69 research outputs found
NK/iDC interaction results in IL-18 secretion by DCs at the synaptic cleft followed by NK cell activation and release of the DC maturation factor HMGB1
AbstractInteraction of natural killer (NK) cells with autologous immature dendritic cells (DCs) results in reciprocal activation; however, the underlying mechanisms are so far elusive. We show here that NK cells trigger immature DCs to polarize and secrete interleukin 18 (IL-18), a cytokine lacking a secretory leader sequence. This occurs through a Ca2+-dependent and tubulin-mediated recruitment of IL-18-containing secretory lysosomes toward the adhering NK cell. Lysosome exocytosis and IL-18 secretion are restricted at the synaptic cleft, thus allowing activation of the interacting NK cells without spreading of the cytokine. In turn, DC-activated NK cells secrete the proinflammatory cytokine high mobility group B1 (HMGB1), which induces DC maturation and protects DCs from lysis. Also HMGB1 is a leaderless cytokine that undergoes regulated secretion. Differently from IL-18, soluble HMGB1 is consistently detected in NK/DC supernatants. These data point to secretion of leaderless cytokines as a key event for the reciprocal activation of NK cells and DCs. DCs initiate NK cell activation by targeted delivery of IL-18, thus instructing NK cells in the absence of adaptive-type cytokines; in turn, activated NK cells release HMGB1, which promotes inflammation and induces DC maturation, thus favoring the onset of the adaptive immune response. (Blood. 2005;106:609-616
A persulfidation-based mechanism controls aquaporin-8 conductance
Upon engagement of tyrosine kinase receptors, nicotinamide adenine dinucleotide phosphate (NADPH)-oxidases release H2O2 in the extracellular space. We reported previously that aquaporin-8 (AQP8) transports H2O2 across the plasma membrane and is reversibly gated during cell stress, modulating signal strength and duration. We show that AQP8 gating is mediated by persulfidation of cysteine 53 (C53). Treatment with H2S is sufficient to block H2O2 entry in unstressed cells. Silencing cystathionine beta-synthase (CBS) prevents closure, suggesting that this enzyme is the main source of H2S. Molecular modeling indicates that C53 persulfidation displaces a nearby histidine located in the narrowest part of the channel. We propose that H2O2 molecules transported through AQP8 sulfenylate C53, making it susceptible to H2S produced by CBS. This mechanism tunes H2O2 transport and may control signaling and limit oxidative stress.This work was supported in part through grants from the Associazione Italiana Ricerca sul Cancro (IG 2016-18824 to R.S. and IG 2016-15434 to A.R.), the Fondazione Cariplo (2015-0591 to R.S.), the Ministero della Salute (PE-2011-02352286 to R.S. and RF-2013-02354880 to G.M.), the Telethon (GGP15059 to R.S.), and the "Cinque per mille"; (to A.R.). G.P.B. was supported by an Emmy Noether grant 1668/1-1 from the Deutsche Forschungsgemeinschaft
Randomized comparison of operator radiation exposure comparing transradial and transfemoral approach for percutaneous coronary procedures: Rationale and design of the minimizing adverse haemorrhagic events by TRansradial access site and systemic implementation of angioX - RAdiation Dose study (RAD-MATRIX)
Background: Radiation absorbed by interventional cardiologists is a frequently under-evaluated important issue. Aim is to compare radiation dose absorbed by interventional cardiologists during percutaneous coronary procedures for acute coronary syndromes comparing transradial and transfemoral access. Methods: The randomized multicentre MATRIX (Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and Systemic Implementation of angioX) trial has been designed to compare the clinical outcome of patients with acute coronary syndromes treated invasively according to the access site (transfemoral vs. transradial) and to the anticoagulant therapy (bivalirudin vs. heparin). Selected experienced interventional cardiologists involved in this study have been equipped with dedicated thermoluminescent dosimeters to evaluate the radiation dose absorbed during transfemoral or right transradial or left transradial access. For each access we evaluate the radiation dose absorbed at wrist, at thorax and at eye level. Consequently the operator is equipped with three sets (transfemoral, right transradial or left transradial access) of three different dosimeters (wrist, thorax and eye dosimet
Calmodulin-dependent kinase IV links Toll-like receptor 4 signaling with survival pathway of activated dendritic cells.
