[HTML][HTML] Characterization of heme as activator of Toll-like receptor 4
Heme is an ancient and ubiquitous molecule present in organisms of all kingdoms,
composed of an atom of iron linked to four ligand groups of porphyrin. A high amount of free
heme, a potential amplifier of the inflammatory response, is a characteristic feature of
diseases with increased hemolysis or extensive cell damage. Here we demonstrate that
heme, but not its analogs/precursors, induced tumor necrosis factor-α (TNF-α) secretion by
macrophages dependently on MyD88, TLR4, and CD14. The activation of TLR4 by heme is …
composed of an atom of iron linked to four ligand groups of porphyrin. A high amount of free
heme, a potential amplifier of the inflammatory response, is a characteristic feature of
diseases with increased hemolysis or extensive cell damage. Here we demonstrate that
heme, but not its analogs/precursors, induced tumor necrosis factor-α (TNF-α) secretion by
macrophages dependently on MyD88, TLR4, and CD14. The activation of TLR4 by heme is …