Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.22.36 (caspase-1)
 6,285 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

IL-18, a potent IFN-gamma-inducing cytokine, is expressed by various nonimmune cells as well as macrophages, suggesting that it has important physiological and immunological roles. The present study focused on the mechanism of active IL-18 induction from human oral epithelial cells. The epithelial cells and the cell lines constitutively express IL-18 mRNA and the 24-kDa precursor form of IL-18. Bioactive IL-18 exhibiting IFN-gamma-inducing activity was detected in the supernatant of the cells on costimulation with neutrophil proteinase 3 (PR3) and LPS for 24 h after IFN-gamma-priming for 3 days. An active 18-kDa form of IL-18 was detected in lysate and supernatant of the cells only after the above treatment and the induction was inhibited by cycloheximide and by serine proteinase inhibitors. After the treatment, lactate dehydrogenase activity was not detected in the cell culture supernatant, and PR3 was detected only in the membrane and not in cytoplasm fractions of the cells. Caspase-1 was not detected in the cells even after the treatment and the IL-18 induction was not inhibited by a caspase-1 inhibitor. These results suggest that the PR3-mediated induction of bioactive IL-18 secretion from oral epithelial cells in combination with LPS after IFN-gamma-priming occurred via a caspase-1-independent pathway, and provide new insight into the possible involvement of a neutrophil proteinase in the induction of bioactive IL-18 in oral inflammation such as periodontitis.
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PMID:Neutrophil proteinase 3-mediated induction of bioactive IL-18 secretion by human oral epithelial cells. 1171 26

Salmonella typhimurium invades host macrophages and can either induce a rapid cell death or establish an intracellular niche within the phagocytic vacuole. Rapid cell death requires the Salmonella pathogenicity island (SPI)1 and the host protein caspase-1, a member of the pro-apoptotic caspase family of proteases. Salmonella that do not cause this rapid cell death and instead reside in the phagocytic vacuole can trigger macrophage death at a later time point. We show here that the human pathogen Salmonella typhi also triggers both rapid, caspase-1-dependent and delayed cell death in human monocytes. The delayed cell death has previously been shown with S. typhimurium to be dependent on SPI2-encoded genes and ompR. Using caspase-1(-/-) bone marrow-derived macrophages and isogenic S. typhimurium mutant strains, we show that a large portion of the delayed, SPI2-dependent death is mediated by caspase-1. The two known substrates of activated caspase-1 are the pro-inflammatory cytokines interleukin-1beta (IL-1beta) and IL-18, which are cleaved to produce bioactive cytokines. We show here that IL-1beta is released during both SPI1- and SPI2-dependent macrophage killing. Using IL-1beta(-/-) bone marrow-derived macrophages and a neutralizing anti-IL-18 antibody, we show that neither IL-1beta nor IL-18 is required for rapid or delayed macrophage death. Thus, both rapid, SPI1-mediated killing and delayed, SPI2-mediated killing require caspase-1 and result in the secretion of IL-1beta, which promotes inflammation and may facilitate the spread of Salmonella beyond the gastrointestinal tract in systemic disease.
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PMID:Salmonella pathogenicity island 2-dependent macrophage death is mediated in part by the host cysteine protease caspase-1. 1173 94

Salmonella typhimurium invades host macrophages and can induce either an almost immediate cell death or establish an intracellular niche within the phagocytic vacuole. Rapid cell death depends on the Salmonella pathogenicity island SPI1 and the host protein caspase-1, a member of the pro-apoptotic caspase family of proteases. Caspase-1-dependent cell death leads to the activation of the potent pro-inflammatory cytokines interleukin (IL)-1beta and IL-18 to produce bioactive cytokines. Animal studies indicate that the activation of these cytokines is necessary for efficient colonization of the mouse gastrointestinal tract. Salmonella that reside in the phagocytic vacuole do not cause this early cell death and can trigger a macrophage death at a much later time point. This late-phase cell death is dependent on SPI2-encoded genes and ompR.
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PMID:Salmonella-induced macrophage death: the role of caspase-1 in death and inflammation. 1175 8

