bluuebunny/crossref_metadata_2025_split huggingface dataset:
p38 Mitogen-Activated Protein Kinase and c-Jun-NH2-Terminal Kinase Regulate RANTES Production by Influenza Virus-Infected Human Bronchial Epithelial Cells
Authors: Kujime Kousei , Hashimoto Shu , Gon Yasuhiro , Shimizu Kazufumi , Horie Takashi 
Published: April 2014

Abstract
Airway epithelial cells which are the initial site of influenza virus (IV) infection are suggested to participate in airway inflammatory response by expressing various cytokines including RANTES; however, the intracellular signal that regulates RANTES expression has not been determined. In the present study, we examined the role of p38 mitogen-activated protein (MAP) kinase, extracellular signal-regulated kinase (Erk), and c-Jun-NH2-terminal kinase (JNK) in RANTES production by IV-infected human bronchial epithelial cells. The results showed that IV infection induced increases in p38 MAP kinase, and Erk and JNK phosphorylation and activity. SB 203580, PD 98059, and CEP-1347 attenuated IV-infection induced p38 MAP kinase activity, Erk activity, and JNK activity, respectively. SB 203580 and CEP-1347 attenuated RANTES production by 45.3% and 45.2%, respectively, but a combination of these inhibitors additively attenuated by 69.1%. In contrast, PD 98059 did not attenuate. Anti-IL-1α mAb, anti-IL-1β mAb, anti-TNF-α mAb, anti-IL-8 mAb, anti-IFN-β mAb, anti-RANTES mAb, and a combination of these mAbs did not affect IV infection-induced increases in p38 MAP kinase, Erk, and JNK phosphorylation, indicating that each cytokine neutralized by corresponding Ab was not involved in IV infection-induced phosphorylation of MAP kinases. N-acetylcysteine (NAC) did not affect IV infection-induced increases in MAP kinase phosphorylation, whereas NAC attenuated RANTES production by 18.2%, indicating that reactive oxygen species may act as a second messenger leading to RANTES production via p38 MAP kinase- and JNK-independent pathway. These results indicate that p38 MAP kinase and JNK, at least in part, regulate RANTES production by bronchial epithelial cells.
Superfibronectin, a Multimeric Form of Fibronectin, Increases HIV Infection of Primary CD4+ T Lymphocytes
Authors: Tellier Marinka C. , Greco Giampaolo , Klotman Mary , Mosoian Arevik , Cara Andrea , Arap Wadih , Ruoslahti Erkki , Pasqualini Renata , Schnapp Lynn M. 
Published: April 2014

Abstract
The ability of viruses and bacteria to interact with the extracellular matrix plays an important role in their infectivity and pathogenicity. Fibronectin is a major component of the extracellular matrix in lymph node tissue, the main site of HIV deposition and replication during the chronic phase of infection. Therefore, we asked whether matrix fibronectin (FN) could affect the ability of HIV to infect lymphocytes. To study the role of matrix FN on HIV infection, we used superfibronectin (sFN), a multimeric form of FN that closely resembles in vivo matrix FN. In this study we show that HIV-1IIIB efficiently binds to multimeric fibronectin (sFN) and that HIV infection of primary CD4+ lymphocytes is enhanced by &gt;1 order of magnitude in the presence of sFN. This increase appears to be due to increased adhesion of viral particles to the cell surface in the presence of sFN, followed by internalization of virus. Enzymatic removal of cell surface proteoglycans inhibited the adhesion of HIV-1IIIB/sFN complexes to lymphocytes. In contrast, Abs to integrins had no effect on binding of HIV-1IIIB/sFN complexes to lymphocytes. The III1-C peptide alone also bound HIV-1IIIB efficiently and enhanced HIV infection, although not as effectively as sFN. HIV-1IIIB gp120 envelope protein binds to the III1-C region of sFN and may be important in the interaction of virus with matrix FN. We conclude that HIV-1IIIB specifically interacts with the III1-C region within matrix FN, and that this interaction may play a role in facilitating HIV infection in vivo, particularly in lymph node tissue.
A Poxvirus Protein That Binds to and Inactivates IL-18, and Inhibits NK Cell Response
Authors: Born Teresa L. , Morrison Lynda A. , Esteban David J. , VandenBos Tim , Thebeau Lydia G. , Chen Nanhai , Spriggs Melanie K. , Sims John E. , Buller R. Mark L. 
Published: April 2014

