The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Albert Van Der Vliet - One of the best experts on this subject based on the ideXlab platform.
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DUOX1-dependent IL-33 secretion from the airway epithelium involves positive feedback signaling through activation of IL-33R/ST2
Free Radical Biology and Medicine, 2018Co-Authors: Christopher M. Dustin, Aida Habibovic, Milena Hristova, David E Heppner, Caspar Schiffers, Albert Van Der VlietAbstract:The airway epithelium forms a first line of defense against environmental triggers, and through secretion of epithelial cytokines, such as IL-33, presents a critical innate response mechanism to injurious insults by initiating type 2 cytokine responses. We recently demonstrated that airway epithelial IL-33 secretion depends on activation of the NADPH Oxidase Dual Oxidase 1 (DUOX1) and redox-dependent activation of the epidermal growth factor receptor (EGFR) and Src kinases. Curiously, activation of type 2 responses by direct airway administration of IL-33 was markedly diminished in DUOX1-deficient mice, suggesting DUOX1 is activated by IL-33 and participates in its downstream signaling. Furthermore, activation of epithelial IL-33 secretion in response to injury or allergens was dramatically attenuated by blockade or siRNA-mediated deletion of the IL-33 receptor (IL-33R/ST2), suggesting that epithelial IL-33 evokes a positive autocrine or paracrine feedback mechanism in which it regulates its own secretion through IL-33R/ST2-mediated signaling. Studies with human bronchial epithelial cells (H292) and primary mouse tracheal epithelial cells (MTEC) showed that IL-33 can directly trigger EGFR and Src activation and type 2 cytokine secretion, via intermediate activation of DUOX1. The activation of these kinases was shown to be associated with increased levels of DUOX1-dependent sulfenylation. Additionally, IL-33 stimulation resulted in ST2-mediated calcium-dependent extracellular secretion of ATP, a known damage signal capable of activating DUOX1. Consistent with its activation by IL-33, inhibition of Src with AZD0530 or siRNA-mediated deletion of Src led to decreased secretion of type 2 cytokines, confirming that Src plays a role in these downstream processes. Overall, our findings suggest that the role of DUOX1 in allergen-induced IL-33 secretion, and activation of type 2 responses, is largely mediated by its involvement in IL-33-dependent signaling and subsequent oxidation and activation of Src and EGFR.
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The transient receptor potential vanilloid 1 (TRPV1) channel is a critical factor in allergen-induced innate immune responses in the airway epithelium
Free Radical Biology and Medicine, 2018Co-Authors: Caspar Schiffers, Aida Habibovic, Milena Hristova, Christopher M. Dustin, Emiel F.m. Wouters, Niki L. Reynaert, Albert Van Der VlietAbstract:The airway epithelium plays a critical role in innate responses to asthma-relevant protease allergens, such as house dust mite (HDM) or Alternaria alternata (ALT), by rapid secretion of IL-1 family alarmins, such as interleukin (IL)-1α and IL-33, that orchestrate appropriate type 2 immune responses. Previous studies indicate that allergen-induced IL-33 secretion is mediated by protease-activated receptors (PAR2) and type 2 purinergic receptors (P2RY2), which induce Ca2+-dependent signaling and activation of the NADPH Oxidase Dual Oxidase 1 (DUOX1). Transient receptor potential (TRP) Ca2+ channels such as TRP Vanilloid 1 (TRPV1) are important in e.g. pain responses, often in coordination with PAR2 and P2YR2 activation, and TRPV1 has recently been implicated in asthma pathology. Using a panel of pharmacological inhibitors and activators of P2YR2, PAR2, and TRPV1, we observed that each of these receptors can provoke activation of DUOX1 and secretion of IL-33 in primary human nasal epithelial (HNE) cells. Further mechanistic studies using primary mouse tracheal epithelial cells (MTECs) or human bronchial epithelial cells (HBE1) confirmed these findings, and showed that TRPV1 contributes importantly to innate responses to HDM and ALT, and the danger signal ATP which activates P2YR2, as shown by activation of DUOX1-dependent H2O2 production, activation of epidermal growth factor receptor signaling, and rapid secretion of IL-33, which were prevented using TRPV1 antagonists or TRPV1-siRNA. Strikingly, inhibition or siRNA silencing of P2YR2 also prevented innate responses to the TRPV1 activator capsaicin, highlighting a close functional relationship of these airway epithelial surface receptors in the innate allergen responses. Finally, airway IL-33 secretion and subsequent type 2 cytokine production in mice in response to acute airway HDM challenge were markedly impaired in TRPV1-deficient mice. Overall, our studies indicate a complex relationship between various receptor types in epithelial responses to environmental triggers, and highlight the importance of TRPV1 in such epithelial responses.
