bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonmucosal Alphavirus Vaccination Stimulates a Mucosal Inductive Environment in the Peripheral Draining Lymph Node
Authors: Thompson Joseph M. , Nicholson Michael G. , Whitmore Alan C. , Zamora Melodie , West Ande , Iwasaki Akiko , Staats Herman F. , Johnston Robert E. 
Published: April 2014

Abstract
The strongest mucosal immune responses are induced following mucosal Ag delivery and processing in the mucosal lymphoid tissues, and much is known regarding the immunological parameters which regulate immune induction via this pathway. Recently, experimental systems have been identified in which mucosal immune responses are induced following nonmucosal Ag delivery. One such system, footpad delivery of Venezuelan equine encephalitis virus replicon particles (VRP), led to the local production of IgA Abs directed against both expressed and codelivered Ags at multiple mucosal surfaces in mice. In contrast to the mucosal delivery pathway, little is known regarding the lymphoid structures and immunological components that are responsible for mucosal immune induction following nonmucosal delivery. In this study, we have used footpad delivery of VRP to probe the constituents of this alternative pathway for mucosal immune induction. Following nonmucosal VRP delivery, J chain-containing, polymeric IgA Abs were detected in the peripheral draining lymph node (DLN), at a time before IgA detection at mucosal surfaces. Further analysis of the VRP DLN revealed up-regulated α4β7 integrin expression on DLN B cells, expression of mucosal addressin cell adhesion molecule 1 on the DLN high endothelia venules, and production of IL-6 and CC chemokines, all characteristics of mucosal lymphoid tissues. Taken together, these results implicate the peripheral DLN as an integral component of an alternative pathway for mucosal immune induction. A further understanding of the critical immunological and viral components of this pathway may significantly improve both our knowledge of viral-induced immunity and the efficacy of viral-based vaccines.
MyD88 Regulation of Fusarium Keratitis Is Dependent on TLR4 and IL-1R1 but Not TLR2
Authors: Tarabishy Ahmad B. , Aldabagh Bishr , Sun Yan , Imamura Yoshifumi , Mukherjee Pranab K. , Lass Jonathan H. , Ghannoum Mahmoud A. , Pearlman Eric 
Published: April 2014

Abstract
The fungal pathogens Fusarium solani and Fusarium oxysporum cause severe corneal disease in the United States and worldwide and were the causative organisms in a recent outbreak of contact lens-associated keratitis. To characterize innate immunity in Fusarium keratitis, we developed a murine model in which conidia are injected into the corneal stroma. Immunocompetent C57BL/6 mice rapidly developed severe corneal opacification associated with neutrophil infiltration and clearance of Fusarium hyphae. In contrast, neutrophil infiltration was delayed in MyD88−/− mice, resulting in uncontrolled growth of Fusarium hyphae in the corneal stroma and anterior chamber, and eventually resulting in corneal perforation. Corneal opacification scores in TLR2−/−, TLR4−/−, and TLR2/4−/− mice were similar to those of C57BL/6 mice; however, TLR4−/− and TLR2/4−/− mice had impaired antifungal responses. The phenotype of infected IL-1R1−/− mice was similar to that of MyD88−/− mice, with uncontrolled fungal growth resulting in corneal perforation. IL-1R1−/− mice also produced significantly less CXCL1/KC in the corneal stroma compared with C57BL/6 mice consistent with delayed neutrophil recruitment to the corneal stroma. Together, these findings indicate that IL-1R1 and MyD88 regulate CXC chemokine production and neutrophil recruitment to the cornea, and that TLR4 has an important role in controlling growth and replication of these pathogenic fungi.
Surfactant Protein A Binds to HIV and Inhibits Direct Infection of CD4+ Cells, but Enhances Dendritic Cell-Mediated Viral Transfer
Authors: Gaiha Gaurav D. , Dong Tao , Palaniyar Nades , Mitchell Daniel A. , Reid Kenneth B. M. , Clark Howard W. 
Published: April 2014

