THE EXISTENCE AND SIGNIFICANCE OF HEPATITIS-B VIRUS-DNA IN GLOMERULONEPHRITIS

In order to investigate the role of hepatitis B virus (HBV) in the pat hogenesis of glomerulonephritis 50 cases of glomerulonephritis with HB V antigenaemia and/or hepatitis B antigen (HBAg) detected by immunohis tochemistry in renal tissue were collected. The distribution and local ization of HBV DNA were observed by using in situ hybridization. In ad dition, Southern blot analysis was performed on 23 of the 50 cases in order to reveal the state of renal HBV DNA. Thirty-six cases (72%) wer e found to be HBV DNA positive by in situ hybridization, which localiz ed in the nucleus of tubular cells. In 26 cases HBV DNA was detectable in the nucleus of glomerular mesangial and epithelial cells as well a s the mesangial matrix. Seventeen of the 23 cases were proved to be HE Y DNA positive in Southern blot analysis (82%). Three of these cases w ere identified with non-replicating free HBV DNA, while 14 cases were the integrated form. The results of this study showed that the renal t issue was infected with HBV; however, it was considered that it may be possible that the HBAg deposited on glomeruli was not only from circu lation but also from the HBV infected glomerular cells although the ev idence of this is not conclusive. In addition to the humoral immune in jury mediated by HBAg-hepatitis B antibody (HBAb) immune complexes the cellular immune injury mediated by target antigen (hepatitis B core a ntigen; HBcAg) might be also involved in the pathogenesis of HBV glome rulonephritis (GN) associated GN.