Abstract
IL-18 induces IFN-γ and NK cell cytotoxicity, making it a logical target for viral antagonism of host defense. We demonstrate that the ectromelia poxvirus p13 protein, bearing homology to the mammalian IL-18 binding protein, binds IL-18, and inhibits its activity in vitro. Binding of IL-18 to the viral p13 protein was compared with binding to the cellular IL-18R. The dissociation constant of p13 for murine IL-18 is 5 nM, compared with 0.2 nM for the cellular receptor heterodimer. Mice infected with a p13 deletion mutant of ectromelia virus had elevated cytotoxicity for YAC-1 tumor cell targets compared with control animals. Additionally, the p13 deletion mutant virus exhibited decreased levels of infectivity. Our data suggest that inactivation of IL-18, and subsequent impairment of NK cell cytotoxicity, may be one mechanism by which ectromelia evades the host immune response.
CD14 Employs Hydrophilic Regions to “Capture” Lipopolysaccharides
Authors: Cunningham Mark D. , Shapiro Robert A. , Seachord Carrie , Ratcliffe Kent , Cassiano Linda , Darveau Richard P. 
Published: April 2014

Abstract
CD14 participates in the host innate inflammatory response to bacterial LPS obtained from Escherichia coli and other Gram-negative bacteria. Evidence from several laboratories suggests that different regions of the amino-terminal portion of the molecule may be involved in LPS binding. In this report a series of single-residue serine replacement and charge reversal mutations were generated to further elucidate the mechanism by which this protein may bind a multitude of different LPS ligands. Single-residue CD14 mutation proteins were examined for their ability to bind LPS obtained from E. coli, Porphyromonas gingivalis, and Helicobacter pylori and facilitate the activation of E-selectin from human endothelial cells. In addition, the single-residue CD14 mutation proteins were employed to perform monoclonal epitope-mapping studies with three LPS-blocking Abs that bound tertiary epitopes. Evidence that several different hydrophilic regions of the amino-terminal region of CD14 are involved in LPS binding was obtained. Epitope-mapping studies revealed that these hydrophilic regions are located on one side of the protein surface. These studies suggest that CD14 employs a charged surface in a manor similar to the macrophage scavenger receptor to “capture” LPS ligands and “present” them to other components of the innate host defense system.
Role of CCAAT/Enhancer-Binding Protein Site in Transcription of Human Neutrophil Peptide-1 and -3 Defensin Genes
Authors: Tsutsumi-Ishii Yuko , Hasebe Takeshi , Nagaoka Isao 
Published: April 2014

Abstract
The human neutrophil defensins (human neutrophil peptides (HNPs)), major components of azurophilic granules, contribute to innate and acquired host immunities through their potent antimicrobial activities and ability to activate T cells. Despite being encoded by nearly identical genes, HNP-1 is more abundant in the granules than HNP-3. We investigated the regulation of HNP-1 and HNP-3 expression at the transcriptional level using a promyelocytic HL-60 cell line. Luciferase analysis showed that transcriptional levels of HNP-1 and HNP-3 promoters were equivalent and that an ∼200-bp region identical between promoters was sufficient for transcriptional activity. Furthermore, overlapping CCAAT/enhancer-binding protein (C/EBP) and c-Myb sites in the region were found to be required for efficient transcription. Gel mobility shift assay demonstrated that C/EBPα predominantly bound to the C/EBP/c-Myb sites using HL-60 nuclear extracts. No specific binding to C/EBP/c-Myb sites was observed in nuclear extracts from mature neutrophils, which expressed neither C/EBPα protein nor HNP mRNAs. Taken together, these findings suggest that the difference in the amounts of HNP-1 and HNP-3 peptides in neutrophils is caused by posttranscriptional regulation and that C/EBPα plays an important role in the transcription of HNP genes in immature myeloid cells.
Chemokines Fail to Up-Regulate β1 Integrin-Dependent Adhesion in Human Th2 T Lymphocytes
Authors: Clissi Barbara , D’Ambrosio Daniele , Geginat Jens , Colantonio Lucia , Morrot Alexander , Freshney Norman W. , Downward Julian , Sinigaglia Francesco , Pardi Ruggero 
Published: April 2014

