【摘要】 猪瘟是一种由猪瘟病毒(Classical swine fever virus,CSFV)引起的高度接触传染性和致死性疾病.疫苗预防接种是控制猪瘟病毒传播的重要措施,目前我国使用的弱毒疫苗均为1.1亚型猪瘟病毒兔化弱毒株.随着病毒的不断变异,2.1亚型猪瘟病毒已经逐渐成为我国的主要流行毒株.本研究利用马克斯克鲁维酵母研究了2.1b型CSFV E2蛋白及其截短体mE2(690-916aa)在马克斯克鲁维酵母中的重组表达,发现去除E2蛋白跨膜区域可以显著提高E2蛋白表达水平,mE2的表达量在5L发酵罐中达1.25～2.5g/L.经分子筛纯化,mE2蛋白纯度达90%.纯化的mE2作为抗原蛋白,注射免疫小鼠28d后,可诱导小鼠产生抗CSFV的IgG特异性抗体,表明马克斯克鲁维酵母重组表达的mE2蛋白具有较好的免疫原性.更多还原

【Abstract】 Classical swine fever,caused by classical swine fever virus(CSFV),is a highly contagious disease and leads to severe fatality of swine.Infection and spread of CSFV can be prevented by prophylactic vaccinations.CSFV vaccines used in China are mainly against CSFV 1.1subtype.However,CSFV 2.1bsubtype has become the predominant epidemic strain in China,due to the rapid evolution of CSFV.In this study,recombinant expression of E2 protein and its truncated form from CSFV 2.1bstrain were obtained in a novel host,Kluyveromyces marxianus.We found that the amount of expression of E2 protein could be significantly inhibited by transmembrane region of E2 protein.High-level expression of mE2,a truncated form of major antigenic protein E2(aa 690—916),was achieved.The protein level of mE2 in the cell lysate reached 1.25—2.5g/L after growing in a5 Lfermentor.After purification by gel-filtration,the purity of the mE2 protein was more than 90%.Purified mE2 was used as antigen protein and injected into mice.Antibodies against E2 could be detected in the serum of mice 28 days after injection.The results suggest purified mE2 displays good immunogenicity and can induce humoral immunity.更多还原