禽大肠埃希氏菌O_(78)和巴氏杆菌(5∶A)外膜蛋白的免疫研究

Immunogenicity of outer membrane proteins of avian Escherichia coli and Pasteurella multocida

用超声裂解、Sarkosyl处理和超速离心法提取禽大肠埃希氏菌O78强毒株 (简称O78)、O78耐氯霉素弱毒株 (简称O78r)、禽多杀性巴氏杆菌 5∶A强毒株C4 8 1(简称C4 8 1)、O78r 与C4 8 1的融合双价弱毒株F4 (简称F4 )菌体外膜蛋白 (OMP)。经SDS PAGE结果显示 ,O78、O78r、C4 8 1与F4 均有 1条分子质量为 31.0～ 4 3.0ku ,分子质量相近的OMP条带 ;O78与C4 8 1还有 1条分子质量小于31.0ku且相近的OMP条带。用OMP制备的油乳剂疫苗分别免疫小白鼠 15d和岭南黄鸡后 2 2d ,以O78、C4 8 1强毒菌攻击 ,结果表明O78、C4 8 1的OMP不但对同源菌具有免疫作用 ,且具有交叉免疫保护作用 ;用各自的OMP作包被抗原 ,建立的ELISA方法也能交叉检测到 3组OMP免疫鸡产生的抗 2种菌OMP的IgG抗体。

The outer membrane proteins(OMP) of virulent avian Escherichia coli O_(78) strain(O_(78)), virulent Pasteurella multocida C_(48-1)(5∶A) strain(C_(48-1)), attenuated avian Escherichia coli O_(78)~r strain(O_(78)~r ) and attenuated fusion strain of O_(78)~r-C_(48-1)(F_(4 )), were extracted respectively by means of sonication, sarkosyl treatment and ultracentrifugation. The SDS-PAGE of the OMP show that one OMP band (about) 31 ku or 41 ku in molecular weight existed in all of the four strains. Another one OMP band with a molecular weight of 34 ku was found in O_(78), O_(78)~r and C_(48-1). Young mice and chickens were challenged by virulent O_(78) and C_(48-1) on day 15 and day 22 respectively after being vaccinated with the emulsified OMP of O_(78) and C_(48-1) or F_(4). The results showed that all the OMP of the three bacteria have immunogenicity and can induce cross-protective immunity. The antibodyIgG of the chicken sera against all the three OMP can be detected with the OMP of O_(78) and C_(48-1)as coated-antigens by ELISA.