马传贫驴白细胞弱毒疫苗株跨膜蛋白主要免疫决定区基因的克隆与表达

从感染驴白细胞的马传贫驴白细胞弱毒疫苗株前病毒DNA中克隆了编码跨膜蛋白主要免疫决定区(TMIR)的基因，并在大肠杆菌中进行了表达。所表达的融合蛋白有一部分是可溶的，其氨基端带有6个组氨酸的标签，因此可以用固定化金属离子亲和层析法在非变性条件下进行纯化。在间接酶联免疫吸附试验(ELISA)和免疫印迹试验中，重组的TMIR蛋白可与马传贫阳性血清样品发生反应，而与健康马血清无任何反应。这表明该重组蛋白具有良好的抗原性和特异性，可用于马传贫弱毒疫苗株在体内外复制、接种马体内免疫应答及马传贫诊断的研究。

Cloning and expression of the immunodominant region of transmembrane envelope protein from donkey leukocyte-attenuated vaccine strain of equine infectious anemia virus

The immunodominant region of transmembrane envelope protein of the donkey leukocyte-attenuated vaccine strain of equine infectious anemia virus (EIAV) was cloned from its proviral DNA obtained from the vaccine strain infected donkey leukocyte cultures, and expressed in E. coli. The protein was expressed in a partial soluble form and as a fusion protein. There was a 6 histidine tag at its amino acid terminus. It was purified by immobilized metal ion affinity chromatography under native conditions. Recombinant protein of the immunodominant region of transmembrane envelope protein (TMIR) showed reactivity to EIAV positive serum samples and no reactivity to normal horse sera in indirect enzyme-linked immuosorbent assay (ELISA) and immuoblot assay. This demonstrates that the recombinant TMIR protein has very good antigenicity and specificity and may be used for research on the in vitro and in vivo replication and immune responses in the vaccinated horses of donkey leukocyte-attenuated vaccine strain of equine infectious anemia virus and diagnosis for EIAV infection.