Histological and immunological investigation of liver-specific protein (LSP) immunized rabbits compared with patients with liver disease.

In this study 45 patients with a variety of liver diseases did not demonstrate T lymphocyte sensitivity to liver-specific protein (LSP) as assessed by lymphocyte transformation whereas LSP-immunized rabbits developed both cellular and humoral immunity to this antigen. Although these LSP-immunized rabbits demonstrated portal tract inflammation with some hepatocyte necrosis, rabbits immunized with antigens known to contaminate LSP developed similar lesions. These findings contrast with those of other investigators who have reported immune responsiveness to LSP in liver patients and chronic active hepatitis in LSP-immunized rabbits. In determining the significance of these studies it must be emphasized that all preparations of LSP contain an heterogeneous group of antigens and that the specific sensitizing antigen has yet to be identified.