REJECTED HUMAN RENAL ALLOGRAFTS RECOVERY AND CHARACTERISTICS OF INFILTRATING CELLS AND ANTIBODY

Abstract

Viable infiltrating host leukocytes were isolated from 10 rejected human renal allografts, removed 1-67 mo. after transplantation. Cell populations were identified by surface characteristics and their cytotoxic capacities were assessed. A heterogeneous population of cells of host origin accumulated in the grafts, including T [thymus-derived] and B [bone marrow-derived] lymphocytes, Fc+ cells and macrophages. Using a 51Cr release assay, specific cytotoxicity against donor alloantigens was determined. Cytotoxicity of the infiltrating cells was almost invariably greater than cytotoxicity mounted by recipient peripheral blood lymphocytes. Deletion studies confirmed previous work and suggested that T cells were primarily responsible for cytolysis in early acute rejection, non-T cells more often in late chronic rejection. Antibodies eluted from the grafts demonstrated specific antidonor and nonspecific activity and cross-reacting anti-HLA activity. Allograft morphology was examined and cellular and humoral host responses were assessed. Complexities of immune responses produced by the host against transplanted tissues were emphasized.