Interleukin-1 (IL-1) is a key mediator in the cytokine network, controlling important functions in the immune system, during development, infection, inflammation, cell-differentiation, tissue remodelling, and even cell death. The agonistic isoforms of IL-1 (i.e., IL-1alpha and IL-1beta), the IL-1 receptor antagonists, the receptors and receptor-associated proteins, as well as the recently identified IL-18 and its receptor belong to the IL-1 family of proteins. Activation of the IL-1beta and IL-18 precursors is performed enzymatically by caspase-1, previously termed IL-1beta-converting enzyme (ICE). This molecule is the founding member of the caspase family of enzymes, which are involved in maturation of cytokines and in initiation and execution of apoptotic processes. It has been suggested that cytokines and apoptosis are involved in pathogenesis of cardiovascular diseases such as atherosclerosis, chronic heart failure, myocarditis, cardiomyopathy, or stroke. Since IL-1, like TNF, is a central mediator in the cytokine network, it may act as a potent activator of cardiovascular cells. We know that cells of the vessel wall and the heart can produce IL-1 and respond to this mediator by production of other cytokines or regulation of other cardiovascular cell functions. Thus, this report summarizes general information about the molecules of the IL-1 family of proteins, including the caspases, as well as data regarding these proteins in relation to the vessel wall and the heart and their role in cardiovascular disease in adults and children. The summarized information indicates a role of these molecules in regulation of local inflammatory responses during cardiovascular disease.
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PMID:Interleukin-1 and related proteins in cardiovascular disease in adults and children. 1177 30

In recent years, several strategies that selectively inhibit pro-inflammatory cytokines, have yielded effective protein-based therapies for inflammatory disorders, validating the therapeutic hypothesis that intervention in cytokine signalling can provide clinical benefit. However, these protein-based products must be administered by injection, a constraint associated with inconvenience, adverse effects and expense for patients, caregivers and insurers. Besides interfering with the effects of cytokines such as TNF-alpha or IL-1beta that have already been produced, inhibition of pro-inflammatory cytokine production or signalling with low-molecular weight orally-active drugs would combine the convenience of conventional pharmaceuticals with the focused efficacy of the protein therapies. Reducing IL-1beta and IL-18 production by inhibition of IL-1beta converting enzyme (ICE, caspase-1) is one promising strategy because of the key roles of these cytokines in many inflammatory diseases. Pralnacasan, the first orally available, potent and selective ICE inhibitor to enter clinical trials, is currently under investigation in rheumatoid arthritis.
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PMID:ICE/Caspase-1 inhibitors as novel anti-inflammatory drugs. 1177 44

IL-18, which requires cleavage with caspase-1 to become active, was originally discovered as a factor that enhances IFN-gamma production from Th1 cells in the presence of anti-CD3 or anti-TcR Ab. However, it was later shown that IL-12 and IL-18 without TcR engagement can induce IFN-gamma in Th1 cells and nonpolarized T cells. Additional TcR engagement has no effect on this IFN-gamma response. Furthermore, a combination of IL-12 and IL-18 acts on B cells, NK cells, macrophages and dendritic cells to produce IFN-gamma. In contrast, IL-18 without help from IL-12 induces Th2 cytokines in T cells and NK cells. Moreover, IL-18 directly stimulates basophils and mast cells to produce Th2 cytokines and histamine independently of IgE. Most surprisingly, IL-18 causes high-level IgE production when administered to normal mice by causing CD4+ T cells to produce IL-4 and to express CD 40 ligand. We established skin-specific caspase-1 transgenic mice with elevated levels of IL-18 in their sera. We found high serum level of IgE, which is entirely dependent on stat 6 in these transgenic mice. These results indicate that caspase-1/IL-18 may be critically involved in regulation of IgE production in vivo, providing a potential therapeutic target for allergic disorders.
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PMID:[Regulation of Th1 and Th2 immune responses by IL-18]. 1190 33

The epidermal Langerhans cells (LC), a member of the dendritic cell family, and the LC-derived cytokine IL-12 play a pivotal role in the initiation of contact hypersensitivity (CHS), a Th1 immune response in the skin. Because IL-18, another LC-derived cytokine, shares functional and biological properties with IL-12, we examined a potential role for IL-18 in CHS initiation. Our studies demonstrated that during the induction phase of murine CHS, IL-18 mRNA was significantly up-regulated in the skin-draining lymph nodes (LN). Migratory hapten-modified LC in LN expressed high levels of IL-18 mRNA and secreted functional IL-18 protein. LN cells produced significant amounts of IFN-gamma following in vitro IL-12 stimulation, which could be partially blocked by anti-IL-18 Ab, suggesting a synergistic role for endogenous IL-18 in IFN-gamma production by LN cells. Because mature IL-18 requires cleavage of immature precursors by caspase-1, we further examined IL-12-induced IFN-gamma production in caspase-1(-/-) LN cells. An impaired IFN-gamma production was seen in caspase-1(-/-) LN cells, which could be restored by addition of exogenous IL-18, supporting a role for caspase-1-cleaved, mature IL-18 in IFN-gamma production. Finally, in vivo studies showed that CHS responses were significantly inhibited in mice treated with neutralizing IL-18 Ab as well as in caspase-1(-/-) mice deficient in mature IL-18, indicating functional relevance for IL-18 in CHS. Taken together, our studies demonstrate that LC-derived IL-18 significantly contributes to CHS initiation.
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PMID:Contribution of Langerhans cell-derived IL-18 to contact hypersensitivity. 1190 86

