bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Cytokine IL-1β Activates IFN Response Factor 3 in Human Fetal Astrocytes in Culture
Authors: Rivieccio Mark A. , John Gareth R. , Song Xianyuan , Suh Hyeon-Sook , Zhao Yongmei , Lee Sunhee C. , Brosnan Celia F. 
Published: April 2014

AbstractThe cytokine IL-1β is a major activator of primary human fetal astrocytes in culture, leading to the production of a wide range of cytokines and chemokines important in the host defense against pathogens. IL-1β, like TLR4, signals via the MyD88/IL-1βR-associated kinase-1 pathway linked to activation of NF-κB and AP-1. Recent studies have shown that TLR4 also signals independently of MyD88, resulting in the activation of IFN regulatory factor 3 (IRF3), a transcription factor required for the production of primary antiviral response genes such as IFN-β. Using a functional genomics approach, we observed that IL-1β induced in astrocytes a group of genes considered to be IFN-stimulated genes (ISG), suggesting that IL-1β may also signal via IRF3 in these cells. We now show, using real-time PCR, that in astrocytes IL-1β induces the expression of IFN-β, IRF7, CXCL10/IFN-γ-inducible protein-10, and CCL5/RANTES. Chemokine expression was confirmed by ELISA. We also show that IL-1β induces phosphorylation and nuclear translocation of IRF3 and delayed phosphorylation of STAT1. The dependency of IFN-β, IRF7, and CXCL10/IFN-γ-inducible protein-10 gene expression on IRF3 was confirmed using a dominant negative IRF3-expressing adenovirus. The robust induction by IL-1β of additional ISG noted on the microarrays, such as STAT1, 2′5′-oligoadenylate synthetase 2, and ISG15, also supports an active signaling role for IL-1β via this pathway in human fetal astrocytes. These data are the first to show that IL-1β, in addition to TLRs, can stimulate IRF3, implicating this cytokine as an activator of genes involved in innate antiviral responses in astrocytes.
Modulation of Phagocytosis of Apoptotic Neutrophils by Supernatant from Dexamethasone-Treated Macrophages and Annexin-Derived Peptide Ac2–26
Authors: Maderna Paola , Yona Simon , Perretti Mauro , Godson Catherine 
Published: April 2014

AbstractPhagocytic clearance of apoptotic leukocytes plays an important role in the resolution of inflammation. The glucocorticoid-inducible protein annexin 1 and annexin 1-derived peptides show potent anti-inflammatory responses in acute and chronic inflammation. In this study, we report that the annexin 1-derived peptide (Ac2–26) significantly stimulates nonphlogistic phagocytosis of apoptotic polymorphonuclear leukocytes (PMNs) by human monocyte-derived macrophages (Mφ). Peptide Ac2–26-stimulated phagocytosis is accompanied by rearrangement of the Mφ actin cytoskeleton. To investigate the potential role of endogenous annexin on clearance of apoptotic cells, Mφ were cultured for 5 days in the presence of dexamethasone. Supernatants collected from dexamethasone-treated Mφ significantly enhanced the ability of naive Mφ to engulf apoptotic PMNs. This effect was blocked by an annexin blocking Ab, by immunodepletion of the supernatants, and by the formyl peptide receptor/lipoxin receptor antagonist Boc1. In addition, we show that bone marrow-derived Mφ from annexin 1-null mice present a 40% decreased phagocytosis of apoptotic PMNs compared with cells taken from littermate controls. In conclusion, these results emphasize the pivotal role of annexin 1 as mediator for clearance of apoptotic cells and expand its potential therapeutic role in controlling inflammatory diseases.
Alloreactive T Cell Responses and Acute Rejection of Single Class II MHC-Disparate Heart Allografts Are under Strict Regulation by CD4+CD25+ T Cells
Authors: Schenk Soren , Kish Danielle D. , He Chunshui , El-Sawy Tarek , Chiffoleau Eise , Chen Chuangqui , Wu Zihao , Sandner Sigrid , Gorbachev Anton V. , Fukamachi Kiyotaka , Heeger Peter S. , Sayegh Mohamed H. , Turka Laurence A. , Fairchild Robert L. 
Published: April 2014

