Analysis of serum autoantibodies in patients with HBV infection

Objective To investigate the condition of autoimmunity in patients infected with the hepatitis B virus(HBV).Methods Serum samples were collected from 120 HBV-infected patients and 50 healthy controls.Antinuclear antibodies(ANA) and smooth muscle antibodies(SMA) were detected by indirect immunofluorescence.Antimitochondrial antibody-M2 antigen(AMA-M2) was detected by enzyme-linked immunosorbent assay.Rheumatoid factor(RF) was detected by a scatter turbidity method.Antibodies against soluble liver antigen(SLA/LP),liver kidney microsomal(LKM-1),and liver cystosol antigen type 1(LC-1) were detected by immunoblotting.Results The positive rate autoantibodies was significantly higher in the HBV-infected patients(48.3% vs.controls: 4.0%,χ2=30.375,P0.05.However,among the HBV-infected patients,there were no significant differences in the positive rates of autoantibodies between the sub-groups of HBV carriers(40.0%),hepatitis(40.0%),hepatic sclerosis(56.7%),and hepatic cancer(56.7%)(χ2=3.337,P=0.343).ANA and RF were the most frequently detected autoantibodies.The ANA titer was mostly 1∶ 100,and the ANA pattern was mostly of the "homogeneous type" or "granular type".The liver profile(IgG) was taken for patients with ANA titer ≥1∶ 320 and as a result there were only two positive samples of AMA-M2 in the hepatic sclerosis group,indicating that HBV infection can induce autoimmune liver disease.The levels of aspartate aminotransferase were significantly different between the HBV-infected patients who were negative for autoantibodies and those who were positive for autoantibodies(P=0.007),indicating that the autoantibodies contributed to liver function damage.Conclusion HBV-infected individuals express many kinds of autoantibodies,which may promote damage to liver function and should be paid attention to by treating physicians.