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Abstract 1343: DUOX1 silencing in lung cancer is associated with enhanced nuclear EGFR localization
Molecular and Cellular Biology Genetics, 2017Co-Authors: Andrew C. Little, Milena Hristova, David E Heppner, Karamatullah Danyal, Albert Van Der VlietAbstract:Non-small cell lung cancer (NSCLC) remains to be one of the leading causes of cancer-related mortalities worldwide. The NADPH Oxidase homolog, Dual Oxidase 1 (DUOX1), is an H2O2 producing enzyme located in the airway epithelium with key roles in mucosal host defense and wound repair mechanisms. Recent studies indicate that DUOX1 is epigenetically silenced in many forms of NSCLC via hypermethylation of its promoter. We previously demonstrated that DUOX1 silencing in lung cancer cells is closely associated with epithelial-to-mesenchymal transition (EMT) and enhanced tumor invasiveness and metastasis. However, the mechanism(s) by which DUOX1 silencing promotes these outcomes are not understood. Previous findings indicate that DUOX1-dependent epithelial host defense pathways are mediated by redox-dependent activation of epithelial signaling via the non-receptor tyrosine kinase, Src, and the receptor tyrosine kinase, EGFR. We therefore hypothesized that loss of DUOX1 in lung cancer may be associated with aberrant regulation of Src and/or EGFR, tyrosine kinases that are frequently overexpressed and activated in lung cancer and strongly contribute to tumor growth and survival. In fact, recent studies have indicated that nuclear localization of EGFR in cancer cells is associated with metastatic cell behavior and poor clinical outcome, and the nuclear EGFR localization depends on Src-dependent phosphorylation of EGFR at Y1101. We observed that overexpression of DUOX1 in alveolar lung cancer A549 cells, which possess EMT-like features and in which DUOX1 is normally silenced, results in redistribution Src to the plasma membrane and decreased nuclear accumulation. DUOX1 overexpression in A549 cells also suppressed EGF-stimulated nuclear translocation of EGFR, which was associated with reduced EGFR phosphorylation at Y1101. Conversely, RNAi-mediated silencing of DUOX1 in the epithelial cancer cell line H292, which normally expresses DUOX1 expression, was found to promote EGF-mediated EGFR nuclear translocation and Y1101 phosphorylation. Since nuclear EGFR is thought to enhance the transcription of target genes related to cell cycle progression and proliferation (e.g. CDK1, Myc, others), we evaluated gene expression of these target genes in our cell models. Indeed, in cells lacking DUOX1, EGF stimulation significantly enhanced mRNA levels of CDK1, Myc, and other target genes for nuclear EGFR, whereas no such induction was seen in cells that express DUOX1. Our findings indicate that DUOX1 silencing in lung cancer may be associated with worse prognosis, partly due to altered spatiotemporal regulation of EGFR and Src and increased nuclear targeting. Since both EGFR and Src are subject to redox regulation by cysteine oxidation, we are currently aiming to elucidate the molecular mechanisms by which these mechanism are affected by altered DUOX1 status. Citation Format: Andrew C. Little, Karamathullah Danyal, David Heppner, Milena Hristova, Albert van der Vliet. DUOX1 silencing in lung cancer is associated with enhanced nuclear EGFR localization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1343. doi:10.1158/1538-7445.AM2017-1343
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Progressive loss of Dual Oxidase 1 (DUOX1) contributes to impaired airway epithelial wound responses in the aging lung
Free Radical Biology and Medicine, 2017Co-Authors: Caspar Schiffers, Aida Habibovic, Milena Hristova, Lennart K A Lundblad, Christopher M. Dustin, Albert Van Der VlietAbstract:Age-related chronic diseases, including chronic respiratory diseases such as COPD, are associated with organ function decline, impaired regenerative capacity, and immuno-senescence. Our recent studies indicate that such reparative processes in the lung are mediated by innate epithelial injury responses and production of reactive oxygen species (ROS) by the NADPH Oxidase Dual Oxidase 1 (DUOX1), which were found to be associated with oxidation and activation of epithelial tyrosine kinases, such as epidermal growth factor receptor (EGFR) and the non-receptor tyrosine kinase Src, and also with epithelial secretion of alarmins such as IL-33, which promote epithelial regeneration by activating type 2 immune responses. Contrasting the common belief that aging is associated with increased ROS production, we observed that DUOX1 expression in mouse lungs markedly decreases with age. Moreover, we noticed that DUOX1-deficient mice display accelerated age-related decline in lung function and features of emphysema, as shown by airspace enlargement and increased lung compliance. We hypothesized that loss of DUOX1 may contribute to other features of lung aging, but aged-related lung changes such as increased parenchymal collagen deposition, molecular indices of senescence, or tissue levels of pro-inflammatory cytokines, were all largely unaltered in DUOX1-deficient mice. However, we observed that aged mice display markedly attenuated innate airway responses to inhaled allergens, as illustrated by diminished secretion of IL-33 and other related cytokines. Similar findings were observed in vitro using cultured mouse tracheal epithelial cells (MTEC), in which MTECs from older mice showed dramatically reduced innate responses to injury, which was associated with reduced oxidation and activation of Src and EGFR. Consistent with a potential age-related suppression of DUOX1 by epigenetic mechanisms such as promoter hypermethylation, allergen-induced IL-33 secretion in MTECs from aged mice could be rescued by treatment with the DNA methyltransferase inhibitor AzdC. Overall, these results underline the importance of DUOX1 in airway host defense and regenerative capacity, and indicate that age-related loss of DUOX1 contributes to accelerated impairment of epithelial regenerative capacity and air-space enlargement.
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Airway Epithelial IL-33 Secretion and Feedback Signaling is Associated with Redox Activation of Src Kinase
Free Radical Biology and Medicine, 2017Co-Authors: Christopher M. Dustin, Aida Habibovic, Milena Hristova, David E Heppner, Caspar Schiffers, Albert Van Der VlietAbstract:The airway epithelium forms the primary defense against inhaled allergens and environmental insults to the respiratory system. Aside from acting as a physical barrier, the epithelium also signals for reparative and inflammatory responses by generating various epithelial-derived cytokines and mediators. Chief among these is the epithelial secretion of the alarmin cytokine IL-33, which in turn induces type 2 immune responses. Although these processes serve a protective mechanism by promoting epithelial regenerative pathways, chronic activation of such type 2 responses contribute to chronic respiratory diseases such as asthma and COPD. We recently demonstrated that epithelial IL-33 secretion in response to various injurious triggers is dependent on H2O2 production by the NADPH Oxidase Dual Oxidase 1 (DUOX1), and that this was associated with activation and oxidation of the non-receptor tyrosine kinase Src. However, the precise role of Src in these responses is still unclear, and we hypothesized that redox-dependent activation of Src is critical for increased IL-33 secretion and downstream type 2 responses to allergens. Pretreatment of mice with the Src family kinase inhibitor AZD0530 was found to significantly attenuate epithelial Src activation, as well as expression and secretion of IL-33 and the downstream type 2 cytokines IL-5 and IL-13, in response to acute challenge with house dust mite (HDM). Similar findings were obtained using isolated mouse tracheal epithelial cells (MTEC), in which siRNA-dependent silencing of Src resulted in diminished HDM-induced production of IL-33, as well as IL-5 and IL-13. Interestingly, we noted that HDM-induced IL-33 secretion is diminished upon blockade of the IL-33 receptor ST2, suggesting that IL-33 regulates its own secretion through a positive feedback mechanism. Indeed, induction of type 2 cytokine secretion (IL-13) in airway epithelial cells by direct stimulation with IL-33 was found to be DUOX1-dependent, and associated with increased H2O2 production and activation/oxidation of Src. Building on our recent findings that DUOX1-dependent activation of Src involves oxidation of its C185 and C277 residues, preliminary studies using H292 lung epithelial cells transfected with C185A or C277A Src variants indicate that expression of these variants leads to suppressed HDM-induced IL-33 secretion. Overall, our studies identify Src as a critical mediator of allergen-induced IL-33 secretion and innate type 2 immune responses, and highlight the importance of various redox-sensitive Cys residues in these responses.
