bluuebunny/crossref_metadata_2025_split huggingface dataset:
Orderly Pattern of Development of the Autoantibody Response in (New Zealand White × BXSB)F1 Lupus Mice: Characterization of Target Antigens and Antigen Spreading by Two-Dimensional Gel Electrophoresis and Mass Spectrometry
Authors: Thébault Sandrine , Gilbert Danièle , Hubert Marie , Drouot Laurent , Machour Nadine , Lange Catherine , Charlionet Roland , Tron François 
Published: April 2014

AbstractImmunoblots of a two-dimensional PAGE-separated HL-60 cell proteomic map and mass spectrometry were combined to characterize proteins targeted by autoantibodies produced by male (New Zealand White × BXSB)F1 (WB) mice that develop lupus and anti-phospholipid syndrome. Analysis of sera sequentially obtained from seven individual mice at different ages showed that six proteins, vimentin, heat shock protein 60, UV excision-repair protein RAD23, α-enolase, heterogeneous nuclear ribonucleoprotein L, and nucleophosmin, were the targets of the B cell autoimmune response, and that autoantibodies to them were synthesized sequentially in an orderly pattern that recurred in all the male WB mice analyzed: anti-vimentin first and anti-nucleophosmin last, with anti-RAD23 and anti-heat shock protein 60, then anti-α-enolase and anti-heterogeneous nuclear ribonucleoprotein L Abs occuring concomitantly. Anti-vimentin reactivity always appeared before anti-cardiolipin and anti-DNA Abs, suggesting that vimentin is the immunogen initiating the autoimmune process. The pattern of HL-60 proteins recognized by female WB sera differed from that of male sera, indicating that the Y chromosome-linked autoimmune acceleration gene is not an accelerator but a strong modifier of the autoimmune response. Thus, 1) combining two-dimensional PAGE and mass spectrometry constitutes a powerful tool to identify the set of Ags bound by autoantibodies present in a single serum and the whole autoantibody pattern of an autoimmune disease; 2) the diversification of the autoimmune response in male WB mice occurs in a predetermined pattern consistent with Ag spreading, and thus provides a useful model to further our understanding of the development of the autoantibody response in lupus.
Neonatal Tolerance in the Absence of Stat4- and Stat6- Dependent Th Cell Differentiation
Authors: Chang Hua-Chen , Zhang Shangming , Kaplan Mark H. 
Published: April 2014

AbstractNeonatal tolerance to specific Ag is achieved by nonimmunogenic exposure within the first day of life. The mechanism that regulates this tolerance may provide the basis for successful organ transplantation and has recently been thought to be immune deviation from the inflammatory Th1 response to a Th2 response. To test the importance of Th2 cells in the establishment of neonatal tolerance, we examined neonatal tolerance in Stat4- and Stat6-deficient mice, which have reduced Th1 and Th2 cell development, respectively. Neonatal tolerance of both the T and B cell compartments in Stat4- and Stat6-deficient mice was similar to that observed in wild-type mice. Cytokine production shifted from a Th1 to a Th2 response in wild-type mice tolerized as neonates. In contrast, tolerance was observed in Stat6-deficient mice despite maintenance of a Th1 cytokine profile. These results suggest that cells distinct from Stat6-dependent Th2 cells are required for the establishment of neonatal tolerance.
Requirement for the p75 TNF-α Receptor 2 in the Regulation of Airway Hyperresponsiveness by γδ T Cells
Authors: Kanehiro Arihiko , Lahn Michael , Mäkelä Mika J. , Dakhama Azzeddine , Joetham Anthony , Rha Yeong-Ho , Born Willi , Gelfand Erwin W. 
Published: April 2014

