bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of CCR5 in the Pathogenesis of IL-13-Induced Inflammation and Remodeling
Authors: Ma Bing , Liu Wei , Homer Robert J. , Lee Patty J. , Coyle Anthony J. , Lora Jose M. , Lee Chun Geun , Elias Jack A. 
Published: April 2014

Abstract
IL-13 is a major effector at sites of Th2 inflammation and tissue remodeling. In these locations, it frequently coexists with the CCR5 chemokine receptor and its ligands MIP-1α/CCL3 and MIP-1β/CCL4. We hypothesized that CCR5 induction and activation play important roles in the pathogenesis of IL-13-induced tissue responses. To test this hypothesis, we evaluated the effects of IL-13 on the expression of CCR5 in the murine lung. We also compared the effects of lung-targeted transgenic IL-13 in mice treated with anti-CCR5 or an Ab control and mice with wild-type or null CCR5 loci. These studies demonstrate that IL-13 is a potent stimulator of epithelial cell CCR5 expression. They also demonstrate that CCR5 neutralization or a deficiency of CCR5 significantly decreases IL-13-induced inflammation, alveolar remodeling, structural and inflammatory cell apoptosis, and respiratory failure and death. Lastly, these studies provide mechanistic insights by demonstrating that CCR5 is required for optimal IL-13 stimulation of select chemokines (MIP-1α/CCL3, MIP-1β/CCL4, MCP-1/CCL-2), matrix metalloproteinase-9 and cell death regulators (Fas, TNF, TNFR1, TNFR2, Bid), optimal IL-13 inhibition of α1-antitrypsin, and IL-13-induction of and activation of caspases-3, -8, and-9. Collectively, these studies demonstrate that CCR5 plays a critical role in the pathogenesis of IL-13-induced inflammation and tissue remodeling.
ASC Directs NF-κB Activation by Regulating Receptor Interacting Protein-2 (RIP2) Caspase-1 Interactions
Authors: Sarkar Anasuya , Duncan Michelle , Hart Judy , Hertlein Erin , Guttridge Denis C. , Wewers Mark D. 
Published: April 2014

Abstract
Receptor interacting protein-2 (RIP2) is a caspase recruitment domain (CARD)-containing kinase that interacts with caspase-1 and plays an important role in NF-κB activation. Apoptosis-associated speck-like protein containing a CARD (ASC) is a PYRIN and CARD-containing molecule, important in the induction of apoptosis and caspase-1 activation. Although RIP2 has also been linked to caspase-1 activation, RIP2 knockout animals fail to show a defect in caspase-1-mediated processing of proIL-1β to its active form. Therefore, RIP2 function in binding to caspase-1 remains poorly understood. We hypothesized that caspase-1 may serve as a scaffolding molecule that promotes RIP2 interaction with IκB kinase-γ thus inducing NF-κB activation. We further hypothesized that ASC, which also interacts with caspase-1 via its CARD, may interfere with the caspase-1 RIP2 interaction. In HEK293 cells, ASC induced prominent activation of caspase-1 and proIL-1β processing. RIP2 transient transfection induced transcription of an NF-κB reporter gene. This RIP2-induced NF-κB activity and caspase-1 binding was inhibited in a dose-dependent fashion by ASC. Consistent with a role for caspase-1 as a scaffold for RIP2, caspase-1 knockout macrophages were suppressed in their ability to activate NF-κB, and septic caspase-1 knockout animals produced less IL-6, a functional marker of NF-κB activity. Lastly, THP-1 cells treated with small interfering RNA for ASC decreased their caspase-1 activity while enhancing their NF-κB signal. These data suggest that ASC may direct caspase-1 away from RIP2-mediated NF-κB activation, toward caspase-1-mediated processing of proIL-1β by interfering with the RIP2 caspase-1 interaction.
Substance P Stimulates Cyclooxygenase-2 and Prostaglandin E2 Expression through JAK-STAT Activation in Human Colonic Epithelial Cells
Authors: Koon Hon-Wai , Zhao Dezheng , Zhan Yanai , Rhee Sang Hoon , Moyer Mary P. , Pothoulakis Charalabos 
Published: April 2014

