bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular Mechanisms of Cytokine and Chemokine Release from Eosinophils Activated by IL-17A, IL-17F, and IL-23: Implication for Th17 Lymphocytes-Mediated Allergic Inflammation
Authors: Cheung Phyllis F. Y. , Wong Chun K. , Lam Christopher W. K. 
Published: April 2014

Abstract
IL-17A and IL-17F are members of the IL-17 family that play crucial roles in allergic inflammation. Recent studies reported that IL-17A and IL-17F production from a distinct Th lymphocyte subset, Th17, was specifically induced by IL-23, which was produced by dendritic cells and macrophages in response to microbial stimuli. The IL-23-IL-17 axis might therefore provide a link between infections and allergic diseases. In the present study, we investigated the effects of IL-17A, IL-17F, and IL-23, alone or in combination, on cytokine and chemokine release from eosinophils and the underlying intracellular mechanisms. Human eosinophils were found to constitutively express receptors for IL-17A, IL-17F, and IL-23 at the protein level. IL-17A, IL-17F, and IL-23 could induce the release of chemokines GRO-α/CXCL1, IL-8/CXCL8, and MIP-1β/CCL4 from eosinophils, while IL-17F and IL-23 could also increase the production of proinflammatory cytokines IL-1β and IL-6. Synergistic effects were observed in the combined treatment of IL-17F and IL-23 on the release of proinflammatory cytokines, and the effects were dose-dependently enhanced by IL-23, but not IL-17F. Further investigations showed that IL-17A, IL-17F, and IL-23 differentially activated the ERK, p38 MAPK, and NF-κB pathways. Moreover, inhibition of these pathways using selective inhibitors could significantly abolish the chemokine release induced by IL-17A, IL-17F, and IL-23 and the synergistic increases on IL-1β and IL-6 production mediated by combined treatment of IL-17F and IL-23. Taken together, our findings provide insight for the Th17 lymphocyte-mediated activation of eosinophils via differential intracellular signaling cascades in allergic inflammation.
Kruppel-Like Factor 4 Is Essential for Inflammatory Monocyte Differentiation In Vivo
Authors: Alder Jonathan K. , Georgantas Robert W. , Hildreth Richard L. , Kaplan Ian M. , Morisot Sebastien , Yu Xiaobing , McDevitt Michael , Civin Curt I. 
Published: April 2014

Abstract
Several members of the Kruppel-like factor (KLF) family of transcription factors play important roles in differentiation, survival, and trafficking of blood and immune cell types. We demonstrate in this study that hematopoietic cells from KLF4−/− fetal livers (FL) contained normal numbers of functional hematopoietic progenitor cells, were radioprotective, and performed as well as KLF4+/+ cells in competitive repopulation assays. However, hematopoietic “KLF4−/− chimeras” generated by transplantation of KLF4−/− fetal livers cells into lethally irradiated wild-type mice completely lacked circulating inflammatory (CD115+Gr1+) monocytes, and had reduced numbers of resident (CD115+Gr1−) monocytes. Although the numbers and function of peritoneal macrophages were normal in KLF4−/− chimeras, bone marrow monocytic cells from KLF4−/− chimeras expressed lower levels of key trafficking molecules and were more apoptotic. Thus, our in vivo loss-of-function studies demonstrate that KLF4, previously shown to mediate proinflammatory signaling in human macrophages in vitro, is essential for differentiation of mouse inflammatory monocytes, and is involved in the differentiation of resident monocytes. In addition, inducible expression of KLF4 in the HL60 human acute myeloid leukemia cell line stimulated monocytic differentiation and enhanced 12-O-tetradecanoylphorbol 13-acetate induced macrophage differentiation, but blocked all-trans-retinoic acid induced granulocytic differentiation of HL60 cells. The inflammation-selective effects of loss-of-KLF4 and the gain-of-KLF4-induced monocytic differentiation in HL60 cells identify KLF4 as a key regulator of monocytic differentiation and a potential target for translational immune modulation.
Mechanism of IL-1β-Induced Increase in Intestinal Epithelial Tight Junction Permeability
Authors: Al-Sadi Rana , Ye Dongmei , Dokladny Karol , Ma Thomas Y. 
Published: April 2014

