bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Role for Cathepsin L and Cathepsin S in Peptide Generation for MHC Class II Presentation
Authors: Hsieh Chyi-Song , deRoos Paul , Honey Karen , Beers Courtney , Rudensky Alexander Y. 
Published: April 2014

AbstractThe enzymes that degrade proteins to peptides for presentation on MHC class II molecules are poorly understood. The cysteinal lysosomal proteases, cathepsin L (CL) and cathepsin S (CS), have been shown to process invariant chain, thereby facilitating MHC class II maturation. However, their role in Ag processing is not established. To examine this issue, we generated embryonic fibroblast lines that express CL, CS, or neither. Expression of CL or CS mediates efficient degradation of invariant chain as expected. Ag presentation was evaluated using T cell hybridoma assays as well as mass spectroscopic analysis of peptides eluted from MHC class II molecules. Interestingly, we found that the majority of peptides are presented regardless of CL or CS expression, although these proteases often alter the relative levels of the peptides. However, for a subset of Ags, epitope generation is critically regulated by CL or CS. This result suggests that these cysteinal proteases participate in Ag processing and generate qualitative and quantitative differences in the peptide repertoires displayed by MHC class II molecules.
L-Selectin Is Not Required for T Cell-Mediated Autoimmune Diabetes
Authors: Friedline Randall H. , Wong Carmen P. , Steeber Douglas A. , Tedder Thomas F. , Tisch Roland 
Published: April 2014

AbstractAdministration of anti-L-selectin (CD62L) mAb to neonatal nonobese diabetic (NOD) mice mediates long term protection against the development of insulitis and overt diabetes. These results suggested that CD62L has a key role in the general function of β cell-specific T cells. To further examine the role of CD62L in the development of type 1 diabetes, NOD mice lacking CD62L were established. The onset and frequency of overt diabetes were equivalent among CD62L+/+, CD62L+/−, and CD62L−/− NOD littermates. Furthermore, patterns of T cell activation, migration, and β cell-specific reactivity were similar in NOD mice of all three genotypes. Adoptive transfer experiments with CD62L−/− CD4+ T cells prepared from BDC2.5 TCR transgenic mice revealed no apparent defects in migration to pancreatic lymph nodes, proliferation in response to β cell Ag, or induction of diabetes in NOD.scid recipients. In conclusion, CD62L expression is not essential for the development of type 1 diabetes in NOD mice.
Differential In Vivo Persistence of Two Subsets of Memory Phenotype CD8 T Cells Defined by CD44 and CD122 Expression Levels
Authors: Walzer Thierry , Arpin Christophe , Beloeil Laurent , Marvel Jacqueline 
Published: April 2014

AbstractThe existence of distinct subsets of memory CD8 T cells with different characteristics is now well established. In this work, we describe two subsets of mouse CD8 T cells with memory characteristics that coexist in primed thymectomized TCR-transgenic F5 mice and that share some properties with the human central and effector memory cells. The first subset corresponds to CD8 T cells generated following nucleoprotein 68 peptide priming which are CD44intCD122−nucleoprotein 68/H-2Db tetramer+ and express high levels of CCR7 mRNA. In contrast, CD8 T cells in the second subset are CD44highCD122+, are heterogeneous in terms of Ag specificity, and express low levels of CCR7 mRNA. We have studied the functional characteristics and the persistence of these two subsets in thymectomized mice. CD44int CD8 T cells persist like naive cells; i.e., they are slowly lost with time. However, surviving cells maintain their phenotype and memory characteristics for the entire life span of the animal. In contrast, CD44high CD8 T cells are persistent and accumulate in thymectomized but not euthymic mice. This is correlated with an increased in vivo proliferative and survival potential of these cells. These results show that acquisition of enhanced functional characteristics and long-term persistence by memory T cells are independent. This may have important consequences for the design of specific vaccine.
T Cell Immunity to Lymphoma Following Treatment with Anti-CD40 Monoclonal Antibody
Authors: Tutt Alison L. , O’Brien Lyn , Hussain Akmal , Crowther Graham R. , French Ruth R. , Glennie Martin J. 
Published: April 2014

