bluuebunny/crossref_metadata_2025_split huggingface dataset:
IL-1 Induced Chemokine Production Through the Association of Syk with TNF Receptor-Associated Factor-6 in Nasal Fibroblast Lines
Authors: Yamada Takechiyo , Fujieda Shigeharu , Yanagi Shigeru , Yamamura Hirohei , Inatome Ryoko , Yamamoto Hideyuki , Igawa Hideki , Saito Hitoshi 
Published: April 2014

Abstract
The fibroblasts stimulated by cytokines released the chemokine and recruited the infiltrating cells, including eosinophils, that play a key role in the pathogenesis of airway disease. We established the human fibroblast lines showing high Syk expression and the lines showing low Syk expression from pieces of nasal polyp. IL-1 induces the interaction of TNFR-associated factor (TRAF) 6 with IL-1R-associated kinase, which is rapidly recruited to the IL-1R after IL-1 induction, whereas TRAF2 participates in TNF-α-signaling. In the present study, we found that Syk played a different role in IL-1- and TNF-α-induced chemokine production through a signaling complex involving Syk and TRAF6. Overexpression of wild-type Syk by gene transfer enhanced RANTES production from nasal fibroblasts stimulated with IL-1. The decrease of Syk expression by the administration of Syk antisense inhibited RANTES production in response to IL-1. However, the change of Syk expression did not affect RANTES production by TNF-α stimulation. We concluded that Syk is required for the IL-1-induced chemokine production through the association with TRAF-6 in fibroblasts of nasal polyps.
Structural Effects of Framework Mutations on a Humanized Anti-Lysozyme Antibody
Authors: Holmes Margaret A. , Buss Timothy N. , Foote Jefferson 
Published: April 2014

Abstract
A humanized version of the mouse anti-lysozyme Ab D1.3 was previously constructed as an Fv fragment and its structure was crystallographically determined in the free form and in complex with lysozyme. Here we report five new crystal structures of single-amino acid substitution mutants of the humanized Fv fragment, four of which were determined as Fv-lysozyme complexes. The crystals were isomorphous with the parent forms, and were refined to free R values of 28–31% at resolutions of 2.7–2.9 Å. Residue 27 in other Abs has been implicated in stabilizing the conformation of the first complementarity-determining region (CDR) of the H chain, residues 31–35. We find that a Phe-to-Ser mutation at 27 alters the conformation of immediately adjacent residues, but this change is only weakly transmitted to Ag binding residues in the nearby CDR. Residue 71 of the H chain has been proposed to control the relative disposition of H chain CDRs 1 and 2, based on the bulk of its side chain. However, in structures we determined with Val, Ala, or Arg substituted in place of Lys at position 71, no significant change in the conformation of CDRs 1 and 2 was observed.
The Smad3 Protein Is Involved in TGF-β Inhibition of Class II Transactivator and Class II MHC Expression
Authors: Dong Yuanshu , Tang Liping , Letterio John J. , Benveniste Etty N. 
Published: April 2014

AbstractTGF-β is a immunoregulatory cytokine that inhibits class II MHC expression in a variety of cell types. Previous studies have shown that the class II MHC transactivator (CIITA), a master regulator that controls class II MHC expression, is targeted by TGF-β for repression of IFN-γ-induced class II MHC expression in astrocytes. The mechanism(s) underlying the TGF-β inhibitory effect is not understood. In this study, we demonstrate that TGF-β inhibition of CIITA expression occurs at the transcriptional level, and that both constitutive and IFN-γ-induced human CIITA type IV promoter activity is inhibited by TGF-β. TGF-β does not affect the signaling events that mediate IFN-γ activation of CIITA expression; i.e, TGF-β does not inhibit IFN-γ-induced STAT-1α phosphorylation and/or DNA binding ability, nor is IFN-γ induction of IFN regulatory factor affected. The inhibitory effect of TGF-β on the type IV CIITA promoter is mediated through a promoter region within 80 bp from the transcription start site. Elimination of TGF-β inhibition of class II MHC and CIITA expression in Smad3-deficient astrocytes, as well as restoration of the inhibitory effect by overexpression of the Smad3 protein, demonstrates that Smad3 is essential in mediating TGF-β inhibition of CIITA and class II MHC expression.
Induction of Germline Transcription in the Human TCRγ Locus by STAT5
Authors: Lee Hai-Chon , Ye Sang-Kyu , Honjo Tasuku , Ikuta Koichi 
Published: April 2014

