bluuebunny/crossref_metadata_2025_split huggingface dataset:
STAT6 Mediates Eotaxin-1 Expression in IL-4 or TNF-α-Induced Fibroblasts
Authors: Hoeck Jutta , Woisetschläger Maximilian 
Published: April 2014

AbstractEosinophils are attracted to sites of allergic inflammation by a number of chemoattractants including eotaxin-1. This chemokine can be secreted from epithelial cells and fibroblasts after IL-4 and TNF-α stimulation in a synergistic fashion. TNF-α activated gene expression at the transcriptional level in a STAT6-dependent manner, because: 1) eotaxin-1 promoter luciferase constructs were TNF-α inducible in STAT6-defective HEK293 cells only on cotransfection of STAT6 expression vector, an effect that was partially mediated by activation-induced binding of NF-κB proteins to a composite STAT6/NF-κB element; 2) reporter constructs defective in STAT6 DNA binding did not respond to TNF-α stimulation; 3) eotaxin-1 protein secretion was detected only in STAT6-transfected HEK293 cell supernatants on TNF-α treatment; and 4) a trans-dominant negative STAT6 protein inhibited TNF-α-induced eotaxin-1 secretion in primary fibroblasts. TNF-α inducibility of the IL-8 and monocyte chemoattractant protein-1 genes was not dependent on STAT6 expression in the same experimental systems. The inducing effect of IL-4 and IL-13 was also mediated by STAT6. The synergistic effect of IL-4 and TNF-α observed at the RNA and the protein level was not seen at the promoter level. The data demonstrate that both IL-4 and TNF-α induce eotaxin-1 expression at the level of transcription via a STAT6-mediated pathway.
Cysteinylation of MHC Class II Ligands: Peptide Endocytosis and Reduction Within APC Influences T Cell Recognition
Authors: Haque M. Azizul , Hawes John W. , Blum Janice S. 
Published: April 2014

AbstractPeptides bind cell surface MHC class II proteins to yield complexes capable of activating CD4+ T cells. By contrast, protein Ags require internalization and processing by APC before functional presentation. Here, T cell recognition of a short peptide in the context of class II proteins occurred only after delivery of this ligand to mature endosomal/lysosomal compartments within APC. Functional and biochemical studies revealed that a central cysteine within the peptide was cysteinylated, perturbing T cell recognition of this epitope. Internalization and processing of the modified epitope by APC, was required to restore T cell recognition. Peptide cysteinylation and reduction could occur rapidly and reversibly before MHC binding. Cysteinylation did not disrupt peptide binding to class II molecules, rather the modified peptide displayed an enhanced affinity for MHC at neutral pH. However, once the peptide was bound to class II proteins, oxidation or reduction of cysteine residues was severely limited. Cysteinylation has been shown to radically influence T cell responses to MHC class I ligands. The ability of professional APC to reductively cleave this peptide modification presumably evolved to circumvent a similar problem in MHC class II ligand recognition.
Identification of a Novel Lipopolysaccharide-Inducible Gene with Key Features of Both a Kinase Anchor Proteins and chs1/beige Proteins
Authors: Wang Jia-Wang , Howson Julie , Haller Edward , Kerr William G. 
Published: April 2014

