeting peptide that may target at M cells and DC cells, lactobacillus is used as an antigen transfer vector, and genetically-engineered lactobacillus subunit oral vaccine for targeted delivery of vaccine antigens, which prevents chicken pathogenic Escherichia coli, is constructed; the genetically-engineered lactobacillus oral vaccine strain is effective in inhibiting infections of chicken pathogenic Escherichia coli, is convenient and safe to use and is environmentally friendly.

Description

technical field [0001] The present invention relates to a recombinant lactic acid bacteria vaccine strain and its preparation method and use, in particular to a genetically engineered lactic acid bacteria subunit oral vaccine strain for targeted delivery of vaccine antigens, its preparation method and its use in the prevention and treatment of chicken colibacillosis. The invention belongs to the technical field of medicine. Background technique [0002] Avian colibacillosios (avian colibacillosios) is a general term for various clinical disease types caused by avian pathogenic Escherichia coli (APEC) infecting poultry. Inflammation, salpingitis, enteritis, peritonitis and E. coli granuloma. There are many serotypes of pathogenic Escherichia coli, and the antigen structure is complex. Drug prevention and treatment is an important measure for the treatment of the disease, but widespread drug resistance of the epidemic strains brings difficulties to the prevention and control ...

AI Technical Summary

Problems solved by technology

Although a certain immune effect has been obtained, nodules are easily formed at the injection site after immunization, and the absorption is not complete. The stress response to the immunized chickens is large, which affects the meat quality and growth. At the same time, from the perspective of food safety and hygiene, oil adjuvant Residues in animals have potential impact on food safety

In addition, various antibacterial drugs are often used in the treatment of E. coli infection, resulting in the emergence of drug-resistant strains of E. coli and the continuous expansion of the drug resistance spectrum, forming a vicious circle. At the same time, it also exacerbates the residue of antibacterial drugs in livestock and poultry, affecting food safety.

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