肺结核合并糖尿病患者自然杀伤T细胞的变化特点

Changes of natural killer T cells in pulmonary tuberculosis patients complicated by diabetes mellitus

目的 研究肺结核合并糖尿病患者自然杀伤T细胞（NKT细胞）的临床变化特点.方法 2008年1月至2010年6月,选取上海市肺科医院住院的肺结核患者40例为肺结核组,其中男26例,女14例,年龄19～65岁,平均（42±11）岁,平均体重指数（20.6±4.7）kg/m2 肺结核合并糖尿病患者40例为合并糖尿病组,其中男25例,女15例,年龄34～68岁,平均（47±10）岁,平均体重指数（21.3±1.9）kg/m2,采用流式细胞术检测外周血和BALF中表型为T细胞受体Vα24＋Vβ11＋的NKT细胞数量.同期选取门诊体检志愿者37例为对照组,其中男25例,女12例,年龄21～60岁,平均（42±12）岁,平均体重指数（21.9±5.4）kg/m2 门诊糖尿病患者38例为糖尿病组,其中男23例,女15例,年龄36～65岁,平均（44±8）岁,平均体重指数（20.5±3.2）kg/m2,检测外周血NKT细胞的数量[中位数（四分位间距）].计数资料比较采用t检验,组间两两比较采用SNK和LSD检验,采用双变量进行相关性分析.结果 肺结核组外周血NKT细胞[1.1%（0.8%～1.3%）]和合并糖尿病组[0.8%（0.5%～1.0%）]均明显高于对照组[0.4%（0.3%～0.7%）]和糖尿病组[0.3%（0.2%～0.5%）],均差异有统计学意义（q值为3.258～7.074,均P＜0.01） 肺结核组与合并糖尿病组比较,差异有统计学意义（q=2.827,P＜0.01）.肺结核组BALF中NKT细胞数[0.7%（0.3%～1.0%）]明显高于合并糖尿病组[0.3%（0.2%～0.6%）],差异有统计学意义（t=2.394,P＜0.05）.BALF和外周血的NKT细胞数在轻度[0.9%（0.3%～1.3%）和1.0%（0.8%～1.3%）]、中度[0.4%（0.3%～0.9%）和1.0%（0.8%～1.3%）]和重度肺结核患者[0.3%（0.3%～0.5%）和0.7%（0.5%～1.1%）]中的分布差异均有统计学意义（F值分别为4.535和3.763,均P＜0.05）,病情越重NKT细胞数越低.外周血与BALF中NKT细胞数量呈正相关（r=0.709,P＜0.01）.结论 NKT细胞在抗MTB感染中发挥着重要作用.肺结核合并糖尿病患者体内复杂的微环境影响NKT细胞发挥其功能,使其保护性免疫力降低.

Objective To investigate the changes of NKT cells in pulmonary tuberculosis patients （ PTB ） complicated by diabetes mellitus （ DM ）. Methods From January 2008 to June 2010, 40 cases of PTB patients without DM hospitalized in Shanghai Pulmonary Hospital were selected. There were 26 males and 14 females, aged from 19 -65 （ mean, 42 ± 11 ） years, with an average BMI （ 20.6 ±4.7 ） kg/m2.Forty cases of PTB complicated with DM were included as patient controls which consisted of 25 males and 15 females, aged from 34 -68 （ mean, 47 ± 10 ）years, with an average BMI （ 21.3 ± 1.9 ） kg/m2. Thirtyseven healthy controls and 38 cases of non-TB DM in the outpatient department for physical examination were enrolled at the same period. There were 25 male and 12 female healthy controls, aged from 21 -60 （ mean,42 ± 12 ） years, with an average BMI （ 21.9 ±5.4 ） kg/m2. There were 23 males and 15 females in the nonTB DM volunteers, aged from 36 -65 （ mean, 44 ±8 ） years, with an average BMI （ 20. 5 ±3. 2 ） kg/m2.The percentages of NKT cells with the phenotype of TCRVα.24 ＋ Vβ11 ＋ in peripheral blood and bronchial alveolar lavage fluid （ BALF ） were tested by flow cytometry for all the patients. Continuous data were analyzed by t test. Multiple comparisons were performed by SNK and LSD test. Results The percentages of NKT cells in peripheral blood from non-diabetic PTB [ 1.1%（ 0. 8% - 1.3% ） ] and diabetic PTB patients [0. 8% （0. 5% - 1.0% ） ] were all significantly higher as compared with healthy controls [0. 4% （0. 3% -0. 7% ） ] and DM patients without TB [ 0. 3% （ 0. 2% - 0. 5% ） ] （ q = 3. 258 - 7. 074, respectively, all P〈0. 01 ）. The percentages of NKT cells in peripheral blood from non-diabetic PTB patients were also significantly higher as compared with diabetic PTB patients （ q = 2. 827, P 〈 0. 01 ）. The percentages of NKT cells in BALF from non-diabetic PTB patients [0. 7% （0. 3% - 1. 0% ） ] were significantly higher as compared with diabetic PTB patients [ 0. 3% （ 0. 2% - 0. 6% ） ] （ t = 2. 394, P 〈 0. 05 ）. The percentages of NKT cells from BALF in mild, moderate and severe PTB patients were [0. 9% （0. 3% - 1.3% ） ], [0. 4% （0. 3% -0. 9% ） ] and [0. 3% （0. 3% - 0. 5% ） ], respectively, which were significantly different （ F= 4. 535, P 〈0. 05 ）. The percentages of NKT cells from peripheral blood in mild, moderate and severe PTB patients were[1.0%（0.8% -1.3%）], [1.0%（0.8% -1.3%）] and [0.7% （0.5% -1.1%）], respectively, which were also significantly different （F =3. 763, P 〈0. 05）. The percentages of NKT cells from peripheral blood had a positive correlation with those from BALF （ r = 0. 709, P 〈 0. 01 ）. Conclusions NKT cells play an important role in TB infection. The complicated milieus in PTB patients with DM have adverse effects on NKT cells, resulting in their dysfunction.