Microbial products, including lipopolysaccharide (LPS), an agonist of Toll-like receptor 4 (TLR4), regulate the lifespan of dendritic cells (DCs) by largely undefined mechanisms. Here, we identify a role for calcium-calmodulin–dependent kinase IV (CaMKIV) in this survival program. The pharmacologic inhibition of CaMKs as well as ectopic expression of kinase-inactive CaMKIV decrease the viability of monocyte-derived DCs exposed to bacterial LPS. The defect in TLR4 signaling includes a failure to accumulate the phosphorylated form of the cAMP response element-binding protein (pCREB), Bcl-2, and Bcl-xL. CaMKIV null mice have a decreased number of DCs in lymphoid tissues and fail to accumulate mature DCs in spleen on in vivo exposure to LPS. Although isolated Camk4(−/−) DCs are able to acquire the phenotype typical of mature cells and release normal amounts of cytokines in response to LPS, they fail to accumulate pCREB, Bcl-2, and Bcl-xL and therefore do not survive. The transgenic expression of Bcl-2 in CaMKIV null mice results in full recovery of DC survival in response to LPS. These results reveal a novel link between TLR4 and a calcium-dependent signaling cascade comprising CaMKIV-CREB-Bcl-2 that is essential for DC survival
The potential role of thioredoxin 1 and CD30 systems as multiple pathway targets and biomarkers in tumor therapy
Our progress in understanding pathological disease mechanisms has led to the identification of biomarkers that have had a considerable impact on clinical practice. It is hoped that the move from generalized to stratified approaches, with the grouping of patients into clinical/therapeutic subgroups according to specific biomarkers, will lead to increasingly more effective clinical treatments in the near future. This success depends on the identification of biomarkers that reflect disease evolution and can be used to predict disease state and therapy response, or represent themselves a target for treatment. Biomarkers can be identified by studying relationships between serum, tissue, or tumor microenvironment parameters and clinical or therapeutic parameters at onset and during the progression of the disease, using systems biology. Given that multiple pathways, such as those responsible for redox and immune regulation, are deregulated or altered in tumors, the future of tumor therapy could lie in the simultaneous targeting of these pathways using extracellular and intracellular targets and biomarkers. With this aim in mind, we evaluated the role of thioredoxin 1, a key redox regulator, and CD30, a cell membrane receptor, in immune regulation. Our results lead us to suggest that the combined use of these biomarkers provides more detailed information concerning the multiple pathways affected in disease and hence the possibility of more effective treatment
Consensus guidelines for the detection of immunogenic cell death
none82siApoptotic cells have long been considered as intrinsically tolerogenic or unable to elicit immune responses specific for dead cell-associated antigens. However, multiple stimuli can trigger a functionally peculiar type of apoptotic demise that does not go unnoticed by the adaptive arm of the immune system, which we named "immunogenic cell death" (ICD). ICD is preceded or accompanied by the emission of a series of immunostimulatory damage-associated molecular patterns (DAMPs) in a precise spatiotemporal configuration. Several anticancer agents that have been successfully employed in the clinic for decades, including various chemotherapeutics and radiotherapy, can elicit ICD. Moreover, defects in the components that underlie the capacity of the immune system to perceive cell death as immunogenic negatively influence disease outcome among cancer patients treated with ICD inducers. Thus, ICD has profound clinical and therapeutic implications. Unfortunately, the gold-standard approach to detect ICD relies on vaccination experiments involving immunocompetent murine models and syngeneic cancer cells, an approach that is incompatible with large screening campaigns. Here, we outline strategies conceived to detect surrogate markers of ICD in vitro and to screen large chemical libraries for putative ICD inducers, based on a high-content, high-throughput platform that we recently developed. Such a platform allows for the detection of multiple DAMPs, like cell surface-exposed calreticulin, extracellular ATP and high mobility group box 1 (HMGB1), and/or the processes that underlie their emission, such as endoplasmic reticulum stress, autophagy and necrotic plasma membrane permeabilization. We surmise that this technology will facilitate the development of next-generation anticancer regimens, which kill malignant cells and simultaneously convert them into a cancer-specific therapeutic vaccine.Kepp, Oliver; Senovilla, Laura; Vitale, Ilio; Vacchelli, Erika; Adjemian, Sandy; Agostinis, Patrizia; Apetoh, Lionel; Aranda, Fernando; Barnaba, Vincenzo; Bloy, Norma; Bracci, Laura; Breckpot, Karine; Brough, David; Buqué, Aitziber; Castro, Maria G; Cirone, Mara; Colombo, Maria I; Cremer, Isabelle; Demaria, Sandra; Dini, Luciana; Eliopoulos, Aristides G; Faggioni, Alberto; Formenti, Silvia C; Fučíková, Jitka; Gabriele, Lucia; Gaipl, Udo