Heme and innate immunity: new insights for an old molecule

Maria Augusta Arruda1, Aurélio V Graça-Souza, Christina Barja-Fidalgo

  • 1Departamento de Farmacologia, Instituto de Biologia Roberto Alcântara Gomes, Universidade do Estado do Rio de Janeiro, 20551-030 Rio de Janeiro, RJ, Brazil. augusta@uerj.br

Hemolytic episodes such as sickle cell disease, malaria and ischemia-reperfusion occurrence are often associated to the statement of an inflammatory response which may develop or not to a chronic inflammatory status. Although these pathological states are triggered by distinct etiological agents, all of them are associated to high levels of free heme in circulation. In this review, we aim to focus the very recent achievements that have led to the statement of free heme as a proinflammatory molecule, which may play a central role during the onset and/or persistence of inflammation during these pathologies.

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