Milena Hristova - One of the best experts on this subject based on the ideXlab platform.
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Downregulation of epithelial DUOX1 in chronic obstructive pulmonary disease
JCI insight, 2021Co-Authors: Caspar Schiffers, Aida Habibovic, Milena Hristova, Christopher M. Dustin, Cheryl Van De Wetering, Robert A Bauer, Sara Lambrichts, Pamela M. Vacek, Emiel F.m. Wouters, Niki L. ReynaertAbstract:Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease characterized by small airway remodeling and alveolar emphysema due to environmental stresses such as cigarette smoking (CS). Oxidative stress is commonly implicated in COPD pathology, but recent findings suggest that one oxidant-producing NADPH Oxidase homolog, Dual Oxidase 1 (DUOX1), is downregulated in the airways of patients with COPD. We evaluated lung tissue sections from patients with COPD for small airway epithelial DUOX1 protein expression, in association with measures of lung function and small airway and alveolar remodeling. We also addressed the impact of DUOX1 for lung tissue remodeling in mouse models of COPD. Small airway DUOX1 levels were decreased in advanced COPD and correlated with loss of lung function and markers of emphysema and remodeling. Similarly, DUOX1 downregulation in correlation with extracellular matrix remodeling was observed in a genetic model of COPD, transgenic SPC-TNF-α mice. Finally, development of subepithelial airway fibrosis in mice due to exposure to the CS-component acrolein, or alveolar emphysema induced by administration of elastase, were in both cases exacerbated in Duox1-deficient mice. Collectively, our studies highlight that downregulation of DUOX1 may be a contributing feature of COPD pathogenesis, likely related to impaired DUOX1-mediated innate injury responses involved in epithelial homeostasis.
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DUOX1-dependent IL-33 secretion from the airway epithelium involves positive feedback signaling through activation of IL-33R/ST2
Free Radical Biology and Medicine, 2018Co-Authors: Christopher M. Dustin, Aida Habibovic, Milena Hristova, David E Heppner, Caspar Schiffers, Albert Van Der VlietAbstract:The airway epithelium forms a first line of defense against environmental triggers, and through secretion of epithelial cytokines, such as IL-33, presents a critical innate response mechanism to injurious insults by initiating type 2 cytokine responses. We recently demonstrated that airway epithelial IL-33 secretion depends on activation of the NADPH Oxidase Dual Oxidase 1 (DUOX1) and redox-dependent activation of the epidermal growth factor receptor (EGFR) and Src kinases. Curiously, activation of type 2 responses by direct airway administration of IL-33 was markedly diminished in DUOX1-deficient mice, suggesting DUOX1 is activated by IL-33 and participates in its downstream signaling. Furthermore, activation of epithelial IL-33 secretion in response to injury or allergens was dramatically attenuated by blockade or siRNA-mediated deletion of the IL-33 receptor (IL-33R/ST2), suggesting that epithelial IL-33 evokes a positive autocrine or paracrine feedback mechanism in which it regulates its own secretion through IL-33R/ST2-mediated signaling. Studies with human bronchial epithelial cells (H292) and primary mouse tracheal epithelial cells (MTEC) showed that IL-33 can directly trigger EGFR and Src activation and type 2 cytokine secretion, via intermediate activation of DUOX1. The activation of these kinases was shown to be associated with increased levels of DUOX1-dependent sulfenylation. Additionally, IL-33 stimulation resulted in ST2-mediated calcium-dependent extracellular secretion of ATP, a known damage signal capable of activating DUOX1. Consistent with its activation by IL-33, inhibition of Src with AZD0530 or siRNA-mediated deletion of Src led to decreased secretion of type 2 cytokines, confirming that Src plays a role in these downstream processes. Overall, our findings suggest that the role of DUOX1 in allergen-induced IL-33 secretion, and activation of type 2 responses, is largely mediated by its involvement in IL-33-dependent signaling and subsequent oxidation and activation of Src and EGFR.
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The transient receptor potential vanilloid 1 (TRPV1) channel is a critical factor in allergen-induced innate immune responses in the airway epithelium
Free Radical Biology and Medicine, 2018Co-Authors: Caspar Schiffers, Aida Habibovic, Milena Hristova, Christopher M. Dustin, Emiel F.m. Wouters, Niki L. Reynaert, Albert Van Der VlietAbstract:The airway epithelium plays a critical role in innate responses to asthma-relevant protease allergens, such as house dust mite (HDM) or Alternaria alternata (ALT), by rapid secretion of IL-1 family alarmins, such as interleukin (IL)-1α and IL-33, that orchestrate appropriate type 2 immune responses. Previous studies indicate that allergen-induced IL-33 secretion is mediated by protease-activated receptors (PAR2) and type 2 purinergic receptors (P2RY2), which induce Ca2+-dependent signaling and activation of the NADPH Oxidase Dual Oxidase 1 (DUOX1). Transient receptor potential (TRP) Ca2+ channels such as TRP Vanilloid 1 (TRPV1) are important in e.g. pain responses, often in coordination with PAR2 and P2YR2 activation, and TRPV1 has recently been implicated in asthma pathology. Using a panel of pharmacological inhibitors and activators of P2YR2, PAR2, and TRPV1, we observed that each of these receptors can provoke activation of DUOX1 and secretion of IL-33 in primary human nasal epithelial (HNE) cells. Further mechanistic studies using primary mouse tracheal epithelial cells (MTECs) or human bronchial epithelial cells (HBE1) confirmed these findings, and showed that TRPV1 contributes importantly to innate responses to HDM and ALT, and the danger signal ATP which activates P2YR2, as shown by activation of DUOX1-dependent H2O2 production, activation of epidermal growth factor receptor signaling, and rapid secretion of IL-33, which were prevented using TRPV1 antagonists or TRPV1-siRNA. Strikingly, inhibition or siRNA silencing of P2YR2 also prevented innate responses to the TRPV1 activator capsaicin, highlighting a close functional relationship of these airway epithelial surface receptors in the innate allergen responses. Finally, airway IL-33 secretion and subsequent type 2 cytokine production in mice in response to acute airway HDM challenge were markedly impaired in TRPV1-deficient mice. Overall, our studies indicate a complex relationship between various receptor types in epithelial responses to environmental triggers, and highlight the importance of TRPV1 in such epithelial responses.
