Adhesion molecule expression (ICAM-1, VCAM-1, E-selectin and PECAM) in human kidney allografts

Expression of the cellular adhesion molecules ICAM-1, VCAM-1, E-selectin and PECAM in human kidney allografts was assessed by immunoperoxidase labelling of cryostat sections. Biopsies from 10 kidneys immediately prior to transplantation and 58 biopsies from 51 kidney transplants with graft dysfunction were studied. Allograft dysfunction was due to acute tubular necrosis (n = 5), acute rejection (n = 30), cyclosporin A (CyA) nephrotoxicity (n = 6), acute pyelonephritis (n = 3), recurrent glomerulonephritis (n = 4) and chronic rejection (n = 10). There was variability in the distribution of ICAM-1, VCAM-1 and E-selectin expression in pretransplant kidneys but the principal observation was a marked increase in the expression of ICAM-1 and VCAM-1 by the renal vasculature and the proximal tubules during acute rejection. By contrast, grafts with dysfunction not attributed to rejection showed a pattern of ICAM-1 and VCAM-1 expression similar to that observed prior to transplantation. E-selectin was expressed only weakly by occasional intertubular capillaries during acute rejection but the three grafts with pyelonephritis displayed strong expression of E-selectin on intertubular capillaries. There was no change in the pattern of PECAM expression following transplantation. The induction of ICAM-1 and VCAM-1 during rejection may contribute to the recruitment of mononuclear cells and render endothelial and tubular renal cells more susceptible to cell-mediated injury.