bluuebunny/crossref_metadata_2025_split huggingface dataset:
Macrophages Produce TGF-β-Induced (β-ig-h3) following Ingestion of Apoptotic Cells and Regulate MMP14 Levels and Collagen Turnover in Fibroblasts
Authors: Nacu Natalia , Luzina Irina G. , Highsmith Kendrick , Lockatell Virginia , Pochetuhen Kerill , Cooper Zachary A. , Gillmeister Michael P. , Todd Nevins W. , Atamas Sergei P. 
Published: April 2014

AbstractPhagocytic clearance of apoptotic cells by macrophages is an essential part in the resolution of inflammation. It coincides with activation of repair mechanisms, including accumulation of extracellular matrix. A possible link between clearance of apoptotic debris and accumulation of extracellular matrix has not been investigated. Production of collagen was measured in primary fibroblasts cocultured with macrophages. Ingestion of apoptotic cells by monocyte-derived macrophages led to up-regulation of collagen. Direct contact between macrophages and fibroblasts was not required for collagen up-regulation. Macrophages produced TGF-β following ingestion of apoptotic cells, but the levels of this cytokine were lower than those required for a significant up-regulation of collagen. Simultaneously, the levels of TGF-β-induced (TGFBI), or keratoepithelin/BIGH3, mRNA and protein were increased. In contrast, primary alveolar macrophages stimulated collagen production without exposure to apoptotic cells; there was no further increase in the levels of TGFBI, mRNA or protein, or collagen after ingestion of apoptotic cells. Stimulation of fibroblasts with TGFBI down-regulated MMP14 levels, decreased DNA binding by p53, increased DNA binding by PU.1, and up-regulated collagen protein but not mRNA levels. Overexpression of MMP14 or p53, or small interfering RNA-mediated inhibition of PU.1 led to an increase in MMP14 and a decline in collagen levels, whereas small interfering RNA-mediated inhibition of MMP14 led to elevation of collagen levels. In conclusion, monocyte-derived but not alveolar macrophages produce TGFBI following ingestion of apoptotic cells, leading to the down-regulation of MMP14 levels in fibroblasts through a mechanism involving p53 and PU.1, and to subsequent accumulation of collagen.
Human CD4+ T Cells Recognize an Epitope within α-Fetoprotein Sequence and Develop into TGF-β-Producing CD4+ T Cells
Authors: Alisa Akeel , Boswell Sandra , Pathan Ansar A. , Ayaru Lakshmana , Williams Roger , Behboudi Shahriar 
Published: April 2014

Abstract
There is limited information on the influence of tumor growth on the expansion of tumor-specific TGF-β-producing CD4+ T cells in humans. α-Fetoprotein (AFP) is an oncofetal Ag and has intrinsic immunoregulatory properties. In this study, we report the identification and characterization of subsets of CD4+ T cells that recognize an epitope within the AFP sequence (AFP46–55) and develop into TGF-β-producing CD4+ T cells. In a peptide-specific and dose-dependent manner, AFP46–55 CD4+ T cells produce TGF-β, GM-CSF, and IL-2 but not Th1-, Th2-, Th17-, or Tr1-type cytokines. These cells express CTLA-4 and glucocorticoid-induced TNR receptor and inhibit T cell proliferation in a contact-dependent manner. In this study, we show that the frequency of AFP46–55 CD4+ T cells is significantly higher (p = 001) in patients with hepatocellular carcinoma than in healthy donors, suggesting that these cells are expanded in response to tumor Ag. In contrast, tumor necrosis-inducing treatments that are shown to improve survival rate can shift the Th1/TGF-β-producing CD4+ T cell balance in favor of Th1 responses. Our data demonstrate that tumor Ags may contain epitopes which activate the expansion of inducible regulatory T cells, leading to evasion of tumor control.
Zebrafish TRIF, a Golgi-Localized Protein, Participates in IFN Induction and NF-κB Activation
Authors: Fan Shan , Chen Shangwu , Liu Yanhui , Lin Yiqun , Liu Hui , Guo Lei , Lin Bin , Huang Shengfeng , Xu Anlong 
Published: April 2014

