Alemán Mercedes, García Ana, Saab María A, De La Barrera Silvia S, Finiasz Marta, Abbate Eduardo, Sasiain María C
Departamento de Inmunología, Instituto de Investigaciones Hematológicas, Academia Nacional de Medicina, Buenos Aires, Argentina.
Am J Respir Cell Mol Biol. 2002 Nov;27(5):583-92. doi: 10.1165/rcmb.2002-0038OC.
The activation of circulating polymorphonuclear neutrophils (PMN) from patients with active tuberculosis (TB-PMN) may be associated with induction of apoptosis. Spontaneous or Mycobacterium tuberculosis (MTB)-induced apoptosis of PMN were evaluated by microscopy, DNA content, and their binding to Annexin V at 0, 3, and 18 h. In addition, the expression of CD11b and of CD16 were evaluated as parameters of activation and apoptosis, respectively. Recently isolated TB-PMN showed a higher CD11b expression than normal PMN (N-PMN), but there were no features of apoptosis, even though an enhancement of Fas expression was observed. Spontaneous apoptosis was accelerated in TB-PMN at 3 h, but no differences were observed in TB- and N-PMN at 18 h of culture. When stimulated with MTB, both TB- and N-PMN steadily increased CD11b expression along the culture period. MTB induced apoptosis of N-PMN at 3 h with loss of CD16 expression. By contrast, MTB delayed the apoptotic rate of TB-PMN, preserving the CD16 receptor at 3 h, whereas it accelerated apoptosis at 18 h, increasing at the same time the expression of CD11b. Taken together, these data suggest that the acceleration of apoptosis observed in TB-PMN could be associated with the MTB-induced activation.
活动性肺结核患者循环中的多形核中性粒细胞（TB-PMN）的激活可能与细胞凋亡的诱导有关。通过显微镜检查、DNA含量以及在0、3和18小时时它们与膜联蛋白V的结合情况，评估PMN的自发凋亡或结核分枝杆菌（MTB）诱导的凋亡。此外，分别评估CD11b和CD16的表达作为激活和凋亡的参数。最近分离的TB-PMN显示出比正常PMN（N-PMN）更高的CD11b表达，但即使观察到Fas表达增强，也没有凋亡特征。TB-PMN在3小时时自发凋亡加速，但在培养18小时时，TB-PMN和N-PMN之间没有差异。当用MTB刺激时，TB-PMN和N-PMN在整个培养期间CD11b表达均稳步增加。MTB在3小时时诱导N-PMN凋亡，同时CD16表达丧失。相比之下，MTB延迟了TB-PMN的凋亡率，在3小时时保留了CD16受体，而在18小时时加速了凋亡，同时增加了CD11b的表达。综上所述，这些数据表明，在TB-PMN中观察到的凋亡加速可能与MTB诱导的激活有关。