Abstract
The identification of surfactant protein A (SP-A) as an important innate immune factor of the lungs, amniotic fluid, and the vaginal tract suggests that it could play an important role during various stages of HIV disease progression and transmission. Therefore, we examined whether SP-A could bind to HIV and also had any effect on viral infectivity. Our data demonstrate that SP-A binds to HIV in a calcium-dependent manner that is inhibitable by mannose and EDTA. Affinity capture of the HIV viral lysate reveals that SP-A targets the envelope glycoprotein of HIV (gp120), which was confirmed by ELISA using recombinant gp120. Digestion of gp120 with endoglycosidase H abrogates the binding of SP-A, indicating that the high mannose structures on gp120 are the target of the collectin. Infectivity studies reveal that SP-A inhibits the infection of CD4+ T cells by two strains of HIV (BaL, IIIB) by &gt;80%. Competition assays with CD4 and mAbs F105 and b12 suggest that SP-A inhibits infectivity by occlusion of the CD4-binding site. Studies with dendritic cells (DCs) demonstrate that SP-A enhances the binding of gp120 to DCs, the uptake of viral particles, and the transfer of virus from DCs to CD4+ T cells by &gt;5-fold at a pH representative of the vaginal tract. Collectively, these results suggest that SP-A acts as a dual modulator of HIV infection by protecting CD4+ T cells from direct infection but enhancing the transfer of infection to CD4+ T cells mediated by DCs.
Terminal Deoxynucleotidyl Transferase Establishes and Broadens Antiviral CD8+ T Cell Immunodominance Hierarchies
Authors: Haeryfar S. M. Mansour , Hickman Heather D. , Irvine Kari R. , Tscharke David C. , Bennink Jack R. , Yewdell Jonathan W. 
Published: April 2014

Abstract
The action of TdT on mouse TCR genes accounts for ∼90% of T cell repertoire diversity. We report that in TdT−/− mice, total TCD8+ responses to influenza and vaccinia viruses are reduced by ∼30% relative to wild-type mice. We find that TCD8+ responses to three subdominant influenza virus determinants are reduced to background values in TdT−/− mice while responses to three immunodominant determinants undergo a major reshuffling. A similar reshuffling occurs in TCD8+ responses to immunodominant vaccinia virus determinants, and is clearly based on broad differences in TCR family usage and CDR3 length between wild-type and TdT−/− mice. These findings demonstrate that TdT plays a critical role in the magnitude and breadth of anti-viral TCD8+ responses toward individual determinants and suggests that germline TCR repertoire bias toward the most dominant determinants is a major factor in establishing immunodominance hierarchies.
Potent Anti-Inflammatory and Neuroprotective Effects of TGF-β1 Are Mediated through the Inhibition of ERK and p47phox-Ser345 Phosphorylation and Translocation in Microglia
Authors: Qian Li , Wei Sung-Jen , Zhang Dan , Hu Xiaoming , Xu Zongli , Wilson Belinda , El-Benna Jamel , Hong Jau-Shyong , Flood Patrick M. 
Published: April 2014

Abstract
TGF-β1 is one of the most potent endogenous immune modulators of inflammation. The molecular mechanism of its anti-inflammatory effect on the activation of the transcription factor NF-κB has been well-studied; however, the potential effects of TGF-β1 on other proinflammatory signaling pathways is less clear. In this study, using the well-established LPS and the 1-methyl-4-phenylpyridinium-mediated models of Parkinson’s disease, we demonstrate that TGF-β1 exerts significant neuroprotection in both models via its anti-inflammatory properties. The neuroprotective effects of TGF-β1 are mainly attributed to its ability to inhibit the production of reactive oxygen species from microglia during their activation or reactivation. Moreover, we demonstrate that TGF-β1 inhibited LPS-induced NADPH oxidase (PHOX) subunit p47phox translocation from the cytosol to the membrane in microglia within 10 min. Mechanistic studies show that TGF-β1 fails to protect dopaminergic neurons in cultures from PHOX knockout mice, and significantly reduced LPS-induced translocation of the PHOX cytosolic subunit p47phox to the cell membrane. In addition, LPS-induced ERK phosphorylation and subsequent Ser345 phosphorylation on p47phox were significantly inhibited by TGF-β1 pretreatment. Taken together, our results show that TGF-β1 exerted potent anti-inflammatory and neuroprotective properties, either through the prevention of the direct activation of microglia by LPS, or indirectly through the inhibition of reactive microgliosis elicited by 1-methyl-4-phenylpyridinium. The molecular mechanisms of TGF-β1-mediated anti-inflammatory properties is through the inhibition of PHOX activity by preventing the ERK-dependent phosphorylation of Ser345 on p47phox in microglia to reduce oxidase activities induced by LPS.
The Transcription Factor Nrf2 Is a Therapeutic Target against Brain Inflammation
Authors: Innamorato Nadia G. , Rojo Ana I. , García-Yagüe Ángel J. , Yamamoto Masayuki , de Ceballos María L. , Cuadrado Antonio 
Published: April 2014