AbstractIn this study we demonstrate that treatment with anti-CD40 mAb eradicates a range of mouse lymphomas (BCL1, A31, A20, and EL4), but only when used against i.v. tumor doses in excess of 107 cells. Only partial protection was seen against smaller tumor loads. We saw no evidence that anti-CD40 mAb changed the phenotype of the lymphomas or inhibited their growth in the initial period following treatment, but it did result in a rapid expansion of cytotoxic CD8+ cells that was able to clear the neoplastic disease and provide long-term protection against tumor rechallenge. The CTL responses were blocked by mAb against a range of coreceptors and cytokines, including CD8, B7-1, B7-2, LFA-1, and IFN-γ, but not CD4 or CTLA-4, indicating the presence of a conventional cellular Th1 response. Furthermore, we found evidence of cross-recognition between lymphomas (BCL1 and A20) as measured by cytotoxicity and IFN-γ responses in vitro and using tumor rechallenge experiments, suggesting common target Ags. Finally, although anti-CD40 was shown to stimulate NK cell killing, we could find no role for these cells in controlling tumor growth. These data underline the ability of anti-CD40 mAb to potentiate CTL responses and the potency of cellular immunity in eradicating large quantities of syngeneic tumor.
CD40 Ligand Functions Non-Cell Autonomously to Promote Deletion of Self-Reactive Thymocytes
Authors: Williams Joy A. , Sharrow Susan O. , Adams Anthony J. , Hodes Richard J. 
Published: April 2014

AbstractCD40 ligand (CD40L)-deficient mice have been shown to have a defect in negative selection of self-reactive T cells during thymic development. However, the mechanism by which CD40L promotes deletion of autoreactive thymocytes has not yet been elucidated. We have studied negative selection in response to endogenous superantigens in CD40L-deficient mice and, consistent with previous reports, have found a defect in negative selection in these mice. To test the requirement for expression of CD40L on T cells undergoing negative selection, we have generated chimeric mice in which CD40L wild-type and CD40L-deficient thymocytes coexist. We find that both CD40L wild-type and CD40L-deficient thymocytes undergo equivalent and efficient negative selection when these populations coexist in chimeric mice. These results indicate that CD40L can function in a non-cell-autonomous manner during negative selection. Deletion of superantigen-reactive thymocytes was normal in B7-1/B7-2 double-knockout mice, indicating that CD40-CD40L-dependent negative selection is not solely mediated by B7 up-regulation and facilitation of B7-dependent T cell signaling. Finally, although the absence of CD40-CD40L interactions impairs negative selection of autoreactive CD4+ and CD8+ cells during thymic development, we find that self-reactive T cells are deleted in the mature CD4+ population through a CD40L-independent pathway.
Impact of Antigen Presentation on TCR Modulation and Cytokine Release: Implications for Detection and Sorting of Antigen-Specific CD8+ T Cells Using HLA-A2 Wild-Type or HLA-A2 Mutant Tetrameric Complexes
Authors: Jäger Elke , Salter Russell , Castelli Chiara , Höhn Hanni , Freitag Kirsten , Karbach Julia , Neukirch Claudia , Necker Antje , Knuth Alexander , Maeurer Markus J. 
Published: April 2014

Abstract
Soluble MHC class I molecules loaded with antigenic peptides are available either to detect and to enumerate or, alternatively, to sort and expand MHC class I-restricted and peptide-reactive T cells. A defined number of MHC class I/peptide complexes can now be implemented to measure T cell responses induced upon Ag-specific stimulation, including CD3/CD8/ζ-chain down-regulation, pattern, and quantity of cytokine secretion. As a paradigm, we analyzed the reactivity of a Melan-A/MART-1-specific and HLA-A2-restricted CD8+ T cell clone to either soluble or solid-phase presented peptides, including the naturally processed and presented Melan-A/MART-1 peptide AAGIGILTV or the peptide analog ELAGIGILTV presented either by the HLA-A2 wild-type (wt) or mutant (alanine→valine aa 245) MHC class I molecule, which reduces engagement of the CD8 molecule with the HLA-A2 heavy chain. Soluble MHC class I complexes were used as either monomeric or tetrameric complexes. Soluble monomeric MHC class I complexes, loaded with the Melan-A/MART-1 peptide, resulted in CD3/CD8 and TCR ζ-chain down-regulation, but did not induce measurable cytokine release. In general, differences pertaining to CD3/CD8/ζ-chain regulation and cytokine release, including IL-2, IFN-γ, and GM-CSF, were associated with 1) the format of Ag presentation (monomeric vs tetrameric MHC class I complexes), 2) wt vs mutant HLA-A2 molecules, and 3) the target Ag (wt vs analog peptide). These differences are to be considered if T cells are exposed to recombinant MHC class I Ags loaded with peptides implemented for detection, activation, or sorting of Ag-specific T cells.
A Role for CCR9 in T Lymphocyte Development and Migration
Authors: Uehara Shoji , Grinberg Alexander , Farber Joshua M. , Love Paul E. 
Published: April 2014