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Abstract 1343: DUOX1 silencing in lung cancer is associated with enhanced nuclear EGFR localization
Molecular and Cellular Biology Genetics, 2017Co-Authors: Andrew C. Little, Milena Hristova, David E Heppner, Karamatullah Danyal, Albert Van Der VlietAbstract:Non-small cell lung cancer (NSCLC) remains to be one of the leading causes of cancer-related mortalities worldwide. The NADPH Oxidase homolog, Dual Oxidase 1 (DUOX1), is an H2O2 producing enzyme located in the airway epithelium with key roles in mucosal host defense and wound repair mechanisms. Recent studies indicate that DUOX1 is epigenetically silenced in many forms of NSCLC via hypermethylation of its promoter. We previously demonstrated that DUOX1 silencing in lung cancer cells is closely associated with epithelial-to-mesenchymal transition (EMT) and enhanced tumor invasiveness and metastasis. However, the mechanism(s) by which DUOX1 silencing promotes these outcomes are not understood. Previous findings indicate that DUOX1-dependent epithelial host defense pathways are mediated by redox-dependent activation of epithelial signaling via the non-receptor tyrosine kinase, Src, and the receptor tyrosine kinase, EGFR. We therefore hypothesized that loss of DUOX1 in lung cancer may be associated with aberrant regulation of Src and/or EGFR, tyrosine kinases that are frequently overexpressed and activated in lung cancer and strongly contribute to tumor growth and survival. In fact, recent studies have indicated that nuclear localization of EGFR in cancer cells is associated with metastatic cell behavior and poor clinical outcome, and the nuclear EGFR localization depends on Src-dependent phosphorylation of EGFR at Y1101. We observed that overexpression of DUOX1 in alveolar lung cancer A549 cells, which possess EMT-like features and in which DUOX1 is normally silenced, results in redistribution Src to the plasma membrane and decreased nuclear accumulation. DUOX1 overexpression in A549 cells also suppressed EGF-stimulated nuclear translocation of EGFR, which was associated with reduced EGFR phosphorylation at Y1101. Conversely, RNAi-mediated silencing of DUOX1 in the epithelial cancer cell line H292, which normally expresses DUOX1 expression, was found to promote EGF-mediated EGFR nuclear translocation and Y1101 phosphorylation. Since nuclear EGFR is thought to enhance the transcription of target genes related to cell cycle progression and proliferation (e.g. CDK1, Myc, others), we evaluated gene expression of these target genes in our cell models. Indeed, in cells lacking DUOX1, EGF stimulation significantly enhanced mRNA levels of CDK1, Myc, and other target genes for nuclear EGFR, whereas no such induction was seen in cells that express DUOX1. Our findings indicate that DUOX1 silencing in lung cancer may be associated with worse prognosis, partly due to altered spatiotemporal regulation of EGFR and Src and increased nuclear targeting. Since both EGFR and Src are subject to redox regulation by cysteine oxidation, we are currently aiming to elucidate the molecular mechanisms by which these mechanism are affected by altered DUOX1 status. Citation Format: Andrew C. Little, Karamathullah Danyal, David Heppner, Milena Hristova, Albert van der Vliet. DUOX1 silencing in lung cancer is associated with enhanced nuclear EGFR localization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1343. doi:10.1158/1538-7445.AM2017-1343
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Progressive loss of Dual Oxidase 1 (DUOX1) contributes to impaired airway epithelial wound responses in the aging lung
Free Radical Biology and Medicine, 2017Co-Authors: Caspar Schiffers, Aida Habibovic, Milena Hristova, Lennart K A Lundblad, Christopher M. Dustin, Albert Van Der VlietAbstract:Age-related chronic diseases, including chronic respiratory diseases such as COPD, are associated with organ function decline, impaired regenerative capacity, and immuno-senescence. Our recent studies indicate that such reparative processes in the lung are mediated by innate epithelial injury responses and production of reactive oxygen species (ROS) by the NADPH Oxidase Dual Oxidase 1 (DUOX1), which were found to be associated with oxidation and activation of epithelial tyrosine kinases, such as epidermal growth factor receptor (EGFR) and the non-receptor tyrosine kinase Src, and also with epithelial secretion of alarmins such as IL-33, which promote epithelial regeneration by activating type 2 immune responses. Contrasting the common belief that aging is associated with increased ROS production, we observed that DUOX1 expression in mouse lungs markedly decreases with age. Moreover, we noticed that DUOX1-deficient mice display accelerated age-related decline in lung function and features of emphysema, as shown by airspace enlargement and increased lung compliance. We hypothesized that loss of DUOX1 may contribute to other features of lung aging, but aged-related lung changes such as increased parenchymal collagen deposition, molecular indices of senescence, or tissue levels of pro-inflammatory cytokines, were all largely unaltered in DUOX1-deficient mice. However, we observed that aged mice display markedly attenuated innate airway responses to inhaled allergens, as illustrated by diminished secretion of IL-33 and other related cytokines. Similar findings were observed in vitro using cultured mouse tracheal epithelial cells (MTEC), in which MTECs from older mice showed dramatically reduced innate responses to injury, which was associated with reduced oxidation and activation of Src and EGFR. Consistent with a potential age-related suppression of DUOX1 by epigenetic mechanisms such as promoter hypermethylation, allergen-induced IL-33 secretion in MTECs from aged mice could be rescued by treatment with the DNA methyltransferase inhibitor AzdC. Overall, these results underline the importance of DUOX1 in airway host defense and regenerative capacity, and indicate that age-related loss of DUOX1 contributes to accelerated impairment of epithelial regenerative capacity and air-space enlargement.