Abstract
Mutations in chs1/beige result in a deficiency in intracellular transport of vesicles that leads to a generalized immunodeficiency in mice and humans. The function of NK cells, CTL, and granulocytes is impaired by these mutations, indicating that polarized trafficking of vesicles is controlled by CHS1/beige proteins. However, a molecular explanation for this defect has not been identified. Here we describe a novel gene with orthologues in mice, humans, and flies that contains key features of both chs1/beige and A kinase anchor genes. We designate this novel gene lba for LPS-responsive, beige-like anchor gene. Expression of lba is induced after LPS stimulation of B cells and macrophages. In addition, lba is expressed in many other tissues in the body and has three distinct mRNA isoforms that are differentially expressed in various tissues. Strikingly, LBA-green-fluorescent protein (GFP) fusion proteins are localized to vesicles after LPS stimulation. Confocal microscopy indicates this protein is colocalized with the trans-Golgi complex and some lysosomes. Further analysis by immunoelectron microscopy demonstrates that LBA-GFP fusion protein can localize to endoplasmic reticulum, plasma membrane, and endocytosis vesicles in addition to the trans-Golgi complex and lysosomes. We hypothesize that LBA/CHS1/BG proteins function in polarized vesicle trafficking by guiding intracellular vesicles to activated receptor complexes and thus facilitate polarized secretion and/or membrane deposition of immune effector molecules.
Diversity of Epitope and Cytokine Profiles for Primary and Secondary Influenza A Virus-Specific CD8+ T Cell Responses
Authors: Belz Gabrielle T. , Xie Weidong , Doherty Peter C. 
Published: April 2014

Abstract
Screening with the flow cytometric IFN-γ assay has led to the identification of a new immunogenic peptide (SSYRRVPGI) from the influenza PB1 polymerase (PB1703–711) and a mimotope (ISPLMVAYM) from the PB2 polymerase (PB2198–206). CD8+ T cells specific for KbPB1703 make both IFN-γ and TNF-α following stimulation with both peptides. The CD8+ KbPB1703+ population kills PB2198-pulsed targets, but cell lines stimulated with PB2198 neither bind the KbPB1703 tetramer nor become CTL. This CD8+KbPB1703+ population is prominent in the primary response to an H3N2 virus, although it is much less obvious following secondary challenge of H1N1-primed mice. Even so, we can now account for &gt;40% of the CD8+ T cells in a primary influenza pneumonia and &gt;85% of those present after H3N2 → H1N1 challenge. Profiles of IFN-γ and TNF-α staining following in vitro stimulation have been traced for the four most prominent influenza peptides through primary and secondary responses into long-term memory. The DbNP366 epitope that is immunodominant after the H3N2 → H1N1 challenge shows the lowest frequencies of CD8+ IFN-γ+TNF-α+ cells for &gt;6 wk, and the intensity of IFN-γ staining is also low for the first 3 wk. By 11 wk, however, the IFN-γ/TNF-α profiles look to be similar for all four epitopes. At least by the criterion of cytokine production, there is considerable epitope-related functional diversity in the influenza virus-specific CD8+ T cell response. The results for the KbPB1703 epitope and the PB2198 mimotope also provide a cautionary tale for those using the cytokine staining approach to identity antigenic peptides.
An Increase in Circulating Mast Cell Colony-Forming Cells in Asthma
Authors: Mwamtemi Hadija Hemed , Koike Kenichi , Kinoshita Tatsuya , Ito Susumu , Ishida Shuichi , Nakazawa Yozo , Kurokawa Yumi , Shinozaki Koji , Sakashita Kazuo , Takeuchi Kouichi , Shiohara Masaaki , Kamijo Takehiko , Yasui Yozo , Ishiguro Akira , Kawano Yoshifumi , Kitano Kiyoshi , Miyazaki Hiroshi , Kato Takashi , Sakuma Shozo , Komiyama Atsushi 
Published: April 2014

