Fig. 4

HBV activates HSCs through the RUNX2/ITGBL1 axis. Huh7 cells. (2 × 10⁵ cells/well) were cultured for 12 h and transfected with 2 µg of the 1.2 HBV expression plasmid. Vitamin D₃ (50 ng/mL) was also added. To collect conditioned medium for LX-2 culture, Huh7 and HepG2 cells were cultured in FBS-free Williams E medium for 48 h after plasmid transfection. LX-2 cells (2 × 10⁵ cells/well) were then cultured in hepatocyte cell supernatant for 48 h before harvesting. (A-B) CoL1A1 and α-SMA mRNA expression increased in the HBV expression medium and was downregulated after the addition of Vit D₃. (C-D) The ITGBL1 promoter plasmid and HBs and HBx expression plasmids were co-transfected into HEK293T cells (96-well plate), and increasing concentrations of Vitamin D3 were added. The transcriptional activity of the ITGBL1 promoter was detected by dual-luciferase reporter assays 48 h after co-transfection. The activity of the ITGBL1 promoter decreased as the concentration of Vitamin D₃ increased. The figure shows a representative image