AbstractSkin but not vascularized cardiac allografts from B6.H-2bm12 mice are acutely rejected by C57BL/6 recipients in response to the single class II MHC disparity. The underlying mechanisms preventing acute rejection of B6.H-2bm12 heart allografts by C57BL/6 recipients were investigated. B6.H-2bm12 heart allografts induced low levels of alloreactive effector T cell priming in C57BL/6 recipients, and this priming was accompanied by low-level cellular infiltration into the allograft that quickly resolved. Recipients with long-term-surviving heart allografts were unable to reject B6.H-2bm12 skin allografts, suggesting potential down-regulatory mechanisms induced by the cardiac allografts. Depletion of CD25+ cells from C57BL/6 recipients resulted in 15-fold increases in alloreactive T cell priming and in acute rejection of B6.H-2bm12 heart grafts. Similarly, reconstitution of B6.Rag−/− recipients with wild-type C57BL/6 splenocytes resulted in acute rejection of B6.H-2bm12 heart grafts only if CD25+ cells were depleted. These results indicate that acute rejection of single class II MHC-disparate B6.H-2bm12 heart allografts by C57BL/6 recipients is inhibited by the emergence of CD25+ regulatory cells that restrict the clonal expansion of alloreactive T cells.
Immunization with Lentiviral Vector-Transduced Dendritic Cells Induces Strong and Long-Lasting T Cell Responses and Therapeutic Immunity
Authors: He Yukai , Zhang Jiying , Mi Zhibao , Robbins Paul , Falo Louis D. 
Published: April 2014

AbstractDendritic cell (DC) therapies are currently being evaluated for the treatment of cancer. The majority of ongoing clinical trials use DCs loaded with defined antigenic peptides or proteins, or tumor-derived products, such as lysates or apoptotic cells, as sources of Ag. Although several theoretical considerations suggest that DCs expressing transgenic protein Ags may be more effective immunogens than protein-loaded cells, methods for efficiently transfecting DCs are only now being developed. In this study we directly compare the immunogenicity of peptide/protein-pulsed DCs with lentiviral vector-transduced DCs, and their comparative efficacy in tumor immunotherapy. Maturing, bone marrow-derived DCs can be efficiently transduced with lentiviral vectors, and transduction does not affect DC maturation, plasticity, or Ag presentation function. Transduced DCs efficiently process and present both MHC class I- and II-restricted epitopes from the expressed transgenic Ag OVA. Compared with peptide- or protein-pulsed DCs, lentiviral vector-transduced DCs elicit stronger and longer-lasting T cell responses in vivo, as measured by both in vivo killing assays and intracellular production of IFN-γ by Ag-specific T cells. In the B16-OVA tumor therapy model, the growth of established tumors was significantly inhibited by a single immunization using lentiviral vector-transduced DCs, resulting in significantly longer survival of immunized animals. These results suggest that compared with Ag-pulsed DCs, vaccination with lentiviral vector-transduced DCs may achieve more potent antitumor immunity. These data support the further development of lentiviral vectors to transduce DCs with genes encoding Ags or immunomodulatory adjuvants to generate and control systemic immune responses.
Reducing the Stimulation of CD8+ T Cells during Infection with Intracellular Bacteria Promotes Differentiation Primarily into a Central (CD62LhighCD44high) Subset
Authors: van Faassen Henk , Saldanha Marsha , Gilbertson Deanna , Dudani Renu , Krishnan Lakshmi , Sad Subash 
Published: April 2014