AbstractIn a recent study, we found that TNF-α negatively regulates airway responsiveness through the activation of γδ T cells. The biological activities of TNF-α are mediated by two structurally related but functionally distinct receptors, p55 (TNFR1) and p75 (TNFR2), which are independently expressed on the cell surface. However, the relative importance of either TNFR in airway hyperresponsiveness (AHR) is unknown. To investigate the importance of these TNFRs in the development of allergen-induced AHR, p55-deficient and p75-deficient mice were sensitized to OVA by i.p. injection and subsequently challenged with OVA via the airways; airway responsiveness to inhaled methacholine was monitored. p75-deficient mice developed AHR to a similar degree as control mice. In contrast, p55-deficient mice, which were sensitized and challenged with OVA, failed to develop AHR. In p55-deficient mice, both the numbers of eosinophils and levels of IL-5 in bronchoalveolar lavage fluid were significantly lower than in sensitized/challenged control mice (p &lt; 0.05). However, depletion of γδ T cells resulted in significant increases in AHR in the p55-deficient mice, whereas no significant effect of γδ T cell depletion was evident in the p75-deficient mice. These data indicate that, in the absence of TNFR1 (p55), where TNF-α uses the p75 pathway exclusively, the development of AHR is regulated by γδ T cells.
T Cell-Independent Regulation of IgE Antibody Production Induced by Surface-Linked Liposomal Antigen
Authors: Taneichi Maiko , Naito Seishiro , Kato Hiroshi , Tanaka Yuriko , Mori Masahito , Nakano Yoshio , Yamamura Hiroyuki , Ishida Hiroshi , Komuro Katsutoshi , Uchida Tetsuya 
Published: April 2014

AbstractControl of IgE Ab production is important for the prevention of IgE-related diseases. However, in contrast to the existing information on the induction of IgE production, little is known about the regulation of the production of this isotype, with the exception of the well-documented mechanism involving T cell subsets and their cytokine products. In this study, we demonstrate an alternative approach to interfere with the production of IgE, independent of the activity of T cells, which was discovered during the course of an investigation intended to clarify the mechanism of IgE-selective unresponsiveness induced by surface-coupled liposomal Ags. Immunization of mice with OVA-liposome conjugates induced IgE-selective unresponsiveness without apparent Th1 polarization. Neither IL-12, IL-10, nor CD8+ T cells participated in the regulation. Furthermore, CD4+ T cells of mice immunized with OVA-liposome were capable of inducing Ag-specific IgE synthesis in athymic nude mice immunized with alum-adsorbed OVA. In contrast, immunization of the recipient mice with OVA-liposome did not induce anti-OVA IgE production, even when CD4+ T cells of mice immunized with alum-adsorbed OVA were transferred. In the secondary immune response, OVA-liposome enhanced anti-OVA IgG Ab production, but it did not enhance ongoing IgE production, suggesting that the IgE-selective unresponsiveness induced by the liposomal Ag involved direct effects on IgE, but not IgG switching in vivo. These results suggest the existence of an alternative mechanism not involving T cells in the regulation of IgE synthesis.
Transcriptional Regulation of Fcgr2b Gene by Polymorphic Promoter Region and Its Contribution to Humoral Immune Responses
Authors: Xiu Yan , Nakamura Kazuhiro , Abe Masaaki , Li Na , Wen Xiang Shu , Jiang Yi , Zhang Danqing , Tsurui Hiromichi , Matsuoka Shuji , Hamano Yoshitomo , Fujii Hiroyuki , Ono Masao , Takai Toshiyuki , Shimokawa Toshibumi , Ra Chisei , Shirai Toshikazu , Hirose Sachiko 
Published: April 2014

