bluuebunny/crossref_metadata_2025_split huggingface dataset:
Activation of the Neutrophil Nicotinamide Adenine Dinucleotide Phosphate Oxidase by Galectin-1
Authors: Almkvist Jenny , Dahlgren Claes , Leffler Hakon , Karlsson Anna 
Published: April 2014

AbstractGalectins are a group of lactose-binding proteins widely distributed in nature. Twelve mammalian galectins have so far been identified, but their functions are to a large extent unknown. In this work we study galectin-1 in its interaction with human neutrophils, with regard to both cell surface binding and activation of the superoxide-producing NADPH-oxidase. We show that galectin-1 is able to activate the neutrophil NADPH-oxidase, provided that the cells have been primed by extravasation from the blood into the tissue, an activation pattern that is similar to that of galectin-3. Using in vitro priming protocols, the galectin-1 responsiveness was found to correlate to granule mobilization and galectin-1 binding to the cells, suggesting the presence of granule-localized receptors that are up-regulated to the cell surface upon priming. By galectin-1 overlay of fractionated neutrophils we identified potential galectin-1 receptor candidates localized in the membranes of the secretory vesicle and gelatinase granules. The binding of galectin-1 and galectin-3 to neutrophil proteins was compared, as were the dose dependencies for activation by the two lectins. The results suggest that, although similarities are found between the two galectins, they appear to activate the NADPH-oxidase using different receptors. In conclusion, galectin-1 appears to have proinflammatory functions, mediated through activation of the neutrophil respiratory burst.
Monocyte Chemoattractant Protein-1 and 5-Lipoxygenase Products Recruit Leukocytes in Response to Platelet-Activating Factor-Like Lipids in Oxidized Low-Density Lipoprotein
Authors: Silva Adriana R. , de Assis Edson F. , Caiado Lara F. C. , Marathe Gopal K. , Bozza Marcelo T. , McIntyre Thomas M. , Zimmerman Guy A. , Prescott Stephen M. , Bozza Patricia T. , Castro-Faria-Neto Hugo C. 
Published: April 2014

AbstractOxidized low-density lipoprotein (LDL) contains inflammatory agents, including oxidatively fragmented phospholipids that activate the platelet-activating factor (PAF) receptor, but in vivo events caused by these pathologically generated agents are not well defined. Injection of PAF-like lipids derived from oxidized LDL, or C4-PAF that is a major PAF-like lipid in these particles, into the pleural cavity of mice resulted in rapid monocyte, neutrophil, and eosinophil accumulation. Increased numbers of intracellular lipid bodies in these cells show they were in an inflammatory environment. Leukocyte recruitment was abolished by a PAF receptor antagonist, as expected. PAF-like lipids induced 5-lipoxygenase expression in leukocytes, mRNA expression for monocyte chemoattractant protein-1 (MCP-1) and other chemokines, synthesis of MCP-1, and leukotriene B4. The 5-lipoxygenase inhibitor zileuton impaired neutrophil influx, while MCP-1 had a more global role, as determined with MCP-1−/− mice. The lack of MCP-1 abrogated leukocyte accumulation and lipid body formation both in vivo and in vitro and chemokine transcription in vivo, and reduced in vivo leukotriene B4 production. Thus, PAF-like phospholipids in oxidized LDL induce an inflammatory infiltrate through the PAF receptor, chemokine transcription, lipid body formation, and 5-lipoxygenase expression in leukocytes. MCP-1 has a key role in this inflammatory response, and 5-lipoxygenase products are essential for neutrophil recruitment into the inflamed pleural cavity.
IFN-γ Production by Intrinsic Renal Cells and Bone Marrow-Derived Cells Is Required for Full Expression of Crescentic Glomerulonephritis in Mice
Authors: Timoshanko Jennifer R. , Holdsworth Stephen R. , Kitching A. Richard , Tipping Peter G. 
Published: April 2014