Abstract
The IL-1β-induced increase in intestinal epithelial tight junction (TJ) permeability has been postulated to be an important mechanism contributing to intestinal inflammation of Crohn’s disease and other inflammatory conditions of the gut. The intracellular and molecular mechanisms that mediate the IL-1β-induced increase in intestinal TJ permeability remain unclear. The purpose of this study was to elucidate the mechanisms that mediate the IL-1β-induced increase in intestinal TJ permeability. Specifically, the role of myosin L chain kinase (MLCK) was investigated. IL-1β caused a progressive increase in MLCK protein expression. The time course of IL-1β-induced increase in MLCK level correlated linearly with increase in Caco-2 TJ permeability. Inhibition of the IL-1β-induced increase in MLCK protein expression prevented the increase in Caco-2 TJ permeability. Inhibition of the IL-1β-induced increase in MLCK activity also prevented the increase in Caco-2 TJ permeability. Additionally, knock-down of MLCK protein expression by small interference RNA prevented the IL-1β-induced increase in Caco-2 TJ permeability. The IL-1β-induced increase in MLCK protein expression was preceded by an increase in MLCK mRNA expression. The IL-1β-induced increase in MLCK mRNA transcription and subsequent increase in MLCK protein expression and Caco-2 TJ permeability was mediated by activation of NF-κB. In conclusion, our data indicate that the IL-1β increase in Caco-2 TJ permeability was mediated by an increase in MLCK expression and activity. Our findings also indicate that the IL-1β-induced increase in MLCK protein expression and Caco-2 TJ permeability was mediated by an NF-κB-dependent increase in MLCK gene transcription.
Rapid Changes in MicroRNA-146a Expression Negatively Regulate the IL-1β-Induced Inflammatory Response in Human Lung Alveolar Epithelial Cells
Authors: Perry Mark M. , Moschos Sterghios A. , Williams Andrew E. , Shepherd Neil J. , Larner-Svensson Hanna M. , Lindsay Mark A. 
Published: April 2014

Abstract
Posttranscriptional regulation of gene expression by microRNAs (miRNAs) has been implicated in the regulation of chronic physiological and pathological responses. In this report, we demonstrate that changes in the expression of miRNAs can also regulate acute inflammatory responses in human lung alveolar epithelial cells. Thus, stimulation with IL-1β results in a rapid time- and concentration-dependent increase in miRNA-146a and, to a lesser extent, miRNA-146b expression, although these increases were only observed at high IL-1β concentration. Examination of miRNA function by overexpression and inhibition showed that increased miRNA-146a expression negatively regulated the release of the proinflammatory chemokines IL-8 and RANTES. Subsequent examination of the mechanism demonstrated that the action of miRNA-146a was mediated at the translational level and not through the down-regulation of proteins involved in the IL-1β signaling pathway or chemokine transcription or secretion. Overall, these studies indicate that rapid increase in miRNA-146a expression provides a novel mechanism for the negative regulation of severe inflammation during the innate immune response.
Depletion of β-Arrestin-2 Promotes Tumor Growth and Angiogenesis in a Murine Model of Lung Cancer
Authors: Raghuwanshi Sandeep K. , Nasser Mohd W. , Chen Xiaoxin , Strieter Robert M. , Richardson Ricardo M. 
Published: April 2014

