The role of the hepatitis B virus (HBV) endogenous pre-core protein in liver fibrosis is controversial. Whether the expression of the pre-core induces the activation of human stellate cells (HSCs) has not yet been reported. Plasmids expressing HBx, or pre-core protein were transfected into LX-2 cells. Subsequently, total RNA extracted and reverse transcription-quantitative polymerase chain reaction was performed to measure the fold change of collagen type I, α1 chain, α-smooth muscle actin and TIMP metalloproteinase inhibitor-1. Moreover, transforming growth factor (TGF)-β in the supernatant of HSCs was evaluated by ELISA assay. In addition, a MTT assay was performed to test the cytotoxicity of the endogenous expression in LX-2 cells. None of the plasmids exhibited cytotoxic nor significant proliferative effects on LX-2 cells by MTT assessment. The gene expression analysis of fibrotic genes in LX-2 cells demonstrated that the pre-core protein presented no significant (P>0.05) fibrotic impact when compared to the empty control plasmid and HBx. The data from the TGF-β ELISA was consistent with the mRNA expression as detected with the control plasmid (P>0.05). The endogenous expression of the HBV pre-core exhibited no fibrotic impression in HSCs when compared to HBx.
Keywords: fibrosis; hepatic stellate cell; hepatitis B virus; pre-core protein.