Renal biopsies in long-term survivors of renal transplantation: immunofluorescent studies.

Abstract

Renal biopsies of 4 patients surviving from 1 to 3 1/2 years following renal transplantation were studied with immunofluorescent techniques. Three of the 4 patients have normal renal function; the fourth patient (longest survivor in this series) has had a gradual decrease in creatinine clearance but has maintained normal blood urea nitrogen and serum creatinine levels. The patients are maintained on azathioprine and prednisone. Histologic sections were stained with specific rabbit antisera to human IgC, IgM, and C'3, and with a fluoresceinated goat anti-rabbit γ-globulin. Routine histologic preparations revealed mononuclear cell infiltration and endarteritis with endothelial proliferation of varying severity in each patient. Fluorescent anti-globulin studies demonstrated plasma cells in the interstitium and small flecks of globulin in perivascular areas and within the piled-up endothelium. Granular accumulations of gamma globulin were seen along glomerular capillary loops of the longest survivor. Small accumulations of complement were detected in similar perivascular and endothelial locations. It is suggested that antigen-antibody-complement complexes in the vessel walls may serve as an irritative stimulus to endothelial proliferation.