bluuebunny/crossref_metadata_2025_split huggingface dataset:
IFN-γ Induces gp91phox Expression in Human Monocytes via Protein Kinase C-Dependent Phosphorylation of PU.1
Authors: Mazzi Paola , Donini Marta , Margotto Daniela , Wientjes Frans , Dusi Stefano 
Published: April 2014

Abstract
We previously reported that the stimulation of human blood monocytes with IFN-γ induces the binding of PU.1 to the gp91phox promoter and the consequent expression of gp91phox. In this study, we show that the effect of IFN-γ is reproduced by the serine phosphatase inhibitor, okadaic acid, and this suggests that serine kinases could be involved in gp91phox expression. We also show that IFN-γ induces the serine/threonine phosphorylation of PU.1 in cultured monocytes. This phosphorylation, as well as the IFN-γ-induced PU.1 binding and gp91phox protein synthesis, is slightly affected by the casein kinase II inhibitor, daidzein, but is abrogated by the protein kinase C (PKC) -α and -β inhibitor, Go6976, and by synthetic peptides with sequences based on the endogenous pseudosubstrate region of the classical PKC α and β isoforms. In contrast, peptides reproducing the pseudosubstrate region of PKC ε were without effect. Moreover, we found that the treatment of monocytes with IFN-γ induces the nuclear translocation and the activation of PKC α and βI, but not of PKC βII, and that the IFN-γ-induced phosphorylation of PU.1 was greatly reduced by LY333531, a selective inhibitor of PKC β isoforms. Finally, nuclear run-on assays demonstrated that while the PKC inhibitors, Go6976 and LY333531, decrease the IFN-γ-induced gp91phox transcription, the serine phosphatase inhibitor, okadaic acid, enhances the gp91phox gene transcription. Our results indicate that in cultured monocytes, IFN-γ induces the binding of PU.1 to the gp91phox promoter and the expression of gp91phox by phosphorylation of PU.1 via activation of PKC α and/or βI.
Janus Kinase 3 Down-Regulates Lipopolysaccharide-Induced IL-1β-Converting Enzyme Activation by Autocrine IL-10
Authors: Kim Hee-Jung , Hart Judy , Knatz Nina , Hall Mark W. , Wewers Mark D. 
Published: April 2014

AbstractProIL-1β processing by IL-1β-converting enzyme (ICE) and the subsequent release of mature IL-1β are highly regulated events in the monocyte/macrophage response to pathogens. This process occurs in a controlled way through the activation of the constitutively expressed 45-kDa ICE precursor (proICE). To characterize the signaling pathways involved in ICE regulation in human monocytes/macrophages, we analyzed ICE activation in the presence of specific inhibitors of classic signaling pathways. Although LPS-induced ICE activity was not significantly affected by interruption of extracellular signal-regulated kinase, p38 kinase, or phosphoinositol 3-kinase, Janus kinase 3 (JAK3) inhibition produced a significant dose-dependent enhancement of LPS-induced ICE activity. Support for the inhibitory role of JAK3 was shown by the fact that IL-4 (which uses JAK1 and JAK3 signaling) suppressed LPS-induced ICE activity and by the finding that JAK3 knockout macrophages have increased LPS-induced ICE activation. To understand how JAK3 down-regulates LPS-induced ICE activity in monocytes, we hypothesized that JAK3 signaling enhances IL-10 production. In support of this model we show that LPS-induced IL-10 expression was synchronous with ICE deactivation, IL-4 induced the release of IL-10, exogenous IL-10 suppressed LPS-induced ICE activity, a neutralizing IL-10 Ab increased LPS-induced ICE activity, and, finally, JAK3 knockout macrophages displayed significantly reduced LPS-induced IL-10 production. These findings support a model in which JAK3 signaling enhances IL-10 production leading to down-regulation of ICE activation and suppression of IL-1β processing and release.
Mast Cell-Independent Mechanisms of Immediate Hypersensitivity: A Role for Platelets
Authors: Cara Denise C. , Ebbert Kirsten V. J. , McCafferty Donna-Marie 
Published: April 2014

