bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improving Vaccine Potency Through Intercellular Spreading and Enhanced MHC Class I Presentation of Antigen
Authors: Hung Chien-Fu , Cheng Wen-Fang , Chai Chee-Yin , Hsu Keng-Fu , He Liangmei , Ling Morris , Wu T.-C. 
Published: April 2014

Abstract
The potency of naked DNA vaccines is limited by their inability to amplify and spread in vivo. VP22, a HSV-1 protein, has demonstrated the remarkable property of intercellular transport and may thus provide a unique approach for enhancing vaccine potency. Therefore, we created a novel fusion of VP22 with a model Ag, human papillomavirus type 16 E7, in a DNA vaccine that generated enhanced spreading and MHC class I presentation of Ag. These properties led to a dramatic increase in the number of E7-specific CD8+ T cell precursors in vaccinated mice (around 50-fold) and converted a less effective DNA vaccine into one with significant potency against E7-expressing tumors. In comparison, nonspreading VP221–267 mutants failed to enhance vaccine potency. Our data indicated that the potency of DNA vaccines may be dramatically improved through intercellular spreading and enhanced MHC class I presentation of Ag.
Salmonella Pathogenicity Island 2-Encoded Type III Secretion System Mediates Exclusion of NADPH Oxidase Assembly from the Phagosomal Membrane
Authors: Gallois Annabelle , Klein Joanna R. , Allen Lee-Ann H. , Jones Bradley D. , Nauseef William M. 
Published: April 2014

Abstract
Salmonella typhimurium requires a type III secretion system encoded by pathogenicity island (SPI)-2 to survive and proliferate within macrophages. This survival implies that S. typhimurium avoids or withstands bactericidal events targeted to the microbe-containing vacuole, which include intraphagosomal production of reactive oxygen species (ROS), phagosomal acidification, and delivery of hydrolytic enzymes to the phagosome via fusion with lysosomes. Recent evidence suggests that S. typhimurium alters ROS production by murine macrophages in an SPI-2-dependent manner. To gain insights into the mechanism by which S. typhimurium inhibits intraphagosomal ROS production, we analyzed the subcellular distribution of NADPH oxidase components during infection of human monocyte-derived macrophages by wild-type (WT) or several SPI-2 mutant strains of S. typhimurium. We found that the membrane component of the NADPH oxidase, flavocytochrome b558, was actively excluded or rapidly removed from the phagosomal membrane of WT-infected monocyte-derived macrophages, thereby preventing assembly of the NADPH oxidase complex and intraphagosomal production of superoxide anion. In contrast, the NADPH oxidase assembled on and generated ROS in phagosomes containing SPI-2 mutant S. typhimurium. Subversion of NADPH oxidase assembly by S. typhimurium was accompanied by increased bacterial replication relative to that of SPI-2 mutant strains, suggesting that the ability of WT S. typhimurium to prevent NADPH oxidase assembly at the phagosomal membrane represents an important virulence factor influencing its intracellular survival.
Expression of Stromal-Derived Factor-1 Is Decreased by IL-1 and TNF and in Dermal Wound Healing
Authors: Fedyk Eric R. , Jones Dan , Critchley Hilary O. D. , Phipps Richard P. , Blieden Timothy M. , Springer Timothy A. 
Published: April 2014

Abstract
Stromal-derived factor-1 (SDF-1) is a CXC chemokine that is believed to be constitutively expressed by stromal cells of numerous tissues. In this report, we demonstrate that dermal fibroblasts and vessels of noninflamed tissues express SDF-1. Unexpectedly, we found that expression of SDF-1 is regulated by inflammation. Expression of SDF-1 by primary cultures of human gingival fibroblasts is potently inhibited by activated macrophages via secretion of IL-1α and TNF-α. Levels of SDF-1 mRNA also decrease in acutely inflamed mouse dermal wounds. We propose that SDF-1 functions as a homeostatic regulator of tissue remodeling, whose expression stabilizes existing dermal architecture.
Combinatorial Model of Chemokine Involvement in Glomerular Monocyte Recruitment: Role of CXC Chemokine Receptor 2 in Infiltration During Nephrotoxic Nephritis
Authors: Zernecke Alma , Weber Kim S. C. , Erwig Lars P. , Kluth David C. , Schröppel Bernd , Rees Andrew J. , Weber Christian 
Published: April 2014