Sofia De Oliveira - One of the best experts on this subject based on the ideXlab platform.
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Hydrogen peroxide in neutrophil inflammation: Lesson from the zebrafish
Developmental and comparative immunology, 2019Co-Authors: Francisco J. Martínez-navarro, Sofia De Oliveira, Sergio Candel, Raúl Corbalán-vélez, Francisco J. Martínez-morcillo, Isabel Cabas, Alfonsa García-ayala, Teresa Martínez-menchón, Pablo Mesa-del-castillo, Maria L CayuelaAbstract:The zebrafish has become an excellent model for the study of inflammation and immunity. Its unique advantages for in vivo imaging and gene and drug screening have allowed the visualization of Dual Oxidase 1 (Duox1)-derived hydrogen peroxide (H2O2) tissue gradients and its crosstalk with neutrophil infiltration to inflamed tissue. Thus, it has been shown that H2O2 directly recruits neutrophils via the Src-family tyrosine kinase Lyn and indirectly by the activation of several signaling pathways involved in inflammation, such as nuclear factor κB (NF-κB), mitogen activated kinases and the transcription factor AP1. In addition, this model has also unmasked the unexpected ability of H2O2 to induce the expression of the gene encoding the key neutrophil chemoattractant CXC chemokine ligand 8 by facilitating the accessibility of transcription factors to its promoter through histone covalent modifications. Finally, zebrafish models of psoriasis have shown that a H2O2/NF-κB/Duox1 positive feedback inflammatory loop operates in this chronic inflammatory disorder and that pharmacological inhibition of Duox1, but not of downstream mediators, inhibits inflammation and restores epithelial homeostasis. Therefore, these results have pointed out DUOX1 and H2O2 as therapeutic targets for the treatment of skin inflammatory disorders, such as psoriasis.
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ATP Modulates Acute Inflammation In Vivo through Dual Oxidase 1–Derived H2O2 Production and NF-κB Activation
Journal of immunology (Baltimore Md. : 1950), 2014Co-Authors: Sofia De Oliveira, Azucena López-muñoz, Sergio Candel, Pablo Pelegrín, Ângelo Calado, Victoriano MuleroAbstract:Dual Oxidase 1 (Duox1) is the NADPH Oxidase responsible for the H2O2 gradient formed in tissues after injury to trigger the early recruitment of leukocytes. Little is known about the signals that modulate H2O2 release from DUOX1 and whether the H2O2 gradient can orchestrate the inflammatory response in vivo. In this study, we report on a dominant-negative form of zebrafish Duox1 that is able to inhibit endogenous Duox1 activity, H2O2 release and leukocyte recruitment after tissue injury, with none of the side effects associated with morpholino-mediated Duox1 knockdown. Using this specific tool, we found that ATP release following tissue injury activates purinergic P2Y receptors, and modulates Duox1 activity through phospholipase C (PLC) and intracellular calcium signaling in vivo. Furthermore, Duox1-derived H2O2 is able to trigger the NF-κB inflammatory signaling pathway. These data reveal that extracellular ATP acting as an early danger signal is responsible for the activation of Duox1 via a P2YR/PLC/Ca2+ signaling pathway and the production of H2O2, which, in turn, is able to modulate in vivo not only the early recruitment of leukocytes to the wound but also the inflammatory response through activation of the NF-κB signaling pathway.
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tnfa signaling through tnfr2 protects skin against oxidative stress induced inflammation
PLOS Biology, 2014Co-Authors: Sergio Candel, Sofia De Oliveira, Azucena Lopezmunoz, Diana Garciamoreno, Raquel Espinpalazon, Sylwia D Tyrkalska, Maria L Cayuela, Stephen A RenshawAbstract:TNFα overexpression has been associated with several chronic inflammatory diseases, including psoriasis, lichen planus, rheumatoid arthritis, and inflammatory bowel disease. Paradoxically, numerous studies have reported new-onset psoriasis and lichen planus following TNFα antagonist therapy. Here, we show that genetic inhibition of Tnfa and Tnfr2 in zebrafish results in the mobilization of neutrophils to the skin. Using combinations of fluorescent reporter transgenes, fluorescence microscopy, and flow cytometry, we identified the local production of Dual Oxidase 1 (Duox1)-derived H2O2 by Tnfa- and Tnfr2-deficient keratinocytes as a trigger for the activation of the master inflammation transcription factor NF-κB, which then promotes the induction of genes encoding pro-inflammatory molecules. In addition, pharmacological inhibition of Duox1 completely abrogated skin inflammation, placing Duox1-derived H2O2 upstream of this positive feedback inflammatory loop. Strikingly, DUOX1 was drastically induced in the skin lesions of psoriasis and lichen planus patients. These results reveal a crucial role for TNFα/TNFR2 axis in the protection of the skin against DUOX1-mediated oxidative stress and could establish new therapeutic targets for skin inflammatory disorders.
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Tnfa Signaling Through Tnfr2 Protects Skin Against Oxidative Stress–Induced Inflammation
PLoS biology, 2014Co-Authors: Sergio Candel, Sofia De Oliveira, Azucena López-muñoz, Sylwia D Tyrkalska, Maria L Cayuela, Stephen A Renshaw, Diana García-moreno, Raquel Espín-palazón, Raúl Corbalán-vélez, Inmaculada Vidal-abarcaAbstract:TNFα overexpression has been associated with several chronic inflammatory diseases, including psoriasis, lichen planus, rheumatoid arthritis, and inflammatory bowel disease. Paradoxically, numerous studies have reported new-onset psoriasis and lichen planus following TNFα antagonist therapy. Here, we show that genetic inhibition of Tnfa and Tnfr2 in zebrafish results in the mobilization of neutrophils to the skin. Using combinations of fluorescent reporter transgenes, fluorescence microscopy, and flow cytometry, we identified the local production of Dual Oxidase 1 (Duox1)-derived H₂O₂ by Tnfa- and Tnfr2-deficient keratinocytes as a trigger for the activation of the master inflammation transcription factor NF-κB, which then promotes the induction of genes encoding pro-inflammatory molecules. In addition, pharmacological inhibition of Duox1 completely abrogated skin inflammation, placing Duox1-derived H₂O₂ upstream of this positive feedback inflammatory loop. Strikingly, DUOX1 was drastically induced in the skin lesions of psoriasis and lichen planus patients. These results reveal a crucial role for TNFα/TNFR2 axis in the protection of the skin against DUOX1-mediated oxidative stress and could establish new therapeutic targets for skin inflammatory disorders.