AbstractCCR9 mediates chemotaxis in response to CCL25/thymus-expressed chemokine and is selectively expressed on T cells in the thymus and small intestine. To investigate the role of CCR9 in T cell development, the CCR9 gene was disrupted by homologous recombination. B cell development, thymic αβ-T cell development, and thymocyte selection appeared unimpaired in adult CCR9-deficient (CCR9−/−) mice. However, competitive transplantation experiments revealed that bone marrow from CCR9−/− mice was less efficient at repopulating the thymus of lethally irradiated Rag-1−/− mice than bone marrow from littermate CCR9+/+ mice. CCR9−/− mice had increased numbers of peripheral γδ-T cells but reduced numbers of γδTCR+ and CD8αβ+αβTCR+ intraepithelial lymphocytes in the small intestine. Thus, CCR9 plays an important, although not indispensable, role in regulating the development and/or migration of both αβ− and γδ− T lymphocytes.
ThePmed1Gene Promoter of Human FcγRIIIA Can Function as a NK/T Cell-Specific Restriction Element, Which Involves Binding of Sp1 Transcription Factor
Authors: Heusohn Frank , Wirries Gundula , Schmidt Reinhold E. , Gessner J. Engelbert 
Published: April 2014

AbstractThe low-affinity receptor for IgG (human FcγRIIIA) is selectively expressed by a subset of T lymphocytes, NK cells, and macrophages. To understand the mechanisms underlying this pattern of cell type-specific expression, we initially identified alternative promoters, Pmed1/2 and Pprox, in the 5′ end of the FcγRIIIA gene. In this study, we focused on the Pmed1 promoter and demonstrated this 93-bp region to be highly specific in governing restriction to NK/T cell lines. This property of Pmed1 is context independent and can extend to a disparate promoter. Deletion analysis defined a contribution of two separate elements located to the 5′ 21-bp (−942/−922) and 3′ 72-bp (−921/−850) regions of Pmed1 in conferring NK/T cell specificity. The 5′ part of Pmed1 contains binding sites for Sp1 and NK element-recognizing factors and substitution mapping studies revealed a critical requirement of the Sp1-I site. The importance of Sp1 protein to regulate maximal Pmed1 promoter activity was further established by EMSAs and cotransfection experiments in Sp1-null Drosophila SL2 cells. Our data suggest that Sp1 can contribute, in part, to NK/T cell restriction and further indicate that the FcγRIIIA Pmed1 sequence might be useful to direct the NK/T cell-specific expression of heterologous genes.
Eotaxin/CCL11 Suppresses IL-8/CXCL8 Secretion from Human Dermal Microvascular Endothelial Cells
Authors: Cheng Sara S. , Lukacs Nicholas W. , Kunkel Steven L. 
Published: April 2014

AbstractThe CC chemokine eotaxin/CCL11 is known to bind to the receptor CCR3 on eosinophils and Th2-type lymphocytes. In this study, we demonstrate that CCR3 is expressed on a subpopulation of primary human dermal microvascular endothelial cells and is up-regulated by TNF-α. We found that incubation of human dermal microvascular endothelial cells with recombinant eotaxin/CCL11 suppresses TNF-α-induced production of the neutrophil-specific chemokine IL-8/CXCL8. The eotaxin/CCL11-suppressive effect on endothelial cells was not seen on IL-1β-induced IL-8/CXCL8 release. Eotaxin/CCL11 showed no effect on TNF-α-induced up-regulation of growth-related oncogene-α or IFN-γ-inducible protein-10, two other CXC chemokines tested, and did not affect production of the CC chemokines monocyte chemoattractant protein-1/CCL2 and RANTES/CCL5, or the adhesion molecules ICAM-1 and E-selectin. These results suggest that eotaxin/CXCL11 is not effecting a general suppression of TNF-αR levels or signal transduction. Suppression of IL-8/CXCL8 was abrogated in the presence of anti-CCR3 mAb, pertussis toxin, and wortmannin, indicating it was mediated by the CCR3 receptor, Gi proteins, and phosphatidylinositol 3-kinase signaling. Eotaxin/CCL11 decreased steady state levels of IL-8/CXCL8 mRNA in TNF-α-stimulated cells, an effect mediated in part by an acceleration of IL-8 mRNA decay. Eotaxin/CCL11 may down-regulate production of the neutrophil chemoattractant IL-8/CXCL8 by endothelial cells in vivo, acting as a negative regulator of neutrophil recruitment. This may play an important biological role in the prevention of overzealous inflammatory responses, aiding in the resolution of acute inflammation or transition from neutrophilic to mononuclear/eosinophilic inflammation.
Dendritic Cells Pulsed with Fungal RNA Induce Protective Immunity toCandida albicansin Hematopoietic Transplantation
Authors: Bacci Angela , Montagnoli Claudia , Perruccio Katia , Bozza Silvia , Gaziano Roberta , Pitzurra Lucia , Velardi Andrea , d’Ostiani Cristiana Fe’ , Cutler Jim E. , Romani Luigina 
Published: April 2014