AbstractSubstance P (SP) via its neurokinin-1 receptor (NK-1R) regulates several gastrointestinal functions. We previously reported that NK-1R-mediated chloride secretion in the colon involves formation of PG. PGE2 biosynthesis is controlled by cyclooxygenase-1 (COX-1) and COX-2, whose induction involves the STATs. In this study, we examined whether SP stimulates PGE2 production and COX-2 expression in human nontransformed NCM460 colonocytes stably transfected with the human NK-1R (NCM460-NK-1R cells) and identified the pathways involved in this response. SP exposure time and dose dependently induced an early (1-min) phosphorylation of JAK2, STAT3, and STAT5, followed by COX-2 expression and PGE2 production by 2 h. Pharmacologic experiments showed that PGE2 production is dependent on newly synthesized COX-2, but COX-1 protein. Inhibition of protein kinase Cθ (PKCθ), but not PKCε and PKCδ, significantly reduced SP-induced COX-2 up-regulation, and JAK2, STAT3, and STAT5 phosphorylation. Pharmacological blockade of JAK inhibited SP-induced JAK2, STAT3, and STAT5 phosphorylation; COX-2 expression; and PGE2 production. Transient transfection with JAK2 short-interferring RNA reduced COX-2 promoter activity and JAK2 phosphorylation, while RNA interference of STAT isoforms showed that STAT5 predominantly mediates SP-induced COX-2 promoter activity. Site-directed mutation of STAT binding sites on the COX-2 promoter completely abolished COX-2 promoter activity. Lastly, COX-2 expression was elevated in colon of mice during experimental colitis, and this effect was normalized by administration of the NK-1R antagonist CJ-12,255. Our results demonstrate that SP stimulates COX-2 expression and PGE2 production in human colonocytes via activation of the JAK2-STAT3/5 pathway.
CDR3 Spectratyping Analysis of the TCR Repertoire in Myasthenia Gravis
Authors: Matsumoto Yoh , Matsuo Hidenori , Sakuma Hiroshi , Park Il-Kwon , Tsukada Yukiko , Kohyama Kuniko , Kondo Takayuki , Kotorii Satoshi , Shibuya Noritoshi 
Published: April 2014

AbstractBecause myasthenia gravis (MG) is an autoimmune disease mediated by Abs specific for the acetylcholine receptor, helper T cells play a role in Ab production. In this study, we have performed large-scale cross-sectional and longitudinal TCR studies by CDR3 spectratyping using PBL and thymus tissues from MG patients. We found that there was no preferential usage of any particular TCR β-chains that was identical among MG patients. However, the longitudinal study clearly demonstrated that one or more TCR Vβ expansions persisted frequently in MG patients. Importantly, persistent TCR expansions correlated with clinical severity and high anti-acetylcholine receptor Ab titer. Finally, examinations of T cells expressing CXCR5, i.e., follicular B-helper T cells, revealed that spectratype expansions in MG patients were detected mainly in the CD4+ CXCR5+ T cell populations, whereas CD8+ T cells were the major source of clonal expansion in healthy subjects. These findings suggest that persistent clonal expansions of T cells in MG patients are associated with the development and maintenance of MG. Close examination of pathogenic T cells in MG provides useful information to elucidate the pathogenesis and to estimate the disease status.
Cutting Edge: Lupus Susceptibility Interval Sle3/5 Confers Responsiveness to Prolactin in C57BL/6 Mice
Authors: Peeva Elena , Gonzalez Juana , Hicks Ruthmarie , Diamond Betty 
Published: April 2014