Sergio Candel - One of the best experts on this subject based on the ideXlab platform.
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Hydrogen peroxide in neutrophil inflammation: Lesson from the zebrafish
Developmental and comparative immunology, 2019Co-Authors: Francisco J. Martínez-navarro, Sofia De Oliveira, Sergio Candel, Raúl Corbalán-vélez, Francisco J. Martínez-morcillo, Isabel Cabas, Alfonsa García-ayala, Teresa Martínez-menchón, Pablo Mesa-del-castillo, Maria L CayuelaAbstract:The zebrafish has become an excellent model for the study of inflammation and immunity. Its unique advantages for in vivo imaging and gene and drug screening have allowed the visualization of Dual Oxidase 1 (Duox1)-derived hydrogen peroxide (H2O2) tissue gradients and its crosstalk with neutrophil infiltration to inflamed tissue. Thus, it has been shown that H2O2 directly recruits neutrophils via the Src-family tyrosine kinase Lyn and indirectly by the activation of several signaling pathways involved in inflammation, such as nuclear factor κB (NF-κB), mitogen activated kinases and the transcription factor AP1. In addition, this model has also unmasked the unexpected ability of H2O2 to induce the expression of the gene encoding the key neutrophil chemoattractant CXC chemokine ligand 8 by facilitating the accessibility of transcription factors to its promoter through histone covalent modifications. Finally, zebrafish models of psoriasis have shown that a H2O2/NF-κB/Duox1 positive feedback inflammatory loop operates in this chronic inflammatory disorder and that pharmacological inhibition of Duox1, but not of downstream mediators, inhibits inflammation and restores epithelial homeostasis. Therefore, these results have pointed out DUOX1 and H2O2 as therapeutic targets for the treatment of skin inflammatory disorders, such as psoriasis.
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ATP Modulates Acute Inflammation In Vivo through Dual Oxidase 1–Derived H2O2 Production and NF-κB Activation
Journal of immunology (Baltimore Md. : 1950), 2014Co-Authors: Sofia De Oliveira, Azucena López-muñoz, Sergio Candel, Pablo Pelegrín, Ângelo Calado, Victoriano MuleroAbstract:Dual Oxidase 1 (Duox1) is the NADPH Oxidase responsible for the H2O2 gradient formed in tissues after injury to trigger the early recruitment of leukocytes. Little is known about the signals that modulate H2O2 release from DUOX1 and whether the H2O2 gradient can orchestrate the inflammatory response in vivo. In this study, we report on a dominant-negative form of zebrafish Duox1 that is able to inhibit endogenous Duox1 activity, H2O2 release and leukocyte recruitment after tissue injury, with none of the side effects associated with morpholino-mediated Duox1 knockdown. Using this specific tool, we found that ATP release following tissue injury activates purinergic P2Y receptors, and modulates Duox1 activity through phospholipase C (PLC) and intracellular calcium signaling in vivo. Furthermore, Duox1-derived H2O2 is able to trigger the NF-κB inflammatory signaling pathway. These data reveal that extracellular ATP acting as an early danger signal is responsible for the activation of Duox1 via a P2YR/PLC/Ca2+ signaling pathway and the production of H2O2, which, in turn, is able to modulate in vivo not only the early recruitment of leukocytes to the wound but also the inflammatory response through activation of the NF-κB signaling pathway.
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tnfa signaling through tnfr2 protects skin against oxidative stress induced inflammation
PLOS Biology, 2014Co-Authors: Sergio Candel, Sofia De Oliveira, Azucena Lopezmunoz, Diana Garciamoreno, Raquel Espinpalazon, Sylwia D Tyrkalska, Maria L Cayuela, Stephen A RenshawAbstract:TNFα overexpression has been associated with several chronic inflammatory diseases, including psoriasis, lichen planus, rheumatoid arthritis, and inflammatory bowel disease. Paradoxically, numerous studies have reported new-onset psoriasis and lichen planus following TNFα antagonist therapy. Here, we show that genetic inhibition of Tnfa and Tnfr2 in zebrafish results in the mobilization of neutrophils to the skin. Using combinations of fluorescent reporter transgenes, fluorescence microscopy, and flow cytometry, we identified the local production of Dual Oxidase 1 (Duox1)-derived H2O2 by Tnfa- and Tnfr2-deficient keratinocytes as a trigger for the activation of the master inflammation transcription factor NF-κB, which then promotes the induction of genes encoding pro-inflammatory molecules. In addition, pharmacological inhibition of Duox1 completely abrogated skin inflammation, placing Duox1-derived H2O2 upstream of this positive feedback inflammatory loop. Strikingly, DUOX1 was drastically induced in the skin lesions of psoriasis and lichen planus patients. These results reveal a crucial role for TNFα/TNFR2 axis in the protection of the skin against DUOX1-mediated oxidative stress and could establish new therapeutic targets for skin inflammatory disorders.
