尼古丁对体外培养人外周血单个核细胞分泌TNF的影响

Effect of nicotine on the secretion of TNF of human peripheral blood mononuclear cells in vitro

目的 :观察尼古丁对体外培养人外周血单个核细胞分泌肿瘤坏死因子 (TNF)的影响 ,探讨吸烟使血浆TNF水平升高的可能机制。方法 :分离 2 1名不吸烟与 19名吸烟健康志愿者的外周血单个核细胞 (PBMC)。每名志愿者的PBMC分成A ,B ,C三组 ,A组培养基中不加尼古丁 ,B和C组培养基中分别加入 5 0ng·ml- 1 和 5 0 0ng·ml- 1 浓度的尼古丁 ,体外培养 72h后检测上清液TNF水平 ,观察细胞增殖情况。结果 :吸烟A组TNF水平显著高于不吸烟A组 (P <0 .0 5 ) ,吸烟B组TNF水平显著高于不吸烟B组 (P <0 .0 5 ) ;不吸烟C组TNF水平显著高于不吸烟B组 (P <0 .0 5 ) ,且两组均显著高于不吸烟A组 (P <0 .0 1,P <0 .0 5 ) ;吸烟B组TNF水平显著高于吸烟A组 (P <0 .0 5 ) ;而吸烟C组TNF水平则显著低于吸烟A组和不吸烟C组 (P <0 .0 5 ,P <0 .0 5 ) ,且PBMC增殖也受到抑制 ,其增殖倍数显著低于吸烟A组和不吸烟C组 (P <0 .0 5 ,P <0 .0 5 ) ,TNF水平与细胞增殖倍数呈正相关 (r =0 .93,P <0 .0 5 ) ,直线回归方程式为 ^Y =2 .913X - 2 .95 5。结论 :尼古丁可以促进体外培养的人外周血单个核细胞分泌TNF ,且作用大小随剂量增大而增大 ,但高浓度尼古丁反而抑制TNF分泌 ,这可能是吸烟升高血浆TNF水平的机制之一。

Objective To observe the effect of nicotine on the secretion of TNF of human peripheral blood mononuclear cells (PBMC) in vitro, and explore the possible mechanism of the high level of TNF caused by smoking. Methods Twenty one non smokers and 19 smokers were studied. The PBMCs isolated from each volunteer's blood sample were distributed to three groups, and cultured for 72 hours in supplemented RMPI 1640 alone or in supplemented RPMI 1640 containing 50 ng·ml -1 nicotine or 500 ng·ml -1 nicotine respectively. The level of TNF in supernate was quantified with the immuno radioassay, and PBMC proliferation was observed. Results The level of TNF spontaneously secreted by PBMCs in smokers was significantly higher than that in non smokers (P<0.05). When the concentrations of nicotine were 50 ng·ml -1 and 500 ng·ml -1 , the level of TNF increased significantly in non smokers (P<0.05,P<0.01). In smokers, the level of TNF significantly increased when the concentration of nicotine was 50 ng·ml -1 ; however, the level of TNF significantly decreased (P<0.05), and the proliferation of PBMCs was inhibited when the concentration of nicotine was 500 ng·ml -1 (P<0.05, P<0.05). The level of TNF was positively correlated to the multiple of PBMC proliferation (r=0.93, P<0.05). The linear regression equation was =2.913X-2.955. Conclusion Nicotine can induce PBMCs to secrete more TNF, and the magnitude of the effect is strongly related to the dosage of nicotine, but a great dose of nicotine will inhibit the production of TNF.