Abstract
TCR and Ig genes are assembled by V(D)J recombination during lymphocyte development. The enhancer and the germline promoter control the accessibility of each locus for the common recombinase activity. In the mouse TCRγ locus, STAT5 proteins activated by the IL-7R interact with consensus motifs in 5′ regions of Jγ segments and induce germline transcription. To evaluate the role of STAT5 in controlling the accessibility of the TCRγ locus, we characterized the germline transcription of human TCRγ genes and compared it with mouse. We first demonstrated that Jγ-Cγ germline transcripts are induced in a cytokine-dependent human erythroleukemia cell line. STAT consensus motifs are present in 5′ regions of Jγ1.1 and Jγ2.1 gene segments, and activated STAT5 binds to these motifs. By using a reporter assay, we showed that the Jγ1.1 germline promoter is transactivated by STAT5 and that mutations in any of the two STAT motifs abrogate this activity. Thus, this study demonstrates that STAT5 induces germline transcription in the TCRγ locus of both mouse and human and suggests the possibility that this mechanism may play an essential role in controlling the TCRγ locus accessibility. In addition, STAT motifs are conserved among 5′ Jγ germline promoters, 3′ enhancers, and a locus control region-like element, HsA, in both mouse and human TCRγ loci, indicating the possibility that IL-7R/STAT5 signaling probably controls the locus-wide accessibility through these elements.
Decreased Frequency of Somatic Hypermutation and Impaired Affinity Maturation but Intact Germinal Center Formation in Mice Expressing Antisense RNA to DNA Polymerase ζ
Authors: Diaz Marilyn , Verkoczy Laurent K. , Flajnik Martin F. , R. Klinman Norman 
Published: April 2014

Abstract
To examine a role of DNA polymerase ζ in somatic hypermutation, we generated transgenic mice that express antisense RNA to a portion of mouse REV3, the gene encoding this polymerase. These mice express high levels of antisense RNA, significantly reducing the levels of endogenous mouse REV3 transcript. Following immunization to a hapten-protein complex, transgenic mice mounted vigorous Ab responses, accomplished the switch to IgG, and formed numerous germinal centers. However, in most transgenic animals, the generation of high affinity Abs was delayed. In addition, accumulation of somatic mutations in the VH genes of memory B cells from transgenic mice was decreased, particularly among those that generate amino acid replacements that enhance affinity of the B cell receptor to the hapten. These data implicate DNA polymerase ζ, a nonreplicative polymerase, in the process of affinity maturation, possibly through a role in somatic hypermutation, clonal selection, or both.
Unstimulated Human CD4 Lymphocytes Express a Cytoplasmic Immature Form of the Common Cytokine Receptor γ-Chain
Authors: Bani Lynda , Pasquier Virginie , Kryworuchko Marko , Salamero Jean , Thèze Jacques 
Published: April 2014

