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  1. Article ; Online: IFN-κ is critical for normal wound repair and is decreased in diabetic wounds

    Sonya J. Wolf / Christopher O. Audu / Amrita Joshi / Aaron denDekker / William J. Melvin / Frank M. Davis / Xianying Xing / Rachael Wasikowski / Lam C. Tsoi / Steven L. Kunkel / Johann E. Gudjonsson / Mary X. O’Riordan / J. Michelle Kahlenberg / Katherine A. Gallagher

    JCI Insight, Vol 7, Iss

    2022  Volume 9

    Abstract: Wound repair following acute injury requires a coordinated inflammatory response. Type I IFN signaling is important for regulating the inflammatory response after skin injury. IFN-κ, a type I IFN, has recently been found to drive skin inflammation in ... ...

    Abstract Wound repair following acute injury requires a coordinated inflammatory response. Type I IFN signaling is important for regulating the inflammatory response after skin injury. IFN-κ, a type I IFN, has recently been found to drive skin inflammation in lupus and psoriasis; however, the role of IFN-κ in the context of normal or dysregulated wound healing is unclear. Here, we show that Ifnk expression is upregulated in keratinocytes early after injury and is essential for normal tissue repair. Under diabetic conditions, IFN-κ was decreased in wound keratinocytes, and early inflammation was impaired. Furthermore, we found that the histone methyltransferase mixed-lineage leukemia 1 (MLL1) is upregulated early following injury and regulates Ifnk expression in diabetic wound keratinocytes via an H3K4me3-mediated mechanism. Using a series of in vivo studies with a geneticall y engineered mouse model (Mll1fl/fl K14cre–) and human wound tissues from patients with T2D, we demonstrate that MLL1 controls wound keratinocyte–mediated Ifnk expression and that Mll1 expression is decreased in T2D keratinocytes. Importantly, we found the administration of IFN-κ early following injury improves diabetic tissue repair through increasing early inflammation, collagen deposition, and reepithelialization. These findings have significant implications for understanding the complex role type I IFNs play in keratinocytes in normal and diabetic wound healing. Additionally, they suggest that IFN may be a viable therapeutic target to improve diabetic wound repair.
    Keywords Inflammation ; Medicine ; R
    Subject code 616
    Language English
    Publishing date 2022-05-01T00:00:00Z
    Publisher American Society for Clinical investigation
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Spred2 Deficiency Exacerbates D-Galactosamine/Lipopolysaccharide -induced Acute Liver Injury in Mice via Increased Production of TNFα

    Xu Yang / Masayoshi Fujisawa / Teizo Yoshimura / Toshiaki Ohara / Miwa Sato / Megumi Mino / Thar Htet San / Tong Gao / Steven L. Kunkel / Akihiro Matsukawa

    Scientific Reports, Vol 8, Iss 1, Pp 1-

    2018  Volume 12

    Abstract: Abstract Acute liver injury (ALI) is characterized by hepatocyte damage and inflammation. In the present study, we examined whether the absence of Sprouty-related EVH1-domain-containing protein 2 (Spred2), a negative regulator of the Ras/Raf/ERK/MAPK ... ...

    Abstract Abstract Acute liver injury (ALI) is characterized by hepatocyte damage and inflammation. In the present study, we examined whether the absence of Sprouty-related EVH1-domain-containing protein 2 (Spred2), a negative regulator of the Ras/Raf/ERK/MAPK pathway, influences ALI induced by D-galactosamine (D-GalN) and lipopolysaccharide (LPS). Compared to wild-type mice, Spred2−/− mice developed exacerbated liver injury represented by enhanced hepatocyte damage and inflammation. Enhanced ERK activation was observed in Spred2−/−-livers, and the MEK/ERK inhibitor U0126 ameliorated ALI. Hepatic tumour necrosis factor α (TNFα) and interleukin (IL)-1β levels were increased in Spred-2−/−-livers, and the neutralization of TNFα dramatically ameliorated ALI, which was associated with decreased levels of endogenous TNFα and IL-1β. When mice were challenged with D-GalN and TNFα, much severer ALI was observed in Spred2−/− mice with significant increases in endogenous TNFα and IL-1β in the livers. Immunohistochemically, Kupffer cells were found to produce TNFα, and isolated Kupffer cells from Spred2−/− mice produced significantly higher levels of TNFα than those from wild-type mice after LPS stimulation, which was significantly decreased by U0126. These results suggest that Spred2 negatively regulates D-GalN/LPS-induced ALI under the control of TNFα in Kupffer cells. Spred2 may present a therapeutic target for the treatment of ALI.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2018-01-01T00:00:00Z
    Publisher Nature Publishing Group
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Type I Interferon Induced Epigenetic Regulation of Macrophages Suppresses Innate and Adaptive Immunity in Acute Respiratory Viral Infection.

