Abstract: Objective To explore the changes and the significance of cellular immune function in patients with chronic obstructive pulmonary disease (COPD) complicated by pulmonary tuberculosis (TB).  Methods Fifty in-patients with COPD complicated with pulmonary TB who were detected during July 2012 to June 2013 were enrolled in the study as a study group; the other 50 pulmonary TB patients, 50 COPD patients and 50 healthy people were also enrolled as the control groups. The percentages of NK cells (natural killer cell) and T lymphocyte subsets (such as CD4⁺, CD8⁺ and CD4⁺/CD8⁺) in peripheral blood were measured by flow cytometry-based antibody double-labeling method in all enrolled subjects; the levels of IL-1, sIL-2R, IL-6, IFN-γ and TNF-ɑ were also mea-sured using ELISA method. Single-factor analysis of variance was used for comparison among groups, and t test was used for comparison between two groups. Results The percentage of NK cell in the control group with COPD patients (15.34±8.11)% was higher than that in the control group with TB patients (12.53±7.14)% and the study group (12.37±6.96)% (t=2.08 and 2.20, respectively, both P<0.05). The percentage of CD4⁺ T lymphocyte in the control group with TB patients (39.80±9.42)% was higher than that in the study group (30.09±11.09)% (t=2.80, P<0.01). The level of IL-1 in the study group (30.14±20.84) ng/L was higher than that in the control group with COPD patients (23.54±9.94) ng/L (t=2.00, P<0.05). The level of sIL-2R in the control group with COPD patients (114.70±49.32) pmol/L was lower than that in the study group (168.78±94.92) pmol/L and the control group with TB patients (182.68±74.91) pmol/L (t=4.07 and 5.12, respectively, both P<0.01). The level of IL-6 in the control group with TB patients (75.62±75.97) ng/L was higher than that in the study group (51.46±35.86) ng/L and the control group with COPD patients (48.90±30.04) ng/L (t=2.68 and 2.97, respectively, both P<0.01). The level of IFN-γ in the control group with COPD patients (16.60±9.27) ng/L was lower than that in the study group (28.82±32.40) ng/L and the control group with TB patients (29.90±23.79) ng/L (t=2.89 and 3.15, respectively, both P<0.01).  Conclusion Compared with the patients in all control groups, the patients with pulmonary TB complicated by COPD in the study group have lower expression in NK cells and T lymphocytes, and an abnormal expression of IL-1, sIL-2R, IL-6 and IFN-γ.

Key words: Tuberculosis, pulmonary/complications, Pulmonary disease, chronic obstructive, Cytokines