Abstract
Mast cells have been implicated as the central effectors in allergic responses, yet a fatal anaphylactic response can be induced in mast cell-deficient mice. In this study, we examined the immediate hypersensitivity response in wild-type (WT) and mast cell-deficient mice (W/Wv) in two different tissues (skin and skeletal muscle). Vascular permeability and leukocyte recruitment were studied after immediate challenge or 4 h postchallenge in OVA-sensitized mice. In skin, immediate challenge induced a significant increase in vascular permeability (75%) within 30 min and was accompanied by increased leukocyte adhesion 4 h postchallenge. In the absence of mast cells, no changes in vascular permeability or leukocyte recruitment were observed in skin. In WT skeletal muscle, immediate challenge induced a rapid increase (80%) in vascular permeability within 5 min and significant leukocyte recruitment after 4 h. Surprisingly, in W/Wv, a gradual increase in vascular permeability was observed, reaching a maximum (50%) within 30 min. Despite the absence of mast cells, subsequent leukocyte emigration was similar to that observed in WT mice. Pretreatment with anti-platelet serum in W/Wv returned Ag-induced vascular permeability and leukocyte recruitment to baseline. Platelets were shown to interact with endothelium in skeletal muscle, but not dermal microvasculature. These data illustrate that mast cells play a prominent role in vascular permeability and leukocyte recruitment in skin in response to Ag, however, in skeletal muscle; these changes can occur in the absence of mast cells, and are mediated, in part, by the presence of platelets.
Does HLA-Dependent Chimerism Underlie the Pathogenesis of Juvenile Dermatomyositis?
Authors: Reed Ann M. , McNallan Kelly , Wettstein Peter , Vehe Richard , Ober Carole 
Published: April 2014

AbstractJuvenile dermatomyositis (JDM) is a multisystem autoimmune disease that at times resembles chronic graft-vs-host disease. This led us to suggest that nonself cells may play a role in the disease process. In this study we examined the relationship between HLA genotype and the presence of maternally derived chimeric cells in JDM patients and healthy controls, and assessed immunologic activity in the chimeric cells. We identified chimeric cells more often in children with JDM (60 of 72) than in their unaffected siblings (11 of 48) or in healthy controls (5 of 29). The presence of chimerism in the JDM patients, their healthy siblings, and unaffected control children was associated with a HLA-DQA1*0501 allele in the mother (p = 0.011). Further, we show that maternally transferred chimeric T cells are responsive to the host’s (JDM childs’) lymphocytes (33.75 ± 8.4 IFN-γ-producing cells from JDM cells vs 5.0 ± 1.25 from maternal cells), and that this is a memory response. These combined data indicate that chimeric cells play a direct role in the JDM disease process and that the mother’s HLA genotype facilitates the transfer and/or persistence of maternal cells in the fetal circulation.
Strain Distribution Pattern of Susceptibility to Immune-Mediated Nephritis
Authors: Xie Chun , Sharma Ruchi , Wang Hongwei , Zhou Xin J. , Mohan Chandra 
Published: April 2014

Abstract
The genetic basis of immune-mediated nephritis is poorly understood. Recent studies have demonstrated that the NZW mouse strain is more prone to immune-mediated nephritis compared with C57BL/6 and BALB/c strains. The present study extends these findings by challenging 12 additional inbred strains of mice with rabbit anti-mouse glomerular basement membrane (GBM) reactive sera. Compared with control sera-injected mice and anti-GBM-injected A/J, AKR/J, C3H/HeJ, DBA/2J, MRL/MpJ, NOD/LtJ, P/J, SJL/J, and SWR/J mice, the anti-GBM-injected BUB/BnJ, DBA/1J, and 129/svJ mice developed severe proteinuria and azotemia. Their kidneys exhibited pronounced glomerulonephritis, with crescent formation, as well as tubulointerstitial disease, with these phenotypes being particularly profound in 129/svJ mice. However, these strains did not appear to differ in the nature of their xenogeneic immune response to the administered rabbit sera, either quantitatively or qualitatively. Collectively, these findings allude to the presence of genetic elements in the BUB/BnJ, DBA/1J, and 129/svJ genomes that may potentially confer susceptibility to immune-mediated nephritis. Detailed studies to dissect out the immunological and genetic basis of renal disease in these three strains are clearly warranted.
B Cell Selection Defects Underlie the Development of Diabetogenic APCs in Nonobese Diabetic Mice
Authors: Silveira Pablo A. , Dombrowsky Joseph , Johnson Ellis , Chapman Harold D. , Nemazee David , Serreze David V. 
Published: April 2014