AbstractThe antiviral immune responses were triggered by the innate immune recognition of viral infection. The type I IFNs (IFN-β and IFN-α) are the key cytokines produced upon viral infection and consequently link innate immunity with adaptive immunity. A main antiviral system in mammals is TRIF-dependent TLRs pathway, but the TRIF-independent RIG-I pathway, has also been discovered recently. In this manuscript, our study focuses on the functional characterization of zebrafish TRIF based on the comparison of its sequence and functional evolution from zebrafish to mammals. Our experimental results show that the full length cDNA of zebrafish TRIF cloned by RACE-PCR approach encodes a protein of 556 amino acids. Luciferase reporter assay confirms that zebrafish TRIF is able to induce the IFN promoter as well as activate NF-κB response promoter. The IFN induction function of zebrafish TRIF is abolished when Ala359 is mutated to Pro or His. Laser confocal microscopy shows that zebrafish TRIF is colocalized with a Golgi apparatus marker, implying its unique subcellular localization in Golgi apparatus. In zebrafish, the mRNA expression of molecules participating in RIG-I pathway are much more sensitive and specific to polyinosine-polycytidylic acid induction compared with those in TRIF-dependent antiviral pathway. The TRIF-dependent TLR4 IFN induction signaling appears not to be functional in zebrafish, since IFN expression cannot be up-regulated by LPS. These two striking findings from de novo ligand induction experiments suggest a novel antiviral mechanism in zebrafish.
Unique Effects of KIT D816V in BaF3 Cells: Induction of Cluster Formation, Histamine Synthesis, and Early Mast Cell Differentiation Antigens
Authors: Mayerhofer Matthias , Gleixner Karoline V. , Hoelbl Andrea , Florian Stefan , Hoermann Gregor , Aichberger Karl J. , Bilban Martin , Esterbauer Harald , Krauth Maria-Theresa , Sperr Wolfgang R. , Longley Jack B. , Kralovics Robert , Moriggl Richard , Zappulla Jacques , Liblau Roland S. , Schwarzinger Ilse , Sexl Veronika , Sillaber Christian , Valent Peter 
Published: April 2014

Abstract
Oncogenic tyrosine kinases (TK) usually convert growth factor-dependent cells to factor independence with autonomous proliferation. However, TK-driven neoplasms often are indolent and characterized by cell differentiation rather than proliferation. A prototype of an indolent TK-driven neoplasm is indolent systemic mastocytosis. We found that the D816V-mutated variant of KIT, a TK detectable in most patients with systemic mastocytosis, induces cluster formation and expression of several mast cell differentiation and adhesion Ags, including microphthalmia transcription factor, IL-4 receptor, histamine, CD63, and ICAM-1 in IL-3-dependent BaF3 cells. By contrast, wild-type KIT did not induce cluster formation or mast cell differentiation Ags. Additionally, KIT D816V, but not wild-type KIT, induced STAT5 activation in BaF3 cells. However, despite these intriguing effects, KIT D816V did not convert BaF3 cells to factor-independent proliferation. Correspondingly, BaF3 cells with conditional expression of KIT D816V did not form tumors in nude mice. Together, the biologic effects of KIT D816V in BaF3 cells match strikingly with the clinical course of indolent systemic mastocytosis and with our recently established transgenic mouse model, in which KIT D816V induces indolent mast cell accumulations but usually does not induce a malignant mast cell disease. Based on all these results, it is hypothesized that KIT D816V as a single hit may be sufficient to cause indolent systemic mastocytosis, whereas additional defects may be required to induce aggressive mast cell disorders.
Homeostatic Intracellular-Free Ca2+ Is Permissive for Rap1-Mediated Constitutive Activation of α4 Integrins on Eosinophils
Authors: Ulfman Laurien H. , Kamp Vera M. , van Aalst Corneli W. , Verhagen Liesbeth P. , Sanders Marjolein E. , Reedquist Kris A. , Buitenhuis Miranda , Koenderman Leo 
Published: April 2014