AbstractThe contribution of IFN-γ from bone marrow (BM) and non-BM-derived cells to glomerular and cutaneous delayed-type hypersensitivity (DTH) was studied in mice. Chimeric IFN-γ mice (IFN-γ+/+ BM chimera), in which IFN-γ production was restricted to BM-derived cells, were created by transplanting normal C57BL/6 (wild-type (WT)) BM into irradiated IFN-γ-deficient mice. BM IFN-γ-deficient chimeric mice (IFN-γ−/− BM chimera) were created by transplanting WT mice with IFN-γ-deficient BM. WT and sham chimeric mice (WT mice transplanted with WT BM) developed crescentic glomerulonephritis (GN) with features of DTH (including glomerular T cell and macrophage infiltration) in response to an Ag planted in their glomeruli and skin DTH following subdermal Ag challenge. IFN-γ-deficient mice showed significant protection from crescentic GN and reduced cutaneous DTH. IFN-γ+/+ BM chimeric and IFN-γ−/− BM chimeric mice showed similar attenuation of crescentic GN as IFN-γ-deficient mice, whereas cutaneous DTH was reduced only in IFN-γ−/− BM chimeras. In crescentic GN, IFN-γ was expressed by tubular cells and occasional glomerular cells and was colocalized with infiltrating CD8+ T cells, but not with CD4+ T cells or macrophages. Renal MHC class II expression was reduced in IFN-γ+/+ BM chimeric mice and was more severely reduced in IFN-γ-deficient mice and IFN-γ−/− BM chimeric mice. These studies show that IFN-γ expression by both BM-derived cells and intrinsic renal cells is required for the development of crescentic GN, but IFN-γ production by resident cells is not essential for the development of cutaneous DTH.
Gene Expression Profiling in DQA1*0501+ Children with Untreated Dermatomyositis: A Novel Model of Pathogenesis
Authors: Tezak Zivana , Hoffman Eric P. , Lutz Jennica L. , Fedczyna Tamara O. , Stephan Dietrich , Bremer Eric G. , Krasnoselska-Riz Irina , Kumar Ajit , Pachman Lauren M. 
Published: April 2014

AbstractJuvenile dermatomyositis (JDM), the most common pediatric inflammatory myopathy, is a systemic vasculopathy affecting young children. Epidemiology studies documenting an antecedent illness in the 3 mo before the first definite symptom (rash and/or weakness) of JDM are supported by immunologic data that suggest that the disease pathophysiology is Ag driven. The purpose of this study was to compare the gene expression profiles in muscle biopsies of four untreated DQA1*0501+ JDM children with profiles from children with a known necrotizing myopathy (Duchenne muscular dystrophy), as well as an in vitro antiviral model (NF90), and healthy pediatric controls. Nearly half (47%) of the dysregulated genes in JDM were associated with the immune response. In particular, increased expression of IFN-αβ-inducible genes 6-16, myxovirus resistance protein p78, latent cytosolic transcription factor, LMP2, and TAP1 was observed. This profile is consistent with an IFN-αβ transcription cascade seen in the in vitro viral resistance model. The IFN-αβ-inducible profile was superimposed on transcription profiles reflective of myofiber necrosis and regeneration shared with Duchenne muscular dystrophy. Expressed genes were confirmed by quantitative real-time PCR (6-16), immunofluorescence (thrombospondin 4), and immunolocalization (IFN-γ, p21). We hypothesize that these data support a model of Ag (?viral) induction of an apparent autoimmune disease based on dynamic interaction between the muscle, vascular, and immune systems in the genetically susceptible (DQA1*0501+) child.
Depletion of Collagen II-Reactive T Cells and Blocking of B Cell Activation Prevents Collagen II-Induced Arthritis in DBA/1j Mice
Authors: Zhang Huang-Ge , Yang PingAr , Xie Jinfu , Liu Zhongyu , Liu Di , Xiu Liang , Zhou Tong , Wang Yongming , Hsu Hui-Chen , Mountz John D. 
Published: April 2014

AbstractCollagen II (CII)-induced arthritis in DBA/1j mice is mediated by both CII-reactive T cells and anti-CII Ab-producing B cells. To determine the relative role of these processes in the development of arthritis, we specifically eliminated CII-reactive T cells by treating the mice with CII-pulsed syngeneic macrophages that had been transfected with a binary adenovirus system. These macrophages express murine Fas ligand in a doxycycline-inducible manner with autocrine suicide inhibited by concomitant expression of p35. The mice were treated i.v. with four doses of CII-APC-AdFasLp35Tet or a single dose of AdCMVsTACI (5 × 109 PFU), or both simultaneously, beginning 2 wk after priming with CII in CFA. Treatment with CII-APC-AdFasLp35Tet alone or in combination with a single dose of AdCMVsTACI prevented the development of CII-induced arthritis and T cell infiltration in the joint. The elimination of T cells was specific in that a normal T cell response was observed on stimulation with OVA after treatment with CII-APC-AdFasLp35Tet. Treatment with AdCMVsTACI alone prevented production of detectable levels of circulating anti-CII autoantibodies and reduced the severity of arthritis but did not prevent its development. These results indicate that the CII-reactive T cells play a crucial role in the development of CII-induced arthritis and that the anti-CII Abs act to enhance the development of CII-induced arthritis.
A Role for IL-15 in Driving the Onset of Spontaneous Autoimmune Thyroiditis?
Authors: Kaiser Pete , Rothwell Lisa , Vašíček Dusan , Hala Karel 
Published: April 2014