Abstract
FcγRIIB1 molecules serve as negative feedback regulator for B cell Ag receptor-elicited activation of B cells; thus, any impaired FcγRIIB1 function may possibly be related to aberrant B cell activation. We earlier found deletion polymorphism in the Fcgr2b promoter region among mouse strains in which systemic autoimmune disease-prone NZB, BXSB, MRL, and autoimmune diabetes-prone nonobese diabetic, but not NZW, BALB/c, and C57BL/6 mice have two identical deletion sites, consisting of 13 and 3 nucleotides. In this study, we established congenic C57BL/6 mice for NZB-type Fcgr2b allele and found that NZB-type allele down-regulates FcγRIIB1 expression levels in germinal center B cells and up-regulates IgG Ab responses. We did luciferase reporter assays to determine whether NZB-type deletion polymorphism affects transcriptional regulation of Fcgr2b gene. Although NZW- and BALB/c-derived segments from position −302 to +585 of Fcgr2b upstream region produced significant levels of luciferase activities, only a limited activity was detected in the NZB-derived sequence. EMSA and Southwestern analysis revealed that defect in transcription activity in the NZB-derived segment is likely due to absence of transactivation by AP-4, which binds to the polymorphic 13 nucleotide deletion site. Our data imply that because of the deficient AP-4 binding, the NZB-type Fcgr2b allele polymorphism results in up-regulation of IgG Ab responses through down-regulation of FcγRIIB1 expression levels in germinal center B cells, and that such polymorphism may possibly form the basis of autoimmune susceptibility in combination with other background contributing genes.
Distinct Roles for c-Myb and Core Binding Factor/Polyoma Enhancer-Binding Protein 2 in the Assembly and Function of a Multiprotein Complex on the TCR δ Enhancer In Vivo
Authors: Hernández-Munain Cristina , Krangel Michael S. 
Published: April 2014

Abstract
Enhancers and promoters within TCR loci functionally collaborate to modify chromatin structure and to confer accessibility to the transcription and V(D)J recombination machineries during T cell development in the thymus. Two enhancers at the TCRαδ locus, the TCR α enhancer and the TCR δ enhancer (Eδ), are responsible for orchestrating the distinct developmental programs for V(D)J recombination and transcription of the TCR α and δ genes, respectively. Eδ function depends critically on transcription factors core binding factor (CBF)/polyoma enhancer-binding protein 2 (PEBP2) and c-Myb as measured by transcriptional activation of transiently transfected substrates in Jurkat cells, and by activation of V(D)J recombination within chromatin-integrated substrates in transgenic mice. To understand the molecular mechanisms for synergy between these transcription factors in the context of chromatin, we used in vivo footprinting to study the requirements for protein binding to Eδ within wild-type and mutant versions of a human TCR δ minilocus in stably transfected Jurkat cells. Our data indicate that CBF/PEBP2 plays primarily a structural role as it induces a conformational change in the enhanceosome that is associated with augmented binding of c-Myb. In contrast, c-Myb has no apparent affect on CBF/PEBP2 binding, but is critical for transcriptional activation. Thus, our data reveal distinct functions for c-Myb and CBF/PEBP2 in the assembly and function of an Eδ enhanceosome in the context of chromatin in vivo.
Uniquely Conformed Peptide-Containing β2-Microglobulin- Free Heavy Chains of HLA-B2705 on the Cell Surface
Authors: Malik Pratap , Klimovitsky Polina , Deng Lih-Wen , Boyson Jonathan E. , Strominger Jack L. 
Published: April 2014

AbstractThe human class I MHC molecules are known to generally exist on the cell surface either as peptide-containing complexes of H chain (α-chain) and β2-microglobulin (β2m) or as β2m-free H chains incapable of binding peptides. In this study, a uniquely conformed peptide-containing β2m-free HLA-B2705 H chain has been isolated using the recently described highly efficient perfusion-affinity chromatography system for purification of class I MHC protein molecules. This form recognized by the mAb MARB4 is very closely associated with the remainder of the peptide containing HLA-B2705/β2m complex reactive with mAb ME1 and is present to ∼1–10% of mAb ME1 reactive forms on the cell surface. Also, HLA-B2705 purified using the mAb ME1 affinity column includes this unique mAb MARB4-reactive, unusually stable peptide-containing β2m-free form. A peptide nonamer GRWRGWYTY was isolated and identified from this β2m-free HLA-B2705 H chain and was used to assemble the mAb MARB4 reactive form efficiently on the surface of cells expressing HLA-B2705. The discovery of this form opens new avenues for further investigation of the role of HLA-B27 in spondyloarthropathies.
Modification of a Tumor-Derived Peptide at an HLA-A2 Anchor Residue Can Alter the Conformation of the MHC-Peptide Complex: Probing with TCR-Like Recombinant Antibodies
Authors: Denkberg Galit , Klechevsky Eynav , Reiter Yoram 
Published: April 2014