AbstractImmature myeloid dendritic cells (DC) phagocytose yeasts and hyphae of the fungus Candida albicans and induce different Th cell responses to the fungus. Ingestion of yeasts activates DC for production of IL-12 and Th1 priming, while ingestion of hyphae induces IL-4 production and Th2 priming. In vivo, generation of antifungal protective immunity is induced upon injection of DC ex vivo pulsed with Candida yeasts but not hyphae. In the present study we sought to determine the functional activity of DC transfected with yeast or hyphal RNA. It was found that DC, from either spleens or bone marrow, transfected with yeast, but not hyphal, RNA 1) express fungal mannoproteins on their surface; 2) undergo functional maturation, as revealed by the up-regulated expression of MHC class II Ags and costimulatory molecules; 3) produce IL-12 but no IL-4; 4) are capable of inducing Th1-dependent antifungal resistance when delivered s.c. in vivo in nontransplanted mice; and 5) provide protection against the fungus in allogeneic bone marrow-transplanted mice, by accelerating the functional recovery of Candida-specific IFN-γ-producing CD4+ donor lymphocytes. These results indicate the efficacy of DC pulsed with Candida yeasts or yeast RNA as fungal vaccines and point to the potential use of RNA-transfected DC as anti-infective vaccines in conditions that negate the use of attenuated microorganisms or in the case of poor availability of protective Ags.
Protection Against Influenza Virus Infection in Polymeric Ig Receptor Knockout Mice Immunized Intranasally with Adjuvant-Combined Vaccines
Authors: Asahi Yasuko , Yoshikawa Tomoki , Watanabe Izumi , Iwasaki Takuya , Hasegawa Hideki , Sato Yuko , Shimada Shin-ichiro , Nanno Masanobu , Matsuoka Yoshiaki , Ohwaki Makoto , Iwakura Yoichiro , Suzuki Yujiro , Aizawa Chikara , Sata Tetutaro , Kurata Takeshi , Tamura Shin-ichi 
Published: April 2014

AbstractThe role of secretory IgA in conferring cross-protective immunity was examined in polymeric (p)IgR knockout (KO) mice immunized intranasally with different inactivated vaccines prepared from A/PR/8/34 (H1N1), A/Yamagata/120/86 (H1N1), A/Beijing/262/95 (H1N1), and B/Ibaraki/2/85 viruses and infected with the A/PR/8/34 virus in the upper respiratory tract (RT)-restricting volume. In wild-type mice, immunization with A/PR/8/34 or its variant (A/Yamagata/120/86 and A/Beijing/262/95) vaccines conferred complete protection or partial cross-protection against infection, while the B-type virus vaccine failed to provide protection. The protection or cross-protection was accompanied by an increase in the nasal A/PR/8/34 hemagglutinin-reactive IgA concentration, which was estimated to be &gt;30 times the serum IgA concentration and much higher than the nasal IgG concentration. In contrast, the blockade of transepithelial transport of dimeric IgA in pIgR-KO mice reduced the degree of protection or cross-protection, in parallel with the marked increase in serum IgA concentration and the decrease in nasal IgA concentration (∼20 and 0.3 times those in wild-type mice, respectively). The degree of the reduction of protection or cross-protection was moderately reversed by the low but non-negligible level of nasal IgA, transudates from the accumulated serum IgA. These results, together with the absence of the IgA-dependent cross-protection in the lower RT and the unaltered level of nasal or serum IgG in wild-type and pIgR-KO mice, confirm that the actively secreted IgA plays an important role in cross-protection against variant virus infection in the upper RT, which cannot be substituted by serum IgG.
Heat Shock Proteins gp96 and hsp70 Activate the Release of Nitric Oxide by APCs
Authors: Panjwani Naveed N. , Popova Lana , Srivastava Pramod K. 
Published: April 2014