Abstract
During infection with lymphocytic choriomeningitis virus, CD8+ T cells differentiate rapidly into effectors (CD62LlowCD44high) that differentiate further into the central memory phenotype (CD62LhighCD44high) gradually. To evaluate whether this CD8+ T cell differentiation program operates in all infection models, we evaluated CD8+ T cell differentiation during infection of mice with recombinant intracellular bacteria, Listeria monocytogenes (LM) and Mycobacterium bovis (BCG), expressing OVA. We report that CD8+ T cells primed during infection with the attenuated pathogen BCG-OVA differentiated primarily into the central subset that correlated to reduced attrition of the primed cells subsequently. CD8+ T cells induced by LM-OVA also differentiated into central phenotype cells first, but the cells rapidly converted into effectors in contrast to BCG-OVA. Memory CD8+ T cells induced by both LM-OVA as well as BCG-OVA were functional in that they produced cytokines and proliferated extensively in response to antigenic stimulation after adoptive transfer. During LM-OVA infection, if CD8+ T cells were guided to compete for access to APCs, then they received reduced stimulation that was associated with increased differentiation into the central subset and reduced attrition subsequently. Similar effect was observed when CD8+ T cells encountered APCs selectively during the waning phase of LM-OVA infection. Taken together, our results indicate that the potency of the pathogen can influence the differentiation and fate of CD8+ T cells enormously, and the extent of attrition of primed CD8+ T cells correlates inversely to the early differentiation of CD8+ T cells primarily into the central CD8+ T cell subset.
Priming in the Presence of IL-10 Results in Direct Enhancement of CD8+ T Cell Primary Responses and Inhibition of Secondary Responses
Authors: Kang Silvia S. , Allen Paul M. 
Published: April 2014

AbstractAlthough IL-10 acts as an inhibitory cytokine for APC and CD4+ T cell function, its effects on CD8+ T cells are unclear. Additionally, little is known about whether initial priming in the presence of IL-10 can have long-lasting effects and influence subsequent CD8+ T cell responses that occur in the absence of the cytokine. In the present study, we clarified the role of IL-10 during primary responses and examined whether exposure to IL-10 during initial priming of CD8+ T cells impacted secondary responses. To determine the effect of IL-10 on Ag-specific T cell responses, peptide-pulsed IL-10R2−/− splenic dendritic cells were used to prime T cells from OT-I CD8+ TCR transgenic mice. During the primary response, the presence of IL-10 resulted in enhancement of CD8+ T cell numbers without detectable alterations in the kinetics or percentage of cells that underwent proliferation. A modest increase in survival, not attributable to Bcl-2 or Bcl-xL, was also observed with IL-10 treatment. Other parameters of CD8+ T cell function, including IL-2, IFN-γ, TNF-α, and granzyme production, were unaltered. In contrast, initial exposure to IL-10 during the primary response resulted in decreased OT-I expansion during secondary stimulation. This was accompanied by lowered IL-2 levels and reduced percentages of proliferating BrdU+ cells and OT-I cells that were CD25high. IFN-γ, TNF-α, and granzyme production were unaltered. These data suggest that initial exposure of CD8+ T cells to IL-10 may be temporarily stimulatory; however, programming of the cells may be altered, resulting in diminished overall responses.
Saturated and Polyunsaturated Fatty Acids Reciprocally Modulate Dendritic Cell Functions Mediated through TLR4
Authors: Weatherill Amy R. , Lee Joo Y. , Zhao Ling , Lemay Danielle G. , Youn Hyung S. , Hwang Daniel H. 
Published: April 2014