Abstract
Because chronic neuroinflammation is a hallmark of neurodegenerative diseases and compromises neuron viability, it is imperative to discover pharmacologic targets to modulate the activation of immune brain cells, the microglia. In this study, we identify the transcription factor Nrf2, guardian of redox homeostasis, as such target in a model of LPS-induced inflammation in mouse hippocampus. Nrf2 knockout mice were hypersensitive to the neuroinflammation induced by LPS, as determined by an increase in F4/80 mRNA and protein, indicative of an increase in microglial cells, and in the inflammation markers inducible NO synthase, IL-6, and TNF-α, compared with the hippocampi of wild-type littermates. The aliphatic isothiocyanate sulforaphane elicited an Nrf2-mediated antioxidant response in the BV2 microglial cell line, determined by flow cytometry of cells incubated with the redox sensitive probe dihydrodichlorofluorescein diacetate, and by the Nrf2-dependent induction of the phase II antioxidant enzyme heme oxygenase-1. Animals treated with sulforaphane displayed a 2–3-fold increase in heme oxygenase-1, a reduced abundance of microglial cells in the hippocampus and an attenuated production of inflammation markers (inducible NO synthase, IL-6, and TNF-α) in response to LPS. Considering that release of reactive oxygen species is a property of activated microglia, we propose a model in which late induction of Nrf2 intervenes in the down-regulation of microglia. This study opens the possibility of targeting Nrf2 in brain as a means to modulate neuroinflammation.
Transcriptome Analysis Reveals Human Cytomegalovirus Reprograms Monocyte Differentiation toward an M1 Macrophage
Authors: Chan Gary , Bivins-Smith Elizabeth R. , Smith M. Shane , Smith Patrick M. , Yurochko Andrew D. 
Published: April 2014

Abstract
Monocytes are primary targets for human CMV (HCMV) infection and are proposed to be responsible for hematogenous dissemination of the virus. Monocytes acquire different functional traits during polarization to the classical proinflammatory M1 macrophage or the alternative antiinflammatory M2 macrophage. We hypothesized that HCMV induced a proinflammatory M1 macrophage following infection to promote viral dissemination because, biologically, a proinflammatory state provides the tools to drive infected monocytes from the blood into the tissue. To test this hypothesis of monocyte conversion from a normal quiescent phenotype to an inflammatory phenotype, we used Affymetrix Microarray to acquire a transcriptional profile of infected monocytes at a time point our data emphasized is a key temporal regulatory point following infection. We found that HCMV significantly up-regulated 583 (5.2%) of the total genes and down-regulated 621 (5.5%) of the total genes ≥1.5-fold at 4 h postinfection. Further ontology analysis revealed that genes implicated in classical M1 macrophage activation were stimulated by HCMV infection. We found that 65% of genes strictly associated with M1 polarization were up-regulated, while only 4% of genes solely associated with M2 polarization were up-regulated. Analysis of the monocyte chemokinome at the transcriptional level showed that 44% of M1 and 33% of M2 macrophage chemokines were up-regulated. Proteomic analysis using chemokine Ab arrays confirmed the secretion of these chemotactic proteins from HCMV-infected monocytes. Overall, the results identify that the HCMV-infected monocyte transcriptome displayed a unique M1/M2 polarization signature that was skewed toward the classical M1 activation phenotype.
Fetal Exposure to High-Avidity TCR Ligand Enhances Expansion of Peripheral T Regulatory Cells
Authors: Yu Ping , Haymaker Cara L. , Divekar Rohit D. , Ellis Jason S. , Hardaway John , Jain Renu , Tartar Danielle M. , Hoeman Christine M. , Cascio Jason A. , Ostermeier Austin , Zaghouani Habib 
Published: April 2014

Abstract
Lately, it has become clear that regulatory T cells (Tregs) play a major role in the maintenance of peripheral tolerance and control of autoimmunity. Despite these critical functions, the process underlying the development of Tregs remains largely undefined. Herein, altered peptide ligand (APL) variants derived from the proteolipid protein-1 (PLP1) epitope were expressed on immunoglobulins (Igs) and the resulting Ig-APLs were used to deliver the APLs from mother to fetus through the maternal placenta to influence thymic T cell selection. This delivery system was then adapted to the SJL/J mouse, a strain that expresses only the DM20 form of PLP, which lacks the dominant PLP1 epitope in the thymus during fetal and neonatal development. This model, which restores thymic T cell selection for PLP1, was then used to determine whether affinity plays a role in the development of Tregs. The findings show that fetal exposure to low-affinity peptide ligand was unable to drive development of Tregs while variants with higher affinity to the TCR resulted in significant seeding of the periphery with mature, naive Tregs. Thus, contrary to pathogenic T cells, Tregs require avid TCR-ligand interaction to undergo thymic development and maturation.
The Anergic State in Sarcoidosis Is Associated with Diminished Dendritic Cell Function
Authors: Mathew Sneha , Bauer Kristy L. , Fischoeder Arne , Bhardwaj Nina , Oliver Stephen J. 
Published: April 2014

