Organ Transplantation Research Today is a free monthly online journal that collates and summarizes the latest research about Organ Transplantation, including details on risks, prognosis, procedure, surgery.

Antibody response against the glomerular basement membrane protein agrin in patients with transplant glomerulopathy.

Joosten SA, Sijpkens YW, van Ham V, Trouw LA, van der Vlag J, van den Heuvel B, van Kooten C, Paul LC

Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands.

Chronic allograft nephropathy (CAN) of renal allografts is still the most important cause of graft loss. A subset of these patients have transplant glomerulopathy (TGP), characterized by glomerular basement membrane (GBM) duplications, but of unknown etiology. Recently, a role for the immune system in the pathogenesis of TGP has been suggested. In 11 of 16 patients with TGP and in 3 of 16 controls with CAN in the absence of TGP we demonstrate circulating antibodies reactive with GBM isolates. The presence of anti-GBM antibodies was associated with the number of rejection episodes prior to diagnosis of TGP. Sera from the TGP patients also reacted with highly purified GBM heparan sulphate proteoglycans (HSPG). Indirect immunofluorescence with patient IgG showed a GBM-like staining pattern and colocalization with the HSPGs perlecan and especially agrin. Using patient IgG, we affinity purified the antigen and identified it as agrin. Reactivity with agrin was found in 7 of 16 (44%) of patients with TGP and in 7 of 11 (64%) patients with anti-GBM reactivity. In conclusion, we have identified a humoral response against the GBM-HSPG agrin in patients with TGP, which may play a role in the pathogenesis of TGP.

Published 12 January 2005 in Am J Transplant, 5(2): 383-93.
Full-text of this article is available online (may require subscription).

© 2004-2008 Organ Transplantation Research Today. All Rights Reserved.