AbstractNO is a cytotoxic and immunomodulatory cytokine produced by macrophages and dendritic cells. We show that stimulation of murine and human macrophages with the heat shock proteins gp96 and hsp70 results in induction of inducible NO synthase and the production of NO. The release of NO by monocytes exposed to hsp60 has been documented previously. Immature, but not mature, dendritic cells respond in the same manner. The activity of heat shock proteins is relatively unaffected by an antagonist of LPS, and is abrogated by heat denaturation. Macrophages have been shown previously to produce NO in response to stimulation with IFN-γ; stimulation of macrophages with mixtures of IFN-γ and gp96 or hsp70 leads to a synergistic production of NO. The present observations extend the roles of these heat shock proteins in innate immune responses to another potent and highly conserved function of APC.
Interaction of Antibodies to Proteinase 3 (Classic Anti-Neutrophil Cytoplasmic Antibody) with Human Renal Tubular Epithelial Cells: Impact on Signaling Events and Inflammatory Mediator Generation
Authors: Hattar Katja , Grandel Ulrich , Bickenbach Annette , Schwarting Andreas , Mayet Werner-Johannes , Bux Jürgen , Jessen Sönke , Fischer Claus , Seeger Werner , Grimminger Friedrich , Sibelius Ulf 
Published: April 2014

Abstract
Among the anti-neutrophil cytoplasmic Abs (ANCA), those targeting proteinase 3 (PR3) have a high sensitivity and specificity for Wegener’s granulomatosis (WG). A pathogenetic role for these autoantibodies has been proposed due to their capacity of activating neutrophils in vitro. Recently, PR3 was also detected in human renal tubular epithelial cells (TEC). In the present study, the effect of murine monoclonal anti-PR3 Abs (anti-PR3) and purified c-ANCA targeting PR3 from WG serum on isolated human renal tubular cell signaling and inflammatory mediator release was characterized. Priming of TEC with TNF-α resulted in surface expression of PR3, as quantified in immunofluorescence studies and by flow cytometry. Moreover, PR3 was immunoprecipitated on surface-labeled TEC. Primed TEC responded to anti-PR3 with a dose- and time-dependent activation of phosphoinositide hydrolysis, resulting in a remarkable accumulation of inositolphosphates. Control IgG was entirely ineffective, whereas PR3-ANCA reproduced the phosphoinositide response. The signaling response was accompanied by a pronounced release of superoxidanion into the cell supernatant. Moreover, large amounts of PGE2 and, to a lesser extent, of thromboxane B2, the stable metabolite of TxA2, were secreted from anti-PR3-stimulated TEC. In parallel, a rise in intracellular cAMP levels was observed, which was blocked by the cyclooxygenase inhibitor indomethacin. We conclude that anti-PR3 Abs directly target renal TECs, thereby provoking pronounced activation of the phosphoinositide-related signal transduction pathway. Associated metabolic events such as the release of reactive oxygen species and lipid mediators may directly contribute to the development of renal lesions and loss of kidney function in WG.
Murine Sclerodermatous Graft-Versus-Host Disease, a Model for Human Scleroderma: Cutaneous Cytokines, Chemokines, and Immune Cell Activation
Authors: Zhang Yan , McCormick Laura L. , Desai Snehal R. , Wu Caiyun , Gilliam Anita C. 
Published: April 2014

AbstractMurine sclerodermatous graft-vs-host disease (Scl GVHD) models human scleroderma, with prominent skin thickening, lung fibrosis, and up-regulation of cutaneous collagen mRNA. Fibrosis in Scl GVHD may be driven by infiltrating TGF-β1-producing mononuclear cells. Here we characterize the origin and types of those cutaneous effector cells, the cytokine and chemokine environments, and the effects of anti-TGF-β Ab on skin fibrosis, immune cell activation markers, and collagen and cytokine synthesis. Donor cells infiltrating skin in Scl GVHD increase significantly at early time points post-transplantation and are detectable by PCR analysis of Y-chromosome sequences when female mice are transplanted with male cells. Cutaneous monocyte/macrophages and T cells are the most numerous cells in Scl GVHD compared with syngeneic controls. These immune cells up-regulate activation markers (MHC class II I-Ad molecules and class A scavenger receptors), suggesting Ag presentation by cutaneous macrophages in early fibrosing disease. Early elevated cutaneous mRNA expression of TGF-β1, but not TGF-β2 or TGF-β3, and elevated C-C chemokines macrophage chemoattractant protein-1, macrophage inflammatory protein-1α, and RANTES precede subsequent skin and lung fibrosis. Therefore, TGF-β1-producing donor mononuclear cells may be critical effector cells, and C-C chemokines may play important roles in the initiation of Scl GVHD. Abs to TGF-β prevent Scl GVHD by effectively blocking the influx of monocyte/macrophages and T cells into skin and by abrogating up-regulation of TGF-β1, thereby preventing new collagen synthesis. The Scl GVHD model is valuable for testing new interventions in early fibrosing diseases, and chemokines may be new potential targets in scleroderma.