AbstractAs a component of various cytokine receptors, common cytokine receptor γ-chain (γc) is essential in the development of the immune system and plays an important role in different stages of inflammatory and immune responses. Here we establish that resting CD4 T cells and the Jurkat CD4 T cell line do not express the mature form of γc (64 kDa) recognized by mAb Tugh4. However, these cells constitutively transcribe the corresponding γc gene. This apparent paradox was solved by the demonstration that polyclonal anti-γc Abs detected endoglycosidase-H-sensitive immature forms of γc (54–58 kDa) expressed by quiescent CD4 T lymphocytes and Jurkat cells. Immature γc is characterized as an intracellular component localized in the endoplasmic reticulum. Pulse-chase analysis shows that the immature γc is rapidly degraded after synthesis. After activation of CD4 T lymphocytes, and as seen in the CD4 T cell line Kit 225, the endoglycosidase-H-resistant mature form of γc is detectable at the cell surface and in the endosomal compartment. For the first time, our results demonstrate that a cytokine receptor chain may be constitutively produced as an immature form. Furthermore, this supports the notion that expression of the functional form of γc may require intracellular interactions with lineage- or subset-specific molecular partners.
A Distinct Pathway of Cell-Mediated Apoptosis Initiated by Granulysin
Authors: Kaspar Allan A. , Okada Satoshi , Kumar Jayant , Poulain Francis R. , Drouvalakis Katerina A. , Kelekar Ameeta , Hanson Dennis A. , Kluck Ruth M. , Hitoshi Yasumichi , Johnson Daniel E. , Froelich Christopher J. , Thompson Craig B. , Newmeyer Donald D. , Anel Alberto , Clayberger Carol , Krensky Alan M. 
Published: April 2014

Abstract
Granulysin is an antimicrobial and tumoricidal molecule expressed in granules of CTL and NK cells. In this study, we show that granulysin damages cell membranes based upon negative charge, disrupts the transmembrane potential (Δψ) in mitochondria, and causes release of cytochrome c. Granulysin-induced apoptosis is blocked in cells overexpressing Bcl-2. Despite the release of cytochrome c, procaspase 9 is not processed. Nevertheless, activation of caspase 3 is observed in granulysin-treated cells, suggesting that granulysin activates a novel pathway of CTL- and NK cell-mediated death distinct from granzyme- and death receptor-induced apoptosis.
Protection Against Murine Listeriosis by Oral Vaccination with Recombinant Salmonella Expressing Hybrid Yersinia Type III Proteins
Authors: Rüssmann Holger , Igwe Emeka I. , Sauer Jeannette , Hardt Wolf-Dietrich , Bubert Andreas , Geginat Gernot 
Published: April 2014

Abstract
In the present study, we have investigated the possibility to engage the Yersinia outer protein E (YopE) as a carrier molecule for heterologous Ag delivery by the type III secretion system of Salmonella typhimurium. Defined secretion and translocation domains of YopE were fused to the immunodominant T cell Ags listeriolysin O and p60 of Listeria monocytogenes. In vitro experiments showed that S. typhimurium allows secretion and translocation of large hybrid YopE proteins in a type III-dependent fashion. Translocation and cytosolic delivery of these chimeric proteins into host cells, but not secretion into endosomal compartments, led to efficient MHC class I-restricted Ag presentation of listerial nonamer peptides. Mice orally vaccinated with a single dose of attenuated S. typhimurium expressing translocated hybrid YopE proteins revealed high numbers of IFN-γ-producing cells reactive with listeriolysin O 91–99 or p60 217–225, respectively. This CD8 T cell response protected mice against a challenge with L. monocytogenes. In conclusion, these findings suggest that YopE is a versatile carrier molecule for type III-mediated foreign Ag delivery by Salmonella vaccine strains.
Structural Features of Nonpeptide Prenyl Pyrophosphates That Determine Their Antigenicity for Human γδ T Cells
Authors: Morita Craig T. , Lee Hoi K. , Wang Hong , Li Hongmin , Mariuzza Roy A. , Tanaka Yoshimasa 
Published: April 2014