AbstractThe obese strain (OS) of chickens, which suffers from spontaneous autoimmune thyroiditis, is an excellent animal model for Hashimoto’s thyroiditis and provides a unique opportunity to investigate the mechanisms underlying and driving the onset of the disease. Following recent advances in cloning chicken cytokines, we can now begin to investigate the role of cytokines in driving the lymphoid infiltration of the thyroid seen in these birds from day 7 posthatch. Using real-time quantitative RT-PCR, we characterized the expression of IFN-γ, IL-1β, IL-2, IL-6, IL-8, IL-15, and IL-18 in thyroids from OS birds and control CB line birds, both in the embryo just before hatch (embryonic day 20) and at 3 and 5 days posthatch. All of these cytokines were up-regulated compared with levels in thyroids from CB birds, at least at some time points, with some evidence for coordination of regulation, e.g., for the proinflammatory cytokines IL-1β and IL-8. Only IL-15 was up-regulated at all time points. IL-15 was also shown to be up-regulated in spleens of OS birds at embryonic day 20 and 5 days posthatch, suggesting that IL-15 is constitutively up-regulated in this line of birds. This could explain the general immune system hyperreactivity exhibited by OS chickens and may be a factor driving the lymphoid infiltration of the thyroid.
Vaccination with a Melan-A Peptide Selects an Oligoclonal T Cell Population with Increased Functional Avidity and Tumor Reactivity
Authors: Valmori Danila , Dutoit Valerie , Schnuriger Valerie , Quiquerez Anne-Lise , Pittet Mikaël J. , Guillaume Philippe , Rubio-Godoy Verena , Walker Paul R. , Rimoldi Donata , Liénard Danielle , Cerottini Jean-Charles , Romero Pedro , Dietrich Pierre-Yves 
Published: April 2014

AbstractBoth the underlying molecular mechanisms and the kinetics of TCR repertoire selection following vaccination against tumor Ags in humans have remained largely unexplored. To gain insight into these questions, we performed a functional and structural longitudinal analysis of the TCR of circulating CD8+ T cells specific for the HLA-A2-restricted immunodominant epitope from the melanocyte differentiation Ag Melan-A in a melanoma patient who developed a vigorous and sustained Ag-specific T cell response following vaccination with the corresponding synthetic peptide. We observed an increase in functional avidity of Ag recognition and in tumor reactivity in the postimmune Melan-A-specific populations as compared with the preimmune blood sample. Improved Ag recognition correlated with an increase in the t1/2 of peptide/MHC interaction with the TCR as assessed by kinetic analysis of A2/Melan-A peptide multimer staining decay. Ex vivo analysis of the clonal composition of Melan-A-specific CD8+ T cells at different time points during vaccination revealed that the response was the result of asynchronous expansion of several distinct T cell clones. Some of these T cell clones were also identified at a metastatic tumor site. Collectively, these data show that tumor peptide-driven immune stimulation leads to the selection of high-avidity T cell clones of increased tumor reactivity that independently evolve within oligoclonal populations.
Cutting Edge: Molecular Mechanisms of Synergy Between CD40 and the B Cell Antigen Receptor: Role for TNF Receptor-Associated Factor 2 in Receptor Interaction
Authors: Haxhinasto Sokol A. , Hostager Bruce S. , Bishop Gail A. 
Published: April 2014

AbstractOptimal Ag-specific B lymphocyte activation requires both recognition of Ag by the B cell Ag receptor (BCR) and contact-mediated interactions with Ag-specific Th lymphocytes. One of these interactions involves ligation of B cell CD40 by T cell-expressed CD154. CD40 signaling is crucial for Ab production, isotype switching, up-regulation of surface molecules, development of germinal centers, and the humoral memory response. The signaling pathways emanating from the BCR and CD40 are able to cooperate, but the molecular mechanisms responsible for this interaction are incompletely understood. The present study explored the roles of signaling motifs in the CD40 cytoplasmic tail in this synergy. We find that threonine in the PXQXT motif in the TNFR-associated factor-2 binding site is critical for synergistic effects of CD40 and BCR signals, independent of its phosphorylation. Furthermore, data suggest an indirect role for TNFR-associated factor-2 in the cooperative signaling.
Direct Ex Vivo Analysis of Human CD4+ Memory T Cell Activation Requirements at the Single Clonotype Level
Authors: Bitmansour Arlene D. , Douek Daniel C. , Maino Vernon C. , Picker Louis J. 
Published: April 2014

