A型副鸡禽杆菌HMTP210和aroA亚单位疫苗免疫保护研究OA

To develop a subunit vaccine with good immunogenicity against Avibacterium paragallinarum serotype A,the genomic DNA of the Avibacterium para gallinarum HP-8 strain was used as a template to clone the HMTP210 and aroA genes.The HMTP210 gene sequence was optimized,and an Escherichia coli expression system was constructed to express recombinant HMTP210 and aroA proteins.After purifying the proteins using chromatography,subunit vaccines were prepared.Thirty-day-old SPF chickens were immunized with the two single-protein subunit vaccines and nine combi-nation vaccines.Antibody levels were measured 21 days post-immunization,and a challenge test was conducted for evalu-ation.The results showed successful expression of recombinant HMTP210 and aroA proteins with good solubility.Fol-lowing purification by ion-exchange chromatography,the protein purity reached 62％ and 92％,respectively.The protec-tive efficacy of the HMTP210 subunit vaccine and aroA subunit vaccine against Avibacterium paragallinarum serotype A was 70％ and 40％,while the combined vaccines achieved up to 100％ protection.This study indicates that the formula-ted combination vaccine shows favorable protective effectiveness,providing an experimental foundation for the develop-ment of subunit vaccines against infectious coryza.