脂多糖诱导原代培养肝实质细胞与库普弗细胞表达和释放高迁移率族蛋白B1

目的观察LPS诱导HMGB1在肝实质细胞（HC）与库普弗细胞（KC）的表达和细胞外释放。方法培养瓶中分别培养原代HE和KC,24h后收获对照组和500μg/L LPS诱导组两种细胞,反复冻融,用半定量RT-PCR和Western blot法检测HMGB1 mRNA水平和HMGB1表达水平;接种原代HC和KC于24孔板中,继续培养6、12、24h和48h,Western blot法检测各时间点对照组和LPS诱导组培养液中HMGB1含量。结果LPS诱导24h后,与相应对照组比较,HC和KC中HMGB1 mRNA表达水平明显增强（t值分别为31.32和45.90,P值均〈0.05）,HMGB1表达水平也明显增强（t值分别为46.19和38.44,P值均〈0.05）;在6、12、24h和48h,对照组两种细胞及诱导组HC培养上清液中仅检测到少量HMGB1,延长培养时间,培养上清液中HMGB1含量无明显变化（F=1.61,P〉0.05）;与对照组比较,诱导组KC培养液中的HMGB1含量在6h无显著增加（t=1.48,P〉0.05）,但随培养时间延长,其含量明显增高（F=42.74,P〈0.05）,且在12、24h和48h均明显高于对照组（t值分别为21.95,32.39和44.16,P值均〈0.05）。结论LPS可诱导HC和KC中HMGB1表达增强,HC不主动释放HMGB1,而KC能主动释放HMGB1到细胞外。

Expression of HMGB-1 and its extracellular release of cultured primary hepatic parenchymal cells and Kupffer cells induced by LPS

OBJECTIVE: To investigate HMGB-1 expression and its extracellular release of cultured primary hepatic parenchymal cells (HC) and Kupffer cells (KC) that were induced by lipopolysaccharides (LPS). METHODS: Primary hepatic parenchymal cells and Kupffer cells were cultured in flasks, and some cells were treated with 500 microg/L LPS for 24 hours (induced group) and some were not treated with LPS and served as controls. All of the cells were repeatedly frozen-thawed, and the expression levels of HMGB1-mRNA and HMGB1 proteins were detected by semi-quantitative RT-PCR and Western blot respectively. Then HC and KC were subcultured in 24-well culture plates for 6 h, 12 h, 24 h and 48 h, and the HMGB1 protein in culture fluids was detected by Western blot at each time point. RESULTS: Compared with the cells in the control group, the expression levels of HMGB1-mRNA in the induced group were significantly increased in both HC and KC at 24 h (t=31.32 and 45.90, P<0.05) and the protein levels of HMGB1 showed the same results (t=46.19 and 38.44, P<0.05). There was a small quantity of HMGB1 protein in the culture fluids of two control groups and the induced group of HC. However the HMGB1 protein in the induced group of KC were obviously increased with prolonged culture time (F=42.74, P<0.05). Compared with the control group, the level of HMGB1 protein in the induced group of KC was not increased at 6 h (t=9.57, P>0.05) but was significantly increased at 12 h, 24 h and 48 h (t=21.95, 32.39, 44.16, respectively P<0.05). CONCLUSION: LPS could increase HMGB1 expression of HC and KC and HMGB1 release from KC, but not from HC. The results suggest that KC play an important role in triggering inflammation and liver injury.