Abstract
TLRs provide critical signals to induce innate immune responses in APCs such as dendritic cells (DCs) that in turn link to adaptive immune responses. Results from our previous studies demonstrated that saturated fatty acids activate TLRs, whereas n-3 polyunsaturated fatty acids inhibit agonist-induced TLR activation. These results raise a significant question as to whether fatty acids differentially modulate immune responses mediated through TLR activation. The results presented in this study demonstrate that the saturated fatty acid, lauric acid, up-regulates the expression of costimulatory molecules (CD40, CD80, and CD86), MHC class II, and cytokines (IL-12p70 and IL-6) in bone marrow-derived DCs. The dominant negative mutant of TLR4 or its downstream signaling components inhibits lauric acid-induced expression of a CD86 promoter-reporter gene. In contrast, an n-3 polyunsaturated fatty acid, docosahexaenoic acid, inhibits TLR4 agonist (LPS)-induced up-regulation of the costimulatory molecules, MHC class II, and cytokine production. Similarly, DCs treated with lauric acid show increased T cell activation capacity, whereas docosahexaenoic acid inhibits T cell activation induced by LPS-treated DCs. Together, our results demonstrate that the reciprocal modulation of both innate and adaptive immune responses by saturated fatty acid and n-3 polyunsaturated fatty acid is mediated at least in part through TLRs. These results imply that TLRs are involved in sterile inflammation and immune responses induced by nonmicrobial endogenous molecules. These results shed new light in understanding how types of dietary fatty acids differentially modulate immune responses that could alter the risk of many chronic diseases.
A Large Number of T Lymphocytes Recognize Moloney-Murine Leukemia Virus-Induced Antigens, but a Few Mediate Long-Lasting Tumor Immunosurveillance
Authors: Facchinetti Antonella , Santa Silvia Dalla , Mezzalira Silvio , Rosato Antonio , Biasi Giovanni 
Published: April 2014

Abstract
The CD8+ T cell response to Moloney-murine leukemia virus (M-MuLV)-induced Ags is almost entirely dominated by the exclusive expansion of lymphocytes that use preferential TCRVβ chain rearrangements. In mice lacking T cells expressing these TCRVβ, we demonstrate that alternative TCRVβ can substitute for the lack of the dominant TCRVβ in the H-2-restricted M-MuLV Ag recognition. We show that, at least for the H-2b-restricted response, the shift of TCR usage is not related to a variation of the immunodominant M-MuLV epitope recognition. After virus immunization, all the potentially M-MuLV-reactive lymphocytes are primed, but only the deletion of dominant Vβ rescues the alternative Vβ response. The mechanism of clonal T cell “immunodomination” that guides the preferential Vβ expansion is likely the result of a proliferative advantage of T cells expressing dominant Vβ, due to differences in TCR affinity and/or cosignal requirements. In this regard, a CD8 involvement is strictly required for the virus-specific cytotoxic activity of CTL expressing alternative, but not dominant, Vβ gene rearrangements. The ability of T cells expressing alternative TCRVβ rearrangements to mediate tumor protection was evaluated by a challenge with M-MuLV tumor cells. Although T cells expressing alternative Vβ chains were activated and expanded, they were not able to control tumor growth in a long-lasting manner due to their incapacity of conversion and accumulation in the T central memory pool.
Membrane IgE Binds and Activates FcεRI in an Antigen-Independent Manner
Authors: Vangelista Luca , Soprana Elisa , Cesco-Gaspere Michela , Mandiola Paola , Di Lullo Giulia , Fucci Rita N. , Codazzi Franca , Palini Alessio , Paganelli Giovanni , Burrone Oscar R. , Siccardi Antonio G. 
Published: April 2014

Abstract
Interaction of secretory IgE with FcεRI is the prerequisite for allergen-driven cellular responses, fundamental events in immediate and chronic allergic manifestations. Previous studies reported the binding of soluble FcεRIα to membrane IgE exposed on B cells. In this study, the functional interaction between human membrane IgE and human FcεRI is presented. Four different IgE versions were expressed in mouse B cell lines, namely: a truncation at the Cε2-Cε3 junction of membrane IgE isoform long, membrane IgE isoform long (without Igα/Igβ BCR accessory proteins), and both εBCRs (containing membrane IgE isoforms short and long). All membrane IgE versions activated a rat basophilic leukemia cell line transfected with human FcεRI, as detected by measuring the release of both preformed and newly synthesized mediators. The interaction led also to Ca2+ responses in the basophil cell line, while membrane IgE-FcεRI complexes were detected by immunoprecipitation. FcεRI activation by membrane IgE occurs in an Ag-independent manner. Noteworthily, human peripheral blood basophils and monocytes also were activated upon contact with cells bearing membrane IgE. In humans, the presence of FcεRI in several cellular entities suggests a possible membrane IgE-FcεRI-driven cell-cell dialogue, with likely implications for IgE homeostasis in physiology and pathology.
TLR2 Signaling Is Critical for Mycoplasma pneumoniae-Induced Airway Mucin Expression
Authors: Chu Hong Wei , Jeyaseelan Samithamby , Rino John G. , Voelker Dennis R. , Wexler Rachel B. , Campbell Krista , Harbeck Ronald J. , Martin Richard J. 
Published: April 2014

