表达猪肺炎支原体免疫原性基因的重组猪霍乱沙门氏菌对小鼠的免疫原性

【目的】构建表达猪肺炎支原体免疫原性基因的重组猪霍乱沙门氏菌,对重组菌株的生物学特性以及对小鼠的免疫原性进行研究。【方法】分别将猪肺炎支原体的免疫原性基因p36、p46、p65和p97R1-Nrdf克隆到pYA3493,得到重组质粒pYA-36、pYA-46、pYA-65和pYA-97R1-Nrdf。重组质粒和空质粒pYA3493分别电转asd基因缺失株C500ˉ,获得重组菌株C36(pYA-36)、C46(pYA-46)、C65(pYA-65)、C97R1-Nrdf(pYA-97R1-Nrdf)和空质粒菌株CpYA(pYA3493)。研究重组菌株的生物学特性,并以小鼠为动物模型评价重组菌株在口服、肌注两种不同免疫途径下的免疫原性。【结果】成功构建表达猪肺炎支原体免疫原性基因的重组猪霍乱沙门氏菌,重组菌株能表达外源蛋白,生化和生长特性未发生改变,插入的外源基因亦稳定存在。小鼠的免疫原性结果显示:口服C36+C46+C65+C97R1-Nrdf组的猪肺炎支原体抗体极显著高于口服C36+C46+C65组和肌注商品疫苗组(P<0.01),但与肌注C36+C46+C65组无显著性差异(P>0.05);IFN-γ为肌注C36+C46+C65组显著高于肌注商品疫苗组(P<0.05),而与口服C36+C46+C65或C36+C46+C65+C97R1-Nrdf组差异均不显著(P>0.05);IL-4水平为口服C36+C46+C65组>口服C36+C46+C65+C97R1-Nrdf组>肌注商品疫苗组>肌注C36+C46+C65组,但各组之间差异均不显著(P>0.05)。对照组的猪肺炎支原体抗体、IFN-γ以及IL-4均与试验组差异极显著(P<0.01)。【结论】构建的表达猪肺炎支原体免疫原性基因的重组猪霍乱沙门氏菌,采用肌注免疫时具有较好的免疫原性,有望发展为猪肺炎支原体的基因工程疫苗。

Immunogenicity of attenuated Salmonella choleraesuis vaccine strain expressing immunogenic genes of Mycoplasma hyopneumoniae in mice

Objective]The study was carried out to construct and characterize Salmonella choleraesuis vaccine strain expressing immunogenic genes of Mycoplasma hyopneumoniae and to test its immunogenicity in mice.Method] We made p36,p46,p65 and p97R1-Nrdf,the main immunogenic genes of Mycoplasma hyopneumoniae,to insert into the prokaryotic expression plasmid pYA3493.Then these recombinant plasmids and pYA3493 were electroporated into C500 asd-mutant,resulting in the recombinant Salmonella choleraesuis vaccine strains...