Tubular atrophy and interstitial fibrosis after renal transplantation is dependent on galectin-3

Transplantation. 2012 Mar 15;93(5):477-84. doi: 10.1097/TP.0b013e318242f40a.

Abstract

Background: Chronic allograft injury (CAI), characterized by interstitial fibrosis and tubular atrophy, leads to a progressive decline in graft function, resulting in the loss of 5% of renal transplants per annum, and eludes specific therapies. Galectin-3 (gal-3) is a β-galactoside-binding lectin expressed in diverse fibrotic tissue, and mice deficient in gal-3 have reduced fibrosis in kidney, liver, and lung models. The role of gal-3 in CAI is examined in this study.

Methods: We adopted a murine model of CAI, characterized by a single class II mismatch between BM12 donor and C57BL/6 recipient strains. Syngeneic transplants served as controls (C57BL/6). Transplants were then performed between BM12 donors and gal-3 null recipients on a C57BL/6 background.

Results: Transplantation of BM12 kidneys into C57BL6 mice was associated with interstitial fibrosis (P<0.0001), tubular atrophy (P<0.0001), and upregulation in gal-3 expression (P=0.002), compared with syngeneic controls. Transplanting BM12 kidneys into gal-3 null mice resulted in significant preservation of tubules (P=0.008) and reduced interstitial fibrosis (P=0.01), with decreased myofibroblast activation (P=0.01) and collagen I expression (P=0.04), compared with wild type controls. The number of infiltrating leukocytes was unaltered by abrogation of gal-3, but reduced expression of YM1 (P=0.0001), a marker of alternative macrophage activation, along with a reduction in the number of circulating CD4-positive T cells (P=0.01), and reduced expression of interleukin-4 (P=0.02) in gal-3 null mice suggest possible mechanisms by which gal-3 may promote renal transplant fibrosis.

Conclusion: Our results suggest a potential role for gal-3 in CAI, and this represents a potentially exciting therapeutic target.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Atrophy
  • CD4-Positive T-Lymphocytes / immunology
  • Fibrosis
  • Galectin 3 / deficiency
  • Galectin 3 / genetics
  • Galectin 3 / metabolism*
  • Graft Survival
  • Histocompatibility
  • Histocompatibility Antigens Class II / immunology
  • Interleukin-4 / metabolism
  • Kidney Diseases / immunology
  • Kidney Diseases / metabolism*
  • Kidney Diseases / pathology
  • Kidney Diseases / prevention & control
  • Kidney Transplantation / immunology*
  • Kidney Tubules / metabolism*
  • Kidney Tubules / pathology
  • Macrophage Activation
  • Macrophages / immunology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Time Factors
  • Transplantation, Isogeneic

Substances

  • Galectin 3
  • Histocompatibility Antigens Class II
  • Lgals3 protein, mouse
  • Interleukin-4