M1 Macrophage Polarization Is Dependent on TRPC1-Mediated Calcium Entry.

ABSTRACT: Macrophage plasticity is essential for innate immunity, but in-depth signaling mechanism(s) regulating their functional phenotypes are ill-defined. Here we report that interferon (IFN) ? priming of naive macrophages induces store-mediated Ca2+ entry and inhibition of Ca2+ entry impairs polarization to M1 inflammatory phenotype. In vitro and in vivo functional analyses revealed ORAI1 to be a primary contributor to basal Ca2+ influx in macrophages, whereas IFN?-induced Ca2+ influx was mediated by TRPC1. Deficiency of TRPC1 displayed abrogated IFN?-induced M1 inflammatory mediators in macrophages. In a preclinical model of peritonitis by Klebsiella pneumoniae infection, macrophages showed increased Ca2+ influx, which was TRPC1 dependent. Macrophages from infected TRPC1-/- mice showed inhibited expression of M1-associated signature molecules. Furthermore, in human patients with systemic inflammatory response syndrome, the level of TRPC1 expression in circulating macrophages directly correlated with M1 inflammatory mediators. Overall, TRPC1-mediated Ca2+ influx is essential for the induction/shaping of macrophage polarization to M1 inflammatory phenotype.

SUBMITTER: Chauhan A 

PROVIDER: S-EPMC6174824 | biostudies-other | 2018 Sep

REPOSITORIES: biostudies-other