Abstract
A common assumption about peptide binding to the class I MHC complex is that each residue in the peptide binds independently. Based on this assumption, modifications in class I MHC anchor positions were used to improve the binding properties of low-affinity peptides (termed altered peptide ligands), especially in the case when tumor-associated peptides are used for immunotherapy. Using a new molecular tool in the form of recombinant Abs endowed with Ag-specific MHC-restricted specificity of T cells, we show that changes in the identity of anchor residues may have significant effects, such as altering the conformation of the peptide-MHC complex, and as a consequence, may affect the TCR-contacting residues. We herein demonstrate that the binding of TCR-like recombinant Abs, specific for the melanoma differentiation Ag gp100 T cell epitope G9-209, is entirely dependent on the identity of a single peptide anchor residue at position 2. An example is shown in which TCR-like Abs can recognize the specific complex only when a modified peptide, G9-209-2 M, with improved affinity to HLA-A2 was used, but not with the unmodified natural peptide. Importantly, these results demonstrate, using a novel molecular tool, that modifications at anchor residues can dramatically influence the conformation of the MHC peptide groove and thus may have a profound effect on TCR interactions. Moreover, these results may have important implications in designing modifications in peptides for cancer immunotherapy, because most such peptides studied are of low affinity.
Role of STAT6 and Mast Cells in IL-4- and IL-13-Induced Alterations in Murine Intestinal Epithelial Cell Function
Authors: Madden Kathleen B. , Whitman Lucia , Sullivan Carolyn , Gause William C. , Urban Joseph F. , Katona Ildy M. , Finkelman Fred D. , Shea-Donohue Terez 
Published: April 2014

AbstractGastrointestinal nematode infections generally invoke a type 2 cytokine response, characterized by the production of IL-4, IL-5, IL-9, and IL-13. Among these cytokines, IL-4 and IL-13 exhibit a functional overlap that can be explained by the sharing of a common receptor or receptor component (IL-4Rα). Binding of IL-4 by either the type 1 or 2 IL-4R, or of IL-13 by the type 2 IL-4R, initiates Jak-dependent tyrosine phosphorylation of the IL-4Rα-chain and the transcription factor, STAT6. In the present study, we investigated: 1) whether IL-13 has effects on intestinal epithelial cells similar to those observed with IL-4, and 2) whether the effects of IL-4 and IL-13 depend on STAT6 signaling and/or mast cells. BALB/c, STAT6−/−, and mast cell-deficient W/Wv mice or their +/+ littermates were treated with a long-lasting formulation of recombinant mouse IL-4 (IL-4C) or with IL-13 for seven days. Segments of jejunum were mounted in Ussing chambers to measure mucosal permeability; chloride secretion in response to PGE2, histamine, 5-hydroxytryptamine, or acetylcholine; and Na+-linked glucose absorption. IL-4C and IL-13 increased mucosal permeability, decreased glucose absorption, and decreased chloride secretion in response to 5-hydroxytryptamine. These effects were dependent on STAT6 signaling. Responses to PGE2 and histamine, which were dependent on mast cells and STAT6, were enhanced by IL-4C, but not by IL-13. The effects of IL-4 and IL-13 on intestinal epithelial cell function may play a critical role in host protection against gastrointestinal nematodes.
An Increase in the Susceptibility of Burned Patients to Infectious Complications Due to Impaired Production of Macrophage Inflammatory Protein 1α
Authors: Kobayashi Makiko , Takahashi Hitoshi , Sanford Arthur P. , Herndon David N. , Pollard Richard B. , Suzuki Fujio 
Published: April 2014

