Preparation and antigenicity assay of recombinant proteins of Mycobacterium tuberculosis

    SU Mingª²Quan1, YUE Qiaoª²Hong1, ZHOU Ping2£¬DUAN Yan3, YANG Liu3, YANG Junª²Lan1, LIU Jiaª²Yun1, HAO Xiaoª²Ke1

    1Department of Clinical Laboratory, Xijing Hospital, Fourth Military Medical University, Xi¬ðan 710033, China, 2Department of Clinical Laboratory, First Hospital, Xi¬ðan Jiaotong University, Xi¬ðan 710061, China, 3Xi¬ðan Tuberculosis and Thoracic Tumor Hospital, Xi¬ðan 710058, China

    ¡¾Abstract¡¿ AIM: To clone and express the Mr 16¡Á103 and Mr 38¡Á103 proteins of Mycobacterium tuberculosis in E. coli£¬ and to characterize its antigenicity and specificity. METHODS: The Mr 16¡Á103 and Mr 38¡Á103 antigen genes were amplified from Mycobacterium tuberculosis genome DNA by polymerase chain reactions and cloned into pGEXª²4Tª²2 expression vector after sequencing. BL21 strain of E.coli was transformed with the recombinant vectors and induced to express recombinant proteins. The proteins were purified by affinity column chromatography. The antigenicity and specificity of purified proteins were estimated by enzymeª²linked immunoabsorbant assay. RESULTS: The BL21 strains of E. coli with recombinant vectors showed 42% and 18% of Mr 16¡Á103 (688 mg/L) and Mr 38¡Á103 (217 mg/L) gene expressions after induction. The sensitivity of Mr 16¡Á103 and Mr 38¡Á103 proteins were 67.0% and 79.8%, specificity were 100% and 99% ......