Abstract
Th1 and Th2 cells are functionally distinct subsets of CD4+ T lymphocytes whose tissue-specific homing to sites of inflammation is regulated in part by the differential expression of P- and E-selectin ligands and selected chemokine receptors. Here we investigated the expression and function of β1 integrins in Th1 and Th2 cells polarized in vitro. Th1 lymphocytes adhere transiently to the extracellular matrix ligands laminin 1 and fibronectin in response to chemokines such as RANTES and stromal cell-derived factor-1, and this process is paralleled by the activation of the Rac1 GTPase and by a rapid burst of actin polymerization. Selective inhibitors of phosphoinositide-3 kinase prevent efficiently all of the above processes, whereas the protein kinase C inhibitor bisindolylmaleimide prevents chemokine-induced adhesion without affecting Rac1 activation and actin polymerization. Notably, chemokine-induced adhesion to β1 integrin ligands is markedly reduced in Th2 cells. Such a defect cannot be explained by a reduced sensitivity to chemokine stimulation in this T cell subset, nor by a defective activation of the signaling cascade involving phosphoinositide-3 kinase, Rac1, and actin turnover, as all these processes are activated at comparable levels by chemokines in the two subsets. We propose that reduced β1 integrin-mediated adhesion in Th2 cells may restrain their ability to invade and/or reside in sites of chronic inflammation, which are characterized by thickening of basement membranes and extensive fibrosis, requiring efficient interaction with organized extracellular matrices.
Leukocyte Arrest During Cytokine-Dependent Inflammation In Vivo
Authors: Kunkel Eric J. , Dunne Jessica L. , Ley Klaus 
Published: April 2014

AbstractLeukocyte rolling along the walls of inflamed venules precedes their adhesion during inflammation. Rolling leukocytes are thought to arrest by engaging β2 integrins following cellular activation. In vitro studies suggest that chemoattractants may instantaneously activate and arrest rolling leukocytes. However, how leukocytes stop rolling and become adherent in inflamed venules in vivo has remained rather mysterious. In this paper we use a novel method of tracking individual leukocytes through the microcirculation to show that rolling neutrophils become progressively activated while rolling down the venular tree. On average, leukocytes in wild-type mice roll for 86 s (and cover 270 μm) before becoming adherent with an efficiency around 90%. These rolling leukocytes exhibit a gradual β2 integrin-dependent decrease in rolling velocity that correlates with an increase in intracellular free calcium concentration before arrest. Similar tracking analyses in gene-targeted mice demonstrate that the arrest of rolling leukocytes is very rare when β2 integrins are absent or blocked by a mAb. Arrest is ∼50% less efficient in the absence of E-selectin. These data suggest a model of leukocyte recruitment in which β2 integrins play a critical role in stabilizing leukocyte rolling during a protracted cellular activation period before arrest and firm adhesion.
IFN-γ-Dependent and -Independent Mechanisms in Adverse Effects Caused by Concomitant Administration of IL-18 and IL-12
Authors: Nakamura Shuji , Otani Takeshi , Ijiri Yoshihiro , Motoda Ryuichi , Kurimoto Masashi , Orita Kunzo 
Published: April 2014

Abstract
IL-18 is a new type of inflammatory cytokine similar to but distinct from IL-12 and IL-1β. One intriguing property of IL-18 is synergism with IL-12 in many respects. In this study we examined the in vivo synergistic effects of IL-18/IL-12 in mice and found lethal toxicity accompanying an elevated IFN-γ level in the serum. Since treatment with IL-18 alone did not have any apparent toxicity, and treatment with IL-12 alone showed only limited toxicity in our system, the synergy between the two cytokines was all the more remarkable. The major symptoms of the toxicity were weight loss, diarrhea, hemorrhagic colitis, splenomegaly, fatty liver, and atrophic thymus, most of which are similarly found in endotoxin-induced septic shock. However, in contrast to septic shock, TNF-α was not induced. The involvement of IFN-γ in the toxicity was further studied in detail. Treatment of athymic nude mice with anti-asialo-GM1 did not reduce the toxicity, whereas anti-IFN-γ treatment of wild-type mice alleviated it. When IFN-γ-deficient mice were treated with IL-18/IL-12, the majority of them showed mortality and toxicity with severe pulmonary edema. These results indicate that IL-18/IL-12 treatment induces severe adverse effects through not only IFN-γ-dependent mechanisms but also IFN-γ-independent processes.
α4 Integrin-Dependent Leukocyte Recruitment Does Not Require VCAM-1 in a Chronic Model of Inflammation
Authors: Johnston Brent , Chee Alex , Issekutz Thomas B. , Ugarova Tatiana , Fox-Robichaud Alison , Hickey Michael J. , Kubes Paul 
Published: April 2014

