title: Lymphocyte cytotoxicity to autologous hepatocytes in HBsAg positive chronic liver disease.
abstract: Lymphocytes from 39 patients with HBsAg positive chronic liver disease were incubated with their own hepatocytes to investigate mechanisms of lymphocyte-mediated liver damage. Cytotoxicity was significantly increased in 46% overall, and in 73% of those with chronic active hepatitis. Unlike HBsAg negative chronic active hepatitis where only non-T cells were cytotoxic, HBsAg positive patients had both cytotoxic T and non-T cells. A purified liver membrane complex (LSP) and aggregated IgG both blocked non-T cytotoxicity without affecting T cell cytotoxicity; this suggests that the former is probably an antibody-dependent cell-mediated reaction against normal membrane components. This was confirmed in preliminary studies which demonstrated that preincubation of hepatocytes with the F(ab)2' fragment of an anti-human IgG reduced non-T lymphocyte cytotoxicity. T-cell cytotoxicity was restricted to HBeAg-positive patients, suggesting a relationship between T-cell cytotoxicity and viral replication. Purified HBsAg, however, blocked cytotoxicity in only three of 11 cases. Non-T lymphocytes reacting with normal membrane components may contribute to liver damage in both 'autoimmune' and virus-associated chronic liver disease, whereas cytotoxic T-cells, probably reacting with viral determinants, are exclusive to those with viral replication.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000920:Antibody-Dependent Cell Cytotoxicity; D002648:Child; D002908:Chronic Disease; D003602:Cytotoxicity, Immunologic; D005260:Female; D006509:Hepatitis B / Q000276:immunology*; D006514:Hepatitis B Surface Antigens / Q000032:analysis* / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D008074:Lipoproteins / Q000276:immunology; D008099:Liver / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
chemical_list: D006514:Hepatitis B Surface Antigens; D007074:Immunoglobulin G; D008074:Lipoproteins