Abstract: Objective To observe the DTH reaction induced by recombinant antigen of M.tuberculosis MPT64(M)、Ag85A(A)、ESAT6(E) and the mixture of two of them.Methods Normal skin test:The guinea-pig were sensitived by all body of dead H₃₇R_v.We used water as negative control,5U PPD as positive control,0.8μgE、0.8μgM、0.8μgA、0.4μgA+0.4μgM、0.4μgA+0.4μgE、0.4μgE+0.4μgM were injected on guinea-pig’s back respectively.The Results were observed 24、48、72h after injection.Alternative skin test:water、5U PPD、0.8μgE、0.8μgM、0.8μgA、0.4μgA+ 0.4μgM、0.4μgA+ 0.4μgE、0.4μgE+ 0.4μgM were injectecd on the back of the same guinea-pig.The Results were observed 24、48、72h respectively after injection.Results Normal skin test showed:the DTH reaction of guinea induced by 0.8μgM、A、M+E、E+A mixture respectively was no real difference with the DTH reaction induced by PPD (P＞0.05).But the DTH reaction induced by 0.8μgE and M+A mixture respectively was stronger than the Results induced by PPD (P＜0.05).24h after injection was the best observing time of the test.The Results of alternative skin test were coincidence with normal skin test.Conclusion The DTH reaction induced by ESAT6 and A+M compounds was stronger than the DTH Results induced by PPD.

Key words: M.tuberculosis, Recombinant antigen, DTH