AbstractAlthough much progress has been made in understanding the molecular mechanisms underlying agonist-induced “inside-out” activation of integrins, little is known about how basal levels of integrin function are maintained. This is particularly important for nonactivated eosinophils, where intermediate activation of α4β1 integrin supports recruitment to endothelial cells under flow conditions. Depletion of intracellular Ca2+ and pharmacological inhibition of phospholipase C (but not other intracellular signaling molecules, including PI3K, ERK1/2, p38 MAPK, and tyrosine kinase activity) abrogated basal α4 integrin activity in nonactivated eosinophils. Basal α4 integrin activation was associated with activation of the small GTPase Rap1, a known regulator of agonist-induced integrin function. Basal Rap activation was dependent upon phospholipase C, but not intracellular Ca2+. However, depletion of intracellular Ca2+ in CD34+ hematopoietic progenitor cells abolished RapV12-mediated induction of α4 integrin activity. Thus, residual Rap activity or constitutively active Rap activity in Ca2+-depleted cells is not sufficient to induce α4 integrin activation. These data suggest that activation of functional α4 integrin activity in resting eosinophils is mediated by Rap1 provided that the intracellular-free Ca2+ is at a normal homeostatic concentration.
Utilization of Fc Receptors as a Mucosal Vaccine Strategy against an Intracellular Bacterium, Francisella tularensis
Authors: Rawool Deepak B. , Bitsaktsis Constantine , Li Ying , Gosselin Diane R. , Lin Yili , Kurkure Nitin V. , Metzger Dennis W. , Gosselin Edmund J. 
Published: April 2014

Abstract
Numerous studies have demonstrated that targeting Ag to Fc receptors (FcR) on APCs can enhance humoral and cellular immunity. However, studies are lacking that examine both the use of FcR-targeting in generating immune protection against infectious agents and the use of FcRs in the induction of mucosal immunity. Francisella tularensis is a category A intracellular mucosal pathogen. Thus, intense efforts are underway to develop a vaccine against this organism. We hypothesized that protection against mucosal infection with F. tularensis would be significantly enhanced by targeting inactivated F. tularensis live vaccine strain (iFt) to FcRs at mucosal sites, via intranasal immunization with mAb-iFt complexes. These studies demonstrate for the first time that: 1) FcR-targeted immunogen enhances immunogen-specific IgA production and protection against subsequent infection in an IgA-dependent manner, 2) FcγR and neonatal FcR are crucial to this protection, and 3) inactivated F. tularensis, when targeted to FcRs, enhances protection against the highly virulent SchuS4 strain of F. tularensis, a category A biothreat agent. In summary, these studies show for the first time the use of FcRs as a highly effective vaccination strategy against a highly virulent mucosal intracellular pathogen.
NK Cells Play a Critical Protective Role in Host Defense against Acute ExtracellularStaphylococcus aureusBacterial Infection in the Lung
Authors: Small Cherrie-Lee , McCormick Sarah , Gill Navkiran , Kugathasan Kapilan , Santosuosso Michael , Donaldson Nickett , Heinrichs David E. , Ashkar Ali , Xing Zhou 
Published: April 2014