AbstractSepsis is a major mortality concern with burned patients, who have an increased susceptibility to infectious complications. PBMC from 41 of 45 severely burned patients (91%) failed to produce macrophage inflammatory protein 1α (MIP-1α) in cultures, while 2355–6900 pg/ml MIP-1α were produced by healthy donor PBMC, stimulation with anti-human CD3 mAb. Healthy chimeras (SCID mice inoculated with healthy donor PBMC) treated with anti-human MIP-1α mAb and patient chimeras (SCID mice reconstituted with burned patient PBMC) were susceptible (0% survival) to infectious complications induced by well-controlled cecal ligation and puncture. In contrast, patient chimeras treated with human recombinant MIP-1α and healthy chimeras were resistant (∼77–81% survival). Similarly, after anti-mouse CD3 mAb stimulation, splenic mononuclear cells from burned mice (6 h to 3 days after thermal injury) did not produce significant amounts of MIP-1α in their culture fluids. Normal mice treated with anti-murine MIP-1α mAb and burned mice were susceptible to cecal ligation- and puncture-induced infectious complications, while burned mice treated with murine recombinant MIP-1α and normal mice were resistant. Burned patients seemed to be more susceptible to infectious complications when the production of MIP-1α was impaired.
Thrombin Induces Mast Cell Adhesion to Fibronectin: Evidence for Involvement of Protease-Activated Receptor-1
Authors: Vliagoftis Harissios 
Published: April 2014

AbstractThrombin activates mast cells to release inflammatory mediators through a mechanism involving protease-activated receptor-1 (PAR-1). We hypothesized that PAR-1 activation would induce mast cell adhesion to fibronectin (FN). Fluorescent adhesion assay was performed in 96-well plates coated with FN (20 μg/ml). Murine bone marrow cultured mast cells (BMCMC) were used after 3–5 wk of culture (&gt;98% mast cells by flow cytometry for c-Kit expression). Thrombin induced β-hexosaminidase, IL-6, and matrix metalloproteinase-9 release from BMCMC. Thrombin and the PAR-1-activating peptide AparafluoroFRCyclohexylACitY-NH2 (cit) induced BMCMC adhesion to FN in a dose-dependent fashion, while the PAR-1-inactive peptide FSLLRY-NH2 had no effect. Thrombin and cit induced also BMCMC adhesion to laminin. Thrombin-mediated adhesion to FN was inhibited by anti-α5 integrin Ab (51.1 ± 6.7%; n = 5). The combination of anti-α5 and anti-α4 Abs induced higher inhibition (65.7 ± 7.1%; n = 5). Unlike what is known for FcεRI-mediated adhesion, PAR-1-mediated adhesion to FN did not increase mediator release. We then explored the signaling pathways involved in PAR-1-mediated mast cell adhesion. Thrombin and cit induced p44/42 and p38 phosphorylation. Pertussis toxin inhibited PAR-1-mediated BMCMC adhesion by 57.3 ± 7.3% (n = 4), indicating that Gi proteins are involved. Wortmannin and calphostin almost completely inhibited PAR-1-mediated mast cell adhesion, indicating that PI-3 kinase and protein kinase C are involved. Adhesion was partially inhibited by the mitogen-activated protein kinase kinase 1/2 inhibitor U0126 (24.5 ± 3.3%; n = 3) and the p38 inhibitor SB203580 (25.1 ± 10.4%; n = 3). The two inhibitors had additive effects. Therefore, thrombin mediates mast cell adhesion through the activation of Gi proteins, phosphoinositol 3-kinase, protein kinase C, and mitogen-activated protein kinase pathways.
P-Selectin, and Not E-Selectin, Negatively Regulates Murine Megakaryocytopoiesis
Authors: Banu Naheed , Avraham Shalom , Avraham Hava Karsenty 
Published: April 2014

