BM1406: Ion Channels and Immune Response toward a global understanding of immune cell physiology and for new therapeutic approaches (IONCHAN-IMMUNRESPON)

text: Neutrophils are the pivot of the cell-mediated innate immunity responsible for the killing of invading pathogens. To fulfill this role, they are able to deploy a sophisticated arsenal including release of antimicrobial enzymes during the degranulation process, production of reactive oxygen species and formation of neutrophil extracellular traps. On the other hand, neutrophils can accumulate in tissues and become inappropriately activated to secrete their cytotoxic products contributing to host tissue damage. All the defense mechanisms of neutrophils against pathogenic microorganisms have a common feature: they have been described to be governed by Ca2+ signals. The storeoperated Ca2+ entry process has been pointed as the major pathway to maintain long-lasting Ca2+ signals that regulate immune cell functions. According to current understanding, neutrophils are also able to secrete an impressive array of mediators (e.g. cytokines), which can recruit other immune cells (dendritic cells, T and B cells, natural killer cells, macrophages) and amplify the pro-inflammatory response. The related molecular mechanisms and the role of Ca2+ signalling involved in the cytokine secretion are poorly understood. Our current studies highlight the role of Orai1 channels and open new perspectives on the regulation of cytokine secretion by miRNA.