CD+8CD-28T淋巴细胞在肺结核发病机制中的作用

目的 探讨CD8^＋CD28^-T淋巴细胞在肺结核发病机制中的作用。方法 30例病例为2005年3月至5月遵义医学院附属医院呼吸内科住院及门诊患者，采用流式细胞术检测15例肺结核组患者外周血中CD8^＋CD28^-T淋巴细胞比值、细胞内白细胞介素6（IL-6）水平，以及CD3^＋、CD3^＋CD8^＋、CD8^CD28^＋T淋巴细胞比值，15例慢性支气管炎急性发作期患者作为疾病对照组，15名健康人作为健康对照组。结果 肺结核组和疾病对照组CD3^＋T淋巴细胞分别为（41±16）％和（40±10）％，均显著低于健康对照组[（44±6）％]；肺结核组和疾病对照组CD8^＋CD28^＋T淋巴细胞[（47±16）％和（44±10）％]均显著高于健康对照组[（41±12）％]；肺结核组CD8^＋CD28^＋T淋巴细胞[（15±8）％]显著低于疾病对照组[（20±7）％]，两组均显著低于健康对照组[（32±9）％]；肺结核组CD8^＋CD28^-T淋巴细胞[（27±9）％]显著高于疾病对照组[（22±9）％]，两组均显著高于健康对照组[（10±4）％]；肺结核组CD8^＋CD28^-T淋巴细胞分泌的IL-6水平[（32．4±2．4）％]显著高于疾病对照组和健康对照组[（19．7±3．2）％和（15．2±2．7）％]。结论 肺结核患者CD8^＋CD28^-T淋巴细胞及其分泌的IL-6水平在外周血中上调，CD8^＋CD28^＋T淋巴细胞水平在外周血中下调。CD8^＋CD28^＋和CD8^＋CD28^-T淋巴细胞及其分泌的IL-6可能参与肺结核的发病机制。CD8^＋CD28^＋未和CD8^＋CD28^-T淋巴细胞比值及其分泌的IL-6水平可作为活动性肺结核的辅助诊断指标。

The role of CD+8CD-28 regulatory T lymphocytes in pulmonary tuberculosis

OBJECTIVE: To study the role of CD(8)(+)CD(28)(-) regulatory T cells in tuberculosis. METHODS: The positive rates of CD(3)(+)CD(8)(+)CD(28)(-) T cells, CD(3)(+) T cells, CD(3)(+)CD(8)(+) T cells and CD(8)(+)CD(28)(+) T cells, and the content of IL-6 in CD(8)(+)CD(28)(-) T cells in leukocytes of peripheral blood from 15 patients with pulmonary tuberculosis, 15 patients with chronic bronchitis and 15 healthy controls were detected by flow cytometry. RESULTS: The positive expression rates of CD(3)(+) T cells of tuberculosis group [(41 +/- 16)%] and bronchitis controls [(40 +/- 10)%] were significantly lower than those from healthy controls [(44 +/- 6)%] respectively, but no differences were found between tuberculosis group and bronchitis controls. The CD(3)(+)CD(8)(+) T cells in CD(3)(+) T cells from the tuberculosis group [(47 +/- 16)%] and bronchitis controls [(44 +/- 10)%] were significantly higher than those from the healthy controls [(41 +/- 12)%] respectively, but no differences were found between the tuberculosis group and bronchitis controls. The CD(8)(+)CD(28)(+) T cells in CD(3)(+) T cells from tuberculosis group [(15 +/- 8)%] and bronchitis controls (20 +/- 7%) were significantly lower than those from healthy controls [(32 +/- 9)%] respectively, and those of the tuberculosis group were significantly lower than those from the bronchitis controls. CD(8)(+)CD(28)(-) T cells in CD(3)(+) T cells from tuberculosis group [(27 +/- 9)%] and bronchitis controls [(22 +/- 9)%] were significantly higher than those from healthy controls [(10 +/- 4)%] respectively, and those of the tuberculosis group were significantly higher than those of the bronchitis controls. The level of IL-6 secreted by CD(8)(+)CD(28)(-) T cells from tuberculosis group [(32.4 +/- 2.4)%] was significantly higher than bronchitis controls [(19.7 +/- 3.2)%] and healthy controls [(15.2 +/- 2.7)%] and no differences were found between bronchitis controls and healthy controls. CONCLUSIONS: The number of CD(8)(+)CD(28)(-) T cells and their production of IL-6 in the peripheral blood of tuberculosis patients are significantly increased as compared with the control groups, while the number of CD(8)(+)CD(28)(+) T cells (cytotoxic T cell) is significantly decreased. The results suggest that these cells and IL-6 may be involved in the pathogenesis of pulmonary tuberculosis.