OBJECTIVE:The clearance of intrahepatic hepatitis B virus (HBV) is mainly by the cytotoxicity of immune cells with ways including CD95 ligand/CD95 induction. We found that the liver cells do express CD95 ligand (CD95L), a cytotoxic cell surface molecule. This paper studied the mechanism and implications of the hepatocytes themselves to clear the virus.
METHODS:The HepG2 cells with induced CD95L and the HepG2.2.15 cells with constitutive CD95 expression were coincubated. The apoptotic cells were examined under fluorescence microscope and with flow cytometry.
RESULTS:In chronic hepatitis B intrahepatic expressions of CD95L and/or CD95 were detected at both mRNA and protein level. Methotrexate induced CD95L expression of HepG2 cell. The HepG2 cells with CD95L could kill the HepG2.2.15 cells with CD95 molecule with apoptotic rates of 16.5% at 24h and 43.0% at 48h. This apoptosis effect could be blocked by using anti-CD95L antibody.
CONCLUSION:The hepatocyte might induce apoptosis mutually and clear the virus themselves with a nonimmune mechanism.