Abstract
We compared a potential to generate mast cells among various sources of CD34+ peripheral blood (PB) cells in the presence of stem cell factor (SCF) with or without thrombopoietin (TPO), using a serum-deprived liquid culture system. From the time course of relative numbers of tryptase-positive and chymase-positive cells in the cultured cells grown by CD34+ PB cells of nonasthmatic healthy individuals treated with G-CSF, TPO appears to potentiate the SCF-dependent growth of mast cells without influencing the differentiation into mast cell lineage. CD34+ PB cells from asthmatic patients in a stable condition generated significantly more mast cells under stimulation with SCF alone or SCF+TPO at 6 wk of culture than did steady-state CD34+ PB cells of normal controls. Single-cell culture studies showed a substantial difference in the number of SCF-responsive or SCF+TPO-responsive mast cell progenitors in CD34+ PB cells between the two groups. In the presence of TPO, CD34+ PB cells from asthmatic children could respond to a suboptimal concentration of SCF to a greater extent, compared with the values obtained by those of normal controls. Six-week cultured mast cells of asthmatic subjects had maturation properties (intracellular histamine content and tryptase/chymase enzymatic activities) similar to those derived from mobilized CD34+ PB cells of nonasthmatic subjects. An increase in a potential of circulating hemopoietic progenitors to differentiate into mast cell lineage may contribute to the recruitment of mast cells toward sites of asthmatic mucosal inflammation.
Macrophages Transfected with Adenovirus to Express IL-4 Reduce Inflammation in Experimental Glomerulonephritis
Authors: Kluth David C. , Ainslie Clare V. , Pearce Wayne P. , Finlay Sian , Clarke Daniel , Anegon Ignacio , Rees Andrew J. 
Published: April 2014

Abstract
Nephrotoxic nephritis (NTN) is characterized by acute macrophage-dependent inflammation and serves as a model of human glomerulonephritis. In this study we have transfected rat macrophages with recombinant adenovirus expressing IL-4 (Ad-IL4) and demonstrated that these transfected macrophages develop fixed properties as a result of transfection, as shown by reduced NO production in response to IFN-γ and TNF. Ad-IL4-transfected macrophages localized with enhanced efficiency to inflamed glomeruli after renal artery injection in rats with NTN compared with adenovirus expressing β-galactosidase (Ad-βgal)-transfected macrophages and produced elevated levels of the cytokine in glomeruli in vivo for up to 4 days. The delivery of IL-4-expressing macrophages produced a marked reduction in the severity of albuminuria (day 2 albuminuria, 61 ± 15 mg/24 h) compared with unmodified NTN (day 2 albuminuria, 286 ± 40 mg/24 h; p &lt; 0.01), and this was matched by a reduction in the number of ED1-positive macrophages infiltrating the glomeruli. Interestingly, the injection of IL-4-expressing macrophages into single kidney produced a marked reduction in the numbers of ED1-positive macrophages in the contralateral noninjected kidney, an effect that could not be mimicked by systemic delivery of IL-4-expressing macrophages. This implies that the presence of IL-4-expressing macrophages in a single kidney can alter the systemic development of the inflammatory response. Macrophage transfection and delivery provide a valuable system to study and modulate inflammatory disease and highlight the feasibility of macrophage-based gene therapy.
Nonphlogistic Clearance of Late Apoptotic Neutrophils by Macrophages: Efficient Phagocytosis Independent of β2 Integrins
Authors: Ren Yi , Stuart Lynda , Lindberg Frederik P. , Rosenkranz Alexander R. , Chen Yongmei , Mayadas Tanya N. , Savill John 
Published: April 2014

Abstract
Neutrophils undergo constitutive death by apoptosis, leading to safe nonphlogistic phagocytosis and clearance by macrophages. Recent work has shown that before secondary necrosis, neutrophils exhibiting classical features of apoptosis can progress to a morphologically defined late apoptotic state. However, whether such neutrophils could be safely cleared was unknown. We now report that human late apoptotic neutrophils could be purified from cultured neutrophil populations undergoing constitutive death and were subsequently ingested by human monocyte-derived macrophages by serum-independent mechanisms that did not trigger the release of IL-8 or TNF-α. Such ingestion was specifically inhibited by Abs to thrombospondin-1 and the αvβ3 vitronectin receptor. Murine bone marrow-derived macrophage phagocytosis of late and early apoptotic neutrophils occurred by similar mechanisms, proceeding with the same efficiency as that observed for wild-type controls when macrophages from αm−/− or β2−/− mice were used. We conclude that specific nonphlogistic, β2 integrin-independent mechanisms involving thrombospondin-1 and αvβ3 allow macrophages to ingest late apoptotic neutrophils without eliciting inflammatory cytokine secretion.
Specific Immunotherapy by Genetically Engineered APCs: The “Guided Missile” Strategy
Authors: Wu Bo , Wu Jian-Ming , Miagkov Alexei , Adams Robert N. , Levitsky Hyam I. , Drachman Daniel B. 
Published: April 2014

