The alarmin concept applied to human renal transplantation: evidence for a differential implication of HMGB1 and IL-33

PLoS One. 2014 Feb 20;9(2):e88742. doi: 10.1371/journal.pone.0088742. eCollection 2014.

Abstract

The endogenous molecules high mobility group box 1 (HMGB1) and interleukin-33 (IL-33) have been identified as alarmins, capable of mediating danger signals during tissue damage. Here, we address their possible role as innate-immune mediators in ischemia-reperfusion injury (IRI) following human kidney transplantation. We analysed serum and urinary HMGB1 and IL-33 levels, all determined by enzyme-linked immunosorbent assay, in a cohort of 26 deceased renal transplant recipients. Urinary HMGB1 and IL-33 levels were significantly increased as soon as 30 min after reperfusion, as compared to those before treatment. Moreover, both serum and urinary IL-33 (but not HMGB1) increase was positively correlated with cold ischemia time, from 30 min to 3 days post-transplantation. In vitro, human umbilical vein endothelial cells subjected to hypoxia conditions released both HMGB-1 and IL-33, while only the latter was further increased upon subsequent re-oxygenation. Finally, we postulate that leukocytes from renal recipient patients are targeted by both HMGB1 and IL-33, as suggested by increased transcription of their respective receptors (TLR2/4 and ST2L) shortly after transplantation. Consistent with this view, we found that iNKT cells, an innate-like T cell subset involved in IRI and targeted by IL-33 but not by HMGB1 was activated 1 hour post-transplantation. Altogether, these results are in keeping with a potential role of IL-33 as an innate-immune mediator during kidney IRI in humans.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Cell Hypoxia / physiology
  • Cohort Studies
  • Enzyme-Linked Immunosorbent Assay
  • Flow Cytometry
  • HMGB1 Protein / blood
  • HMGB1 Protein / metabolism*
  • HMGB1 Protein / urine
  • Human Umbilical Vein Endothelial Cells
  • Humans
  • Immunity, Innate / immunology*
  • Interleukin-33
  • Interleukins / blood
  • Interleukins / metabolism*
  • Interleukins / urine
  • Kidney Transplantation / adverse effects*
  • Middle Aged
  • Prospective Studies
  • Real-Time Polymerase Chain Reaction
  • Reperfusion Injury / etiology
  • Reperfusion Injury / immunology*
  • Statistics, Nonparametric

Substances

  • HMGB1 Protein
  • HMGB1 protein, human
  • IL33 protein, human
  • Interleukin-33
  • Interleukins

Grants and funding

This study was funded by AREN-PC (Association pour la Recherche en Néphrologie-Poitou-Charentes), INSERM, Université de Poitiers, Région Poitou-Charentes, Conseil général de la Vienne and CHU de Poitiers. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.