牙龈卟啉单胞菌脂多糖诱导T淋巴细胞活化、凋亡的体外研究

The study of T lymphocytes apoptosis induced by Porphyromonas gingivalis lipopolysaccharide(LPS) in vitro

目的检测牙龈卟啉单胞菌脂多糖（LPS）对人外周血中T淋巴细胞活化及凋亡的作用。方法选取10名全身及牙周组织健康受试者，分离外周血中T淋巴细胞，在有／无 LPS情况下培养0-96h，用荧光探针（AnnexinV-FITC、PI、CD69）进行标记，并进行流式细胞仪检测。结果T淋巴细胞＋LPS组AnnexinV＋／PI-细胞百分数在48h、72h、96h分别为16．36±2．22，27．16±2．81，47．17±4．70。T淋巴细胞组AnnexinV＋／PI-细胞百分数在48h、72h、96h分别为7．55±2．76，6．32±1．48，12．03±3．24，两组间存在明显差异（P〈0．01）。CD69＋T淋巴细胞＋LPS组和CD69＋T淋巴细胞组AnnexinV＋／PI-细胞百分数除24h外的4个时间点上都无明显差异（P〉O．05）。CD69＋淋巴细胞＋LPS组Annexinv＋，PI-细胞百分数在各个时间点上都明显高于T淋巴细胞＋LPS组（P〈0．01）。结论LPs能够诱导人外周血中T淋巴细胞活化，并且能够通过活化促进其凋亡。

Objective To investigate the induction effects of Porphyromonas gingivalis lipopolysaccharide （LPS） on activation and apoptosis of the human peripheral blood T lymphocytes. Methods Ten systemically and periodontally healthy subjects participated in this study. Venous blood was drawn and peripheral blood mononuclear cells （PBMC） was isolated. Stimulating the T lymphoeytes with LPS and the cells were labled by the special monoclonal antibodies and analyzed by flow cytometry. Results The percentages of Annexin V＋/PI-cells in the group of T lymphocytes with LPS were 16.36±2.22, 27.16±2.81, 47.17±4.70 at 48h, 72h, 96h respectively; and those in the group of T lymphocytes without LPS were7.55±2.76, 6.32±1.48, 12.03±3.24 respectively. The differences in percentages of Annexin V＋/PI-eells between the two groups were significant （P〈0.01）. The percentages of Annexin V＋/PI-cells in the group of CD69＋T lymphocytes with LPS and the group without LPS were not significantly different （P〉0.05） at four time points except at 24h. The percentages of Annexin V ＋/PI-eeUs in the group of T lymphocytes with LPS were greater than those in the group of CD69＋T lymphocytes with LPS （P〈0.01）. Conclusion LPS could induce the activation of T lymphocytes and promote the apoptosis through activation.