Abstract
We tested the hypothesis that APCs genetically engineered to present an Ag and to express Fas ligand (FasL) simultaneously can target and eliminate Ag-specific T cells. Transgenic T cells specific for influenza hemagglutinin (HA) were used as targets. We prepared recombinant vaccinia virus vectors (VVV) to transfer the gene constructs individually or simultaneously into APCs. We prevented unwanted viral replication by attenuating the VVVs with psoralen-UV light treatment. For presentation of the HA Ag, APCs were transduced with cDNA for HA flanked by sequences of the lysosome-associated membrane protein that direct efficient processing and presentation of the Ag by APCs. As a “warhead” for the APCs, we transduced them with the gene for FasL, which induces apoptosis of Fas-expressing activated T cells. To protect the transduced APCs from self-destruction by FasL, we transferred cDNA for a truncated form of Fas-associated death domain, which inhibits Fas-mediated cell death. Our results show that the engineered APCs effectively expressed the genes of interest. APCs transduced with VVV carrying all three gene constructs specifically killed HA-transgenic T cells in culture. Coculture with T cells specific for an unrelated Ag (OVA) had no significant effect. Our in vitro findings show that APCs can be genetically engineered to target and kill Ag-specific T cells and represent a promising novel strategy for the specific treatment of autoimmune diseases.
Reactivity of Anti-Proliferating Cell Nuclear Antigen (PCNA) Murine Monoclonal Antibodies and Human Autoantibodies to the PCNA Multiprotein Complexes Involved in Cell Proliferation
Authors: Takasaki Yoshinari , Kogure Toshiaki , Takeuchi Ken , Kaneda Kazuhiko , Yano Tetsuro , Hirokawa Kaoru , Hirose Sachiko , Shirai Toshikazu , Hashimoto Hiroshi 
Published: April 2014

Abstract
Proliferating cell nuclear Ag (PCNA) occurs as a component of multiprotein complexes during cell proliferation. We found the complexes to react with murine anti-PCNA mAbs, but not with anti-PCNA Abs in lupus sera. The complexes were purified from rabbit thymus extract by affinity chromatography using anti-PCNA mAbs (TOB7, TO17, and TO30) and analyzed by ELISA, immunoprecipitation, immunoblotting, and HPLC gel filtration. That PCNA was complexed with other proteins was demonstrated by its copurification with a group of proteins excluded by an HPLC G3000 SW column. Although immunoblot analysis showed the mAbs to react exclusively with the 34-kDa PCNA polypeptide, they nonetheless immunoprecipitated the same group of proteins, confirming the interaction of the isolated PCNA with other proteins. Anti-PCNA sera, including AK, which reacts with biologically functional sites on PCNA, did not react with complexed PCNA, but did react with it once it was dissociated from the complexes. PCNA complexes in turn reacted with murine anti-DNA mAbs, as well as with Abs against p21, replication protein A, DNA helicase II, cyclin-dependent kinases 4 and 5, and topoisomerase I. These findings suggest that the PCNA complexes purified using anti-PCNA mAbs comprise the “protein machinery” for DNA replication and cell cycle regulation. They also suggest that anti-PCNA mAbs are useful tools with which to characterize the protein-protein interactions within PCNA complexes, as well as the autoimmune responses to proteins interacting with PCNA, which may shed light on the mechanisms of autoantibody production in lupus patients.
Cutting Edge: Evidence for a Signaling Partnership Between Urokinase Receptors (CD87) and L-Selectin (CD62L) in Human Polymorphonuclear Neutrophils
Authors: Sitrin Robert G. , Pan Pauline M. , Blackwood R. Alexander , Huang Jibiao , Petty Howard R. 
Published: April 2014