AbstractRats immunized with Mycobacterium butyricum in Freund’s adjuvant develop a chronic vasculitis, with large increases in leukocyte rolling and adhesion in mesenteric postcapillary venules that are significantly inhibited with an α4 integrin Ab. Using intravital microscopy to visualize chronically inflamed microvessels, we demonstrated that α4 integrin-dependent leukocyte rolling and adhesion was inhibited with a β1 integrin, but not a β7 integrin Ab. To date, VCAM-1 has been presumed to be the primary ligand for α4β1 integrin in the vasculature. However, α4β1 integrin-dependent interactions were not reduced by monoclonal or polyclonal VCAM-1 Abs or a VCAM-1 antisense oligonucleotide despite increased VCAM-1 expression in the mesenteric vasculature. To ensure that the VCAM-1 Abs were functional and used at saturating concentrations, blood from Ab-treated rats was perfused over monolayers of CHO cells transfected with rat VCAM-1. Sufficient α4 integrin or VCAM-1 Ab was present to inhibit leukocyte interactions with rat VCAM-1 by 95–100%. Under in vitro flow conditions, only mononuclear leukocytes were recruited from blood of control rats onto purified VCAM-1. However, neutrophils were also recruited onto VCAM-1 from whole blood of adjuvant-immunized animals via α4 integrin. Another ligand for α4β1 integrin is the connecting segment-1 (CS-1) region of fibronectin. An Ab to the CS-1 portion of fibronectin, which did not reduce rolling and adhesion in adjuvant arthritis animals, completely inhibited leukocyte adhesion to CS-1 under static conditions. These findings provide the first evidence that α4β1 integrin-dependent leukocyte rolling and adhesion can occur in vivo via a mechanism other than VCAM-1.
The Coupling of 5-Oxo-Eicosanoid Receptors to Heterotrimeric G Proteins
Authors: O’Flaherty Joseph T. , Taylor Jennifer S. , Kuroki Mitsuyuki 
Published: April 2014

Abstract
5-Oxo-eicosatetraenoic acid (5-oxoETE) stimulated human neutrophil (PMN) and eosinophil chemotaxis, PMN hexose uptake, and PMN membrane GTP/GDP exchange. Pertussis toxin (PT), a blocker of heterotrimeric G proteins (GP), completely inhibited these responses, but proved far less effective on the same responses when elicited by leukotriene B4, C5a, FMLP, platelet-activating factor, IL-8, or RANTES chemotactic factors. 5-OxoETE also specifically bound to the membrane preparations that conducted GTP/GDP exchange. This binding was down-regulated by GTPγS, but not ADPγS, and displaced by 5-oxoETE analogues, but not by leukotriene B4, lipoxin A4, or lipoxin B4. Finally, PMN expressed PT-sensitive GP αι2 and PT-resistant GP αq/11- and α13-chains; eosinophils expressed only αi2 and αq/11. We conclude that 5-oxoETE activates granulocytes through a unique receptor that couples preferentially to PT-sensitive GP. The strict dependency of this putative receptor on PT-sensitive GP may underlie the limited actions of 5-oxoETE, compared with other CF, and help clarify the complex relations between receptors, GP, cell signals, and cell responses.
Expression and Activation of NF-κB in the Antrum of the Human Stomach
Authors: van den Brink Gijs R. , ten Kate Fiebo J. , Ponsioen Cyriel Y. , Rive Maaike M. , Tytgat Guido N. , van Deventer Sander J. H. , Peppelenbosch Maikel P. 
Published: April 2014

Abstract
Both in vitro studies and experiments in mice suggest a key role for transcription factor NF-κB as a mediator of mucosal inflammation. Experiments in vitro show that NF-κB activation may be a critical event in the production of proinflammatory molecules in Helicobacter pylori-associated gastritis. This study examines the expression and activity of NF-κB in situ in antral biopsies of 69 consecutive patients with immunohistochemical techniques. In the uninflamed stomach, NF-κB was highly expressed and active in a subset of epithelial cells, which were identified as predominantly G cells. In accordance with this activity, G cells were shown to express high levels of the NF-κB target cytokine TNF-α, a well-documented stimulator of gastrin production. In patients with H. pylori-associated gastritis, NF-κB activity was markedly enhanced. Activation occurred preferentially in the epithelial cells. The number of cells showing activated NF-κB correlated with the activity of gastritis, a measure of neutrophil influx, whereas no correlation was found with the chronicity of inflammation, a measure of the presence of mononuclear inflammatory cells. This correlation is direct evidence of the importance of NF-κB-dependent signal transduction for neutrophil influx in H. pylori-associated gastritis.
CD4+ T Cell and Eosinophil Adhesion Is Mediated by Specific ICAM-3 Ligation and Results in Eosinophil Activation
Authors: Douglas Ivor S. , Leff Alan R. , Sperling Anne I. 
Published: April 2014

