Browsing by Subject "Caspase-1"

Now showing 1 - 2 of 2
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    Open Access
    A genetically encoded IL-1β BRET sensor to monitor inflammasome activity
    (Asociación Americana de Inmunología, 2012) Compan, Vincent; Baroja-Mazo, Alberto; Bragg, Laricia; Verkhratsky, Alexei; Perroy, Julie; Pelegrin, Pablo; Bioquímica y Biología Molecular B e Inmunología
    Inflammation is fundamental for protecting the organism against infection and injury. However, a failure to control immune response results in chronic inflammation and several associated disorders such as pain and loss of function. Initiation of inflammation is orchestrated by cytokines, among which interleukin (IL)-1β is particularly important. IL- 1β is synthesized as an inactive protein that has to be processed by the inflammasome to generate the mature bioactive form. Conventional techniques cannot monitor IL-1β activation with high spatial and temporal resolution. Here, we present a ratiometric biosensor that allows monitoring IL-1β processing in real-time, with a temporal resolution of seconds and with a single cell spatial resolution. Using this sensor, we describe for the first time the kinetic of the inflammasome activity in living macrophages. With this new probe we also demonstrated that the pro-IL-1β processing occurs all over the cytoplasm.
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    Open Access
    Chloride regulates dynamic NLRP3-dependent ASC oligomerization and inflammasome priming
    (National Academy of Sciences, 2018-09-19) Martín Sánchez, María Rosario Fátima; Pelegrín Vivancos, Pablo; Green, Jack Peter; Yu, Shi; Lopez-Castejon, Gloria; Lawrence, Catherine B.; Brough, David; Farmacología
    The NLRP3 inflammasome is an important regulator of inflammation and immunity. It is a multi-molecular platform formed within cells that facilitates the activation of pro-inflammatory caspases to drive secretion of cytokines such as IL-1β. Knowledge of the mechanisms regulating formation of the NLRP3-inflammasome is incomplete. Here we report Cl- channel dependent formation of dynamic ASC oligomers and inflammasome specks that remain inactive in the absence of K+ efflux. Formed after Cl- efflux exclusively ASC specks are NLRP3 dependent, reversible, and inactive, though they further prime inflammatory responses accelerating and enhancing release of IL-1β in response to a K+ efflux inducing stimulus. NEK7 is a specific K+ sensor and does not associate with NLRP3 under conditions stimulating exclusively Cl- efflux, but does after K+ efflux, activating the complex driving inflammation. Our investigation delivers new mechanistic understanding into inflammasome activation and the regulation of inflammatory responses.