Abstract
Arrestins are adaptor/scaffold proteins that complex with activated and phosphorylated G protein-coupled receptor to terminate G protein activation and signal transduction. These complexes also mediate downstream signaling, independently of G protein activation. We have previously shown that β-arrestin-2 (βarr2) depletion promotes CXCR2-mediated cellular signaling, including angiogenesis and excisional wound closure. This study was designed to investigate the role of βarr2 in tumorigenesis using a murine model of lung cancer. To that end, heterotopic murine Lewis lung cancer and tail vein metastasis tumor model systems in βarr2-deficient mice (βarr2−/−) and control littermates (βarr2+/+) were used. βarr2−/− mice exhibited a significant increase in Lewis lung cancer tumor growth and metastasis relative to βarr2+/+ mice. This correlated with decreased number of tumor-infiltrating lymphocytes but with elevated levels of the ELR+ chemokines (CXCL1/keratinocyte-derived chemokine and CXCL2/MIP-2), vascular endothelial growth factor, and microvessel density. NF-κB activity was also enhanced in βarr2−/− mice, whereas hypoxia-inducible factor-1α expression was decreased. Inhibition of CXCR2 or NF-κB reduced tumor growth in both βarr2−/− and βarr2+/+ mice. NF-κB inhibition also decreased ELR+ chemokines and vascular endothelial growth factor expression. Altogether, the data suggest that βarr2 modulates tumorigenesis by regulating inflammation and angiogenesis through activation of CXCR2 and NF-κB.
Programmed Death (PD)-1:PD-Ligand 1/PD-Ligand 2 Pathway Inhibits T Cell Effector Functions during Human Tuberculosis
Authors: Jurado Javier O. , Alvarez Ivana B. , Pasquinelli Virginia , Martínez Gustavo J. , Quiroga María F. , Abbate Eduardo , Musella Rosa M. , Chuluyan H. Eduardo , García Verónica E. 
Published: April 2014

Abstract
Protective immunity against Mycobacterium tuberculosis requires the generation of cell-mediated immunity. We investigated the expression and role of programmed death 1 (PD-1) and its ligands, molecules known to modulate T cell activation, in the regulation of IFN-γ production and lytic degranulation during human tuberculosis. We demonstrated that specific Ag-stimulation increased CD3+PD-1+ lymphocytes in peripheral blood and pleural fluid from tuberculosis patients in direct correlation with IFN-γ production from these individuals. Moreover, M. tuberculosis-induced IFN-γ participated in the up-regulation of PD-1 expression. Blockage of PD-1 or PD-1 and its ligands (PD-Ls: PD-L1, PD-L2) enhanced the specific degranulation of CD8+ T cells and the percentage of specific IFN-γ-producing lymphocytes against the pathogen, demonstrating that the PD-1:PD-Ls pathway inhibits T cell effector functions during active M. tuberculosis infection. Furthermore, the simultaneous blockage of the inhibitory receptor PD-1 together with the activation of the costimulatory protein signaling lymphocytic activation molecule led to the promotion of protective IFN-γ responses to M. tuberculosis, even in patients with weak cell-mediated immunity against the bacteria. Together, we demonstrated that PD-1 interferes with T cell effector functions against M. tuberculosis, suggesting that PD-1 has a key regulatory role during the immune response of the host to the pathogen.
Retrogenic Modeling of Experimental Allergic Encephalomyelitis Associates T Cell Frequency but Not TCR Functional Affinity with Pathogenicity
Authors: Alli Rajshekhar , Nguyen Phuong , Geiger Terrence L. 
Published: April 2014