AbstractCD4+ memory T cells continuously integrate signals transmitted through the TCR and costimulatory molecules, only responding when the intensity of such signals exceeds an intrinsic activation threshold. Recent data suggest that these activation thresholds can be regulated independently of TCR specificity, and that threshold tuning may constitute a major mechanism for controlling T cell effector activity. In this work we take advantage of the profound clonotypic hierarchies of the large human CD4+ T cell response to CMV to study activation thresholds of fresh (unexpanded) memory T cells at the clonotypic level. We identified dominant responses to CMV matrix determinants mediated by single TCRB sequences within particular TCR-Vβ families. The specific response characteristics of these single, Ag-specific, TCRB-defined clonotypes could be unequivocally determined in fresh PBMC preparations by cytokine flow cytometry with gating on the appropriate Vβ family. These analyses revealed 1) optimal peptides capable of eliciting specific responses by themselves at doses as low as 2 pg/ml, with each log increase in dose eliciting ever-increasing frequencies of responding cells over a 4- to 5-log range; 2) significant augmentation of response frequencies at all submaximal peptide doses by CD28- and CD49d-mediated costimulation; 3) differential dose response and costimulatory characteristics for IFN-γ and IL-2 responses; and 4) no association of activation requirements with the CD27-defined CD4+ T cell memory differentiation pathway. Taken together these data confirm that triggering heterogeneity exists within individual CD4+ memory T cell clonotypes in vivo and demonstrate that such single clonotypes can manifest qualitatively different functional responses depending on epitope dose and relative levels of costimulation.
Priming Biologically Active Antibody Responses Against an Isolated, Conformational Viral Epitope by DNA Vaccination
Authors: Riedl Petra , El Kholy Shereen , Reimann Jörg , Schirmbeck Reinhold 
Published: April 2014

AbstractThe immunodominant, conformational “a” determinant of hepatitis B surface Ag (HBsAg) elicits Ab responses. We selectively expressed the Ab-binding, glycosylated, native a determinant (residue 120–147) of HBsAg in a fusion protein containing C-terminally the HBsAg fragment SII (residue 80–180) fused to a SV40 T-Ag-derived hsp73-binding 77 aa (T77) or non-hsp-binding 60 aa (T60) N terminus. A DNA vaccine encoding non-hsp-binding secreted T60-SII fusion protein-stimulated murine Ab responses with a similar efficacy as a DNA vaccine encoding the secreted, native, small HBsAg. A DNA vaccine encoding hsp73-binding, intracellular T77-SII fusion protein-stimulated murine Ab responses less efficiently but comparable to a DNA vaccine encoding the intracellular, native, large HBsAg. HBsAg-specific Abs elicited by either the T60-SII-expressing or the T77-SII-expressing DNA vaccine suppressed HBsAg antigenemia in transgenic mice that produce HBsAg from a transgene in the liver; hence, a biologically active B cell response cross-reacting with the native, viral envelope epitope was primed by both DNA vaccine constructs. HBsAg-specific Ab and CTL responses were coprimed when an S20–50 fragment (containing the immunodominant, Ld-binding epitope S28–39) of HBsAg was fused C-terminally to the pCI/T77-SII sequence (pCI/T77-SII-Ld DNA vaccine). Chimeric, polyepitope DNA vaccines encoding conformational, Ab-binding epitopes and MHC class I-binding epitopes can thus efficiently deliver antigenic information to different compartments of the immune system in an immunogenic way.
IFN Consensus Sequence Binding Protein/IFN Regulatory Factor-8 Guides Bone Marrow Progenitor Cells Toward the Macrophage Lineage
Authors: Tsujimura Hideki , Nagamura-Inoue Tokiko , Tamura Tomohiko , Ozato Keiko 
Published: April 2014

