抗O型口蹄疫病毒DNA疫苗的建立

Construction of DNA vaccine against foot-and-mouth disease virus

目的 :研制抗“O”型FMDV的DNA疫苗。方法 :以“O”型口蹄疫病毒 (FMDV)Vp1免疫活性肽基因串联片段取代猪IgGH链可变区的CDR3区 ,并与真核表达载体pCDM8相连构建表达载体pCDM FH。用表达载体pCDM FHDNA对豚鼠及猪进行肌肉注射 ,检测该疫苗的免疫效果。结果 :该DNA疫苗可诱导出抗FMDV专一性的中和抗体及效应性T细胞。攻毒试验表明 ,DNA疫苗pCDM FH可使被免疫豚鼠及猪发病推迟 ,症状减轻。结论 :该DNA疫苗可激发明显的免疫应答及保护效果。

Objective:To develop DNA vaccine against FMDV O type.Methods:The CDR3 region of swine IgG H chain was replaced by nucleotide acid fragment encoded peptides containing the two copies of amino acid residues 141～160 and one copy of amino acid residues 200～213 of Vp1 of FMDV type O to form fusion gene. The fusion gene was cloned into eukyotic expression vector pCDM8 to construct recombinant plasmid pCDM FH. Guinea pigs and swine were intramuscularly immunized with the expression vector pCDM FH.Results:pCDM FH immunized guinea pigs developed FMDV specific T cells and FMDV neutralizing antibodies.The time that guinea pigs got disease were postponed until two days later and the lesion degree of guinea pigs and swines alleviated after guinea pigs and swines vaccinated with the pCDM FH vector were challenged with FMDV.Conclusion:The DNA vaccine pCDM FH is able to induce significant immune responses and partial protection against FMDV O type in guinea pigs and swines.