AbstractStaphylococcus aureus remains a common cause of nosocomial bacterial infections and are often antibiotic resistant. The role of NK cells and IL-15 and their relationship in host defense against extracellular bacterial pathogens including S. aureus remain unclear. We have undertaken several approaches to address this issue using wild type (WT), IL-15 gene knock-out (KO), and NK cell-depleted mouse models. Upon pulmonary staphylococcal infection WT mice had markedly increased activated NK cells, but not NKT or γδ T cells, in the airway lumen that correlated with IL-15 production in the airway and with alveolar macrophages. In vitro exposure to staphylococcal products and/or coculture with lung macrophages directly activated NK cells. In contrast, lung macrophages better phagocytosed S. aureus in the presence of NK cells. In sharp contrast to WT controls, IL-15 KO mice deficient in NK cells were found to be highly susceptible to pulmonary staphylococcal infection despite markedly increased neutrophils and macrophages in the lung. In further support of these findings, WT mice depleted of NK cells were similarly susceptible to staphylococcal infection while they remained fully capable of IL-15 production in the lung at levels similar to those of NK-competent WT hosts. Our study thus identifies a critical role for NK cells in host defense against pulmonary extracellular bacterial infection and suggests that IL-15 is involved in this process via its indispensable effect on NK cells, but not other innate cells. These findings hold implication for the development of therapeutics in treating antibiotic-resistant S. aureus infection.
The Tyrosine Kinase Pyk2 Mediates Lipopolysaccharide-Induced IL-8 Expression in Human Endothelial Cells
Authors: Anand Appakkudal R. , Cucchiarini Magali , Terwilliger Ernest F. , Ganju Ramesh K. 
Published: April 2014

Abstract
Secretion of proinflammatory cytokines by LPS activated endothelial cells contributes substantially to the pathogenesis of sepsis. However, the mechanism involved in this process is not well understood. In the present study, we determined the role of a nonreceptor proline-rich tyrosine kinase, Pyk2, in LPS-induced IL-8 (CXCL8) production in endothelial cells. First, we observed a marked activation of Pyk2 in response to LPS. Furthermore, inhibition of Pyk2 activity in these cells by transduction with the catalytically inactive Pyk2 mutant, transfection with Pyk2-specific small interfering RNA, or treatment with Tyrphostin A9 significantly blocked LPS-induced IL-8 production. The supernatants of LPS-stimulated cells exhibiting attenuated Pyk2 activity blocked transendothelial neutrophil migration in comparison to the supernatants of LPS-treated controls, thus confirming the inhibition of functional IL-8 production. Investigations into the molecular mechanism of this pathway revealed that LPS activates Pyk2 leading to IL-8 production through the TLR4. In addition, we identified the p38 MAPK pathway to be a critical step downstream of Pyk2 during LPS-induced IL-8 production. Taken together, these results demonstrate a novel role for Pyk2 in LPS-induced IL-8 production in endothelial cells.
CRTH2 Plays an Essential Role in the Pathophysiology of Cry j 1-Induced Pollinosis in Mice
Authors: Nomiya Rie , Okano Mitsuhiro , Fujiwara Tazuko , Maeda Megumi , Kimura Yoshinobu , Kino Kosuke , Yokoyama Minehiko , Hirai Hiroyuki , Nagata Kinya , Hara Toshifumi , Nishizaki Kazunori , Nakamura Masataka 
Published: April 2014