Abstract
IFN consensus sequence binding protein (ICSBP; IFN regulatory factor-8) is a transcription factor of the IFN regulatory factor family. Disruption of this gene results in a leukemia-like disease in mice. To investigate the role of ICSBP in myeloid cell development, lineage marker-negative (Lin−) bone marrow progenitor cells were purified from ICSBP+/+ and ICSBP−/− mice and tested for gene expression and colony-forming ability. ICSBP was expressed in Lin− progenitor cells, and its levels were markedly increased by IFN-γ. The colony-forming potential of ICSBP−/− progenitor cells was grossly abnormal, as they gave rise to a disproportionately high number of granulocyte colonies and many fewer macrophage colonies. IFN-γ inhibited colony formation, while promoting macrophage maturation in ICSBP+/+ cells. In contrast, the effects of IFN-γ were completely absent in ICSBP−/− progenitors. By retrovirus transduction we tested whether reintroduction of ICSBP restores a normal colony-forming potential in −/− progenitor cells. The wild-type ICSBP, but not transcriptionally defective mutants, corrected abnormal colony formation by increasing macrophage colonies and decreasing granulocyte colonies. Taken together, ICSBP plays a critical role in myeloid cell development by controlling lineage selection and is indispensable for IFN-γ-dependent modulation of progenitor cell maturation.
Two Distinct Domains Within the N-Terminal Region of Janus Kinase 1 Interact with Cytokine Receptors
Authors: Usacheva Anna , Kotenko Sergei , Witte Michael M. , Colamonici Oscar R. 
Published: April 2014

Abstract
The interaction between receptors and kinases of the Janus kinase (Jak) family is critical for signaling by growth factors, cytokines, and IFNs. Therefore, the characterization of the domains involved in these interactions is pivotal not only in understanding kinase activation but also in the development of drugs that mimic or inhibit signaling. In this report, we have characterized the domains of Jak1 required to associate with distinct cytokine receptor subunits: IFN-αRβL, IFN-γRα, IL-10Rα, IL-2Rβ, and IL-4Rα. We demonstrate that two regions of Jak1 are necessary for the interaction with cytokine receptors. First, a common N-terminal region that includes Jak homology (JH) domain 7 and the first 19 aa of JH6, and, second, a C-terminal region (JH6–3) that was different for distinct receptors. The contribution of the two different regions of Jak1 to cytokine receptor binding was also variable. Deletion of JH7–6 impaired the association of IL-2Rβ and IL-4Rα chains with Jak1 but did not have a major impact on the binding of Jak1 to IFN-αRβL or IL-10Rα. Interestingly, regardless of the effect on receptor binding, removal of JH7–6 completely abrogated kinase activation, indicating that this domain is required for ligand-driven kinase activation and, thus, for proper signaling through cytokine receptors.
Isolation and Detection of Human IgA Using a Streptococcal IgA-Binding Peptide
Authors: Sandin Charlotta , Linse Sara , Areschoug Thomas , Woof Jenny M. , Reinholdt Jesper , Lindahl Gunnar 
Published: April 2014

AbstractBacterial proteins that bind to the Fc part of IgG have found widespread use in immunology. A similar protein suitable for the isolation and detection of human IgA has not been described. Here, we show that a 50-residue synthetic peptide, designated streptococcal IgA-binding peptide (Sap) and derived from a streptococcal M protein, can be used for single-step affinity purification of human IgA. High affinity binding of IgA required the presence in Sap of a C-terminal cysteine residue, not present in the intact M protein. Passage of human serum through a Sap column caused depletion of &gt;99% of the IgA, and elution of the column allowed quantitative recovery of highly purified IgA, for which the proportions of the IgA1 and IgA2 subclasses were the same as in whole serum. Moreover, immobilized Sap could be used for single-step purification of secretory IgA of both subclasses from human saliva, with a recovery of ∼45%. The Sap peptide could also be used to specifically detect IgA bound to Ag. Together, these data indicate that Sap is a versatile Fc-binding reagent that may open new possibilities for the characterization of human IgA.
The Rap GTPases Regulate B Cell Migration Toward the Chemokine Stromal Cell-Derived Factor-1 (CXCL12): Potential Role for Rap2 in Promoting B Cell Migration
Authors: McLeod Sarah J. , Li Anson H. Y. , Lee Rosaline L. , Burgess Anita E. , Gold Michael R. 
Published: April 2014

AbstractStromal cell-derived factor-1 (SDF-1) is a potent chemoattractant for B cells and B cell progenitors. Although the binding of SDF-1 to its receptor, CXCR4, activates multiple signaling pathways, the mechanism by which SDF-1 regulates cell migration is not completely understood. In this report we show that activation of the Rap GTPases is important for B cells to migrate toward SDF-1. We found that treating B cells with SDF-1 resulted in the rapid activation of both Rap1 and Rap2. Moreover, blocking the activation of Rap1 and Rap2 via the expression of a Rap-specific GTPase-activating protein significantly reduced the ability of B cells to migrate toward SDF-1. Conversely, expressing a constitutively active form of Rap2 increased SDF-1-induced B cell migration. Thus, the Rap GTPases control cellular processes that are important for B cells to migrate toward SDF-1.