Abstract
A sequential model involving chemokines has been proposed for leukocyte extravasation into areas of inflammation; however, site-specific aspects remain to be elucidated. Hence, we studied the role of chemokines produced by mesangial (MC) or glomerular endothelial cells (GEC) and their receptors in glomerular recruitment of monocytes. Stimulation of MC with TNF-α up-regulated mRNA and protein of CC and CXC chemokines but not constitutive expression of the CX3C chemokine fractalkine. While growth-related activity (GRO)-α was immobilized to MC proteoglycans, monocyte chemotactic protein (MCP)-1 was secreted into the soluble phase. Firm adhesion and sequestration of monocytes on activated MC was supported by the GRO-α receptor CXCR2 and to a lesser extent by CX3CR, whereas the MCP-1 receptor CCR2 contributed to their transendothelial chemotaxis toward activated MC. In contrast, fractalkine mRNA and protein was induced by TNF-α in transformed rat GEC, and both CXCR2 and CX3CR mediated monocyte arrest on GEC in shear flow. The relevance of these mechanisms was confirmed in a rat nephrotoxic nephritis model where acute glomerular macrophage recruitment was profoundly inhibited by blocking CXCR2 or CCR2. In conclusion, our results epitomize a combinatorial model in which chemokines play specialized roles in driving glomerular monocyte recruitment and emphasize an important role for CXCR2 in macrophage infiltration during early phases of nephrotoxic nephritis.
Eosinophils Are a Major Source of Nitric Oxide-Derived Oxidants in Severe Asthma: Characterization of Pathways Available to Eosinophils for Generating Reactive Nitrogen Species
Authors: MacPherson Jennifer C. , Comhair Suzy A. A. , Erzurum Serpil C. , Klein Dennis F. , Lipscomb Mary F. , Kavuru Mani S. , Samoszuk Michael K. , Hazen Stanley L. 
Published: April 2014

Abstract
Eosinophil recruitment and enhanced production of NO are characteristic features of asthma. However, neither the ability of eosinophils to generate NO-derived oxidants nor their role in nitration of targets during asthma is established. Using gas chromatography-mass spectrometry we demonstrate a 10-fold increase in 3-nitrotyrosine (NO2Y) content, a global marker of protein modification by reactive nitrogen species, in proteins recovered from bronchoalveolar lavage of severe asthmatic patients (480 ± 198 μmol/mol tyrosine; n = 11) compared with nonasthmatic subjects (52.5 ± 40.7 μmol/mol tyrosine; n = 12). Parallel gas chromatography-mass spectrometry analyses of bronchoalveolar lavage proteins for 3-bromotyrosine (BrY) and 3-chlorotyrosine (ClY), selective markers of eosinophil peroxidase (EPO)- and myeloperoxidase-catalyzed oxidation, respectively, demonstrated a dramatic preferential formation of BrY in asthmatic (1093 ± 457 μmol BrY/mol tyrosine; 161 ± 88 μmol ClY/mol tyrosine; n = 11 each) compared with nonasthmatic subjects (13 ± 14.5 μmol BrY/mol tyrosine; 65 ± 69 μmol ClY/mol tyrosine; n = 12 each). Bronchial tissue from individuals who died of asthma demonstrated the most intense anti-NO2Y immunostaining in epitopes that colocalized with eosinophils. Although eosinophils from normal subjects failed to generate detectable levels of NO, NO2−, NO3−, or NO2Y, tyrosine nitration was promoted by eosinophils activated either in the presence of physiological levels of NO2− or an exogenous NO source. At low, but not high (e.g., &gt;2 μM/min), rates of NO flux, EPO inhibitors and catalase markedly attenuated aromatic nitration. These results identify eosinophils as a major source of oxidants during asthma. They also demonstrate that eosinophils use distinct mechanisms for generating NO-derived oxidants and identify EPO as an enzymatic source of nitrating intermediates in eosinophils.
Rapid Depletion of Peripheral Antigen-Specific T Cells in TCR-Transgenic Mice After Oral Administration of Myelin Basic Protein
Authors: Meyer Abbie L. , Benson Jacqueline , Song Fei , Javed Najma , Gienapp Ingrid E. , Goverman Joan , Brabb Thea A. , Hood Leroy , Whitacre Caroline C. 
Published: April 2014