Abstract
Sarcoidosis is a chronic inflammatory disease of unknown cause, characterized by granuloma formation similar to tuberculosis, but without clear evidence of a microbial infection. Because sarcoidosis is linked with clinical anergy and other evidence of diminished cellular immunity, we hypothesized that decreased skin delayed-type hypersensitivity (DTH) responses to recall Ags in affected individuals would be associated with decreased function of their blood dendritic cells (DCs). Our study involved ex vivo isolation, phenotyping, and functional testing of myeloid DCs (mDCs), plasmacytoid DCs, and T lymphocytes from blood of normal healthy volunteers and sarcoidosis subjects with active, untreated pulmonary disease. We found mDC function in the allogeneic MLR directly corresponded to the magnitude of skin DTH reactions to recall Ags in both sarcoidosis subjects and normal volunteers. However, both of these outcomes were significantly decreased in the sarcoidosis group. Diminished mDC function occurred despite up-regulated costimulatory and maturation markers. Clinical relevance is suggested by the inverse relationship between both mDC allogeneic responses and skin DTH responses with clinical disease severity as measured by chest radiograms. Because granulomas form when cellular immunity fails to clear antigenic stimuli, attenuated mDC function in sarcoidosis may contribute to susceptibility and persistence of the chronic inflammation characteristic of this disease.
Cutting Edge: Experimentally Induced Immune Activation in Natural Hosts of Simian Immunodeficiency Virus Induces Significant Increases in Viral Replication and CD4+ T Cell Depletion
Authors: Pandrea Ivona , Gaufin Thaidra , Brenchley Jason M. , Gautam Rajeev , Monjure Christopher , Gautam Aarti , Coleman Clint , Lackner Andrew A. , Ribeiro Ruy M. , Douek Daniel C. , Apetrei Cristian 
Published: April 2014

Abstract
Chronically SIVagm-infected African green monkeys (AGMs) have a remarkably stable nonpathogenic disease course, with levels of immune activation in chronic SIVagm infection similar to those observed in uninfected monkeys and with stable viral loads for long periods of time. In vivo administration of LPS or an IL-2/diphtheria toxin fusion protein (Ontak) to chronically SIVagm-infected AGMs triggered increases in immune activation and subsequently of viral replication and depletion of intestinal CD4+ T cells. Our study indicates that circulating microbial products can increase viral replication by inducing immune activation and increasing the number of viral target cells, thus demonstrating that immune activation and T cell proliferation are key factors in AIDS pathogenesis.
Cutting Edge: Eosinophils Do Not Contribute to Respiratory Syncytial Virus Vaccine-Enhanced Disease
Authors: Castilow Elaine M. , Legge Kevin L. , Varga Steven M. 
Published: April 2014

Abstract
Respiratory syncytial virus (RSV) infection of BALB/c mice previously immunized with a recombinant vaccinia virus (vacv) expressing the attachment (G) protein of RSV (vacvG) results in pulmonary eosinophilia, which mimics the response of formalin-inactivated RSV-vaccinated children, as well as increased weight loss, clinical illness, and enhanced pause (Penh). We show that RSV infection of eosinophil-deficient mice previously immunized with vacvG results in the development of increased weight loss, clinical illness, and Penh similar to that in wild-type controls. These measures of RSV vaccine-enhanced disease are dependent upon STAT4. Interestingly, neither IL-12 nor IL-23, the two most common STAT4-activating cytokines, proved necessary for the development of disease. We demonstrate that IFN-γ, which is produced following STAT4 activation, contributes to clinical illness and increased Penh, but not weight loss. Our results have important implications for future RSV vaccine design, suggesting that enhancing a Th1 response may exacerbate disease.
Cutting Edge: FimH Adhesin of Type 1 Fimbriae Is a Novel TLR4 Ligand
Authors: Mossman Karen L. , Mian M. Firoz , Lauzon Nicole M. , Gyles Carlton L. , Lichty Brian , Mackenzie Randy , Gill Navkiran , Ashkar Ali A. 
Published: April 2014