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Tnfa Signaling Through Tnfr2 Protects Skin Against Oxidative Stress–Induced Inflammation
PLoS biology, 2014Co-Authors: Sergio Candel, Sofia De Oliveira, Azucena López-muñoz, Sylwia D Tyrkalska, Maria L Cayuela, Stephen A Renshaw, Diana García-moreno, Raquel Espín-palazón, Raúl Corbalán-vélez, Inmaculada Vidal-abarcaAbstract:TNFα overexpression has been associated with several chronic inflammatory diseases, including psoriasis, lichen planus, rheumatoid arthritis, and inflammatory bowel disease. Paradoxically, numerous studies have reported new-onset psoriasis and lichen planus following TNFα antagonist therapy. Here, we show that genetic inhibition of Tnfa and Tnfr2 in zebrafish results in the mobilization of neutrophils to the skin. Using combinations of fluorescent reporter transgenes, fluorescence microscopy, and flow cytometry, we identified the local production of Dual Oxidase 1 (Duox1)-derived H₂O₂ by Tnfa- and Tnfr2-deficient keratinocytes as a trigger for the activation of the master inflammation transcription factor NF-κB, which then promotes the induction of genes encoding pro-inflammatory molecules. In addition, pharmacological inhibition of Duox1 completely abrogated skin inflammation, placing Duox1-derived H₂O₂ upstream of this positive feedback inflammatory loop. Strikingly, DUOX1 was drastically induced in the skin lesions of psoriasis and lichen planus patients. These results reveal a crucial role for TNFα/TNFR2 axis in the protection of the skin against DUOX1-mediated oxidative stress and could establish new therapeutic targets for skin inflammatory disorders.
Aida Habibovic - One of the best experts on this subject based on the ideXlab platform.
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Downregulation of epithelial DUOX1 in chronic obstructive pulmonary disease
JCI insight, 2021Co-Authors: Caspar Schiffers, Aida Habibovic, Milena Hristova, Christopher M. Dustin, Cheryl Van De Wetering, Robert A Bauer, Sara Lambrichts, Pamela M. Vacek, Emiel F.m. Wouters, Niki L. ReynaertAbstract:Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease characterized by small airway remodeling and alveolar emphysema due to environmental stresses such as cigarette smoking (CS). Oxidative stress is commonly implicated in COPD pathology, but recent findings suggest that one oxidant-producing NADPH Oxidase homolog, Dual Oxidase 1 (DUOX1), is downregulated in the airways of patients with COPD. We evaluated lung tissue sections from patients with COPD for small airway epithelial DUOX1 protein expression, in association with measures of lung function and small airway and alveolar remodeling. We also addressed the impact of DUOX1 for lung tissue remodeling in mouse models of COPD. Small airway DUOX1 levels were decreased in advanced COPD and correlated with loss of lung function and markers of emphysema and remodeling. Similarly, DUOX1 downregulation in correlation with extracellular matrix remodeling was observed in a genetic model of COPD, transgenic SPC-TNF-α mice. Finally, development of subepithelial airway fibrosis in mice due to exposure to the CS-component acrolein, or alveolar emphysema induced by administration of elastase, were in both cases exacerbated in Duox1-deficient mice. Collectively, our studies highlight that downregulation of DUOX1 may be a contributing feature of COPD pathogenesis, likely related to impaired DUOX1-mediated innate injury responses involved in epithelial homeostasis.
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DUOX1-dependent IL-33 secretion from the airway epithelium involves positive feedback signaling through activation of IL-33R/ST2
Free Radical Biology and Medicine, 2018Co-Authors: Christopher M. Dustin, Aida Habibovic, Milena Hristova, David E Heppner, Caspar Schiffers, Albert Van Der VlietAbstract:The airway epithelium forms a first line of defense against environmental triggers, and through secretion of epithelial cytokines, such as IL-33, presents a critical innate response mechanism to injurious insults by initiating type 2 cytokine responses. We recently demonstrated that airway epithelial IL-33 secretion depends on activation of the NADPH Oxidase Dual Oxidase 1 (DUOX1) and redox-dependent activation of the epidermal growth factor receptor (EGFR) and Src kinases. Curiously, activation of type 2 responses by direct airway administration of IL-33 was markedly diminished in DUOX1-deficient mice, suggesting DUOX1 is activated by IL-33 and participates in its downstream signaling. Furthermore, activation of epithelial IL-33 secretion in response to injury or allergens was dramatically attenuated by blockade or siRNA-mediated deletion of the IL-33 receptor (IL-33R/ST2), suggesting that epithelial IL-33 evokes a positive autocrine or paracrine feedback mechanism in which it regulates its own secretion through IL-33R/ST2-mediated signaling. Studies with human bronchial epithelial cells (H292) and primary mouse tracheal epithelial cells (MTEC) showed that IL-33 can directly trigger EGFR and Src activation and type 2 cytokine secretion, via intermediate activation of DUOX1. The activation of these kinases was shown to be associated with increased levels of DUOX1-dependent sulfenylation. Additionally, IL-33 stimulation resulted in ST2-mediated calcium-dependent extracellular secretion of ATP, a known damage signal capable of activating DUOX1. Consistent with its activation by IL-33, inhibition of Src with AZD0530 or siRNA-mediated deletion of Src led to decreased secretion of type 2 cytokines, confirming that Src plays a role in these downstream processes. Overall, our findings suggest that the role of DUOX1 in allergen-induced IL-33 secretion, and activation of type 2 responses, is largely mediated by its involvement in IL-33-dependent signaling and subsequent oxidation and activation of Src and EGFR.