AbstractLeukocyte urokinase plasminogen activator receptors (uPARs) cluster at adhesion interfaces and at migratory fronts where they participate in adhesion, chemotaxis, and proteolysis. uPAR aggregation triggers activation signaling even though this glycolipid-anchored protein must associate with membrane-spanning proteins to access the cell interior. This study demonstrates a novel partnership between uPAR and L-selectin in human polymorphonuclear neutrophils. Fluorescence resonance energy transfer demonstrated a direct physical association between uPAR and L-selectin. To examine the role of L-selectin in uPAR-mediated signaling, uPAR was cross-linked and intracellular Ca2+ concentrations were measured by spectrofluorometry. A mAb reactive against the carbohydrate binding domain (CBD) of L-selectin substantially inhibited uPAR-mediated Ca2+ mobilization, whereas mAbs against the β2 integrin complement receptor 3 (CR3), another uPAR-binding adhesion protein, had no effect. Similarly, fucoidan, a sulfated polysaccharide that binds to L-selectin CBD, inhibited the Ca2+ signal. We conclude that uPAR associates with the CBD region of L-selectin to form a functional signaling complex.
Suppression of IgE Responses in CD23-Transgenic Animals Is Due to Expression of CD23 on Nonlymphoid Cells
Authors: Payet-Jamroz Margaret , Helm Shirley L. T. , Wu Jiuhua , Kilmon Michelle , Fakher Mohamed , Basalp Aynur , Tew John G. , Szakal Andras K. , Noben-Trauth Nancy , Conrad Daniel H. 
Published: April 2014

AbstractSerum IgE is suppressed in CD23-transgenic (Tg) mice where B cells and some T cells express high levels of CD23, suggesting that CD23 on B and T cells may cause this suppression. However, when Tg B lymphocytes were compared with controls in B cell proliferation and IgE synthesis assays, the two were indistinguishable. Similarly, studies of lymphokine production suggested that T cell function in the Tg animals was normal. However, adoptive transfer studies indicated that suppression was seen when normal lymphocytes were used to reconstitute Tg mice, whereas reconstitution of controls with Tg lymphocytes resulted in normal IgE responses, suggesting that critical CD23-bearing cells are irradiation-resistant, nonlymphoid cells. Follicular dendritic cells (FDC) are irradiation resistant, express surface CD23, and deliver iccosomal Ag to B cells, prompting us to reason that Tg FDC may be a critical cell. High levels of transgene expression were observed in germinal centers rich in FDC and B cells, and IgE production was inhibited when Tg FDCs were cultured with normal B cells. In short, suppressed IgE production in CD23-Tg mice appears to be associated with a population of radioresistant nonlymphoid cells. FDCs that interface with B cells in the germinal center are a candidate for explaining this CD23-mediated IgE suppression.
Coregulation of CXC Chemokine Receptor and CD4 Expression on T Lymphocytes During Allogeneic Activation
Authors: Ebert Lisa M. , McColl Shaun R. 
Published: April 2014

Abstract
Upon activation, naive T cells alter their migratory patterns, acquiring the ability to move through peripheral tissues as well as the general lymphoid circulation. Although the mechanisms responsible for these alterations are not well understood, changes in chemokine receptor expression may play a critical role. To investigate these changes, the expression patterns of two chemokine receptors, CXCR3 and CXCR4, were compared on CD4+ T cells following activation in the MLR. By day 9 of activation, expression of the inflammatory chemokine receptor CXCR3 was up-regulated, while expression of the homeostatic chemokine receptor CXCR4 was down-regulated. Alterations in receptor expression occurred almost exclusively on a subpopulation of T cells that expressed higher levels of CD4. These CD4high T cells demonstrated many characteristics of activated T cells and had undergone division in the MLR. By day 9 of culture, the majority of CXCR3+ and CXCR4− cells had divided and had acquired an activated/memory phenotype (CD45RA− CD45RO+ CD69+ CD25+). The levels of transcripts for both CXCR3 and CXCR4 were increased upon allo-activation. The discrepancy between levels of CXCR4 mRNA and surface protein was not due to sequestration of the receptor in intracellular compartments, as CXCR4 was not detectable intracellularly. However, intracellular CXCR3 was readily detectable. Finally, cells from allogeneic cultures demonstrated enhanced migration toward IFN-inducible T cell α chemoattractant and reduced migration toward stromal cell-derived factor-1 compared with syngeneic controls, thus suggesting that the observed switch in receptor expression may at least partly contribute to the differential patterns of migration displayed by naive and memory T cells.
CD80 Costimulation Is Required for Th2 Cell Cytokine Production But Not for Antigen-Specific Accumulation and Migration into the Lung
Authors: Harris Nicola L. , Prout Melanie , Peach Robert J. , Fazekas de St. Groth Barbara , Ronchese Franca 
Published: April 2014