Abstract
Human Vγ2Vδ2+ T cells proliferate in vivo during many microbial infections. We have found that Vγ2Vδ2+ T cells recognize nonpeptide prenyl pyrophosphates and alkylamines. We now have defined structural features that determine the antigenicity of prenyl pyrophosphates by testing synthetic analogs for bioactivity. We find that the carbon chain closest to the pyrophosphate moiety plays the major role in determining bioactivity. Changes in this area, such as the loss of a double bond, abrogated bioactivity. The loss of a phosphate from the pyrophosphate moiety also decreased antigenicity 100- to 200-fold. However, nucleotide monophosphates could be added with minimal changes in bioactivity. Longer prenyl pyrophosphates also retained bioactivity. Despite differences in CDR3 sequence, Vγ2Vδ2+ clones and a transfectant responded similarly. Ag docking into a Vγ2Vδ2 TCR model reveals a potential binding site in germline regions of the Vγ2Jγ1.2 CDR3 and Vδ2 CDR2 loops. Thus, Vγ2Vδ2+ T cells recognize a core carbon chain and pyrophosphate moiety. This recognition is relatively unaffected by additions at distal positions to the core Ag unit.
IL-8 Production in Human Lung Fibroblasts and Epithelial Cells Activated by the Pseudomonas Autoinducer N-3-Oxododecanoyl Homoserine Lactone Is Transcriptionally Regulated by NF-κB and Activator Protein-2
Authors: Smith Roger S. , Fedyk Eric R. , Springer T. A. , Mukaida N. , Iglewski Barbara H. , Phipps Richard P. 
Published: April 2014

Abstract
The destructive pulmonary inflammation associated with Pseudomonas aeruginosa colonization is caused, in part, by the production of the chemokine IL-8, which recruits neutrophils into the lung. The Pseudomonas autoinducer, N-3-oxododecanoyl homoserine lactone (3-O-C12-HSL), is a small lipid-soluble molecule that is essential in the regulation of many P. aeruginosa virulence factors, but little is known about how it affects eukaryotic cells. In this report we demonstrate that 3-O-C12-HSL is a potent stimulator of both IL-8 mRNA and protein from human fibroblasts and epithelial cells in vitro. The IL-8 produced from these 3-O-C12-HSL-stimulated cells was found to be functionally active by inducing the chemotaxis of neutrophils. To determine a mechanism for this IL-8 induction, deletion constructs of the IL-8 promoter were examined. It was found that the DNA region between nucleotides −1481 and −546 and the transcription factor NF-κB were essential for the maximal induction of IL-8 by 3-O-C12-HSL. This was confirmed by EMSAs, where 3-O-C12-HSL induced a shift with both AP-2 and NF-κB consensus DNA. The activation of NF-κB and subsequent production of IL-8 were found to be regulated by a mitogen-activated protein kinase pathway. These findings support the concept that the severe lung damage that accompanies P. aeruginosa infections is caused by an exuberant neutrophil response stimulated by 3-O-C12-HSL-induced IL-8. Understanding the mechanisms of 3-O-C12-HSL activation of lung structural cells may provide a means to help control lung damage during infections with P. aeruginosa.
IFN-γ-Independent Autocrine Cytokine Regulatory Mechanism in Reprogramming of Macrophage Responses to Bacterial Lipopolysaccharide
Authors: Brewington Ryan , Chatterji Manjil , Zoubine Mikhail , Miranda Roberto N. , Norimatsu Mari , Shnyra Alex 
Published: April 2014