AbstractT cells and eosinophils, which are found in close proximity in asthmatic lungs, express many surface receptors that are counterligands. These data suggest that direct interactions between these cell types could play an important role in regulating airway inflammation in asthma. We examined the effect of selective adhesion between counterligands on human eosinophils and CD4+ T cells to determine 1) the existence of specific adhesive interactions and 2) if augmented specific adhesion to CD4+ T cells also caused augmented secretion of leukotriene C4 (LTC4) from eosinophils. A new method for binding of human CD4+ T cells to microwell plates was developed, which allowed for specific quantitative assessment of eosinophil adhesion to individual CD4+ T cells in culture. Adhesion of CD4+ T cells to eosinophils was minimal in unstimulated cells but increased after activation of T cells by PMA. Augmented adhesion was regulated substantially through binding of ICAM-3 and only minimally by ICAM-1. We further evaluated whether this specific adhesion up-regulated stimulated secretion of LTC4 from eosinophils. Adhesion with CD4+ T cells augmented eosinophil secretion of LTC4 caused by FMLP plus cytochalasin. Blockade of ICAM-3, as well as ICAM-1, inhibited completely the augmented secretion of eosinophil LTC4. We demonstrate that eosinophils and CD4+ T cells are capable of ligand-specific adhesion that is mediated predominantly by ICAM-3 ligation and that this binding causes augmented eosinophil secretion.
Cutaneous Injection of Human Subjects with Macrophage Inflammatory Protein-1α Induces Significant Recruitment of Neutrophils and Monocytes
Authors: Lee Sang Chin , Brummet Mary E. , Shahabuddin Syed , Woodworth Thasia G. , Georas Steve N. , Leiferman Kristin M. , Gilman Steven C. , Stellato Cristiana , Gladue Ron P. , Schleimer Robert P. , Beck Lisa A. 
Published: April 2014

Abstract
Macrophage inflammatory protein (MIP-1α), a member of the CC chemokine subfamily, has been shown to attract T cells and monocytes in vitro and to be expressed at sites of inflammation. Although the in vitro activities of MIP-1α have been well documented, the in vivo biological activities of MIP-1α in humans have not been studied. To address this, we challenged human subjects by intradermal injection with up to 1000 pmol of MIP-1α and performed biopsies 2, 10, and 24 h later. Although no acute cutaneous or systemic reactions were noted, endothelial cell activation, as indicated by the expression of E-selectin, was observed. In agreement with its in vitro activity, monocyte, lymphocyte, and, to a lesser degree, eosinophil infiltration was observed, peaking at 10–24 h. Surprisingly, in contrast to its reported lack of in vitro neutrophil-stimulating activity, a rapid infiltration of neutrophils was observed in vivo. This neutrophil infiltration occurred as early as 2 h, preceding the appearance of other cells, and peaked at 10 h. Interestingly, we found that neutrophils in whole blood, but not after isolation, expressed CCR1 on their cell surface. This CCR1 was thought to be functional as assessed by neutrophil CD11b up-regulation following whole-blood MIP-1α stimulation. These studies substantiate the biological effects of MIP-1α on monocytes and lymphocytes and uncover the previously unrecognized activity of MIP-1α to induce neutrophil infiltration and endothelial cell activation, underscoring the need to evaluate chemokines in vivo in humans.
Genetic Analysis of the Influence of Pertussis Toxin on Experimental Allergic Encephalomyelitis Susceptibility: An Environmental Agent Can Override Genetic Checkpoints
Authors: Blankenhorn Elizabeth P. , Butterfield Russell J. , Rigby Robert , Cort Laura , Giambrone Dana , McDermott Paul , McEntee Kay , Solowski Nancy , Meeker Nathan D. , Zachary James F. , Doerge Rebecca W. , Teuscher Cory 
Published: April 2014

AbstractPertussis toxin (PTX) is a potent ancillary adjuvant used to elicit several different autoimmune diseases, including experimental allergic encephalomyelitis (EAE). To delineate the genetics of PTX effect in EAE, we mapped EAE-modifying (eae-m) loci in cohorts of backcross mice immunized with and without PTX. In this study, we analyzed the genetic basis of EAE susceptibility and severity and the intermediate phenotypes of mononuclear cell infiltration, suppuration, and demyelination. In animals immunized with PTX, one major locus, eae9, controls disease susceptibility and severity. Eae9 also regulates the extent of mononuclear cell infiltration of the spinal cord in male mice. Without PTX, five eae-m loci were noted, including three new loci in intervals on chromosomes 8 (eae14), 10 (eae17), and 18 (eae18). Taken together, these results suggest that eae9 controls the effects of PTX in EAE susceptibility, and is capable of overriding the other genetic checkpoints in the pathogenesis of this disease.