Browsing by Subject "Interleukin-1β"

Now showing 1 - 4 of 4
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    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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    Acidophilic granulocytes of the marine fish gilthead seabream (Sparus aurata L.) produce interleukin-1b following infection with Vibrio anguillarum
    (Springer, 2004) Chaves-Pozo, Elena; Pelegrin, Pablo; García-Castillo, Jesús; García-Ayala, Alfonsa; Mulero, Victoriano; Meseguer, José; Bioquímica y Biología Molecular B e Inmunología
    The fish immune response to Gram-negative bacteria is poorly understood. In this study, we use a monoclonal antibody (mAb) specific to acidophilic granulocytes from the marine fish gilthead seabream (Sparus aurata L.), together with an antiserum specific to interleukin-1b (IL-1b) from this species, in order to investigate whether these cells are involved in the immune response against the pathogenic bacterium Vibrio anguillarum and, in particular, in the production of the pro-inflammatory cytokine IL-1b. We found that gilthead seabream head- kidney, peritoneal exudate and peripheral blood leukocytes accumulated proIL-1b intracellularly when challenged in vitro with V. anguillarum, whereas only peritoneal exudate and blood leukocytes were able to accumulate proIL-1b following infection. Importantly, the blood leukocytes from infected animals that accumulated proIL-1b were shown to be the acidophilic granulocytes. A rapid mobilization of such cells from the head-kidney to the site of inflammation following infection with V. anguillarum was also observed.
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    NLRP3 lacking the leucine-rich repeat domain can be fully activated via the canonical inflammasome pathway
    (Nature, 2018) Hafner-Bratkovic, Iva; Susjan, Petra; Lainscek, Dusko; Tapia-Abellán, Ana; Cerovic, Kosta; Kadunc, Lucija; Angosto-Bazarra, Diego; Pelegrin, Pablo; Jerala, Roman; Bioquímica y Biología Molecular B e Inmunología
    NLRP3 is a cytosolic sensor triggered by different pathogen- and self-derived signals that plays a central role in a variety of pathological conditions, including sterile inflammation. The leucine- rich repeat domain is present in several innate immune receptors, where it is frequently responsible for sensing danger signals and regulation of activation. We show by reconstitution of truncated and chimeric variants into NLRP3-/- macrophages that the leucine-rich repeat domain is dispensable for activation and self-regulation of NLRP3 by several different triggers. The pyrin domain on the other hand is required to maintain NLRP3 in the inactive conformation. A fully responsive minimal NLRP3 truncation variant reconstituted peritonitis in NLRP3-/- mice. We demonstrate that in contrast to pathogen-activated NLRC4, the constitutively active NLRP3 molecule cannot engage wild-type NLRP3 molecules in a self-catalytic oligomerization. This lack of signal amplification is likely a protective mechanism to decrease sensitivity to endogenous triggers to impede autoinflammation.
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    The matrix synthesis and anti-inflammatory effect of autologous leukocyte-poor platelet rich plasma in human cartilage explants
    (Universidad de Murcia. Departamento de Biología Celular e Histología, 2018) Simental Mendía, Mario; Vilchez Cavazos, Félix; García Garza, Rubén; Lara Arias, Jorge; Montes de Oca Luna, Roberto; Said Fernández, Salvador; Martínez Rodríguez, Herminia G.
    Objective. To determine the effects of autologous leukocyte-poor platelet-rich plasma (LPPRP) on the expression of markers involved in cartilageextracellular matrix production and inflammation in cartilage explants bearing osteoarthritis. Materials and Methods. Cartilage explants and LP-PRP were obtained from 10 patients who underwent total knee arthroplasty. The explants were cultured in spinner flasks for 28 days in the presence of interleukin (IL)-1β and/or LP-PRP. The gene expression of catabolic (MMP13, ADAMTS5, and IL1β) and anabolic factors (COL2A1, ACAN, and SOX9) was quantified. A histological assessment was performed according to a modified Mankin score, and quantification of type II and I collagen deposition. Results. The gene expression of catabolic factors and the Mankin score were lower in LP-PRP- and LP-PRP/IL1β- than in IL-1β-treated explants, suggesting less matrix degradation in explants cultured in the presence of LP-PRP. Higher expression of genes involved in cartilage matrix restoration was observed in LP-PRP and LP-PRP/IL-1β- when compared to IL-1β-treated explants. The explants treated with LP-PRP and LPPRP/IL-1β exhibited a higher deposition of type II collagen as well as a lower deposition of type I collagen and also better surface integrity and a significant increase in the number of chondrocytes. Conclusion. LPPRP treatment favored restoration in early osteoarthritic cartilage and reduced the pro-inflammatory effect of IL1β. LP-PRP is a promising therapy for early osteoarthritis, as it promotes extracellular matrix repair, reduces inflammation, and slows cartilage degeneration.