Abstract

After contact with material containing hepatitis-associated Australia antigen (H.A.A.), a complex set of interactions between both the related infective agent and the immune response of the host, both cellular and humoral, ensues. Evidence is presented which suggests the predominant importance of the cellular immune response in this interaction. Although immune complexes of H.A.A. and antibody are thought important in producing some of the varied clinical manifestations, the cellular immune response seems to determine the severity and persistence of the associated liver-cell damage. It is suggested that the competence of the cell-mediated (T-lymphocyte-dependent) immune system would decide whether the infection is self-limited or persists with varying degrees of liver damage.