Abstract
In myelin basic protein (MBP)-specific TCR-transgenic (Tg) mice, peripheral T cells express the Vα2.3/Vβ8.2-Tg TCR, demonstrate vigorous proliferative responses to MBP in vitro, and can exhibit experimental autoimmune encephalomyelitis (EAE) within 5 days of pertussis toxin injection. We explored the effects of oral administration of MBP on the cellular trafficking of the MBP-specific TCR-Tg cells and the ability of oral MBP to protect Tg mice from EAE. Tg mice were fed MBP, OVA or vehicle and sacrificed at various times after feeding. An immediate and dramatic decrease in Vα2.3/Vβ8.2+-Tg cells was observed in the periphery within 1 h after feeding. By 3 days after feeding, the percentage of Tg cells increased to near control levels, but decreased again by 10 days. When MBP or vehicle-fed Tg mice were challenged for EAE at this point, disease was severe in the vehicle-fed mice and reduced in the MBP-fed mice over the 40-day observation period. In vitro studies revealed a biphasic pattern of MBP proliferative unresponsiveness and an induction of Th1 cytokines. Immunohistochemical staining showed that the number of Tg cells found in the intestinal lamina propria increased dramatically as the number of Tg cells in the periphery decreased. There was no apparent proliferation of Tg cells in the lamina propria, indicating that Tg cells trafficked there from the periphery. Taken together, these results suggest that T cell trafficking into the site of Ag deposition acts to protect the TCR-Tg mouse from EAE.
Carcinogen-Induced Inflammation and Immunosuppression Are Enhanced in Xeroderma Pigmentosum Group A Model Mice Associated with Hyperproduction of Prostaglandin E2
Authors: Miyauchi-Hashimoto Hiroko , Kuwamoto Kazue , Urade Yoshihiro , Tanaka Kiyoji , Horio Takeshi 
Published: April 2014

Abstract
Xeroderma pigmentosum group A (XPA) gene-deficient mice easily developed skin cancers by the application of topical chemical carcinogens as well as by UV irradiation. As certain chemical carcinogens have been shown to be immunosuppressive, we examined the inflammatory and immunosuppressive effects of dimethylbenz(a)anthracene (DMBA) on XPA mice. Compared with wild-type mice, XPA mice showed greater ear swelling and reduction of epidermal Langerhans cells after DMBA application. Topical application of DMBA impaired the induction of contact hypersensitivity, initiated either locally or at distant sites. These DMBA-induced local and systemic immunosuppressions were more greatly enhanced in XPA mice than in wild-type mice. DMBA application induced pronounced production of PGE2, IL-10, and TNF-α in the skin of XPA mice. Treatment with indomethacin, a potent inhibitor of PG biosynthesis, inhibited DMBA-induced inflammation and local immunosuppression. In XPA mice, increased serum IL-10 was detected after DMBA treatment. Excess production of PGE2, TNF-α, and IL-10 after DMBA application may be involved in the enhanced local and systemic immunosuppression in DMBA-treated XPA mice. Susceptibility to DMBA-induced skin tumors in XPA mice may be due to easy impairment of the immune system by DMBA in addition to a defect in the repair of DMBA-DNA adduct. Enhanced immunosuppression by chemical carcinogens as well as the mutagenicity of these mutagens might be associated with the high incidence of internal malignancies seen in XP patients. Moreover, these results supported the hypothesis that persistent DNA damage is a trigger for the production of immunoregulatory cytokines.
A Murine IL-4 Receptor Antagonist That Inhibits IL-4- and IL-13-Induced Responses Prevents Antigen-Induced Airway Eosinophilia and Airway Hyperresponsiveness
Authors: Tomkinson A. , Duez C. , Cieslewicz G. , Pratt J. C. , Joetham A. , Shanafelt M.-C. , Gundel R. , Gelfand E. W. 
Published: April 2014