    Danielle N Kroetz / Ronald M Allen / Matthew A Schaller / Cleyton Cavallaro / Toshihiro Ito / Steven L Kunkel

    PLoS Pathogens, Vol 11, Iss 12, p e

    2015  Volume 1005338

    Abstract: Influenza A virus (IAV) is an airborne pathogen that causes significant morbidity and mortality each year. Macrophages (Mϕ) are the first immune population to encounter IAV virions in the lungs and are required to control infection. In the present study, ...

    Abstract Influenza A virus (IAV) is an airborne pathogen that causes significant morbidity and mortality each year. Macrophages (Mϕ) are the first immune population to encounter IAV virions in the lungs and are required to control infection. In the present study, we explored the mechanism by which cytokine signaling regulates the phenotype and function of Mϕ via epigenetic modification of chromatin. We have found that type I interferon (IFN-I) potently upregulates the lysine methyltransferase Setdb2 in murine and human Mϕ, and in turn Setdb2 regulates Mϕ-mediated immunity in response to IAV. The induction of Setdb2 by IFN-I was significantly impaired upon inhibition of the JAK-STAT signaling cascade, and chromatin immunoprecipitation revealed that both STAT1 and interferon regulatory factor 7 bind upstream of the transcription start site to induce expression. The generation of Setdb2LacZ reporter mice revealed that IAV infection results in systemic upregulation of Setdb2 in myeloid cells. In the lungs, alveolar Mϕ expressed the highest level of Setdb2, with greater than 70% lacZ positive on day 4 post-infection. Silencing Setdb2 activity in Mϕ in vivo enhanced survival in lethal IAV infection. Enhanced host protection correlated with an amplified antiviral response and less obstruction to the airways. By tri-methylating H3K9, Setdb2 silenced the transcription of Mx1 and Isg15, antiviral effectors that inhibit IAV replication. Accordingly, a reduced viral load in knockout mice on day 8 post-infection was linked to elevated Isg15 and Mx1 transcript in the lungs. In addition, Setdb2 suppressed the expression of a large number of other genes with proinflammatory or immunomodulatory function. This included Ccl2, a chemokine that signals through CCR2 to regulate monocyte recruitment to infectious sites. Consistently, knockout mice produced more CCL2 upon IAV infection and this correlated with a 2-fold increase in the number of inflammatory monocytes and alveolar Mϕ in the lungs. Finally, Setdb2 expression by Mϕ suppressed ...
    Keywords Immunologic diseases. Allergy ; RC581-607 ; Biology (General) ; QH301-705.5
    Subject code 570
    Language English
    Publishing date 2015-12-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: RSV-Induced H3K4 Demethylase KDM5B Leads to Regulation of Dendritic Cell-Derived Innate Cytokines and Exacerbates Pathogenesis In Vivo.

    Catherine Ptaschinski / Sumanta Mukherjee / Martin L Moore / Mareike Albert / Kristian Helin / Steven L Kunkel / Nicholas W Lukacs

    PLoS Pathogens, Vol 11, Iss 6, p e

    2015  Volume 1004978

    Abstract: Respiratory syncytial virus (RSV) infection can result in severe disease partially due to its ability to interfere with the initiation of Th1 responses targeting the production of type I interferons (IFN) and promoting a Th2 immune environment. ... ...