Abstract
Excessive airway mucin production contributes to airway obstruction in lung diseases such as asthma and chronic obstructive pulmonary disease. Respiratory infections, such as atypical bacterium Mycoplasma pneumoniae (Mp), have been proposed to worsen asthma and chronic obstructive pulmonary disease in part through increasing mucin. However, the molecular mechanisms involved in infection-induced airway mucin overexpression remain to be determined. TLRs have been recently shown to be a critical component in host innate immune response to infections. TLR2 signaling has been proposed to be involved in inflammatory cell activation by mycoplasma-derived lipoproteins. In this study, we show that TLR2 signaling is critical in Mp-induced airway mucin expression in mice and human lung epithelial cells. Respiratory Mp infection in BALB/c mice activated TLR2 signaling and increased airway mucin. A TLR2-neutralizing Ab significantly reduced mucin expression in Mp-infected BALB/c mice. Furthermore, Mp-induced airway mucin was abolished in TLR2 gene-deficient C57BL/6 mice. Additionally, Mp was shown to increase human lung A549 epithelial cell mucin expression, which was inhibited by the overexpression of a human TLR2 dominant-negative mutant. These results clearly demonstrate that respiratory Mp infection increases airway mucin expression, which is dependent on the activation of TLR2 signaling.
A CD8+ T Cell Heptaepitope Minigene Vaccine Induces Protective Immunity againstChlamydia pneumoniae
Authors: Pinchuk Irina , Starcher Barry C. , Livingston Brian , Tvninnereim Amy , Wu Shiping , Appella Ettore , Sidney John , Sette Alessandro , Wizel Benjamin 
Published: April 2014

AbstractAn intact T cell compartment and IFN-γ signaling are required for protective immunity against Chlamydia. In the mouse model of Chlamydia pneumoniae (Cpn) infection, this immunity is critically dependent on CD8+ T cells. Recently we reported that Cpn-infected mice generate an MHC class I-restricted CD8+ Tc1 response against various Cpn Ags, and that CD8+ CTL to multiple epitopes inhibit Cpn growth in vitro. Here, we engineered a DNA minigene encoding seven H-2b-restricted Cpn CTL epitopes, the universal pan-DR epitope Th epitope, and an endoplasmic reticulum-translocating signal sequence. Immunization of C57BL/6 mice with this construct primed IFN-γ-producing CD8+ CTL against all seven CTL epitopes. CD8+ T cell lines generated to minigene-encoded CTL epitopes secreted IFN-γ and TNF-α and exhibited CTL activity upon recognition of Cpn-infected macrophages. Following intranasal challenge with Cpn, a 3.6 log reduction in mean lung bacterial numbers compared with control animals was obtained. Using a 20-fold increase in the Cpn challenging dose, minigene-vaccinated mice had a 60-fold reduction in lung bacterial loads, compared with controls. Immunization and challenge studies with β2-microglobulin−/− mice indicated that the reduction of lung Cpn burdens was mediated by the MHC class I-dependent CD8+ T cells to minigene-included Cpn CTL epitopes, rather than by pan-DR epitope-specific CD4+ T cells. This constitutes the first demonstration of significant protection achieved by immunization with a CD8+ T cell epitope-based DNA construct in a bacterial system and provides the basis for the optimal design of multicomponent anti-Cpn vaccines for humans.
Endogenous Attenuation of Allergic Lung Inflammation by Syndecan-1
Authors: Xu Jie , Park Pyong Woo , Kheradmand Farrah , Corry David B. 
Published: April 2014

