In situ characterization by monoclonal antibodies of the mononuclear cell infiltrate in chronic active hepatitis.

To characterize the inflammatory infiltrate of chronic active hepatitis we have examined 26 liver biopsy specimens [16 hepatitis B surface antigen-negative and 10 hepatitis B surface antigen-positive] with monoclonal antibodies and antiimmunoglobulins that react against the following mononuclear cell populations: T cells, T4 cells, T8 cells, monocytes-macrophages, Ia-positive cells, surface Ig-bearing cells, natural killer/killer cells. A biotin-avidin-fluorescein technique was used and the number of positive cells was counted in a portal tract that was more severely involved. The T cells predominate in all the specimens. The T4:T8 cell ratio and the number of T and T4 cells in the hepatitis B surface antigen-negative patients are higher than in the hepatitis B surface antigen-positive patients. While natural killer/killer cells, surface Ig-bearing cells, and macrophages are always rare, Ia-positive cells are numerous and the double-staining technique demonstrates a fair number of cells displaying both T-cell and Ia markers. These findings, while not supporting a major role of killer cells in chronic active hepatitis, suggest a different alteration of T-cell subsets in hepatitis B surface antigen-positive and -negative chronic active hepatitis.