    Abstract Respiratory syncytial virus (RSV) infection can result in severe disease partially due to its ability to interfere with the initiation of Th1 responses targeting the production of type I interferons (IFN) and promoting a Th2 immune environment. Epigenetic modulation of gene transcription has been shown to be important in regulating inflammatory pathways. RSV-infected bone marrow-derived DCs (BMDCs) upregulated expression of Kdm5b/Jarid1b H3K4 demethylase. Kdm5b-specific siRNA inhibition in BMDC led to a 10-fold increase in IFN-β as well as increases in IL-6 and TNF-α compared to control-transfected cells. The generation of Kdm5bfl/fl-CD11c-Cre+ mice recapitulated the latter results during in vitro DC activation showing innate cytokine modulation. In vivo, infection of Kdm5bfl/fl-CD11c-Cre+ mice with RSV resulted in higher production of IFN-γ and reduced IL-4 and IL-5 compared to littermate controls, with significantly decreased inflammation, IL-13, and mucus production in the lungs. Sensitization with RSV-infected DCs into the airways of naïve mice led to an exacerbated response when mice were challenged with live RSV infection. When Kdm5b was blocked in DCs with siRNA or DCs from Kdm5bfl/fl-CD11c-CRE mice were used, the exacerbated response was abrogated. Importantly, human monocyte-derived DCs treated with a chemical inhibitor for KDM5B resulted in increased innate cytokine levels as well as elicited decreased Th2 cytokines when co-cultured with RSV reactivated CD4+ T cells. These results suggest that KDM5B acts to repress type I IFN and other innate cytokines to promote an altered immune response following RSV infection that contributes to development of chronic disease.
    Keywords Immunologic diseases. Allergy ; RC581-607 ; Biology (General) ; QH301-705.5
    Subject code 570
    Language English
    Publishing date 2015-06-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Epigenetic regulation of the PGE2 pathway modulates macrophage phenotype in normal and pathologic wound repair

    Frank M. Davis / Lam C. Tsoi / Rachael Wasikowski / Aaron denDekker / Amrita Joshi / Carol Wilke / Hongping Deng / Sonya Wolf / Andrea Obi / Steven Huang / Allison C. Billi / Scott Robinson / Jay Lipinski / William J. Melvin / Christopher O. Audu / Stephan Weidinger / Steven L. Kunkel / Andrew Smith / Johann E. Gudjonsson /
    Bethany B. Moore / Katherine A. Gallagher

    JCI Insight, Vol 5, Iss

    2020  Volume 17

    Abstract: Macrophages are a primary immune cell involved in inflammation, and their cell plasticity allows for transition from an inflammatory to a reparative phenotype and is critical for normal tissue repair following injury. Evidence suggests that epigenetic ... ...

    Abstract Macrophages are a primary immune cell involved in inflammation, and their cell plasticity allows for transition from an inflammatory to a reparative phenotype and is critical for normal tissue repair following injury. Evidence suggests that epigenetic alterations play a critical role in establishing macrophage phenotype and function during normal and pathologic wound repair. Here, we find in human and murine wound macrophages that cyclooxygenase 2/prostaglandin E2 (COX-2/PGE2) is elevated in diabetes and regulates downstream macrophage-mediated inflammation and host defense. Using single-cell RNA sequencing of human wound tissue, we identify increased NF-κB–mediated inflammation in diabetic wounds and show increased COX-2/PGE2 in diabetic macrophages. Further, we identify that COX-2/PGE2 production in wound macrophages requires epigenetic regulation of 2 key enzymes in the cytosolic phospholipase A2/COX-2/PGE2 (cPLA2/COX-2/PGE2) pathway. We demonstrate that TGF-β–induced miRNA29b increases COX-2/PGE2 production via inhibition of DNA methyltransferase 3b–mediated hypermethylation of the Cox-2 promoter. Further, we find mixed-lineage leukemia 1 (MLL1) upregulates cPLA2 expression and drives COX-2/PGE2. Inhibition of the COX-2/PGE2 pathway genetically (Cox2fl/fl Lyz2Cre+) or with a macrophage-specific nanotherapy targeting COX-2 in tissue macrophages reverses the inflammatory macrophage phenotype and improves diabetic tissue repair. Our results indicate the epigenetically regulated PGE2 pathway controls wound macrophage function, and cell-targeted manipulation of this pathway is feasible to improve diabetic wound repair.
    Keywords Endocrinology ; Inflammation ; Medicine ; R
    Subject code 616
    Language English
    Publishing date 2020-09-01T00:00:00Z
    Publisher American Society for Clinical investigation
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: CCR4 Controls the Suppressive Effects of Regulatory T Cells on Early and Late Events during Severe Sepsis.