Abstract
The properties of a self-specific T cell’s TCR that determine its pathogenicity are not well understood. We developed TCR retroviral transgenic, or retrogenic, models of myelin oligodendroglial glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) to compare the pathologic potential of five H-2 Ab/MOG35–55-specific TCRs. The TCRs were cloned and retrovirally transduced into either TCRαβ-deficient hybridoma cells or Rag1−/− bone marrow progenitor cells. Comparison of the hybridomas, identical except for TCR sequence, revealed distinct responsiveness, or functionally determined affinity, for cognate Ag. Retrogenic mice were produced by transfer of transduced progenitor cells into Rag1−/− recipients. T cells were detected within 4 wk. Engraftment levels varied considerably among the different TCRs and showed separate variability among individual mice. T cells were predominantly naive and virtually exclusively CD4+ and CD25−. Relative responses of the retrogenic T cells to Ag paralleled those of the hybridoma cells. Induction of EAE through active immunization led to rapid and severe disease in all mice expressing MOG-specific TCR. The mice additionally developed spontaneous disease, the incidence of which varied with the individual receptors. Interestingly, spontaneous disease frequency and intensity could not be correlated with the functional affinity of the respective TCR. Instead, it was associated with engraftment level, even when measured weeks before the onset of disease symptoms. Our results demonstrate the feasibility of using retrogenic modeling to compare TCRs in the EAE system. They further suggest that affinity is not a primary determinant in spontaneous EAE development in mice expressing monotypic TCRs and that autoreactive T cell frequency is of greater significance.
Defective MHC Class II Presentation by Dendritic Cells Limits CD4 T Cell Help for Antitumor CD8 T Cell Responses
Authors: Gerner Michael Y. , Casey Kerry A. , Mescher Matthew F. 
Published: April 2014

Abstract
Cancer immunosurveillance failure is largely attributed to insufficient activation signals and dominant inhibitory stimuli for tumor Ag (TAg)-specific CD8 T cells. CD4 T cells have been shown to license dendritic cells (DC), thereby having the potential for converting CD8 T cell responses from tolerance to activation. To understand the potential cooperation of TAg-specific CD4 and CD8 T cells, we have characterized the responses of naive TCR transgenic CD8 and CD4 T cells to poorly immunogenic murine tumors. We found that whereas CD8 T cells sensed TAg and were tolerized, the CD4 T cells remained ignorant throughout tumor growth and did not provide help. This disparity in responses was due to normal TAg MHC class I cross-presentation by immature CD8α+ DC in the draining lymph node, but poor MHC class II presentation on all DC subsets due to selective inhibition by the tumor microenvironment. Thus, these results reveal a novel mechanism of cancer immunosubversion, in which inhibition of MHC-II TAg presentation on DC prevents CD4 T cell priming, thereby blocking any potential for licensing CD8α+ DC and helping tolerized CD8 T cells.
Alloreactive CD8 T Cell Tolerance Requires Recipient B Cells, Dendritic Cells, and MHC Class II
Authors: Fehr Thomas , Haspot Fabienne , Mollov Joshua , Chittenden Meredith , Hogan Timothy , Sykes Megan 
Published: April 2014

Abstract
Allogeneic bone marrow chimerism induces robust systemic tolerance to donor alloantigens. Achievement of chimerism requires avoidance of marrow rejection by pre-existing CD4 and CD8 T cells, either of which can reject fully MHC-mismatched marrow. Both barriers are overcome with a minimal regimen involving anti-CD154 and low dose (3 Gy) total body irradiation, allowing achievement of mixed chimerism and tolerance in mice. CD4 cells are required to prevent marrow rejection by CD8 cells via a novel pathway, wherein recipient CD4 cells interacting with recipient class II MHC tolerize directly alloreactive CD8 cells. We demonstrate a critical role for recipient MHC class II, B cells, and dendritic cells in a pathway culminating in deletional tolerance of peripheral alloreactive CD8 cells.
Cutting Edge: Inflammasome Activation by Alum and Alum’s Adjuvant Effect Are Mediated by NLRP3
Authors: Li Hanfen , Willingham Stephen B. , Ting Jenny P.-Y. , Re Fabio 
Published: April 2014

