DOI: 10.4049/jimmunol.164.2.558 ISSN:
Cutting Edge: Heat Shock Protein 60 Is a Putative Endogenous Ligand of the Toll-Like Receptor-4 Complex
Koji Ohashi, Volker Burkart, Stefanie Flohé, Hubert Kolb- Immunology
- Immunology and Allergy
Abstract
Human heat shock protein 60 (hsp60) elicits a potent proinflammatory response in cells of the innate immune system and therefore has been proposed as a danger signal of stressed or damaged cells. We report here that macrophages of C3H/HeJ mice, carrying a mutant Toll-like-receptor (Tlr) 4 are nonresponsive to hsp60. Both the induction of TNF-α and NO formation were found dependent on a functional Tlr4 whereas stimulation of macrophages by CpG DNA was Tlr4 independent. We conclude that Tlr4 mediates hsp60 signaling. This is the first report of a putative endogenous ligand of the Tlr4 complex.