    Raphael Molinaro / Cyntia Pecli / Rafael F Guilherme / José Carlos Alves-Filho / Fernando Q Cunha / Claudio Canetti / Steven L Kunkel / Marcelo T Bozza / Claudia F Benjamim

    PLoS ONE, Vol 10, Iss 7, p e

    2015  Volume 0133227

    Abstract: Sepsis is a deadly disease characterized by an overwhelming release of inflammatory mediators and the activation of different types of cells. This altered state of cell activation, termed leukocyte reprogramming, contributes to patient outcome. However, ... ...

    Abstract Sepsis is a deadly disease characterized by an overwhelming release of inflammatory mediators and the activation of different types of cells. This altered state of cell activation, termed leukocyte reprogramming, contributes to patient outcome. However, the understanding of the process underlying sepsis and the role of regulatory T cells (Tregs) in sepsis remains to be elucidated. In this study, we investigated the role of CCR4, the CCL17/CCL22 chemokine receptor, in the innate and acquired immune responses during severe sepsis and the role of Tregs in effecting the outcome. In contrast with wild-type (WT) mice subjected to cecal ligation and puncture (CLP) sepsis, CCR4-deficient (CCR4-/-) septic mice presented an increased survival rate, significant neutrophil migration toward the infection site, a low bacterial count in the peritoneum, and reduced lung inflammation and serum cytokine levels. Thus, a better early host response may favor an adequate long-term response. Consequently, the CCR4-/- septic mice were not susceptible to secondary fungal infection, in contrast with the WT septic mice. Furthermore, Tregs cells from the CCR4-/- septic mice showed reduced suppressive effects on neutrophil migration (both in vivo and in vitro), lymphocyte proliferation and ROS production from activated neutrophils, in contrast with what was observed for Tregs from the WT septic mice. These data show that CCR4 is involved in immunosuppression after severe sepsis and suggest that CCR4+ Tregs negatively modulate the short and long-term immune responses.
    Keywords Medicine ; R ; Science ; Q
    Subject code 616
    Language English
    Publishing date 2015-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Dysregulated cytokine expression by CD4+ T cells from post-septic mice modulates both Th1 and Th2-mediated granulomatous lung inflammation.

    William F Carson / Toshihiro Ito / Matthew Schaller / Karen A Cavassani / Stephen W Chensue / Steven L Kunkel

    PLoS ONE, Vol 6, Iss 5, p e

    2011  Volume 20385

    Abstract: Previous epidemiological studies in humans and experimental studies in animals indicate that survivors of severe sepsis exhibit deficiencies in the activation and effector function of immune cells. In particular, CD4+ T lymphocytes can exhibit reduced ... ...

    Abstract Previous epidemiological studies in humans and experimental studies in animals indicate that survivors of severe sepsis exhibit deficiencies in the activation and effector function of immune cells. In particular, CD4+ T lymphocytes can exhibit reduced proliferative capacity and improper cytokine responses following sepsis. To further investigate the cell-intrinsic defects of CD4+ T cells following sepsis, splenic CD4+ T cells from sham surgery and post-septic mice were transferred into lymphopenic mice. These recipient mice were then subjected to both TH1-(purified protein derivative) and TH2-(Schistosoma mansoni egg antigen) driven models of granulomatous lung inflammation. Post-septic CD4+ T cells mediated smaller TH1 and larger TH2 lung granulomas as compared to mice receiving CD4+ T cells from sham surgery donors. However, cytokine production by lymph node cells in antigen restimulation assays indicated increased pan-specific cytokine expression by post-septic CD4+ T cell recipient mice in both TH1 and TH2 granuloma models. These include increased production of T(H)2 cytokines in TH1 inflammation, and increased production of T(H)1 cytokines in TH2 inflammation. These results suggest that cell-intrinsic defects in CD4+ T cell effector function can have deleterious effects on inflammatory processes post-sepsis, due to a defect in the proper regulation of TH-specific cytokine expression.
    Keywords Medicine ; R ; Science ; Q
    Subject code 570
    Language English
    Publishing date 2011-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: IRAK-M regulates chromatin remodeling in lung macrophages during experimental sepsis.

    Kenneth Lyn-Kew / Eric Rich / Xianying Zeng / Haitao Wen / Steven L Kunkel / Michael W Newstead / Urvashi Bhan / Theodore J Standiford

    PLoS ONE, Vol 5, Iss 6, p e

    2010  Volume 11145

    Abstract: Sepsis results in a profound state of immunosuppression, which is temporally associated with impaired leukocyte function. The mechanism of leukocyte reprogramming in sepsis is incompletely understood. In this study, we explored mechanisms contributing to ...