Abstract
Several TLR ligands of bacterial origin induce innate immune responses. Although FimH, the adhesin portion of type 1 fimbria, plays an important role in the pathogenicity of some Gram-negative bacteria, its ability to stimulate the innate immune system via TLR signaling remains unclear. In this study we report that FimH induces potent innate responses in a MyD88-dependent fashion. The FimH-induced innate activity was restricted to cells expressing TLR4. In addition, FimH was able to bind directly to TLR4. More importantly, cells unresponsive to LPS were responsive to FimH and the presence or absence of MD-2 and CD14 had no effect on FimH activity. Our data suggest that TLR4 is a functional receptor for the adhesin portion of bacterial type 1 fimbria.
Cutting Edge: Programmed Death-1/Programmed Death Ligand 1 Interaction Regulates the Induction and Maintenance of Invariant NKT Cell Anergy
Authors: Chang Woo-Sung , Kim Ji-Yeon , Kim Yeon-Jeong , Kim Yun-Sun , Lee Jung-Mi , Azuma Miyuki , Yagita Hideo , Kang Chang-Yuil 
Published: April 2014

Abstract
Invariant NKT (iNKT) cells are a distinct subset of T lymphocytes that recognize glycolipid Ags. Upon TCR stimulation, iNKT cells promptly secrete a wide range of cytokines and therefore have been investigated as a target for immunotherapy. However, after primary activation, iNKT cells become hyporesponsive toward their ligand (anergy). The further mechanism behind iNKT cell anergy is poorly understood. We found that a low level of programmed death-1 (PD-1) was constitutively expressed on iNKT cells and that PD-1 expression was increased after stimulation and lasted at least 2 mo. Moreover, not only did blocking of the PD-1/PD ligand 1 (PD-L1) pathway prevent the induction of anergy in iNKT cells, but anergic iNKT cells also recovered responsiveness and these “rescued” cells efficiently mediated antitumor immunity. Our findings suggest that the PD-1/PD-L1 interaction is essential for the induction and maintenance of iNKT cell anergy.
Reversible Blockade of Thymic Output: An Inherent Part of TLR Ligand-Mediated Immune Response
Authors: Démoulins Thomas , Abdallah Ali , Kettaf Nadia , Baron Marie-Laurence , Gerarduzzi Casimiro , Gauchat Dominique , Gratton Sophie , Sékaly Rafick-Pierre 
Published: April 2014

Abstract
TLRs constitute a first set of sensors that detect viral nucleic acids including dsRNA which triggers TLR3. We report the early, direct, and detrimental effect of polyinosine-polycytidilic acid treatment on T cell development. Inhibition of thymopoiesis was targeted to several thymocyte subpopulations. First, both a blockade of the double negative (DN)1-DN2 transition and a severe down-regulation of DN3-DN4 thymocyte proliferation were observed. In addition, an important decrease in the absolute numbers of double-positive thymocytes, concomitant with an increase in frequencies of apoptotic cells in this population were shown. This inhibition of thymopoiesis resulted in a reduced thymic output, as evidenced by a drop of the absolute numbers of naive T cells and TCR excision circles levels. The decrease in thymic cellularity and defects in thymic development were severely reduced, but not completely abolished in IFN-α/βR−/− mice, showing a direct contribution of type I IFNs, known to be massively up-regulated in viral infections, to the inhibition of T cell development. Strikingly, the TCR repertoire in treated mice was biased toward shorter CDR3 lengths as a result of a decreased expression of TdT and Rag2. However, thymic integrity remained intact since thymopoiesis was restored both quantitatively and qualitatively 14 days after the cessation of polyinosine-polycytidilic acid treatment. These results demonstrate a novel immunomodulatory role for virally encoded TLR ligands and RNA sensors; they further illustrate the diversity of mechanisms that viruses use to interfere with the development of a pathogen-specific immune responses.
Adaptable TCR Avidity Thresholds for Negative Selection
Authors: Stojakovic Milica , Salazar-Fontana Laura I. , Tatari-Calderone Zohreh , Badovinac Vladimir P. , Santori Fabio R. , Kovalovsky Damian , Sant'Angelo Derek , Harty John T. , Vukmanovic Stanislav 
Published: April 2014

Abstract
Central tolerance plays a significant role in preventing autoimmune diseases by eliminating T cells with high and intermediate avidity for self. To determine the manner of setting the threshold for deletion, we created a unique transgenic mouse strain with a diverse T cell population and globally increased TCR avidity for self-peptide/MHC complexes. Despite the adaptations aimed at reducing T cell reactivity (reduced TCR levels and increased levels of TCR signaling inhibitor CD5), transgenic mice displayed more severe experimental allergic encephalomyelitis and lupus. The numbers and activity of natural (CD4+CD25+) regulatory T cells were not altered. These findings demonstrate that the threshold for deletion is adaptable, allowing survival of T cells with higher avidity when TCR avidity is globally increased.