AbstractOne mechanism whereby B cells contribute to type 1 diabetes in nonobese diabetic (NOD) mice is as a subset of APCs that preferentially presents MHC class II-bound pancreatic β cell Ags to autoreactive CD4 T cells. This results from their ability to use cell surface Ig to specifically capture β cell Ags. Hence, we postulated a diabetogenic role for defects in the tolerance mechanisms normally blocking the maturation and/or activation of B cells expressing autoreactive Ig receptors. We compared B cell tolerance mechanisms in NOD mice with nonautoimmune strains by using the IgHEL and Ig3-83 transgenic systems, in which the majority of B cells recognize one defined Ag. NOD- and nonautoimmune-prone mice did not differ in ability to delete or receptor edit B cells recognizing membrane-bound self Ags. However, in contrast to the nonautoimmune-prone background, B cells recognizing soluble self Ags in NOD mice did not undergo partial deletion and were also not efficiently anergized. The defective induction of B cell tolerance to soluble autoantigens is most likely responsible for the generation of diabetogenic APC in NOD mice.
Identification of Multiple HLA-DR-Restricted Epitopes of the Tumor-Associated Antigen CAMEL by CD4+ Th1/Th2 Lymphocytes
Authors: Slager Elisabeth H. , van der Minne Caroline E. , Krüse Margreet , Krueger Dilja D. , Griffioen Marieke , Osanto Susanne 
Published: April 2014

Abstract
CD4+ Th cells play an important role in the induction and maintenance of adequate CD8+ T cell-mediated antitumor responses. Therefore, identification of MHC class II-restricted tumor antigenic epitopes is of major importance for the development of effective immunotherapies with synthetic peptides. CAMEL and NY-ESO-ORF2 are tumor Ags translated in an alternative open reading frame from the highly homologous LAGE-1 and NY-ESO-1 genes, respectively. In this study, we investigated whether CD4+ T cell responses could be induced in vitro by autologous, mature dendritic cells pulsed with recombinant CAMEL protein. The data show efficient induction of CAMEL-specific CD4+ T cells with mixed Th1/Th2 phenotype in two healthy donors. Isolation of CD4+ T cell clones from the T cell cultures of both donors led to the identification of four naturally processed HLA-DR-binding CAMEL epitopes: CAMEL1–20, CAMEL14–33, CAMEL46–65, and CAMEL81–102. Two peptides (CAMEL1–20 and CAMEL14–33) also contain previously identified HLA class I-binding CD8+ T cell epitopes shared by CAMEL and NY-ESO-ORF2 and are therefore interesting tools to explore for immunotherapy. Furthermore, two CD4+ T cell clones that recognized the CAMEL14–33 peptide with similar affinities were shown to differ in recognition of tumor cells. These CD4+ T cell clones recognized the same minimal epitope and expressed similar levels of adhesion, costimulatory, and inhibitory molecules. TCR analysis demonstrated that these clones expressed identical TCR β-chains, but different complementarity-determining region 3 loops of the TCR α-chains. Introduction of the TCRs into proper recipient cells should reveal whether the different complementarity-determining region 3α loops are important for tumor cell recognition.
HLA-B27 in Transgenic Rats Forms Disulfide-Linked Heavy Chain Oligomers and Multimers That Bind to the Chaperone BiP
Authors: Tran Tri Minh , Satumtira Nimman , Dorris Martha L. , May Ekkehard , Wang Andrew , Furuta Eiichi , Taurog Joel D. 
Published: April 2014