Abstract
Prolactin is of interest in the pathogenesis of systemic lupus erythematosus (SLE) because almost 25% of SLE patients display hyperprolactinemia, and serum prolactin correlates with disease activity in some patients. Furthermore, hyperprolactinemia causes early mortality in lupus-prone mice and induces a lupus-like phenotype in nonspontaneously autoimmune mice. We show here that the immunomodulatory effects of prolactin are genetically determined; hyperprolactinemia breaks B cell tolerance and causes a lupus-like serology in BALB/c mice expressing a transgene encoding the H chain of an anti-DNA Ab but not in C57BL/6 transgenic mice. In C57BL/6 mice that express both the H chain transgene and the lupus susceptibility interval Sle3/5, prolactin induces increased serum titers of anti-DNA Ab and glomerular Ig depositions. The increase in costimulation due to prolactin-mediated up-regulation of both CD40 on B cells and CD40L on T cells would appear to play a central role in lupus induction in this model.
Cutting Edge: Unique T Cells That Recognize Citrullinated Peptides Are a Feature of Protein Immunization
Authors: Ireland Jamie , Herzog Jeremy , Unanue Emil R. 
Published: April 2014

Abstract
Abs against citrullinated proteins are present in patients with rheumatoid arthritis. In this study, we describe a unique cohort of T cells that selectively responded to citrullinated variants of two epitopes of hen egg-white lysozyme, a major and a minor one, bound to the MHC molecule, I-Ak. In addition, we show that when given an intact, unmodified lysozyme protein, dendritic cells and peritoneal macrophages presented citrullinated peptides and stimulated modification-specific T cells. Thus, presentation of citrullinated-peptide-MHC complex is a feature of immune responses to protein Ags.
Suppression of Disease in New Zealand Black/New Zealand White Lupus-Prone Mice by Adoptive Transfer of Ex Vivo Expanded Regulatory T Cells
Authors: Scalapino Kenneth J. , Tang Qizhi , Bluestone Jeffrey A. , Bonyhadi Mark L. , Daikh David I. 
Published: April 2014

AbstractAn increasing number of studies indicate that a subset of CD4+ T cells with regulatory capacity (regulatory T cells; Tregs) can function to control organ-specific autoimmune disease. To determine whether abnormalities of thymic-derived Tregs play a role in systemic lupus erythematosus, we evaluated Treg prevalence and function in (New Zealand Black × New Zealand White)F1 (B/W) lupus-prone mice. To explore the potential of Tregs to suppress disease, we evaluated the effect of adoptive transfer of purified, ex vivo expanded thymic-derived Tregs on the progression of renal disease. We found that although the prevalence of Tregs is reduced in regional lymph nodes and spleen of prediseased B/W mice compared with age-matched non-autoimmune mice, these cells increase in number in older diseased mice. In addition, the ability of these cells to proliferate in vitro was comparable to those purified from non-autoimmune control animals. Purified CD4+CD25+CD62Lhigh B/W Tregs were expanded ex vivo 80-fold, resulting in cells with a stable suppressor phenotype. Adoptive transfer of these exogenously expanded cells reduced the rate at which mice developed renal disease; a second transfer after treated animals had developed proteinuria further slowed the progression of renal disease and significantly improved survival. These studies indicate that thymic-derived Tregs may have a significant role in the control of autoimmunity in lupus-prone B/W mice, and augmentation of these cells may constitute a novel therapeutic approach for systemic lupus erythematosus.
RasGRP1 Transmits Prodifferentiation TCR Signaling That Is Crucial for CD4 T Cell Development
Authors: Priatel John J. , Chen Xiaoxi , Dhanji Salim , Abraham Ninan , Teh Hung-Sia 
Published: April 2014

