Changes Of The Peripheral Blood CD4~+ CD25~+ Foxp3+~T Cells In Patients With Multidrug-resistant Tuberculosis

Objective: MDR-TB, defined as MTB caused by organisms that are resistant to isoniazid and rifampicin, continues to threaten the progress made in controlling the disease now. The development and outcome of TB depends not only on the number and virulence of MTB, but also on the immune status. As MTB is an intracellular bacterium, the body's anti-TB immunity depends on the specific cellular immunity. Macrophages are the place of MTB parasitism, and the important immune cells of natural immunity against MTB infection. CD4~+T cells are the main cells mediating cellular immune response. It can be classified Th1, Th2, Treg, Th17 subsets, and so on. Various cytokines play an important role in cellular immune. This study is to investigate the role of CD4~+CD25~+Foxp3~+T cell and TGF-β1 in patients with MDR-TB.Methods: We recruited 31 multidrug-resistant TB patients, 33 drug-susceptible TB patients and 30 healthy controls in accordance with the requirements of cases selected and guidelines for the diagnosis and therapy of pulmonary TB. Under the fasting, sterile conditions, 5 ml of venous blood of all patients and HCs was collected in the morning. 1 ml blood added to heparin sodium tubes for analysis with flow cytometry and the others added to non-anticoagulation tubes then were placed at room temperature for 30min. the supernatant was harvested and placed at -70 degree for ELISA analysis. The partition of CD4~+CD25~+Foxp3~+T cells in the peripheral blood were determined by flow cytometry. TGF-β1 levels in the peripheral blood were detected by ELISA.Results: CD4~+CD25~+Foxp3~+T cell and TGF-β1 comprised in the peripheral blood of patients with MDR-TB were (3.14±0.59)% of peripheral CD4~+ T cell and (29.24±4.25)ng/ml, respectively. It was significantly higher than that of HCs and patients with S-TB(p<0.05). TGF-β1 level and CD4~+CD25~+Foxp3~+T cells / CD4~+ cells ratio in the peripheral blood of patients with MDR-TB was significantly correlated (r = 0.67, p <0.01).Conclusion: CD4~+CD25~+Foxp3~+T cells and TGF-β1 comprised in the peripheral blood of patients with S-TB was significantly higher than the HC group, suggesting that the cellular immune function of patients with S-TB decreased.CD4~+CD25~+Foxp3~+T cells and TGF-β1 comprised in the peripheral blood of patients with MDR-TB were significantly higher than those of the S-TB group, suggesting that degree of immune dysfunction of patients with MDR-TB was associated with CD4~+CD25~+Foxp3~+T cells and TGF-β1 comprised in the peripheral blood. Function of patients with MDR-TB even heavier damage. TGF-β1 level and CD4~+CD25~+Foxp3~+T cells/CD4~+ cells ratio in the peripheral blood of patients with MDR-TB was significantly correlated, suggesting that the inhibition to cellular immune response co-promoted the occurrence and development of MDR-TB.