Abstract
To test the hypothesis that HLA-B27 predisposes to disease by forming disulfide-linked homodimers, we examined rats transgenic for HLA-B27, mutant Cys67Ser HLA-B27, or HLA-B7. In splenic Con A blasts from high transgene copy B27 lines that develop inflammatory disease, the anti-H chain mAb HC10 precipitated four bands of molecular mass 78–105 kDa and additional higher molecular mass material, seen by nonreducing SDS-PAGE. Upon reduction, all except one 78-kDa band resolved to 44 kDa, the size of the H chain monomer. The 78-kDa band was found to be BiP/Grp78, and the other high molecular mass material was identified as B27 H chain. Analysis of a disease-resistant low copy B27 line showed qualitatively similar high molecular mass bands that were less abundant relative to H chain monomer. Disease-prone rats with a Cys67Ser B27 mutant showed B27 H chain bands at 95 and 115 kDa and a BiP band at 78 kDa, whereas only scant high molecular mass bands were found in cells from control HLA-B7 rats. 125I-surface labeled B27 oligomers were immunoprecipitated with HC10, but not with a mAb to folded B27-β2-microglobulin-peptide complexes. Immunoprecipitation of BiP with anti-BiP Abs coprecipitated B27 H chain multimers. Folding and maturation of B27 were slow compared with B7. These data indicate that disulfide-linked intracellular H chain complexes are more prone to form and bind BiP in disease-prone wild-type B27 and B27-C67S rats than in disease-resistant HLA-B7 rats. The data support the hypothesis that accumulation of misfolded B27 participates in the pathogenesis of B27-associated disease.
Cutting Edge: TGF-β Induces a Regulatory Phenotype in CD4+CD25− T Cells through Foxp3 Induction and Down-Regulation of Smad7
Authors: Fantini Massimo C. , Becker Christoph , Monteleone Giovanni , Pallone Francesco , Galle Peter R. , Neurath Markus F. 
Published: April 2014

Abstract
CD4+CD25+ regulatory cells are a subpopulation of T lymphocytes of thymic origin. However, recent data suggest an alternative commitment of regulatory T cells in the periphery, although the precise mechanism is unknown. In the present work, we demonstrate that TGF-β is able to induce Foxp3 expression and subsequently a regulatory phenotype in CD4+CD25− peripheral murine T cells. Similarly, TGF-β induced Foxp3 in human CD4+CD25− T cells. Moreover, we show that the inhibitory Smad7 protein that is normally induced by TGF-β and limits TGF-β signaling, is strongly down-regulated by Foxp3 at the transcriptional level. Foxp3-mediated down-regulation of Smad7 subsequently rendered CD4+CD25− T cells highly susceptible to the morphogenic and regulatory effects of TGF-β signaling via Smad3/4. In summary, we demonstrate that TGF-β induces a regulatory phenotype in CD4+CD25− T cells through the induction of Foxp3 and a positive autoregulatory loop of TGF-β signaling due to the absence of Smad7.
Breaking Immune Tolerance to the Prion Protein Using Prion Protein Peptides Plus Oligodeoxynucleotide-CpG in Mice
Authors: Rosset Martine Bruley , Ballerini Clara , Gregoire Sylvie , Metharom Pat , Carnaud Claude , Aucouturier Pierre 
Published: April 2014