AbstractThe CD28 ligands CD80 and CD86 are expressed on APC, and both provide costimulatory function. However, the reason for the expression of two separate CD28 ligands remains unclear. We have previously shown that blockade of CD80 costimulation by Y100F-Ig, a CTL-associated Ag-4 (CTLA4)-Ig mutant that does not bind CD86, inhibits the development of lung inflammatory immune responses, but does not affect blood eosinophilia or Ab production. Each of those responses was inhibited by treatment with CTLA4-Ig, which binds both CD80 and CD86. To clarify the mechanism underlying these observations we have developed a model of lung inflammation using adoptively transferred CD4+ T cells expressing a Vα11+Vβ3+ transgenic TCR specific for I-Ek and moth cytochrome c. Treatment with Y100F-Ig inhibited the induction of lung eosinophilia in adoptively transferred mice. However, Y100F-Ig did not detectably affect the accumulation of Ag-specific T cells at the site of peptide deposit or in the draining lymphoid tissues. Acquisition of an activated phenotype and expression of adhesion molecules required for migration into the lung were modestly affected. Importantly, treatment with Y100F-Ig diminished the ability of T cells to produce the cytokines IL-4 and IL-5 following intranasal challenge with Ag. All the responses examined were severely inhibited by treatment with CTLA4-Ig. We conclude that T cells require CD80 costimulation for the optimal production of IL-5 following intranasal administration of Ag. Decreased IL-5 production is the most likely explanation for the diminished airway eosinophilia observed.
Modulation of Inhaled Antigen-Induced IgE Tolerance by Ongoing Th2 Responses in the Lung
Authors: Hurst Stephen D. , Seymour Brian W. P. , Muchamuel Tony , Kurup Viswanath P. , Coffman Robert L. 
Published: April 2014

Abstract
The normal response to inhaled Ag is the absence of Ag-specific IgE and cytokine production to later Ag challenges. Although the mechanism of this aerosol-induced IgE tolerance is not completely understood, it may prevent sensitization to inhaled Ags, which could otherwise lead to allergy and asthma. We examined the consequences of ongoing Th1 and Th2 responses in the lungs of mice during OVA inhalation to mimic conditions that may subvert tolerance and lead to sensitization. We found that concurrent, secondary Th2 lung responses to keyhole limpet hemocyanin or primary responses to Nippostrongylus larvae or Asperigillus fumagatus extract prevented establishment of IgE tolerance to aerosolized OVA. Intranasal rIL-4 given before OVA aerosolization also prevented establishment of tolerance, whereas concurrent Th1 responses to influenza virus or Mycobacterium bovis bacillus Calmette-Guérin had no effect. However, once established, aerosol tolerance to OVA could not be completely broken by OVA rechallenge concurrent with a secondary Th2 response to keyhole limpet hemocyanin or A. fumagatus extract, or by intranasal rIL-4. These data suggest that the immune status of the lung of an individual may profoundly influence the initial response to inhaled Ag, and that aerosol-induced IgE tolerance may not be appropriately established in individuals undergoing concurrent, Th2-mediated responses to Ags or pathogens.