Inhibition of αvβ6 promotes acute renal allograft rejection in nonhuman primates.

Journal Article (Journal Article)

The integrin αvβ6 activates latent transforming growth factor-β (TGF-β) within the kidney and may be a target for the prevention of chronic allograft fibrosis after kidney transplantation. However, TGF-β also has known immunosuppressive properties that are exploited by calcineurin inhibitors (CNIs); thus, the net benefit of αvβ6 inhibition remains undetermined. To assess the acute impact of interference with αvβ6 on acute rejection, we tested a humanized αvβ6-specific monoclonal antibody (STX-100) in a randomized, double-blinded, placebo-controlled nonhuman primate renal transplantation study to evaluate whether αvβ6 blockade alters the risk of acute rejection during CNI-based immunosuppression. Rhesus monkeys underwent renal allotransplantation under standard CNI-based maintenance immunosuppression; 10 biopsy-confirmed rejection-free animals were randomized to receive weekly STX-100 or placebo. Animals treated with STX-100 experienced significantly decreased rejection-free survival compared to placebo animals (p = 0.049). Immunohistochemical analysis confirmed αvβ6 ligand presence, and αvβ6 staining intensity was lower in STX-100-treated animals (p = 0.055), indicating an apparent blockade effect of STX-100. LAP, LTBP-1 and TGF-β were all decreased in animals that rejected on STX-100 compared to those that rejected on standard immunosuppression alone, suggesting a relevant effect of αvβ6 blockade on local TGF-β. These data caution against the use of αvβ6 blockade to achieve TGF-β inhibition in kidney transplantation.

Full Text

Duke Authors

Cited Authors

  • Lo, DJ; Farris, AB; Song, M; Leopardi, F; Anderson, DJ; Strobert, EA; Ramakrishnan, S; Turgeon, NA; Mehta, AK; Turnbull, B; Maroni, B; Violette, SM; Kirk, AD

Published Date

  • December 2013

Published In

Volume / Issue

  • 13 / 12

Start / End Page

  • 3085 - 3093

PubMed ID

  • 24119188

Electronic International Standard Serial Number (EISSN)

  • 1600-6143

Digital Object Identifier (DOI)

  • 10.1111/ajt.12467


  • eng

Conference Location

  • United States