Abstract
To assess the role of P-selectin and E-selectin in megakaryocytopoiesis, in vitro assays were performed in animal models deficient in both adhesion receptors. There was a significantly greater number of IL-3-responsive megakaryocyte progenitors CFU (CFU-MK) and an increase in immature megakaryoblasts in response to IL-6 in the P-selectin-null mice compared with the wild-type controls. Furthermore, P-selectin-null mice showed a greater number of CFU-MK colonies derived from CD34+ cells in response to IL-3 or IL-3 plus stem cell factor. A significant shift in baseline ploidy with a reduction in 8N cells and an increase in 32N cells was also observed in the P-selectin-null mice. Secretion of the inhibitory growth factor TGF-β1 and not TGF-β2 was significantly lower in the supernatants of cultures containing bone marrow cells from P-selectin-deficient mice as compared with those from the wild-type control bone marrow cells. No differences in the responsiveness of murine CFU-MK, immature megakaryocytes, or 5-fluorouracil-selected stem cells to cytokines were observed in E-selectin-null mice as compared with the control mice. These studies indicate that the absence of P-selectin, and not E-selectin, resulted in an altered adhesion environment with subsequent expansion of megakaryocyte progenitors and immature megakaryoblasts, enhanced secretion of TGF-β1, and apparent increased responsiveness to inflammatory cytokines.
Cutting Edge: Localization of the Host Recognition Functions of Complement Factor H at the Carboxyl-Terminal: Implications for Hemolytic Uremic Syndrome
Authors: Pangburn Michael K. 
Published: April 2014

AbstractIncidents of hemolytic uremic syndrome (HUS) include a subset of patients that exhibit mutations in C factor H. These mutations cluster in the C-terminal domains of factor H where previous reports have identified polyanion and C3b-binding sites. In this study, we show that recombinant human factor H with deletions at the C-terminal end of the protein loses the ability to control the spontaneous activation of the alternative C pathway on host-like surfaces. For the pathology of HUS, the findings imply that mutations that disrupt the normal functions of the C-terminal domains prevent host polyanion recognition. The resulting uncontrolled activation of complement on susceptible host tissues appears to be the initiating event behind the acute renal failure of familial HUS patients.
Effect of IL-12 on TNF-α-Mediated Osteoclast Formation in Bone Marrow Cells: Apoptosis Mediated by Fas/Fas Ligand Interaction
Authors: Kitaura Hideki , Nagata Noriko , Fujimura Yuji , Hotokezaka Hitoshi , Yoshida Noriaki , Nakayama Koji 
Published: April 2014

Abstract
Recently, it has been found that differentiation into osteoclasts is induced by TNF-α. In this study, we investigated the effect of IL-12 on TNF-α-mediated osteoclastogenesis. When mouse bone marrow cells were cultured with TNF-α, osteoclast-like cells were formed. When they were cultured with both TNF-α and IL-12, the number of adherent cells in the bone marrow cells decreased in an IL-12 dose-dependent manner. A combination of IL-12 and TNF-α was necessary to induce death of the adherent cells in this culture system. Apoptotic alterations, which were indicated by morphological changes such as cellular atrophy, nuclear and cellular fragmentation, and biochemical changes such as DNA fragmentation, were observed in the adherent cells. Apoptosis of the adherent cells was markedly inhibited by anti-Fas ligand (FasL) Ab. RT-PCR and FACS analyses revealed that TNF-α up-regulated Fas transcription to lead to Fas expression on the surfaces of the adherent cells, whereas IL-12 could not induce Fas on the cells. In contrast, IL-12 induced FasL transcription to lead to FasL expression on the surfaces of nonadherent bone marrow cells, whereas TNF-α could not induce FasL on the cells. These results implied that apoptosis of the adherent cells in bone marrow cells might be caused by interaction between TNF-α-induced Fas on the adherent cells and IL-12-induced FasL on the nonadherent cells.