AbstractPGD2 is the major prostanoid produced during the acute phase of allergic reactions. Two PGD2 receptors have been isolated, DP and CRTH2 (chemoattractant receptor-homologous molecule expressed on Th2 cells), but whether they participate in the pathophysiology of allergic diseases remains unclear. We investigated the role of CRTH2 in the initiation of allergic rhinitis in mice. First, we developed a novel murine model of pollinosis, a type of seasonal allergic rhinitis. Additionally, pathophysiological differences in the pollinosis were compared between wild-type and CRTH2 gene-deficient mice. An effect of treatment with ramatroban, a CRTH2/T-prostanoid receptor dual antagonist, was also determined. Repeated intranasal sensitization with Cry j 1, the major allergen of Cryptomeria japonica pollen, in the absence of adjuvants significantly exacerbated nasal hyperresponsive symptoms, Cry j 1-specific IgE and IgG1 production, nasal eosinophilia, and Cry j 1-induced in vitro production of IL-4 and IL-5 by submandibular lymph node cells. Additionally, CRTH2 mRNA in nasal mucosa was significantly elevated in Cry j 1-sensitized mice. Following repeated intranasal sensitization with Cry j 1, CRTH2 gene-deficient mice had significantly weaker Cry j 1-specific IgE/IgG1 production, nasal eosinophilia, and IL-4 production by submandibular lymph node cells than did wild-type mice. Similar results were found in mice treated with ramatroban. These results suggest that the PGD2-CRTH2 interaction is elevated following sensitization and plays a proinflammatory role in the pathophysiology of allergic rhinitis, especially pollinosis in mice.
Production of Type VI Collagen by Human Macrophages: A New Dimension in Macrophage Functional Heterogeneity
Authors: Schnoor Michael , Cullen Paul , Lorkowski Julia , Stolle Katrin , Robenek Horst , Troyer David , Rauterberg Jürgen , Lorkowski Stefan 
Published: April 2014

AbstractMacrophages derived from human blood monocytes perform many tasks related to tissue injury and repair. The main effect of macrophages on the extracellular matrix is considered to be destructive in nature, because macrophages secrete metalloproteinases and ingest foreign material as part of the remodeling process that occurs in wound healing and other pathological conditions. However, macrophages also contribute to the extracellular matrix and hence to tissue stabilization both indirectly, by inducing other cells to proliferate and to release matrix components, and directly, by secreting components of the extracellular matrix such as fibronectin and type VIII collagen, as we have recently shown. We now report that monocytes and macrophages express virtually all known collagen and collagen-related mRNAs. Furthermore, macrophages secrete type VI collagen protein abundantly, depending upon their mode of activation, stage of differentiation, and cell density. The primary function of type VI collagen secreted by macrophages appears to be modulation of cell-cell and cell-matrix interactions. We suggest that the production of type VI collagen is a marker for a nondestructive, matrix-conserving macrophage phenotype that could profoundly influence physiological and pathophysiological conditions in vivo.
In Vitro and In Vivo Down-Regulation of Regulatory T Cell Activity with a Peptide Inhibitor of TGF-β1
Authors: Gil-Guerrero Lucía , Dotor Javier , Huibregtse Inge Louise , Casares Noelia , López-Vázquez Ana Belén , Rudilla Francesc , Riezu-Boj José Ignacio , López-Sagaseta Jacinto , Hermida José , Van Deventer Sander , Bezunartea Jaione , Llopiz Diana , Sarobe Pablo , Prieto Jesús , Borrás-Cuesta Francisco , Lasarte Juan José 
Published: April 2014

Abstract
Down-regulation of CD4+CD25+ regulatory T (Treg) cell function might be beneficial to enhance the immunogenicity of viral and tumor vaccines or to induce breakdown of immunotolerance. Although the mechanism of suppression used by Treg cells remains controversial, it has been postulated that TGF-β1 mediates their immunosuppressive activity. In this study, we show that P17, a short synthetic peptide that inhibits TGF-β1 and TGF-β2 developed in our laboratory, is able to inhibit Treg activity in vitro and in vivo. In vitro studies demonstrate that P17 inhibits murine and human Treg-induced unresponsiveness of effector T cells to anti-CD3 stimulation, in an MLR or to a specific Ag. Moreover, administration of P17 to mice immunized with peptide vaccines containing tumor or viral Ags enhanced anti-vaccine immune responses and improved protective immunogenicity against tumor growth or viral infection or replication. When CD4+ T cells purified from OT-II transgenic mice were transferred into C57BL/6 mice bearing s.c. EG.7-OVA tumors, administration of P17 improved their proliferation, reduced the number of CD4+Foxp3+ T cells, and inhibited tumor growth. Also, P17 prevented development of immunotolerance induced by oral administration of OVA by genetically modified Lactococcus lactis in DO11.10 transgenic mice sensitized by s.c. injection of OVA. These findings demonstrate that peptide inhibitors of TGF-β may be a valuable tool to enhance vaccination efficacy and to break tolerance against pathogens or tumor Ags.
Coligation of the Hepatitis C Virus Receptor CD81 with CD28 Primes Naive T Lymphocytes to Acquire Type 2 Effector Function
Authors: Serra Alessandro , Nuti Sandra , Tavarini Simona , Sammicheli Chiara , Rosa Domenico , Saletti Giulietta , Soldaini Elisabetta , Abrignani Sergio , Wack Andreas 
Published: April 2014