AbstractTCR signaling plays a governing role in both the survival and differentiation of bipotent double-positive thymocytes into the CD4+ and CD8+ single-positive T cell lineages. A central mediator of this developmental program is the small GTPase Ras, emitting cytoplasmic signals through downstream MAPK pathways and eventually affecting gene expression. TCR signal transduction orchestrates the activation of Ras by integrating at least two Ras-guanyl nucleotide exchange factors, RasGRP1 and Sos. In this study, we have characterized the relationship between RasGRP1 function and its potential roles in promoting ERK activity, cell survival, maturation, and lineage commitment. Investigations on RasGRP1−/− mice expressing a transgenic (Tg) MHC class II-restricted TCR revealed that the development of CD4 T cells expressing this Tg TCR is completely dependent on RasGRP1. Unexpectedly, a small number of functional CD8 single-positive thymocytes expressing the Tg MHC class II-restricted TCR exists in mutant mice. In addition, RasGRP1−/− double-positive thymocytes exhibit marked deficits in TCR-stimulated up-regulation of the positive selection marker CD69 and the antiapoptotic protein Bcl-2, whereas CD5 induction is unaffected. To evaluate the role of RasGRP1 in providing cellular survival signaling, we enforced Bcl-2 expression in RasGRP1−/− thymocytes. These studies demonstrate that RasGRP1 function cannot be fully complemented by Tg Bcl-2 expression. Therefore, we propose that RasGRP1 transmits differentiation signaling critically required for CD4 T cell development.
Phosphorylation of Nonmuscle Myosin Heavy Chain IIA on Ser1917 Is Mediated by Protein Kinase CβII and Coincides with the Onset of Stimulated Degranulation of RBL-2H3 Mast Cells
Authors: Ludowyke Russell I. , Elgundi Zehra , Kranenburg Tanya , Stehn Justine R. , Schmitz-Peiffer Carsten , Hughes William E. , Biden Trevor J. 
Published: April 2014

Abstract
Dynamic remodeling of the actinomyosin cytoskeleton is integral to many biological processes. It is regulated, in part, by myosin phosphorylation. Nonmuscle myosin H chain IIA is phosphorylated by protein kinase C (PKC) on Ser1917. Our aim was to determine the PKC isoform specificity of this phosphorylation event and to evaluate its potential role in regulated secretion. Using an Ab against the phosphorylated form of Ser1917, we show that this site is not phosphorylated in unstimulated RBL-2H3 mast cells. The physiological stimulus, Ag, or the pharmacological activators, PMA plus A23187, induced Ser1917 phosphorylation with a time course coincident with the onset of granule mediator secretion. Dephosphorylation at this site occurred as Ag-stimulated secretion declined from its peak, but dephosphorylation was delayed in cells activated with PMA plus A23187. Phosphate incorporation was also enhanced by PMA alone and by inhibition of protein phosphatase 2A. Gö6976, an inhibitor of conventional PKC isoforms, abolished secretion and Ser1917 phosphorylation with similar dose dependencies consistent with involvement of either PKCα or PKCβ. Phorbol ester-stimulated Ser1917 phosphorylation was reconstituted in HEK-293 cells (which lack endogenous PKCβ) by overexpression of both wild-type and constitutively active PKCβII but not the corresponding PKCβI or PKCα constructs. A similar selectivity for PKCβII overexpression was also observed in MIN6 insulinoma cells infected with recombinant PKC wild-type adenoviruses. Our results implicate PKC-dependent phosphorylation of myosin H chain IIA in the regulation of secretion in mast cells and suggest that Ser1917 phosphorylation might be a marker of PKCβII activation in diverse cell types.
The Thymus Plays a Role in Oral Tolerance in Experimental Autoimmune Encephalomyelitis
Authors: Song Fei , Guan Zhen , Gienapp Ingrid E. , Shawler Todd , Benson Jacqueline , Whitacre Caroline C. 
Published: April 2014

