HBV基因瞬时和稳定转染HepG2细胞的TLR4表达

Enhanced expression of TLR4 in HepG2 cells after transient and stable HBV transfection

目的观察HBV基因瞬时和稳定转染HepG2细胞后表达TLR4的变化。方法采用免疫荧光流式细胞术检测TLR4在肝癌细胞株HepG2和HepG2．2．15上表达的平均荧光强度（MFI）及阳性细胞率，将前期试验获得的HBV全基因组，采用脂质体瞬时转染肝癌细胞株HepG2，采用免疫荧光流式细胞术检测TLR4在细胞上表达的MFI及阳性细胞率，台盼蓝计数检测细胞增殖活性，并分析其与细胞表达TLR4的关系。结果HepG2．2．15细胞上TLR4表达的MFI及阳性细胞率均明显高于HepG2（均为P’〈0．01），HepG2细胞于转染HBVDNA各剂量组48h后TLR4表达的MFI和阳性细胞率与无HBVDNA脂质体转染对照组相比均显著升高（均P’〈0．01），并且MFI和阳性细胞率与转染剂量均呈正相关（均P〈0．01），与细胞存活数均呈负相关（均尸〈0．01）。结论瞬时和稳定转染HBV的HepG2细胞，都存在细胞TLR4的上调，这种上调伴随着细胞存活的减少，并可能参与了急慢性乙型肝炎的免疫损伤。

Objective To observe the expression of TLR4 in hepatocellular carcinoma cell line HepG2 after transient and stable HBV genome transfection. Methods Immunofluorescence flow cytometry was used to detect mean fluorescence intensity （MFI） of TLR4 and TLR4 positive cell percentage in hepatocellular carcinoma cell lines HepG2 and HepG2. 2.15. Various doses of HBV DNA plasmid were transfected into HepG2 cells with lipofectamine 2000. Immunofluorescence flow cytometry was used to detect MFI of TLR4 and TLR4 positive cell rate of infected HepG2 cells. Trypan blue staining was used to examine the sum of living cells. Results MFI of TLR4 and TLR4 positive cell rate of HepG2.2.15 cells were significantly higher than those in HepG2 cells （ both P＇ 〈 0. 01 ）. MFI of TLR4 and TLR4 positive cell rate of HepG2 cells transfected by various doses of HBV DNA were significantly higher than those in control group （all P＇ 〈 0.01 ）. MFI of TLR4 and TLR4 positive cell rate of infected HepG2 ceils were positively correlated with the doses of HBV DNA （ both P＇ 〈 0. 01 ） and negatively correlated with the sum of living cells （ both P＇ 〈 0. 01 ）. Conclusions Enhanced expression of TLR4 appeared in HepG2 cells with both transient and stable HBV infection, along with reduction of living cells.