Abstract
The closely related Th2 cytokines, IL-4 and IL-13, share many biological functions that are considered important in the development of allergic airway inflammation and airway hyperresponsiveness (AHR). The overlap of their functions results from the IL-4R α-chain forming an important functional signaling component of both the IL-4 and IL-13 receptors. Mutations in the C terminus region of the IL-4 protein produce IL-4 mutants that bind to the IL-4R α-chain with high affinity, but do not induce cellular responses. A murine IL-4 mutant (C118 deletion) protein (IL-4R antagonist) inhibited IL-4- and IL-13-induced STAT6 phosphorylation as well as IL-4- and IL-13-induced IgE production in vitro. Administration of murine IL-4R antagonist during allergen (OVA) challenge inhibited the development of allergic airway eosinophilia and AHR in mice previously sensitized with OVA. The inhibitory effect on airway eosinophilia and AHR was associated with reduced levels of IL-4, IL-5, and IL-13 in the bronchoalveolar lavage fluid as well as reduced serum levels of OVA-IgE. These observations demonstrate the therapeutic potential of IL-4 mutant protein receptor antagonists that inhibit both IL-4 and IL-13 in the treatment of allergic asthma.
Possible Involvement of EBV-Mediated α-Fodrin Cleavage for Organ-Specific Autoantigen in Sjogren’s Syndrome
Authors: Inoue Hiroko , Tsubota Kazuo , Ono Masafumi , Kizu Yasuhiro , Mizuno Fumio , Takada Kenzo , Yamada Koichi , Yanagi Kumiko , Hayashi Yoshio , Saito Ichiro 
Published: April 2014

Abstract
A cleavage product of α-fodrin may be an important organ-specific autoantigen in the pathogenesis of Sjogren’s syndrome (SS), but the mechanisms of α-fodrin cleavage remain unclear. Since EBV has been implicated in the pathogenesis of SS, we determined whether EBV activation could induce the SS-specific 120-kDa autoantigen α-fodrin. ZEBRA mRNA expression, a marker for activation of the lytic cycle of EBV, was found in the salivary gland tissues from SS patients, but not in those from control individuals. ZEBRA-expressing lymphoid cells were also found in the SS glands in double-stained immunohistochemistry. Furthermore, a significant link between production of Abs against 120-kDa α-fodrin and reactivated EBV Ag was found in sera from patients with SS, but not in those from control individuals. EBV-activated lymphoid cells showed specific α-fodrin cleavage to the expected 120-kDa fragments in vitro. Pretreatment with caspase inhibitors inhibited cleavage of α-fodrin. Thus, an increase in apoptotic protease activities induced by EBV reactivation may be involved in the progression of α-fodrin proteolysis in the development of SS.
SIN-1, a Nitric Oxide Donor, Ameliorates Experimental Allergic Encephalomyelitis in Lewis Rats in the Incipient Phase: The Importance of the Time Window
Authors: Xu Ling-Yun , Yang Jian-She , Link Hans , Xiao Bao-Guo 
Published: April 2014