AbstractThe oral administration of myelin proteins has been used for the successful prevention and treatment of experimental autoimmune encephalomyelitis (EAE). We questioned whether the thymus was involved in oral tolerance. In this study, euthymic myelin basic protein (MBP) TCR transgenic mice are protected from EAE when fed MBP but are not protected when thymectomized. Similarly, in a cell transfer system, T cell responses to OVA measured in vivo were suppressed significantly only in the OVA-fed euthymic mice but not in the thymectomized mice. We observed that the absence of the thymus dramatically enhanced the Th1 response. We explored three alternatives to determine the role of the thymus in oral tolerance: 1) as a site for the induction of regulatory T cells; 2) a site for deletion of autoreactive T cells; or 3) a site for the dissemination of naive T cells. We found that Foxp3+CD4+CD25+ T cells are increased in the periphery but not in the thymus after Ag feeding. These CD4+CD25+ T cells also express glucocorticoid-induced TNFR and intracellular CTLA4 and suppress Ag-specific proliferation of CD4+CD25− cells in vitro. The thymus also plays a role in deletion of autoreactive T cells in the periphery following orally administered MBP. However, thymectomy does not result in homeostatic proliferation and the generation of memory cells in this system. Overall, the oral administration of MBP has a profound effect on systemic immune responses, mediated largely by the generation of regulatory T cells that act to prevent or suppress EAE.
Priming Protective CD8 T Cell Immunity by DNA Vaccines Encoding Chimeric, Stress Protein-Capturing Tumor-Associated Antigen
Authors: Schirmbeck Reinhold , Riedl Petra , Kupferschmitt Mark , Wegenka Ursula , Hauser Hansjörg , Rice Jason , Kröger Andrea , Reimann Jörg 
Published: April 2014

AbstractDNA vaccines encoding heat shock protein (hsp)-capturing, chimeric peptides containing antigenic determinants of the tumor-associated Ag (TAA) gp70 (an envelope protein of endogenous retrovirus) primed stable, specific, and tumor-protective CD8 T cell immunity. Expression of gp70 transcripts was detectable in most normal tissues but was particularly striking in some (but not all) tumor cell lines tested (including the adenocarcinoma cell line CT26). An ∼200 residue gp70 fragment or its Ld-binding antigenic AH1 peptide cloned in-frame behind an hsp-capturing (cT272) or noncapturing (T60) N-terminal large SV40 tumor Ag sequence was expressed as either hsp-binding or -nonbinding chimeric Ags. Only hsp-capturing, chimeric fusion proteins were expressed efficiently in transfected cell lines and primed TAA-specific CD8 T cell immunity. This immunity mediated protection in the CT26 and mKSA models. A vaccination strategy based on delivering antigenic, hsp-associated TAA fragments can thus prime protective CD8 T cell immunity even if these TAA are of low intrinsic immunogenicity.
Extracellular Targeting of Endoplasmic Reticulum Chaperone Glucose-Regulated Protein 170 Enhances Tumor Immunity to a Poorly Immunogenic Melanoma
Authors: Wang Xiang-Yang , Arnouk Hilal , Chen Xing , Kazim Latif , Repasky Elizabeth A. , Subjeck John R. 
Published: April 2014

AbstractWe have demonstrated previously that immunization with tumor-derived endoplasmic reticulum (ER) chaperone glucose-regulated protein 170 (grp170) elicits potent antitumor immunity. In the present study, we determine the impact of extracellular targeting grp170 by molecular engineering on tumor immunogenicity and potential use of grp170-secreting tumor cells as a cancer vaccine. grp170 depleted of ER retention sequence “KNDEL,” when secreted by B16 tumor cells, maintained its highly efficient chaperoning activities and was significantly superior to both hsp70 and gp96. The continued secretion of grp170 dramatically reduced the tumorigenicity of B16 tumor cells in vivo, although the modification did not alter its transformation phenotype and cell growth rate. C57BL/6 mice that rejected grp170-secreting B16 tumor cells (B16-sgrp170) developed a strong CTL response recognizing melanocyte differentiation Ag TRP2 and were resistant to subsequent tumor challenge. B16-sgrp170 cells also stimulated the production of proinflammatory cytokines by cocultured dendritic cells. Depletion studies in vivo indicate that NK cells play a primary role in elimination of viable B16-sgrp170 tumor cells inoculated into the animals, whereas both NK cells and CD8+ T cells are required for a long-term protection against wild-type B16 tumor challenge. Both the secreted and endogenous grp170, when purified from the B16 tumor, exhibited potent tumor-protective activities. However, the B16-sgrp170 cell appears to be more effective than tumor-derived grp170. Thus, molecular engineering of tumor cell to release the largest ER chaperone grp170 is capable of eliciting innate as well as adaptive immune responses, which may provide an effective cell-based vaccination approach for cancer immunotherapy.
Pertussis Toxin Reduces the Number of Splenic Foxp3+ Regulatory T Cells
Authors: Cassan Cécile , Piaggio Eliane , Zappulla Jacques P. , Mars Lennart T. , Couturier Nicolas , Bucciarelli Florence , Desbois Sabine , Bauer Jan , Gonzalez-Dunia Daniel , Liblau Roland S. 
Published: April 2014

