Chronic Rejection of Renal Allografts. Part 1. Current Knowledge aboutPathogenesis

Overview

Chronic rejection is the most common cause of the long term renal graft loss. It is characterized by luminalthickening and obliteration, interstitial sclerosis, glomerulosclerosis and tubular atrophy development. The pathologyis still unclear.Alloantigen-dependent factors (acute rejection, HLA mismatch) and allograft-independent factors (ischaemia-re-perfusion, hyperlipidaemia, hypertension, infection, nephrotoxicity, reduced nephron dose) have been implicated inthe etiology of chronic rejection. As a result of these factors, endothelial cells are activated and express a variety ofadhesion molecules, cytokines and growth factors. Lymphocytes and macrophages infiltrate the areas of local damageand express other cytokines and growth factors (TGF, bFGF, PDGF). In the next step, vascular smooth muscle cellsproliferate and migrate from the media into the vascular intima and produce local extracellular matrix.Which factors are the most important and which mechanisms are the key for the development of chronic rejectionare in the focus of ongoing research.

Key words:
renal transplantation, chronic rejection