Study of cellular immunity in experimental autoimmune hepatitis in mice

This study was undertaken to produce experimental autoimmune hepatitis in mice, and to examine the role of liver specific lipoprotein (LSP), if any, and of cellular immunity in such a model. After immunization of three strains of mice (C57BL/6, C3H/He and BALB/c) with syngeneic crude liver proteins, most prominent liver changes histologically mimicking human hepatitis were produced in the liver of C57BL/6 (B6) mice. Antigenic and immunogenic activity of LSP in the crude liver proteins was decreased by the treatment of freezing and thawing, and the recovery of the antigenic activity seemed to correlate with the susceptibility of immunized mice to the induction of liver damage. Autoantibody against LSP was demonstrated in the serum of immunized B6 mice, but not in the sera of other strains after immunization. It was also found that EDTA contained in the buffer used for purification of LSP distinctly suppressed lymphocyte activity in vivo and in vitro. With the use of EDTA free LSP, it was shown that spleen cells of immunized B6 mice (especially of T cell enriched fraction) had a high reactivity studied by lymphocyte transformation test. Further examination showed that EDTA free LSP could induce mild liver lesions and lymphocyte reactivity against LSP, although neither histological change nor lymphocyte reactivity was found in the liver of B6 mice immunized with EDTA containing LSP.