Abstract
The absence of a detectable immune response during transmissible spongiform encephalopathies is likely due to the fact that the essential component of infectious agents, the prion protein (PrP), is a self Ag expressed on the surface of many cells of the host. To overcome self-tolerance to PrP, we used 30-mer PrP peptides previously shown to be immunogenic in Prnp−/− mice, together with CFA or CpG-oligodeoxynucleotides (CpG) in IFA. Generation of anti-PrP T and B cell responses was analyzed in the spleen, lymph nodes, and serum of immunized C57BL/6 wild-type mice. Immunization with PrP peptides emulsified in CFA did not trigger an immune response to PrP. When CpG were used, vaccination with peptides P143–172 and P158–187 generated IFN-γ-secreting splenic T cells, and only P158–187 significantly stimulated IL-4-secreting T cells. Both peptides induced few Ab-producing B cells, and low and variable serum Ab titers. In contrast, immunization with peptide P98–127 did not induce significant levels of T cell responses but elicited specific peptide Abs. T cell epitope mapping, performed using 15-mer peptides covering PrP segment 142–182, revealed that an immunogenic motif lies between positions 156 and 172. These results demonstrate that T and B cell repertoires against PrP can be stimulated in C57BL/6 when adjuvant of the innate immunity such as CpG, but not CFA, is added to PrP peptides, and that the pattern of immune responses varies according to the epitope.
Enzymatically Quiescent Heparanase Augments T Cell Interactions with VCAM-1 and Extracellular Matrix Components under Versatile Dynamic Contexts
Authors: Sotnikov Ilya , Hershkoviz Rami , Grabovsky Valentin , Ilan Neta , Cahalon Liora , Vlodavsky Israel , Alon Ronen , Lider Ofer 
Published: April 2014

Abstract
During their migration into inflammatory sites, immune cells, such as T cells, secrete extracellular matrix (ECM)-degrading enzymes, such as heparanase, which, under mildly acidic conditions, degrade heparan sulfate proteoglycans (HSPG). We have previously shown that at pH 7.2, human placental heparanase loses its enzymatic activity, while retaining its ability to bind HSPG and promote T cell adhesion to unfractionated ECM. We now demonstrate that the 65-kDa recombinant human heparanase, which is devoid of enzymatic activity, but can still bind HSPG, captures T cells under shear flow conditions and mediates their rolling and arrest, in the absence or presence of stromal cell-derived factor 1α (SDF-1α; CXCL12), in an α4β1-VCAM-1-dependent manner. Furthermore, heparanase binds to and induces T cell adhesion to key ECM components, like fibronectin and hyaluronic acid, in β1 integrin- and CD44-specific manners, respectively, via the activation of the protein kinase C and phosphatidylinositol 3-kinase intracellular signaling machineries. Although the nature of the putative T cell heparanase-binding moiety is unknown, it appears that heparanase exerts its proadhesive activity by interacting with the T cells’ surface HSPG, because pretreatment of the cells with heparinase abolished their subsequent response to heparanase. Also, heparanase augmented the SDF-1α-triggered phosphorylation of Pyk-2 and extracellular signal-regulated kinase-2 implicated in integrin functioning. Moreover, heparanase, which had no chemotactic effect on T cells on its own, augmented the SDF-1α-induced T cell chemotaxis across fibronectin. These findings add another dimension to the known versatility of heparanase as a key regulator of T cell activities during inflammation, both in the context of the vasculature and at extravascular sites.
Platelets, after Exposure to a High Shear Stress, Induce IL-10-Producing, Mature Dendritic Cells In Vitro
Authors: Hagihara Masao , Higuchi Ayako , Tamura Noriko , Ueda Yoko , Hirabayashi Kaori , Ikeda Yasuo , Kato Shunichi , Sakamoto Shinji , Hotta Tomomitsu , Handa Shunnosuke , Goto Shinya 
Published: April 2014