Abstract
Costimuli provide supplementary signals required by naive T cells to become fully activated upon Ag encounter. Tetraspanins are a large family of transmembrane proteins that can costimulate T cells when engaged in vitro. In this study, we describe for the first time that coligation of the tetraspanins CD81, CD82, or CD9 with the costimulatory molecule CD28 in vitro leads to proliferation of naive T cells. When activated through this pathway, both CD4+ and CD8+ naive T cells differentiate into type 2 effector cells, which produce IL-4, IL-5, IL-13, and IL-10, together with IL-2 and TNF-α, but little to no IFN-γ. These effector cells descend from precursors that display early and strong production of IL-4, STAT6 phosphorylation, and up-regulation of the transcription factor GATA-3, suggesting a direct skewing toward Th2 differentiation without a Th0 intermediate. The hepatitis C virus envelope protein E2 is the only ligand known for CD81. Therefore, we propose that this new type of Ag-independent T cell activation may occur in hepatitis C virus-infected individuals, contributing to liver inflammation, impaired type 1 immune responses, and recurrent flares of type 2 immunity associated with chronic infection.
Dual Functions of Bruton’s Tyrosine Kinase and Tec Kinase during Fcγ Receptor-Induced Signaling and Phagocytosis
Authors: Jongstra-Bilen Jenny , Puig Cano Adrianet , Hasija Manvi , Xiao Haiyan , Smith C. I. Edvard , Cybulsky Myron I. 
Published: April 2014

Abstract
Tec family nonreceptor tyrosine kinases are expressed by hematopoietic cells, activate phospholipase C (PLC)γ, and regulate cytoskeletal rearrangement, yet their role in FcγR-induced signaling and phagocytosis remains unknown. We demonstrate in this study that Bruton’s tyrosine kinase (Btk) and Tec, the only Tec kinases expressed by RAW 264.7 cells, are activated throughout phagocytosis. Activated Btk and Tec kinase accumulate at an early stage at the base of phagocytic cups and inhibition of their activity by the specific inhibitor LFM-A13 or expression by small interfering RNA significantly inhibited FcγR-induced phagocytosis. Similarly, a significant role for these kinases in phagocytosis was found in primary macrophages. FcγR-induced activation of Mac-1, which is required for optimal phagocytosis, was markedly inhibited and our findings suggest that the roles of kinases Btk and Tec in Mac-1 activation account for their functions in the early stages of phagocytosis. Initial activation of PLCγ2, the predominant PLC isoform in RAW 264.7 cells, is dependent on Syk. In contrast, a late and prolonged activation of PLCγ2 was dependent on Btk and Tec. We found accumulation of diacylglycerol (DAG), a PLCγ product, in phagosome membranes, and activated Btk, but not Tec, colocalized with phagosomal DAG. Inhibition of Tec family kinase activity increased the level of DAG in phagosomes, suggesting a negative regulatory role for Btk. Tec, in contrast, clustered at sites near phagosome formation. In summary, we elucidated that Tec family kinases participate in at least two stages of FcγR-mediated phagocytosis: activation of Mac-1 during ingestion, and after phagosome formation, during which Btk and Tec potentially have distinct roles.