Objective: To explore the expressions and the significance of CD(3)(+)CD(16)(+)CD(56)(+) NKT cells, CD(3)(-)CD(16)(+)CD(56)(+) NK cells and T lymphocyte subsets in peripheral blood of patients with multi-drug resistant (MDR-TB) and extensively drug-resistant (XDR-TB) pulmonary tuberculosis.
Methods: The data of 316 patients with pulmonary tuberculosis hospitalized in Shanghai Pulmonary Hospital from January 2008 to June 2009 were retrospectively analyzed, of whom 119 were newly diagnosed, and 197 were retreated patients. There were 204 males and 112 females, aged from 17 - 88 years, mean (44 ± 16) years. According to the results of drug-resistance, these patients were divided into a MDR group, an XDR group and a sensitive group. There were 146 patients in the MDR group, with 102 males and 44 females, aged from 19 - 84 years, mean (42 ± 16) years. There were 77 patients in the XDR group, with 42 males and 35 females, aged from 18 - 88 years, mean (50 ± 16) years. There were 93 patients in the susceptible group, with 60 males and 33 females, aged from 17 - 83 years, mean (43 ± 19) years. According to the distribution of cavitation in lung fields, these patients were also divided into 1 - 2 lung field affected group (n = 132), 3 - 4 lung field affected group (n = 49) and 5 - 6 lung field affected group (n = 9). The frequencies of NKT cells, NK cells and T cells from whole blood were tested by flow cytometry. Rank test (SAS software) was used for statistic analyses.
Results: The expression rate of NKT cells and NK cells was the highest in the XDR group [11% (6% - 16%) and 7% (4% - 12%)], as compared to the MDR group [8% (5% - 14%) and 6% (4% - 11%)], and the susceptible group [7% (4% - 11%) and 5% (3% - 9%)], the difference being statistically significant (H = 6.478 - 8.369, P < 0.05). The expression rate of the NKT (14 ± 9)% and NK cells (11 ± 7)% in males of the XDR group was significantly higher than that in females [NKT (9 ± 5)% and NK cell (6 ± 4)%], while CD(4) (38 ± 10)% and CD(4)/CD(8) (1.9 ± 1.3) were significantly lower than those of the females [CD(4) (44 ± 10)% and CD(4)/CD(8)(2.2 ± 0.7)], the difference being statistically significant (z = -2.91 - -2.79, P < 0.05, P < 0.01). The expression rate of CD(4) (42 ± 9)% was the highest, but CD(8) (22 ± 8)% was the lowest in the 1 - 2 lung field group. While in the 5 - 6 lung field group, the expression rate of CD(4) (36 ± 11)% was the lowest, CD(8) (28 ± 12)% was the highest, and CD(4)/CD(8) (1.5 ± 0.8) was the lowest, the difference being statistically significant (H = 8.404 - 16.175, P < 0.01).
Conclusions: With the increasing level of drug resistance, the expression rate of NKT cells and NK cells increased, while the expression of T cell subsets did not change. The value of CD(4) and CD(4)/CD(8) in peripheral blood decreased, but CD(8) increased as the extent of cavitation increased in these patients. The impairment of cellular immune function in XDR-TB was more prominent in male patients.