Cloning of a Chinese Human T-lymphotropic Virus Type I env Gene and the Prokaryotic Expression and Immuno-activity Detection of the Type I+II Chimeric Gene
For development of an antibody detection reagent for human T-lymphotropic virus (HTLV), a full-length envelope (env) gene of HTLV type I (HTLV-I) was cloned from peripheral blood cells of a HTLV-I infected individual in a HTLV endemic region of Fujian, and then a gene fragment of 212 amino acid length from the midpiece of gp46 extending to the N-terminal of gp21 was selected as well as a type specific epitope region of HTLV type II env gene to construct a HTLV I+II chimeric gene. This chimeric fragment was inserted into prokaryotic expression vector pRSET and expressed in E. coli. The yield of the target recombinant protein was about 30%. The final purity is about 95% after electrophoresis elution purification. Detected by Western blotting, this recombinant protein showed strong reaction with four HTLV-I positive sera as well as two HTLV-II positive sera, and had no response to four HTLV negative sera. Thus, this recombinant antigen can be used to develop a diagnostic reagent for HTLV antibody detection.