AbstractAlum is the only adjuvant approved for routine use in humans, although the basis for its adjuvanticity remains poorly understood. We have recently shown that alum activates caspase-1 and induces secretion of mature IL-1β and IL-18. In this study we show that, in human and mouse macrophages, alum-induced secretion of IL-1β, IL-18, and IL-33 is mediated by the NLR (nucleotide-binding domain leucine-rich repeat-containing) protein NLRP3 and its adaptor ASC, but not by NLRC4. Other particulate adjuvants, such as QuilA and chitosan, induce inflammasome activation in a NLRP3-dependent fashion, suggesting that activation of the NLRP3-inflammasome may be a common mechanism of action of particulate adjuvants. Importantly, we demonstrate that Ag-specific Ab production elicited by vaccines that contain alum is significantly impaired in NLRP3-deficient mice. Our results demonstrate for the first time a role for the NLRP3-inflammasome during development of the immune response elicited by alum-enhanced vaccination and suggest that therapeutic intervention aimed at NLRP3 may improve adjuvant efficacy.
B Cell Chemoattractant CXCL13 Is Preferentially Expressed by Human Th17 Cell Clones
Authors: Takagi Rie , Higashi Takehiro , Hashimoto Kumiko , Nakano Kazuhisa , Mizuno Yosuke , Okazaki Yasushi , Matsushita Sho 
Published: April 2014

Abstract
Th 17 cells represent a novel subset of CD4+ T cells that have a protective effect against extracellular microbes, while they are also responsible for autoimmune disorders in mice. However, the protein expression profile of Th17 cells remains to be clarified. In this study, we report an effective method to establish human allo-reactive Th17 cell clones and demonstrate that human Th17, but not Th1 or Th2, cells express B cell chemoattractant CXCL13, by using DNA chips, RT-PCR, and ELISA. Such a pattern was also the case in Candida albicans-specific Th17 clones and synovial fluid specimens obtained from patients with rheumatoid arthritis. The biological implication of this finding is discussed.
Lipopolysaccharides from Bordetella pertussis and Bordetella parapertussis Differently Modulate Human Dendritic Cell Functions Resulting in Divergent Prevalence of Th17-Polarized Responses
Authors: Fedele Giorgio , Nasso Maria , Spensieri Fabiana , Palazzo Raffaella , Frasca Loredana , Watanabe Mineo , Ausiello Clara M. 
Published: April 2014

Abstract
Bordetella pertussis and B. parapertussis are the etiological agents of pertussis, yet the former has a higher incidence and is the cause of a more severe disease, in part due to pertussis toxin. To identify other factors contributing to the different pathogenicity of the two species, we analyzed the capacity of structurally different lipooligosaccharide (LOS) from B. pertussis and LPS from B. parapertussis to influence immune functions regulated by dendritic cells. Either B. pertussis LOS and B. parapertussis LPS triggered TLR4 signaling and induced phenotypic maturation and IL-10, IL-12p40, IL-23, IL-6, and IL-1β production in human monocyte-derived dendritic cells (MDDC). B. parapertussis LPS was a stronger inducer of all these activities as compared with B. pertussis LOS, with the notable exception of IL-1β, which was equally produced. Only B. parapertussis LPS was able to induce IL-27 expression. In addition, although MDDC activation induced by B. parapertussis LPS was greatly dependent on soluble CD14, B. pertussis LOS activity was CD14-independent. The analysis of the intracellular pathways showed that B. parapertussis LPS and B. pertussis LOS equally induced IκBα and p38 MAPK phosphorylation, but B. pertussis LOS triggered ERK1/2 phosphorylation more rapidly and at higher levels than B. parapertussis LPS. Furthermore, B. pertussis LOS was unable to induce MyD88-independent gene induction, which was instead activated by B. parapertussis LPS, witnessed by STAT1 phosphorylation and induction of the IFN-dependent genes, IFN regulatory factor-1 and IFN-inducible protein-10. These differences resulted in a divergent regulation of Th cell responses, B. pertussis LOS MDDC driving a predominant Th17 polarization. Overall, the data observed reflect the different structure of the two LPS and the higher Th17 response induced by B. pertussis LOS may contribute to the severity of pertussis in humans.
cis-Urocanic Acid Initiates Gene Transcription in Primary Human Keratinocytes
Authors: Kaneko Kazuyo , Smetana-Just Ulrike , Matsui Mary , Young Antony R. , John Susan , Norval Mary , Walker Susan L. 
Published: April 2014

