Abstract:

Objective To explore the characteristics of T lymphocyte exhaustion in immune responses from peripheral blood of patients with multidrug-resistant pulmonary tuberculosis (MDR-PTB) by flow cytometry. Methods Fifty-eight patients with pulmonary tuberculosis hospitalized in Shanghai Pulmonary Hospital affilicated to Tongji University were prospectively included from January 2020 to August in 2020, including 20 patients with MDR-PTB, 38 patients with drug susceptible pulmonary tuberculosis (DS-PTB), and 20 healthy donors as control (HD).The elbow vein anticoagulant blood (10ml) of each patient was collected, peripheral blood mononuclear (PBMC) cells were isolated, MTB-specific programmed death-ligand-1 (PD-1), T lymphocyte immunoglobulin and mucin-domain-containing molecules-3 (Tim-3) and lymphocyte activation gene-3 (Lag-3) on CD4⁺ and CD8⁺ T lymphocytes and intracellular cytokines of interleukin-2 (IL-2), interferon gamma (IFN-γ) and tumor necrosis factor-α (TNF-α) were detected by flow cytometry. Results The expression of CD4-PD-1, CD8-PD-1, CD4-Tim-3 and CD8-Tim-3 in MDR-PTB (median (quartile))(respectively were 24.50% (21.58%, 26.00%), 19.95% (16.10%, 21.65%), 3.75% (3.20%, 4.68%) and 12.65% (10.65%, 14.10%)), which were significantly higher than those of HD (respectively were 13.10% (11.80%, 17.80%), 12.55% (9.61%, 18.18%), 0.67% (0.46%, 2.41%) and 3.78% (2.35%, 6.55%)) and DS-PTB (respectively were 14.50% (11.90%, 20.00%), 13.20% (8.61%, 18.23%), 1.12% (0.71%, 3.36%) and 3.59% (2.10%, 7.52%)), the differences were statistically significant (Z=-4.009, -4.159, -3.027, -3.284, -3.565, -3.967, -5.568, -3.261, all P values <0.05). CD4-IL-2 and CD8-IL-2 levels of MDR-TB (1.30% (0.73%, 2.71%), 2.27% (1.03%, 3.11%)) were higher than those of HD (0.67% (0.44%, 1.10%),0.59% (0.39%, 0.91%)), the differences were statistically significant (Z=-2.670, -3.917,all P values <0.05). CD4-IFN-γ of DS-PTB (0.92% (0.59%, 2.02%)) was significantly higher than that of HD group (0.65% (0.38%, 0.82%)), CD8-IFN-γ of MDR-PTB and DS-PTB (1.16% (0.53%, 2.03%) and 1.80% (0.97%, 3.04%)) were significantly higher than that of HD group (0.69% (0.35%, 0.91%)), the differences were statistically significant (Z=-2.337, -1.988,-4.455, all P values <0.05). TNF-α level of DS-PTB (0.83% (0.67%, 1.22%)) was higher than that of HD (0.44% (0.28%, 0.71%)) and MDR-PTB (0.41% (0.28%, 0.82%)), the differences were statistically significant (Z=-3.903, -2.919,all P values <0.05). Conclusion T lymphocyte exhaustion exists in patients with MDR-PTB, T lymphocyte immune effect was inhibited by cells exhaustion.

Key words: Tuberculosis,multidrug-resistant, Immunologic tests, T-lymphocyte subsets, Apoptosis, Evaluation studies