In multiple sclerosis (MS), pathological white matter damage in the central nervous system is sustained by immune-inflammatory response. Caspase-1 plays a pivotal role in immune-mediated inflammation, as it regulates the cellular export of IL-1beta and IL-18. We carried out a preliminary in vitro study of the kinetics of extracellular caspase-1 release. We then measured caspase-1 levels in paired serum and cerebrospinal fluid (CSF) samples of 75 MS patients, 15 healthy subjects, and patients with other neurological diseases. Paired synovial fluid and serum samples of patients with juvenile idiopathic arthritis, and paired sputum and serum samples of asthma patients were also studied. Mean serum caspase-1 concentrations did not differ between groups. Caspase-1 was detected in the CSF of patients with acute, but not stable, MS [7.5 +/- (SEM) 0.9 pg/ml; test's sensitivity, 56% and specificity, 100%]. Its levels correlated with pleocytosis. The highest mean caspase-1 levels were found in the arthritic synovial fluids (945.5 +/- 126.6 pg/ml, which correlated with erythrocyte sedimentation rate), and in the sputum samples (370.1 +/- 71.0 pg/ml, which correlated with the number of macrophages in the sputum). On condition that caspase-1 is determined in the fluids pertaining to the disease-specific inflammatory sites, its level is a reliable marker of ongoing immune-inflammatory response. The enzyme measurement in CSF can also help define state-trait in MS.
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PMID:Caspase-1 levels in biological fluids from patients with multiple sclerosis and from patients with other neurological and non-neurological diseases. 1195 27

Shigella flexneri infection of macrophages (MPhi) leads to activation of caspase-1 by the IpaB virulence factor, which induces rapid cell death and release of mature IL-1beta. Here we show that S. flexneri infection of human monocyte-derived dendritic cells (DC) also results in rapid IpaB-dependent death. Cytotoxicity is only partially blocked by the caspase-1 inhibitor YVAD, but completely blocked by the pan-caspase inhibitor z-VAD. Cytotoxicity is also partially blocked by glycine without affecting caspase-1-dependent IL-1beta processing, and treatment with glycine and YVAD completely blocks cytotoxicity, implying that glycine inhibits a caspase-1-independent cytotoxic mechanism. S. flexneri infection of LPS-pre-treated DC and Mphi results in comparable release of mature IL-1beta, although DC release significantly less IL-18 than MPhi. IL-1beta release from infected DC occurs within 3 h of the initial LPS pre-stimulation signal, implying that infection of DC will contribute towards induction of the early inflammatory response. The rapid death of DC during the early stages of shigellosis is likely to have adverse consequences for generation of adaptive immunity.
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PMID:Cytotoxicity and interleukin-1beta processing following Shigella flexneri infection of human monocyte-derived dendritic cells. 1198 35

Shigella dysenteriae type 1-induced apoptotic cell death in rectal tissues from patients infected with Shigella dysenteriae type 1 was studied by the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) technique and annexin V staining. Expression of proteins and cytokines participating in the apoptotic process (caspase-1, caspase-3, Fas [CD95], Fas ligand [Fas-L], perforin, granzyme A, Bax, WAF-1, Bcl-2, interleukin-2 [IL-2], IL-18, and granulocyte-macrophage colony-stimulating factor) in tissue in the acute and convalescent stages of dysentery was quantified at the single-cell level by in situ immunostaining. Apoptotic cell death in the lamina propria was markedly up-regulated at the acute stage (P < 0.05), where an increased number of necrotic cells were also seen. Phenotypic analysis of apoptotic cells revealed that 43% of T cells (CD3), 10% of granulocytes (CD15), and 5% of macrophages (CD56) underwent apoptosis. Increased activity of caspase-1 persisted in the rectum up to 1 month after onset. More-extensive expression of Fas, Fas-L, perforin, caspase-3, and IL-18, but not IL-2, at the acute stage than at the convalescent stage was observed. Increased expression of caspase-3 and IL-18 in tissues with severe inflammation compared to expression in those with mild inflammation was evident, implying a possible role in the perpetuation of inflammation. Significantly reduced cell death during convalescence was associated with a significant up-regulation of Bcl-2, Bax, and WAF-1 expression in the rectum compared to that in the acute phase of infection. Thus, induction of apoptosis at the local site in the early phase of S. dysenteriae type 1 infection was associated with a significant up-regulation of Fas/Fas-L and perforin and granzyme A expression and a down-regulation of Bcl-2 and IL-2, which promote cell survival.
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PMID:Apoptosis in acute shigellosis is associated with increased production of Fas/Fas ligand, perforin, caspase-1, and caspase-3 but reduced production of Bcl-2 and interleukin-2. 1201 Oct 15


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