Abstract
There is evidence for immune system involvement in atherogenesis. In the present study the effect of platelets on dendritic cells (DC), an important immunologic regulator, was examined in vitro. Platelet-rich plasma, after exposure to shear stress, was added to human monocyte-derived immature DC, which were then examined for surface Ag expression, allogeneic T lymphocyte stimulatory activity, and cytokine production. After exposure, the number of anti-CD40 ligand (anti-CD40L) and anti-P-selectin IgG molecules bound per platelet was increased. These activated platelets induced DC maturation, as revealed by significant up-regulation of CD83, CD80, and CD86 Ags. The addition of platelets in the presence of IFN-γ plus LPS significantly enhanced IL-10 production from immature DC. After platelet addition, mature DC provoked a significant proliferation of allogeneic naive T lymphocytes. These activated T cells showed lower IFN-γ production than those stimulated by LPS- and IFN-γ-treated DC. CD40L on the platelet surface was not involved in maturation of DC, as mAb to CD40L failed to block maturation. The effect of platelets was observed even if platelets and DC were separated using large pore-sized membranes or when platelets were depleted from plasma by centrifugation. Furthermore, it was abrogated after the depletion of protein fraction. Thus, soluble protein factors excreted from activated platelets contribute to IL-10-producing DC maturation.
κ Editing Rescues Autoreactive B Cells Destined for Deletion in Mice Transgenic for a Dual Specific Anti-Laminin Ig
Authors: Brady Graham F. , Congdon Kendra L. , Clark Amy G. , Sackey Faustina N. A. , Rudolph Earl H. , Radic Marko Z. , Foster Mary H. 
Published: April 2014

Abstract
We explored mechanisms involved in B cell self-tolerance in a double- and triple-transgenic mouse model bearing the LamH-Cμ Ig H chain conventional transgene and a gene-targeted replacement for a functional Vκ8Jκ5 L chain gene. Whereas the H chain is known to generate anti-laminin Ig in combination with multiple L chains, the H + L Ig binds ssDNA in addition to laminin. Immune phenotyping indicates that H + L transgenic B cells are regulated by clonal deletion, receptor editing via secondary rearrangements at the nontargeted κ allele, and anergy. Collectively, the data suggest that multiple receptor-tolerogen interactions regulate autoreactive cells in the H + L double-transgenic mice. Generation of H + LL triple-transgenic mice homozygous for the targeted L chain to exclude secondary κ rearrangements resulted in profound B cell depletion with absence of mature B cells in the bone marrow. We propose that the primary tolerogen of dual reactive B cells in this model is not ssDNA, but a strongly cross-linking tolerogen, presumably basement membrane laminin, that triggers recombination-activating gene activity, L chain editing, and deletion.
Autoreactive T Cells Persist in Rats Protected against Experimental Autoimmune Encephalomyelitis and Can Be Activated through Stimulation of Innate Immunity
Authors: Conant Stephanie B. , Swanborg Robert H. 
Published: April 2014

AbstractLewis rats can be rendered unresponsive to experimental autoimmune encephalomyelitis by immunization with myelin basic protein (MBP), or MBP68–86, the dominant encephalitogenic MBP epitope for this strain, administered in IFA. However, protected rats harbor potentially encephalitogenic T cells, which are maintained in an inactive state. We investigated whether these quiescent effector cells could be activated in vitro. Although these T cells respond poorly to MBP68–86, they proliferate vigorously whether cocultured with MBP68–86 and either IL-2 or IL-12, suggesting that the T cells are in a state of anergy. Moreover, we could activate these anergic T cells with peptide and cytosine-guanine dinucleotide (CpG) oligonucleotide, but not control oligonucleotide, suggesting that products of the innate immune response are capable of activating anergic autoreactive T cells. The activated T cells produced the proinflammatory cytokine, IFN-γ in response to IL-12, and IL-6 was secreted in response to CpG oligonucleotide. IL-6 has been reported to play a role in T cell activation by blocking T regulatory/suppressor (Treg) cell-mediated suppression through a Toll-like receptor-dependent pathway. However, anti-IL-6 mAb did not block CpG activation of the anergized cells. In contrast, anti-TGF-β1 Ab released the unresponsive T cells from the anergic state in the presence of MBP68–86, whereas TGF-β1 inhibited proliferation of MBP68–86- plus CpG-activated T cells. Because TGF-β1 has previously been implicated in Treg activity, this finding is consistent with a role for Treg cells in maintaining autoreactive T cells in the anergic state.