Abstract: Objective To construct a recombinant plasmid of CFP10-ESAT-6-CFP21(CE21)fusion protein of Mycobacterium tuberculosis and evaluate the diagnosis value of CE21 fusion protein to tuberculosis based on IFN-γ detecting.Method The genes encoding CFP21 and CFP10-ESAT-6(CE)protein were amplified by PCR,cloned into vector pMD18-T respectively and then cloned into expression vector pET21a(+)twice.Recombinant pET21a-CFP10-ESAT-6-CFP21 plasmid was obtained and transformed into E.coli BL21(DE3).After express...