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The transient receptor potential vanilloid 1 (TRPV1) channel is a critical factor in allergen-induced innate immune responses in the airway epithelium
Free Radical Biology and Medicine, 2018Co-Authors: Caspar Schiffers, Aida Habibovic, Milena Hristova, Christopher M. Dustin, Emiel F.m. Wouters, Niki L. Reynaert, Albert Van Der VlietAbstract:The airway epithelium plays a critical role in innate responses to asthma-relevant protease allergens, such as house dust mite (HDM) or Alternaria alternata (ALT), by rapid secretion of IL-1 family alarmins, such as interleukin (IL)-1α and IL-33, that orchestrate appropriate type 2 immune responses. Previous studies indicate that allergen-induced IL-33 secretion is mediated by protease-activated receptors (PAR2) and type 2 purinergic receptors (P2RY2), which induce Ca2+-dependent signaling and activation of the NADPH Oxidase Dual Oxidase 1 (DUOX1). Transient receptor potential (TRP) Ca2+ channels such as TRP Vanilloid 1 (TRPV1) are important in e.g. pain responses, often in coordination with PAR2 and P2YR2 activation, and TRPV1 has recently been implicated in asthma pathology. Using a panel of pharmacological inhibitors and activators of P2YR2, PAR2, and TRPV1, we observed that each of these receptors can provoke activation of DUOX1 and secretion of IL-33 in primary human nasal epithelial (HNE) cells. Further mechanistic studies using primary mouse tracheal epithelial cells (MTECs) or human bronchial epithelial cells (HBE1) confirmed these findings, and showed that TRPV1 contributes importantly to innate responses to HDM and ALT, and the danger signal ATP which activates P2YR2, as shown by activation of DUOX1-dependent H2O2 production, activation of epidermal growth factor receptor signaling, and rapid secretion of IL-33, which were prevented using TRPV1 antagonists or TRPV1-siRNA. Strikingly, inhibition or siRNA silencing of P2YR2 also prevented innate responses to the TRPV1 activator capsaicin, highlighting a close functional relationship of these airway epithelial surface receptors in the innate allergen responses. Finally, airway IL-33 secretion and subsequent type 2 cytokine production in mice in response to acute airway HDM challenge were markedly impaired in TRPV1-deficient mice. Overall, our studies indicate a complex relationship between various receptor types in epithelial responses to environmental triggers, and highlight the importance of TRPV1 in such epithelial responses.
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Progressive loss of Dual Oxidase 1 (DUOX1) contributes to impaired airway epithelial wound responses in the aging lung
Free Radical Biology and Medicine, 2017Co-Authors: Caspar Schiffers, Aida Habibovic, Milena Hristova, Lennart K A Lundblad, Christopher M. Dustin, Albert Van Der VlietAbstract:Age-related chronic diseases, including chronic respiratory diseases such as COPD, are associated with organ function decline, impaired regenerative capacity, and immuno-senescence. Our recent studies indicate that such reparative processes in the lung are mediated by innate epithelial injury responses and production of reactive oxygen species (ROS) by the NADPH Oxidase Dual Oxidase 1 (DUOX1), which were found to be associated with oxidation and activation of epithelial tyrosine kinases, such as epidermal growth factor receptor (EGFR) and the non-receptor tyrosine kinase Src, and also with epithelial secretion of alarmins such as IL-33, which promote epithelial regeneration by activating type 2 immune responses. Contrasting the common belief that aging is associated with increased ROS production, we observed that DUOX1 expression in mouse lungs markedly decreases with age. Moreover, we noticed that DUOX1-deficient mice display accelerated age-related decline in lung function and features of emphysema, as shown by airspace enlargement and increased lung compliance. We hypothesized that loss of DUOX1 may contribute to other features of lung aging, but aged-related lung changes such as increased parenchymal collagen deposition, molecular indices of senescence, or tissue levels of pro-inflammatory cytokines, were all largely unaltered in DUOX1-deficient mice. However, we observed that aged mice display markedly attenuated innate airway responses to inhaled allergens, as illustrated by diminished secretion of IL-33 and other related cytokines. Similar findings were observed in vitro using cultured mouse tracheal epithelial cells (MTEC), in which MTECs from older mice showed dramatically reduced innate responses to injury, which was associated with reduced oxidation and activation of Src and EGFR. Consistent with a potential age-related suppression of DUOX1 by epigenetic mechanisms such as promoter hypermethylation, allergen-induced IL-33 secretion in MTECs from aged mice could be rescued by treatment with the DNA methyltransferase inhibitor AzdC. Overall, these results underline the importance of DUOX1 in airway host defense and regenerative capacity, and indicate that age-related loss of DUOX1 contributes to accelerated impairment of epithelial regenerative capacity and air-space enlargement.
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Airway Epithelial IL-33 Secretion and Feedback Signaling is Associated with Redox Activation of Src Kinase
Free Radical Biology and Medicine, 2017Co-Authors: Christopher M. Dustin, Aida Habibovic, Milena Hristova, David E Heppner, Caspar Schiffers, Albert Van Der VlietAbstract:The airway epithelium forms the primary defense against inhaled allergens and environmental insults to the respiratory system. Aside from acting as a physical barrier, the epithelium also signals for reparative and inflammatory responses by generating various epithelial-derived cytokines and mediators. Chief among these is the epithelial secretion of the alarmin cytokine IL-33, which in turn induces type 2 immune responses. Although these processes serve a protective mechanism by promoting epithelial regenerative pathways, chronic activation of such type 2 responses contribute to chronic respiratory diseases such as asthma and COPD. We recently demonstrated that epithelial IL-33 secretion in response to various injurious triggers is dependent on H2O2 production by the NADPH Oxidase Dual Oxidase 1 (DUOX1), and that this was associated with activation and oxidation of the non-receptor tyrosine kinase Src. However, the precise role of Src in these responses is still unclear, and we hypothesized that redox-dependent activation of Src is critical for increased IL-33 secretion and downstream type 2 responses to allergens. Pretreatment of mice with the Src family kinase inhibitor AZD0530 was found to significantly attenuate epithelial Src activation, as well as expression and secretion of IL-33 and the downstream type 2 cytokines IL-5 and IL-13, in response to acute challenge with house dust mite (HDM). Similar findings were obtained using isolated mouse tracheal epithelial cells (MTEC), in which siRNA-dependent silencing of Src resulted in diminished HDM-induced production of IL-33, as well as IL-5 and IL-13. Interestingly, we noted that HDM-induced IL-33 secretion is diminished upon blockade of the IL-33 receptor ST2, suggesting that IL-33 regulates its own secretion through a positive feedback mechanism. Indeed, induction of type 2 cytokine secretion (IL-13) in airway epithelial cells by direct stimulation with IL-33 was found to be DUOX1-dependent, and associated with increased H2O2 production and activation/oxidation of Src. Building on our recent findings that DUOX1-dependent activation of Src involves oxidation of its C185 and C277 residues, preliminary studies using H292 lung epithelial cells transfected with C185A or C277A Src variants indicate that expression of these variants leads to suppressed HDM-induced IL-33 secretion. Overall, our studies identify Src as a critical mediator of allergen-induced IL-33 secretion and innate type 2 immune responses, and highlight the importance of various redox-sensitive Cys residues in these responses.
