Immune complexes in a renal allograft with de novo membranous nephropathy

With prolongation of survival time of renal allografts in humans, the number of reports of recurrent glomerular disease or de novo glomerulonephritis has been increasing. In most cases, the glomerulonephritis appeared to be mediated by immune complexes (ICs). By means of platelet agglutination and anti-antibody (AA) inhibition tests, we have demonstrated ICs in sera of some recipients of long-term renal allografts. Furthermore, AA absorption test demonstrated ICs deposited in 13 of 19 renal allografts which went through chronic rejection. Continuing this line of investigation, the present report describes the occurrence of the novo membranous glomerulonephritis in a renal allograft. The glomerular deposits detectable by immunofluorescent staining for IgG or C3 were completely dissociated after incubation of tissue sections with human gamma -globulin. The results of this study strongly suggested that the deposits in the graft were composed of IgG anti-IgG IC.