Abstract
Macrophages are now well recognized to have a critical role in both innate and acquired immunity. The sentinel macrophage function is highly regulated and serves to allow for intrinsic plasticity of the innate immune responses to potential environmental signals. However, the mechanisms underlying the dynamic properties of the cellular arm of innate immunity are poorly understood. Therefore, we have conducted a series of in vitro studies to evaluate the contribution of immunoregulatory cytokines, such as IFN-γ, IL-10, and IL-12, in modulation of macrophage responses. We found that macrophages from IFN-γ knockout (IFN-γ−/−) mice exhibit only marginal LPS-induced TNF-α, IL-12, and NO responses, all of which can be fully restored in the presence of rIFN-γ. Pretreatment with substimulatory LPS concentrations led to reprogramming of IFN-γ−/− macrophage responses in a dose-dependent manner that manifested by an increased TNF-α and IL-12, but not NO, production upon the subsequent LPS challenge. These reprogramming effects were substantially attenuated and profoundly enhanced in macrophages from IL-12−/− and IL-10−/− mice, respectively, as compared with those modulated in macrophages from the congenic wild-type mice. LPS-dependent reprogramming was also fully reproduced in macrophages isolated from SCID mice after immunodepletion of NK cells. Our data strongly imply that cytokine (TNF-α and IL-12), but not NO, responses in macrophages may, at least in part, be governed by an autocrine IFN-γ-independent regulatory mechanism reciprocally controlled by IL-10 and IL-12. This mechanism may serve as an alternative/coherent pathway to the canonical IFN-γ-dependent induction of antimicrobial and tumoricidal activity in macrophages.
Impaired Mucosal Immunity in L-Selectin-Deficient Mice Orally Immunized with aSalmonellaVaccine Vector
Authors: Pascual David W. , White Michelle D. , Larson Trina , Walters Nancy 
Published: April 2014

AbstractLymphocyte trafficking in the gastrointestinal tract is primarily mediated by interactions with the mucosal addressin cell adhesion molecule 1 and its lymphocyte ligand, α4β7, and partly by L-selectin (L-Sel) interactions with peripheral node addressin coexpressed on some mucosal addressin cell adhesion molecule 1. We inquired whether intestinal responses in mice lacking L-Sel would be enhanced. L-Sel-deficient (L-Sel−/−) mice were orally immunized with either Salmonella vaccine vector or Salmonella vector-expressing colonization factor Ag I (CFA/I) from enterotoxigenic Escherichia coli. In L-Sel−/− mice, mucosal IgA anti-CFA/I fimbrial responses were greatly reduced, and systemic IgG2a anti-CFA/I fimbrial responses were 26-fold greater compared with C57BL/6 (L-Sel+/+) mice. L-Sel−/− Peyer’s patch (PP) CD4+ Th cells revealed IFN-γ-dominated responses and an unprecedented absence of IL-4, whereas the expected mixed Th cell phenotype developed in L-Sel+/+ mice. PP CD4+ Th cell anti-Salmonella responses were nearly nonexistent in L-Sel−/− mice immunized with either Salmonella vaccine. Splenic CD4+ Th cell anti-Salmonella responses were reduced but did show cytokine production in Ag restimulation assays. Increased colonization of PP and spleen was noted only with the Salmonella vector in L-Sel−/− mice, resulting in increased splenomegaly, suggesting that the Salmonella-CFA/I vaccine was not as infectious or that the presence of the fimbriae improved clearance, possibly because of reduced neutrophil recruitment. However, sufficient anti-Salmonella immunity was induced, because Salmonella vector-immunized L-Sel−/− mice showed complete protection against wild-type Salmonella challenge, unlike L-Sel+/+ mice. This evidence shows that L-Sel is important for development of mucosal immunity, and absence of L-Sel is protective against salmonellosis.
Activation of Toll-Like Receptor-2 by Glycosylphosphatidylinositol Anchors from a Protozoan Parasite
Authors: Campos Marco A. S. , Almeida Igor C. , Takeuchi Osamu , Akira Shizuo , Valente Eneida P. , Procópio Daniela O. , Travassos Luiz R. , Smith Jason A. , Golenbock Douglas T. , Gazzinelli Ricardo T. 
Published: April 2014