S; Galon, Jérôme; Garg, Abhishek; Ghiringhelli, François; Giese, Nathalia A; Guo, Zong Sheng; Hemminki, Akseli; Herrmann, Martin; Hodge, James W; Holdenrieder, Stefan; Honeychurch, Jamie; Hu, Hong-Min; Huang, Xing; Illidge, Tim M; Kono, Koji; Korbelik, Mladen; Krysko, Dmitri V; Loi, Sherene; Lowenstein, Pedro R; Lugli, Enrico; Ma, Yuting; Madeo, Frank; Manfredi, Angelo A; Martins, Isabelle; Mavilio, Domenico; Menger, Laurie; Merendino, Nicolò; Michaud, Michael; Mignot, Gregoire; Mossman, Karen L; Multhoff, Gabriele; Oehler, Rudolf; Palombo, Fabio; Panaretakis, Theocharis; Pol, Jonathan; Proietti, Enrico; Ricci, Jean-Ehrland; Riganti, Chiara; Rovere-Querini, Patrizia; Rubartelli, Anna; Sistigu, Antonella; Smyth, Mark J; Sonnemann, Juergen; Spisek, Radek; Stagg, John; Sukkurwala, Abdul Qader; Tartour, Eric; Thorburn, Andrew; Thorne, Stephen H; Vandenabeele, Peter; Velotti, Francesca; Workenhe, Samuel T; Yang, Haining; Zong, Wei-Xing; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, LorenzoKepp, Oliver; Senovilla, Laura; Vitale, Ilio; Vacchelli, Erika; Adjemian, Sandy; Agostinis, Patrizia; Apetoh, Lionel; Aranda, Fernando; Barnaba, Vincenzo; Bloy, Norma; Bracci, Laura; Breckpot, Karine; Brough, David; Buqué, Aitziber; Castro, Maria G; Cirone, Mara; Colombo, Maria I; Cremer, Isabelle; Demaria, Sandra; Dini, Luciana; Eliopoulos, Aristides G; Faggioni, Alberto; Formenti, Silvia C; Fučíková, Jitka; Gabriele, Lucia; Gaipl, Udo S; Galon, Jérôme; Garg, Abhishek; Ghiringhelli, François; Giese, Nathalia A; Guo, Zong Sheng; Hemminki, Akseli; Herrmann, Martin; Hodge, James W; Holdenrieder, Stefan; Honeychurch, Jamie; Hu, Hong Min; Huang, Xing; Illidge, Tim M; Kono, Koji; Korbelik, Mladen; Krysko, Dmitri V; Loi, Sherene; Lowenstein, Pedro R; Lugli, Enrico; Ma, Yuting; Madeo, Frank; Manfredi, Angelo A; Martins, Isabelle; Mavilio, Domenico; Menger, Laurie; Merendino, Nicolò; Michaud, Michael; Mignot, Gregoire; Mossman, Karen L; Multhoff, Gabriele; Oehler, Rudolf; Palombo, Fabio; Panaretakis, Theocharis; Pol, Jonathan; Proietti, Enrico; Ricci, Jean Ehrland; Riganti, Chiara; Rovere Querini, Patrizia; Rubartelli, Anna; Sistigu, Antonella; Smyth, Mark J; Sonnemann, Juergen; Spisek, Radek; Stagg, John; Sukkurwala, Abdul Qader; Tartour, Eric; Thorburn, Andrew; Thorne, Stephen H; Vandenabeele, Peter; Velotti, Francesca; Workenhe, Samuel T; Yang, Haining; Zong, Wei Xing; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenz
A Qualitative Exploration of the Use of Contraband Cell Phones in Secured Facilities
Offenders accepting contraband cell phones in secured facilities violate state corrections law, and the possession of these cell phones is a form of risk taking behavior. When offenders continue this risky behavior, it affects their decision making in other domains where they are challenging authorities; and may impact the length of their incarceration. This qualitative phenomenological study examined the lived experience of ex-offenders who had contraband cell phones in secured correctional facilities in order to better understand their reasons for taking risks with contraband cell phones. The theoretical foundation for this study was Trimpop\u27s risk-homeostasis and risk-motivation theories that suggest an individual\u27s behaviors adapt to negotiate between perceived risk and desired risk in order to achieve satisfaction. The research question explored beliefs and perceptions of ex-offenders who chose to accept the risk of using contraband cell phones during their time in secured facilities. Data were collected anonymously through recorded telephone interviews with 8 male adult ex-offenders and analyzed using thematic content analysis. Findings indicated participants felt empowered by possession of cell phones in prison, and it was an acceptable risk to stay connected to family out of concern for loved ones. The study contributes to social change by providing those justice system administrators, and prison managers responsible for prison cell phone policies with more detailed information about the motivations and perspectives of offenders in respect to using contraband cell phones while imprisoned in secured facilities
Production and secretion of Interleukin receptor antagonist in monocytes and in keratinocytes.
Control of interleukin-18 secretion by dendritic cells: role of calcium influxes
AbstractHere we show that dendritic cells accumulate the precursor form of the leaderless secretory protein interleukin-18 (pro-interleukin-18) in the cell cytosol and in organelles co-fractionating with endolysosomes. Upon antigen specific contact with T lymphocytes, particulated pro-interleukin-18 decreases rapidly, and the cytokine appears extracellularly, suggesting that exocytosis of pro-interleukin-18-containing organelles is induced. Exocytosis of secretory lysosomes is modulated by calcium: in agreement with this, calcium influx results in secretion of pro-interleukin-18. In turn, pro-interleukin-18 secretion induced by T cells is prevented by the calcium channel blocker nifedipine. Our results demonstrate a novel, calcium-mediated mechanism of post-translational regulation of secretion for interleukin-18, that allows a fast release of the cytokine
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