AbstractNO is involved in the regulation of immune responses. The role of NO in the pathogenesis of experimental allergic encephalomyelitis (EAE) is controversial. In this study, 3-morpholinosydnonimine (SIN-1), an NO donor, was administered to Lewis rats on days 5–7 postimmunization, i.e., during the incipient phase of EAE. SIN-1 reduced clinical signs of EAE compared with those in PBS-treated control rats and was accompanied by reduced ED1+ macrophages and CD4+ T cell infiltration within the CNS. Blood mononuclear cells (MNC) obtained on day 14 postimmunization revealed that SIN-1 administration enhanced NO and IFN-γ production by blood MNC and suppressed Ag- and mitogen-induced proliferative responses. MHC class II, B7-1 and B7-2 were down-regulated in SIN-1-treated EAE rats. Simultaneously, frequencies of apoptotic cells among blood MNC were increased. In vivo, SIN-1 is likely to behave as an NO donor. Administration of SIN-1 induced NO production, but did not affect superoxide and peroxynitrite formation. Enhanced NO production during the priming phase of EAE thus promotes apoptosis, down-regulates disease-promoting immune reactivities, and ameliorates clinical EAE, mainly through SIN-1-derived NO, without depending on NO synthase.
Kinetics of TCR Use in Response to Repeated Epitope-Specific Immunization
Authors: Monsurrò Vladia , Nielsen Mai-Britt , Perez-Diez Ainhoa , Dudley Mark E. , Wang Ena , Rosenberg Steven A. , Marincola Francesco M. 
Published: April 2014

Abstract
Selection of T cell-directed immunization strategies is based extensively on discordant information derived from preclinical models. We characterized the kinetics of T cell selection in response to repeated antigenic challenge. By enumerating with epitope/HLA tetrameric complexes (tHLA) vaccine-elicited T cell precursor frequencies (Tc-pf) in melanoma patients exposed to the modified gp100 epitope gp100:209–217 (g209-2M) we observed in most patients that the Tc-pf increased with number of immunizations. One patient’s kinetics were further characterized. Dissociation kinetics of g209-2M/tHLA suggested enrichment of T cell effector populations expressing TCR with progressively higher affinity. Furthermore, vaccine-elicited T cells maintained the ability to express IFN-γ ex vivo and proliferate in vitro. Thus, repeated exposure to immunogenic peptides benefited immune competence. These results provide a rationale for immunization strategies.
Cognate T Cell Help Is Sufficient to Trigger Anti-Nuclear Autoantibodies in Naive Mice
Authors: Keech Catherine L. , Farris A. Darise , Beroukas Dimitra , Gordon Tom P. , McCluskey James 
Published: April 2014

AbstractThe mechanisms involved in the initiation of anti-nuclear autoantibodies are unknown. In this study, we show that one factor allowing anti-nuclear autoantibodies to develop is the incomplete nature of immune tolerance to many of these proteins. Immune responses in mice toward the ubiquitous nuclear autoantigen La/SS-B are much weaker than responses to the xenoantigen, human La (hLa; 74% identical). However, in transgenic (Tg) mice expressing hLa, the Ab response to this neo-autoantigen was reduced to a level resembling the weak autoimmune response to mouse La. Partial tolerance to endogenous La autoantigen was restricted to the T compartment because transfer of CD4+ T cells specific for one or more hLa determinants into mice bearing the hLa transgene was sufficient to elicit production of anti-hLa autoantibodies. Notably, only hLa- specific T cells from non-Tg mice, and not T cells from hLa Tg mice, induced autoantibody production in hLa Tg mice. These findings confirm partial Th tolerance to endogenous La and indicate the existence in normal animals of autoreactive B cells continuously presenting La nuclear Ag. Therefore, the B cell compartment is constitutively set to respond to particular nuclear autoantigens, implicating limiting Th responses as a critical checkpoint in the development of anti-nuclear autoantibodies in normal individuals.
Anti-CD3ε F(ab′)2 Prevents Graft-Versus-Host Disease by Selectively Depleting Donor T Cells Activated by Recipient Alloantigens
Authors: Yu Xue-Zhong , Bidwell Sasha J. , Martin Paul J. , Anasetti Claudio 
Published: April 2014

