In vitro studies of enhanced IgG synthesis in severe alcoholic liver disease

Abstract

Elevated serum immunoglobulin levels are a frequent finding in patients with severe alcoholic liver disease. We measured in vitro peripheral blood lymphocyte IgA synthesis by radioimmunoassay in 13 patients with severe alcoholic liver disease and hypergammaglobulinaemia and in normal control subjects. We found an increase in spontaneous IgA synthesis compared to controls (P greater than 0.001). On the other hand, there was no difference between groups in percentage stimulation of IgG production by B cells exposed to pokeweed mitogen. We also searched for defects in concanavalin A (Con A) induced suppressor T cell activity. There was no difference between patients with alcoholic liver disease and controls in the capability of such suppressor T cells to inhibit the response of allogeneic cells to a T cell mitogen. Similarly, we examined the capability of Con A-induced suppressor T cells to inhibit pokeweed mitogen-stimulated IgG synthesis by both autologous and allogeneic responder cells and observed no difference between alcoholic patients and controls. Thus these measured suppressor T-T and T-B cell interactions appeared no different from those in control subjects. Our studies suggest, therefore, that B cell IgG synthesis in vitro is enhanced in alcoholic liver disease. Furthermore, the capability to induce suppressor T cells which affects both T and B cell function appears intact; a finding in contrast to our previous observation in chronic active hepatitis. The investigations suggest that enhanced spontaneous IgG synthesis in vitro may result from intense antigenic stimulation in vivo.