    Abstract Sepsis results in a profound state of immunosuppression, which is temporally associated with impaired leukocyte function. The mechanism of leukocyte reprogramming in sepsis is incompletely understood. In this study, we explored mechanisms contributing to dysregulated inflammatory cytokine expression by pulmonary macrophages during experimental sepsis. Pulmonary macrophages (PM) recovered from the lungs of mice undergoing cecal ligation and puncture (CLP) display transiently reduced expression of some, but not all innate genes in response to LPS. Impaired expression of TNF-alpha and iNOS was associated with reduced acetylation and methylation of specific histones (AcH4 and H3K4me3) and reduced binding of RNA polymerase II to the promoters of these genes. Transient impairment in LPS-induced cytokine responses in septic PM temporally correlated with induction of IRAK-M mRNA and protein, which occurred in a MyD88-dependent fashion. PM isolated from IRAK-M(-/-) mice were largely refractory to CLP-induced impairment in cytokine expression, chromatin remodeling, recruitment of RNA polymerase II, and induction of histone deacetylase-2 observed during sepsis. Our findings indicate that systemic sepsis induces epigenetic silencing of cytokine gene expression in lung macrophages, and IRAK-M appears to be a critical mediator of this response.
    Keywords Medicine ; R ; Science ; Q
    Subject code 610
    Language English
    Publishing date 2010-06-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Identification of key processes that control tumor necrosis factor availability in a tuberculosis granuloma.

    Mohammad Fallahi-Sichani / Matthew A Schaller / Denise E Kirschner / Steven L Kunkel / Jennifer J Linderman

    PLoS Computational Biology, Vol 6, Iss 5, p e

    2010  Volume 1000778

    Abstract: Tuberculosis (TB) granulomas are organized collections of immune cells comprised of macrophages, lymphocytes and other cells that form in the lung as a result of immune response to Mycobacterium tuberculosis (Mtb) infection. Formation and maintenance of ... ...

    Abstract Tuberculosis (TB) granulomas are organized collections of immune cells comprised of macrophages, lymphocytes and other cells that form in the lung as a result of immune response to Mycobacterium tuberculosis (Mtb) infection. Formation and maintenance of granulomas are essential for control of Mtb infection and are regulated in part by a pro-inflammatory cytokine, tumor necrosis factor-alpha (TNF). To characterize mechanisms that control TNF availability within a TB granuloma, we developed a multi-scale two compartment partial differential equation model that describes a granuloma as a collection of immune cells forming concentric layers and includes TNF/TNF receptor binding and trafficking processes. We used the results of sensitivity analysis as a tool to identify experiments to measure critical model parameters in an artificial experimental model of a TB granuloma induced in the lungs of mice following injection of mycobacterial antigen-coated beads. Using our model, we then demonstrated that the organization of immune cells within a TB granuloma as well as TNF/TNF receptor binding and intracellular trafficking are two important factors that control TNF availability and may spatially coordinate TNF-induced immunological functions within a granuloma. Further, we showed that the neutralization power of TNF-neutralizing drugs depends on their TNF binding characteristics, including TNF binding kinetics, ability to bind to membrane-bound TNF and TNF binding stoichiometry. To further elucidate the role of TNF in the process of granuloma development, our modeling and experimental findings on TNF-associated molecular scale aspects of the granuloma can be incorporated into larger scale models describing the immune response to TB infection. Ultimately, these modeling and experimental results can help identify new strategies for TB disease control/therapy.
    Keywords Biology (General) ; QH301-705.5
    Subject code 570
    Language English
    Publishing date 2010-05-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Role of CC chemokine CCL6/C10 as a monocyte chemoattractant in a murine acute peritonitis

    Akihiro Matsukawa / Steven L. Kunkel / Andrew M. LaFleur / Nicholas W. Lukacs

    Mediators of Inflammation, Vol 13, Iss 5-6, Pp 349-

    2004  Volume 355

    Keywords Acute inflammation ; CC chemokines ; Eosinophils ; Monocytes/macrophages ; Neutrophils. ; Pathology ; RB1-214 ; Medicine ; R ; DOAJ:Pathology ; DOAJ:Medicine (General) ; DOAJ:Health Sciences
    Language English
    Publishing date 2004-01-01T00:00:00Z
    Publisher Hindawi Publishing Corporation
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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