AbstractTransplantation tolerance is facilitated by activation-induced apoptosis of peripheral T cells triggered by specific Ag. Abs specific for the nonpolymorphic CD3 component of the TCR complex bind to APCs through Fc-FcR interactions, mimic MHC-peptide, and activate polyclonal T cells. In contrast, F(ab′)2 of anti-CD3ε Abs do not activate naive T cells but induce apoptosis of Ag-activated, cycling T cells. Here, we report that treatment with anti-CD3ε F(ab′)2 can selectively induce apoptosis of donor T cells that recognize a recipient alloantigen, thereby preventing graft-vs-host disease initiated by a TCR-transgenic T cell population. The selective elimination of Ag-activated T cells by non-FcR-binding anti-CD3ε Abs could serve as an ideal strategy to prevent graft-vs-host disease and allograft rejection or to treat autoimmune disorders.
Differential Regulation of Chemokine Production in Human Peritoneal Mesothelial Cells: IFN-γ Controls Neutrophil Migration Across the Mesothelium In Vitro and In Vivo
Authors: Robson Rachel L. , McLoughlin Rachel M. , Witowski Janusz , Loetscher Pius , Wilkinson Thomas S. , Jones Simon A. , Topley Nicholas 
Published: April 2014

AbstractLeukocyte recruitment into the infected peritoneal cavity consists of an early, predominant polymorphonuclear leukocyte (PMN) influx and subsequent, prolonged mononuclear cell migration phase. Although chemokine secretion by resident peritoneal cells plays a primary role in mediating this migration, the mechanisms involved in controlling the switch in phenotype of cell infiltrate remain unclear. The present study investigates a potential role for the Th1-type cytokine IFN-γ in the process of leukocyte recruitment into the peritoneal cavity. Stimulation of cultured human peritoneal mesothelial cells with IFN-γ (1–100 U/ml) alone or in combination with IL-1β (100 pg/ml) or TNF-α (1000 pg/ml) resulted in significant up-regulation of monocyte chemoattractant protein-1 and RANTES protein secretion. In contrast, IFN-γ inhibited basal and IL-1β-, and TNF-α-induced production of IL-8. The modulating effects of IFN-γ on chemokine production occurred at the level of gene expression, and the degree of regulation observed was dependent on the doses of IL-1β and TNF-α used. Analysis of the functional effects of IFN-γ on IL-1β-induced transmesothelial PMN migration with an in vitro human transmigration system and an in vivo murine model of peritoneal inflammation demonstrated that IFN-γ was able to down-regulate PMN migration induced by optimal doses of IL-1β. These effects were mediated in vivo via down-regulation of CXC chemokine synthesis. These findings suggest that IFN-γ may play a role in controlling the phenotype of infiltrating leukocyte during the course of an inflammatory response, in part via regulation of resident cell chemokine synthesis.
Cutting Edge: IFN-Inducible ELR− CXC Chemokines Display Defensin-Like Antimicrobial Activity
Authors: Cole Alexander M. , Ganz Tomas , Liese Amy M. , Burdick Marie D. , Liu Lide , Strieter Robert M. 
Published: April 2014

AbstractRecent reports highlighted the chemotactic activities of antimicrobial peptide defensins whose structure, charge, and size resemble chemokines. By assaying representative members of the four known families of chemokines we explored the obverse: whether some chemokines exert antimicrobial activity. In a radial diffusion assay, only recombinant monokine induced by IFN-γ (MIG/CXCL9), IFN-γ-inducible protein of 10 kDa (IP-10/CXCL10), and IFN-inducible T cell α chemoattractant (I-TAC/CXCL11), members of the IFN-γ-inducible tripeptide motif Glu-Leu-Arg (ELR)− CXC chemokines, were antimicrobial against Escherichia coli and Listeria monocytogenes. Similar to human defensins, antimicrobial activities of the chemokines were inhibited by 50 and 100 mM NaCl. The concentration of MIG/CXCL9 and IP-10/CXCL10 released from IFN-γ-stimulated PBMC in 24 h were, respectively, 35- and 28-fold higher than from unstimulated cells. Additionally, the amounts of chemokines released per monocyte suggest that, in tissues with mononuclear cell infiltration, IFN-γ-inducible chemokines may reach concentrations necessary for microbicidal activity. IFN-γ-inducible chemokines may directly inactivate microbes before attracting other host defense cells to the area of infection.