OBJECTIVETo investigate the effect of miR-122 on the expression of hepatitis B virus (HBV) proteins.

METHODSAnti-sense oligodeoxynucleotide (ASODN) of two different sequences against miR-122, anti-miR-122 and LNA-antimiR-122 (Locked nucleic acid), human miR -122 (hsa-miR-122), or the negative control anti-GFP were designed and synthesized, then transfected into HepG2.2.15 cells. After 24 h and 48 h, the levels of HBsAg and HBeAg in the supernatant were determined with a time-resolved immunofluorometric assay (TRFIA). HBV DNA in supernatant and miR-122 in cells were measured by quantitative real-time PCR.

RESULTSAfter 48 h expressions of miR-122 in the LNA-antimiR-122 and anti-miR-122 groups were significantly suppressed and lower than those in the negative control (P<0.001), while the level of miR-122 in the hsa-miR-122 group was higher than that in the negative control (P<0.001). The expression of HBeAg and HBsAg in hsa-miR-122 group was lower than that in the negative control (P<0.01) 24 h and 48 h after transfection. The expression of HBeAg and HBsAg in the anti-miR-122 group and LNA-antimiR-122 group was significantly lower than that in negative control (P>0.001). The levels of viral DNA at both time-points in the various test groups were not significantly different from those of negative control group (P>0.05).

CONCLUSIONmiR-122 may regulate HBV antigens and potentially affect the progress of pathogenesis, which might be the new targets for treatment of HBV infection.