钛离子对T淋巴细胞体外增殖及活化的影响

Effects of titanium ions on the proliferation and activation of T lymphocytes in vitro

背景:已有研究证实,钛离子可以刺激T淋巴细胞分泌骨改建相关因子,然而尚无文献报道钛离子对T淋巴细胞早期活化、中期活化及细胞周期的作用。目的:观察钛离子对T淋巴细胞体外增殖和活化的影响。方法:(1)细胞增殖与周期实验:取对数生长期Jurkat E6-1 T淋巴细胞,分组培养,对照组、低浓度组、中浓度组、高浓度组分别加入含0,25,50,100μmol/L钛离子的培养基培养,24 h后,检测细胞相对增殖率与细胞周期;(2)细胞活化实验:先将Jurkat E6-1 T淋巴细胞分为两大组,一组预先进行植物血凝素刺激,另一组不进行植物血凝素刺激,两组再分别分为对照组、低浓度组、中浓度组、高浓度组4个亚组,24 h后,检测细胞早期活化抗原CD69和中期活化抗原CD25的表达。结果与结论:(1)细胞增殖:钛离子呈浓度依赖性促进T淋巴细胞的增殖(P<0.05);(2)细胞周期:与对照组比较,低浓度组、中浓度组、高浓度组G_0/G_1期细胞比例降低(P<0.05),S期、G_2/M期细胞比例明显升高(P<0.05);高浓度组G_0/G_1期细胞比例低于低、中浓度组(P<0.05),G_2/M期细胞比例高于低、中浓度组(P<0.05);(3)细胞活化实验:植物血凝素刺激预先刺激下,高浓度组CD69表达高于对照组、低浓度组、中浓度组(P<0.05),4组间CD25表达比较差异无显著性意义;无植物血凝素刺激预先刺激下,钛离子呈浓度依赖性促进CD69的表达(P<0.05),各组均无CD25表达;(4)结果表明:钛离子能促进T淋巴细胞体外增殖及早期活化,同时能诱导T淋巴细胞进入S期、G_2/M期。

BACKGROUND：Titanium ions have been proved to stimulate the secretion of bone remodeling-related factors from T lymphocytes;however, the effects of titanium ions on the early activation, intermediate activation, and cel cycle of T lymphocytes remain unclear. OBJECTIVE：To investigate the effects of titanium ions on the proliferation and activation of T lymphocytes in vitro. METHODS：Cel proliferation and cycle test：Jurkat E6-1 T lymphocytes in logarithmic phase were col ected and cultured in the medium containing 0 （control）, 25 （low concentration）, 50 （middle concentration）, and 100μmol/L （high concentration） titanium ions for 24 hours to detect the cel relative proliferation rate and cel cycle. Cel activation trial：Jurkat E6-1 T lymphocytes were divided into two groups that were subdivided into four groups containing 0, 25, 50, and 100μmol/L titanium ions, respectively with or without phytohemagglutinin （PHA） pre-stimulation. The expressions of CD69 and CD25 were measured after cultured for 24 hours. RESULTS AND CONCLUSION：Titanium ions enhanced T lymphocytes proliferation in a concentration-dependent manner （P〈0.05）. Compared with the control group, the percentages of G0/G1 phase decreased and the proportions of cel s in S and G2/M phase increased significantly in the low, middle and high concentration groups （P〈0.05）. The proportion of G0/G1-phase cel s in the high concentration group was less and the proportion of G2/M phase cel s was higher than those in the middle and low concentration groups （P〈0.05）. With PHA pre-stimulation, the expression of CD69 in the high concentration group was higher than that in the middle and low concentration groups （P〈0.05）;whereas the difference of CD25 expression was not significant among four subgroups. Titanium ions promoted the expression of CD69 in a concentration-dependent manner （P〈0.05）, but there was no CD25 expression in each subgroup without PHA pre-stimulation. To conclude, titanium ions can significantly promote T lymphocyte proliferation and early activation in vitro, and moreover, induce S and G2/M phase arrest in T lymphocytes.