Cross-Protective Efficacy of Recombinant Transferrin-Binding Protein A of Haemophilus parasuis in Guinea Pigs

• DOI: 10.1128/cvi.00621-12
• Publication Date: 2013-04-25T01:11:17Z
• Authors: Xiaohui Huang; Yu Li; Yuguang Fu; Yanhong Ji; Kaiqi Lian; Haixue Zheng; Jianzhong Wei; Xuepeng Cai; Qiyun Zhu
• Keywords: Heterologous; Booster dose

The causative agent of Glasser's disease in swine is Haemophilus parasuis. Commercial bacterins are widely used for protection the population. However, cross limited because H. parasuis has more than 15 serovars. Transferrin-binding protein A shown potential as a broad-spectrum vaccine candidate against homologous and heterologous strains. Here we amplified full-length tbpA gene from an serovar 13 isolate cloned it into pET-SUMO expression vector. We then expressed purified TbpA by Ni affinity chromatography. First, immunogenicity protective efficacy were evaluated guinea pigs two subcutaneous immunizations with different doses Montanide IMS 206 VG adjuvant. immunized were, respectively, challenged on week 3 after booster immunization strain LJ3 (serovar 13) FX1 4), vaccine-inoculated groups compared nonvaccinated controls. All showed serum antibody titers higher those negative-control groups. Furthermore, cytokine chemokine levels at transcriptional level real-time PCR analysis six cytokines chemokines. Gamma interferon interleukin-5 100 μg elevated 15-fold over rates 80 60% challenge strains FX1, vaccinated recombinant protein. Subsequently, data that single dose (100 μg) protected 80, LJ3, another strain, SZ 14), respectively. results indicate first time protects serovars 13, 4, 14 Taken together, these suggest promising needs to be confirmed