Abstract
The airway plays a vital role in allergic lung diseases by responding to inhaled allergens and initiating allergic inflammation. Various proinflammatory functions of the airway epithelium have been identified, but, equally important, anti-inflammatory mechanisms must also exist. We show in this study that syndecan-1, the major heparan sulfate proteoglycan of epithelial cells, attenuates allergic lung inflammation. Our results show that syndecan-1-null mice instilled with allergens exhibit exaggerated airway hyperresponsiveness, glycoprotein hypersecretion, eosinophilia, and lung IL-4 responses. However, administration of purified syndecan-1 ectodomains, but not ectodomain core proteins devoid of heparan sulfate, significantly inhibits these inflammatory responses. Furthermore, syndecan-1 ectodomains are shed into the airway when wild-type mice are intranasally instilled with several biochemically distinct inducers of allergic lung inflammation. Our results also show that syndecan-1 ectodomains bind to the CC chemokines (CCL7, CCL11, and CCL17) implicated in allergic diseases, inhibit CC chemokine-mediated T cell migration, and suppress allergen-induced accumulation of Th2 cells in the lung through their heparan sulfate chains. Together, these findings uncover an endogenous anti-inflammatory mechanism of the airway epithelium where syndecan-1 ectodomains attenuate allergic lung inflammation via suppression of CC chemokine-mediated Th2 cell recruitment to the lung.
Inhibition of Mammalian Target of Rapamycin Potentiates Thrombin-Induced Intercellular Adhesion Molecule-1 Expression by Accelerating and Stabilizing NF-κB Activation in Endothelial Cells
Authors: Minhajuddin Mohd , Fazal Fabeha , Bijli Kaiser M. , Amin Md. Ruhul , Rahman Arshad 
Published: April 2014

Abstract
We addressed the regulatory function of mammalian target of rapamycin (mTOR) in the mechanism of thrombin-induced ICAM-1 gene expression in endothelial cells. Pretreatment of HUVECs with rapamycin, an inhibitor of mTOR, augmented thrombin-induced ICAM-1 expression. Inhibition of mTOR by this approach promoted whereas over-expression of mTOR inhibited thrombin-induced transcriptional activity of NF-κB, an essential regulator of ICAM-1 transcription. Analysis of the NF-κB signaling pathway revealed that inhibition of mTOR potentiated IκB kinase activation resulting in a rapid and persistent phosphorylation of IκBα on Ser32 and Ser36, a requirement for IκBα degradation. Consistent with these data, we observed a more efficient and stable nuclear localization of RelA/p65 and, subsequently, the DNA binding activity of NF-κB by thrombin following mTOR inhibition. These data define a novel role of mTOR in down-regulating thrombin-induced ICAM-1 expression in endothelial cells by controlling a delayed and transient activation of NF-κB.
Space, Selection, and Surveillance: Setting Boundaries with BLyS
Authors: Miller Juli P. , Stadanlick Jason E. , Cancro Michael P. 
Published: April 2014

AbstractThe BLyS family of ligands and receptors governs B cell homeostasis by controlling survival, differentiation, and lifespan. This family consists of multiple receptors and ligands, allowing independent regulation of different B cell subsets by varying the combination and levels of receptors expressed. Multiple downstream signaling pathways are implicated in these activities, reflecting this receptor complexity as well as cross-talk with other B cell signaling systems. BLyS levels are associated with multiple forms of humoral autoimmunity and can modulate tolerogenic elimination at the transitional checkpoint. BLyS responsiveness thus balances peripheral selection against cell numbers, providing an elastic system that varies selective stringency based on homeostatic demands.