AbstractGlycosylphosphatidylinositol (GPI) anchors and glycoinositolphospholipids (GIPLs) from parasitic protozoa have been shown to exert a wide variety of effects on cells of the host innate immune system. However, the receptor(s) that are triggered by these protozoan glycolipids has not been identified. Here we present evidence that Trypanosoma cruzi-derived GPI anchors and GIPLs trigger CD25 expression on Chinese hamster ovary-K1 cells transfected with CD14 and Toll-like receptor-2 (TLR-2), but not wild-type (TLR-2-deficient) Chinese hamster ovary cells. The protozoan-derived GPI anchors and GIPLs containing alkylacylglycerol and saturated fatty acid chains or ceramide were found to be active in a concentration range of 100 nM to 1 μM. More importantly, the GPI anchors purified from T. cruzi trypomastigotes, which contain a longer glycan core and unsaturated fatty acids in the sn-2 position of the alkylacylglycerolipid component, triggered TLR-2 at subnanomolar concentrations. We performed experiments with macrophages from TLR-2 knockout and TLR-4 knockout mice, and found that TLR-2 expression appears to be essential for induction of IL-12, TNF-α, and NO by GPI anchors derived from T. cruzi trypomastigotes. Thus, highly purified GPI anchors from T. cruzi parasites are potent activators of TLR-2 from both mouse and human origin. The activation of TLR-2 may initiate host innate defense mechanisms and inflammatory response during protozoan infection, and may provide new strategies for immune intervention during protozoan infections.
Expression of Active Protein Kinase B in T Cells Perturbs Both T and B Cell Homeostasis and Promotes Inflammation
Authors: Parsons Michael J. , Jones Russell G. , Tsao Ming-Sound , Odermatt Bernard , Ohashi Pamela S. , Woodgett James R. 
Published: April 2014

AbstractThe molecular mechanisms that contribute to autoimmunity remain poorly defined. While inflammation is considered to be one of the major checkpoints in autoimmune disease progression, very little is known about the initiating events that trigger inflammation. We have studied transgenic mice expressing the prosurvival molecule protein kinase B/Akt under control of a T cell-specific CD2 promoter. In this study, we demonstrate that aged mice develop lymphadenopathy and splenomegaly that result from an accumulation of CD4, CD8, and unexpectedly B cells. An increased proportion of T cells express activation markers, while T cell proliferative responses remain normal. B cells are hyperproliferative in response to anti-IgM F(ab′)2 and anti-CD40, and increased IgA and IgG2a were found in the sera. In addition, a profound multiorgan lymphocytic infiltration is observed, and T cells from these mice display a defect in Fas-mediated apoptosis, which may be the mechanism underlying this phenotype. Therefore, T cell expression of active protein kinase B can alter T cell homeostasis, indirectly influence B cell homeostasis, and promote inflammation in vivo.
Role of Effector Cell-Derived IL-4, IL-5, and Perforin in Early and Late Stages of Type 2 CD8 Effector Cell-Mediated Tumor Rejection
Authors: Dobrzanski Mark J. , Reome Joyce B. , Dutton Richard W. 
Published: April 2014

AbstractType 2 CD8 T cells (Tc2) secrete IL-4 and IL-5 and display perforin-dependent cytolysis in vitro. Using an OVA-transfected B16-melanoma model, we show that tumor-reactive Tc2 effector cells accumulated at the tumor site and induced tumor regression that enhanced survival in mice with pulmonary tumors. Transfer of perforin-deficient Tc2 cells generated from perforin gene knockout mice showed no differences in therapeutic efficiency when compared with wild-type Tc2 cells. In contrast, Tc2 cells derived from select cytokine gene-deficient mice showed that therapeutic effects were dependent on effector cell-derived IL-4 and IL-5 that led to a local elevation in lung-derived chemoattractants and accumulation of activated host-derived CD8/CD44high, CD4/CD44high, and OVA-specific tetramer-positive CD8 cells in vivo. Host-derived T and non-T immune cells increased in the lung over time and correlated with an elevated production of type 1-related chemokines. Conversely, donor Tc2 cell numbers markedly diminished at later times, suggesting that prolonged therapeutic responses were due to host-derived mechanisms. Moreover, type 1 host responses were detectable with increased levels of IFN-γ production by lung-derived CD4 and CD8 T cells from surviving Tc2-treated mice. Transfer of Tc2 cells into IFN-γ-deficient tumor-bearing mice was markedly less effective then into wild-type mice, suggesting that host-derived IFN-γ-dependent mechanisms play a role in Tc2-mediated antitumor responses.