AbstractPertussis toxin (PTx) is a bacterial toxin used to enhance the severity of experimental autoimmune diseases such as experimental autoimmune encephalomyelitis. It is known to promote permeabilization of the blood-brain barrier, maturation of APC, activation of autoreactive lymphocytes and alteration of lymphocyte migration. In this study, we show that i.v. injection of PTx in mice induces a decrease in the number of splenic CD4+CD25+ regulatory T cells (Treg cells). Furthermore, PTx not only induces a depletion of the dominant CD4+CD25+Foxp3+ subpopulation of splenic Treg cells, but also reduces to a similar extent the CD4+CD25−Foxp3+ subpopulation. On a per cell basis, the suppressive properties of the remaining Treg cells are not modified by PTx treatment. The reduction in splenic Treg cells is associated with preferential migration of these cells to the liver. Additionally, Treg cells exhibit a high sensitivity to PTx-mediated apoptosis in vitro. Finally, in vivo depletion of Treg cells by injection of an anti-CD25 Ab, and PTx treatment, present synergistic experimental autoimmune encephalomyelitis exacerbating effects. Therefore, we identify a new effect of PTx and provide an additional illustration of the influence of microbial components on the immune system affecting the balance between tolerance, inflammation and autoimmunity.
A Critical Role for Prostaglandin E2 in Podosome Dissolution and Induction of High-Speed Migration during Dendritic Cell Maturation
Authors: van Helden Suzanne F. G. , Krooshoop Daniëlle J. E. B. , Broers Karin C. M. , Raymakers Reinier A. P. , Figdor Carl G. , van Leeuwen Frank N. 
Published: April 2014

AbstractDendritic cells (DCs) are professional APCs of the immune system that play a key role in regulating T cell-based immunity. The capacity of DCs to activate T cells depends on their maturation state as well as their ability to migrate to the T cell areas of draining lymph nodes. In this study, we investigated the effects of DC maturation stimuli on the actin cytoskeleton and β1 integrin-dependent adhesion and migration. Podosomes, specialized adhesion structures found in immature monocyte-derived DCs as well as myeloid DCs, rapidly dissolve in response to maturation stimuli such as TNF-α and PGE2, whereas the TLR agonist LPS induces podosome dissolution only after a long lag time. We demonstrate that LPS-mediated podosome disassembly as well as the onset of high-speed DC migration are dependent on the production of PGs by the DCs. Moreover, both of these processes are inhibited by Ab-induced activation of β1 integrins. Together, these results show that maturation-induced podosome dissolution and loss of α5β1 integrin activity allow human DCs to undergo the transition from an adhesive to a highly migratory phenotype.
CXCL16 Influences the Nature and Specificity of CpG-Induced Immune Activation
Authors: Gursel Mayda , Gursel Ihsan , Mostowski Howard S. , Klinman Dennis M. 
Published: April 2014

Abstract
Unmethylated CpG motifs are present at high frequency in bacterial DNA. They provide a danger signal to the mammalian immune system that triggers a protective immune response characterized by the production of Th1 and proinflammatory cytokines and chemokines. Although the recognition of CpG DNA by B cells and plasmacytoid dendritic cells is mediated by TLR 9, these cell types differ in their ability to bind and respond to structurally distinct classes of CpG oligonucleotides. This work establishes that CXCL16, a membrane-bound scavenger receptor, influences the uptake, subcellular localization, and cytokine profile induced by D oligonucleotides. This is the first example of a surface receptor modifying the cellular specificity and nature of the immune response mediated by an intracellular TLR.