调控中性白细胞凋亡有关因素的体外实验

目的:用体外实验观察多种因素(包括亚砷酸钠、TNF-α、IL-6及烧伤血清、创伤血清)对中性白细胞(PMN)凋亡的影响,为探索一种新的保护组织免遭继发性损害的方法提供依据。方法:分离纯化人外周血PMN,与亚砷酸钠(Ars)、TNF-α、IL-6及烧伤血清、创伤血清作用后,测定凋亡比例、CD 11 b表达、呼吸爆发、胞质Ca²⁺浓度的改变。结果:Ars浓度与PMN凋亡呈剂量依赖关系,激活的PMN却对Ars失敏;IL-6使PMN凋亡延迟(与24 h对照相比,P＜0.05),抑制CD 11 b表达(与24 h对照相比,P＜0.01);烧伤血清和创伤血清的作用较IL-6更为明显。结论:发现PMN激活后对Ars失敏,其机理不清;CD 11 b表达升高与PMN凋亡增多呈正相关;IL-6、烧伤血清、创伤血清能延迟PMN凋亡,部分恢复PMN的功能。

Factors involved in regulation of polymorphonuclear neutrophilsapoptosis in vitro

AIM:This study aimed at elucidated the possibility that prevent tissue from secondary injury by regulating polymorphonuclear neutrophil (PMN) apoptosisin vitro. METHODS:Neutrophils, isolated from peripheral blood, were incubated with sodium arsenite (Ars), tumor necrosis factor (TNF-α), interleukin-6 (IL-6), burned serum and traumatic serum, respectively. Apoptosis rate, expression of CD11b, respiratory burst and concentration of Ca²⁺ were then measured. RESULTS:The elevation of PMN apoptosis rate was Ars concentration dependent, but activated PMN became insensitive to Ars. IL-6 delayed PMN apoptosis (compared with control at 24 h,P＜0.05), inhibited CD11b expression. Burned and traumatic serum had more significant effects on PMN compared with IL-6. CONCLUSION:PMN was observed for the first time to resist spontaneous apoptosis when activated by LPS/TNF, and became insensitive to apoptosis-inducing substance Ars. IL-6, burned serum and traumatic serum could delay PMN apoptosis and recover PMN functions partly.