Abstract
It is well established that solar UV radiation (UVR) suppresses cutaneous cell-mediated immunity in humans. trans-Urocanic acid (trans-UCA) is a major UVR-absorbing skin molecule that undergoes a photoisomerization to its cis-isomer following UVR exposure. Animal studies have demonstrated that cis-UCA plays a role in UVR-induced immune suppression, but the molecular mechanisms of action of cis-UCA are not fully understood. In this study, we examined changes in gene expression and synthesis of cytokines and PGE2 following UCA treatment of primary human keratinocytes. A limited microarray analysis of keratinocytes from two donors indicated that ∼400 genes were induced by solar-simulated radiation (SSR), 16 of which were also up-regulated by cis-UCA. In contrast, trans-UCA had little or no effect on gene expression. The genes up-regulated by both cis-UCA and SSR were associated with apoptosis, cell growth arrest, cytokines, and oxidative stress. Further studies using primary keratinocytes from four new donors showed that PG-endoperoxide synthase-2 was dramatically induced by cis-UCA, resulting in an enhanced secretion of PGE2 into the cell culture supernatant. cis-UCA also increased cytokine protein production such as that of TNF-α, IL-6, and IL-8 in a dose-dependent manner. SSR had the same effect as cis-UCA, but trans-UCA had no effect. In addition, activation of NF-κB and lipid peroxidation were induced by cis-UCA and SSR, but not trans-UCA, suggesting possible upstream events of the gene expression changes. The data suggest that the induction of immune suppression by cis-UCA may involve the initiation of gene transcription of immunomodulatory mediators in primary human keratinocytes.
A Function for IL-7R for CD4+CD25+Foxp3+ T Regulatory Cells
Authors: Bayer Allison L. , Lee Joon Youb , de la Barrera Anabel , Surh Charles D. , Malek Thomas R. 
Published: April 2014

Abstract
The IL-2/IL-2R interaction is important for development and peripheral homeostasis of T regulatory (Treg) cells. IL-2- and IL-2R-deficient mice are not completely devoid of Foxp3+ cells, but rather lack population of mature CD4+CD25+Foxp3high Treg cells and contain few immature CD4+CD25−Foxp3low T cells. Interestingly, common γ chain (γc) knockout mice have been shown to have a near complete absence of Foxp3+ Treg cells, including the immature CD25−Foxp3low subset. Therefore, other γc-cytokine(s) must be critically important during thymic development of CD4+CD25+Foxp3+ Treg cells apart from the IL-2. The present study was undertaken to determine whether the γc-cytokines IL-7 or IL-15 normally contribute to expression of Foxp3 and Treg cell production. These studies revealed that mice double deficient in IL-2Rβ and IL-7Rα contained a striking lack in the CD4+Foxp3+ population and the Treg cell defect recapitulated the γc knockout mice. In the absence of IL-7R signaling, IL-15/IL-15R interaction is dispensable for the production of CD4+CD25+Foxp3+ Treg cells, indicating that normal thymic Treg cell production likely depends on signaling through both IL-2 and IL-7 receptors. Selective thymic reconstitution of IL-2Rβ in mice double deficient in IL-2Rβ and IL-7Rα established that IL-2Rβ is dominant and sufficient to restore production of Treg cells. Furthermore, the survival of peripheral CD4+Foxp3low cells in IL-2Rβ−/− mice appears to depend upon IL-7R signaling. Collectively, these data indicate that IL-7R signaling contributes to Treg cell development and peripheral homeostasis.