Abstract: AIM: To explore the immunotheraptical drugs for multi-drug resistant pulmonary tuberculosis (MDR-TB). METHODS: 79 patients with MDR-TB were randomly assigned to two groups.46 cases in M. vaccae group were treated with “3AkPaThLevl/15Pa-ThLevL” and M. vaccae, and 33 cases in control group were treated only with“3AkPaThLevl/15PaThLevL”. The clinical effect and T-lymphocyte subsets in patients were observed after being treated for 1, 2 and 3 months, re-spectively. RESULTS: The sputum negative rates (41.3%, 63.0%, and 80.4%) and the X-ray resolu-tion rates (30.4%, 50.0%, and 67.4%) of the M. vaccae group were superior to those (12.1%, 27.3%, and 39.4%, P<0.001) and those (6.1%, 21.2%, and 27.3%, P<0.05) of the control group after being treated for 1, 2 and 3 months.The percent of ${CD_{3}}^{+}$,${CD_{4}}^{+}$and the ratio of ${CD_{4}}^{+}$ ${CD_{8}}^{+}$ of the M. vaccae group were significantly higher than that of the control group (P<0.001), while the percent of ${CD_{8}}^{+}$ of the M. vaccae groupwas significantly lower than that of the control group (P<0.05). CONCLUSION: The M. vaccae can en-hance the cellular immune function of the patients with MDR-TB.

Key words: pulmonary tuberculosis, multi-drug re-sistant, immunotherapy, cellular immune function, T-lym-phocyte subsets, M. vaccae