bluuebunny/crossref_metadata_2025_split huggingface dataset:
Src Tyrosine Kinases Mediate Activations of NF-κB and Integrin Signal during Lipopolysaccharide-Induced Acute Lung Injury
Authors: Lee Hui S. , Moon Changsuk , Lee Hye W. , Park Eun-Mi , Cho Min-Sun , Kang Jihee L. 
Published: April 2014

Abstract
Src tyrosine kinases (TKs) are signaling proteins involved in cell signaling pathways toward cytoskeletal, membrane and nuclear targets. In the present study, using a selective Src TK inhibitor, PP1, we investigated the roles of Src TKs in the key pulmonary responses, NF-κB activation, and integrin signaling during acute lung injury in BALB/C mice intratracheally treated with LPS. LPS resulted in c-Src phosphorylation in lung tissue and the phospho-c-Src was predominantly localized in recruited neutrophils and alveolar macrophages. PP1 inhibited LPS-induced increases in total protein content in bronchoalveolar lavage fluid, neutrophil recruitment, and increases in the production or activity of TNF-α and matrix metalloproteinase-9. PP1 also blocked LPS-induced NF-κB activation, and phosphorylation and degradation of IκB-α. The inhibition of NF-κB activation by PP1 correlated with a depression of LPS-induced integrin signaling, which included increases in the phosphorylations of integrin β3, and of the focal adhesion kinase (FAK) family members, FAK and Pyk2, in lung tissue, and reductions in the fibrinogen-binding activity of alveolar macrophages. Moreover, treatment with anti-αv, anti-β3, or Arg-Gly-Asp-Ser (RGDS), inhibited LPS-induced NF-κB activation. Taken together, our findings suggest that Src TKs play a critical role in LPS-induced activations of NF-κB and integrin (αvβ3) signaling during acute lung injury. Therefore, Src TK inhibition may provide a potential means of ameliorating inflammatory cascade-associated lung injury.
Involvement of Vitronectin in Lipopolysaccaride-Induced Acute Lung Injury
Authors: Tsuruta Yuko , Park Young-Jun , Siegal Gene P. , Liu Gang , Abraham Edward 
Published: April 2014

Abstract
Vitronectin is present in large concentrations in serum and participates in regulation of humoral responses, including coagulation, fibrinolysis, and complement activation. Because alterations in coagulation and fibrinolysis are common in acute lung injury, we examined the role of vitronectin in LPS-induced pulmonary inflammation. Vitronectin concentrations were significantly increased in the lungs after LPS administration. Neutrophil numbers and proinflammatory cytokine levels, including IL-1β, MIP-2, KC, and IL-6, were significantly reduced in bronchoalveolar lavage fluid from vitronectin-deficient (vitronectin−/−) mice, as compared with vitronectin+/+ mice, after LPS exposure. Similarly, LPS induced increases in lung edema, myeloperoxidase-concentrations, and pulmonary proinflammatory cytokine concentrations were significantly lower in vitronectin−/− mice. Vitronectin−/− neutrophils demonstrated decreased KC-induced chemotaxis as compared with neutrophils from vitronectin+/+ mice, and incubation of vitronectin+/+ neutrophils with vitronectin was associated with increased chemotaxis. Vitronectin−/− neutrophils consistently produced more TNF-α, MIP-2, and IL-1β after LPS exposure than did vitronectin+/+ neutrophils and also showed greater degradation of IκB-α and increased LPS-induced nuclear accumulation of NF-κB compared with vitronectin+/+ neutrophils. These findings provide a novel vitronectin-dependent mechanism contributing to the development of acute lung injury.
IFN-γ Produced by Human Papilloma Virus-18 E6-Specific CD4+ T Cells Predicts the Clinical Outcome after Surgery in Patients with High-Grade Cervical Lesions
Authors: Seresini Samantha , Origoni Massimo , Lillo Flavia , Caputo Luigi , Paganoni Anna Maria , Vantini Simone , Longhi Renato , Taccagni Gianluca , Ferrari Augusto , Doglioni Claudio , Secchi Piercesare , Protti Maria Pia 
Published: April 2014

Abstract
Cervical neoplastic lesions are associated with infection by high-risk human papilloma viruses (HPVs). HPV-16 and HPV-18 are the most common genotypes. It has been proposed that development of HPV-16-positive cervical lesions is associated with impaired CD4+ T cell immunity against early Ags. The aim of the study was to evaluate whether this impairment also applies to HPV-18. We investigated the presence and the quality of anti-HPV-18 E6 CD4+ T cell responses in the blood of 37 consecutive patients with high-grade cervical lesions, 25 normal donors, and 20 cord bloods. The immune infiltrate in the cervical lesions was also evaluated. The characteristics of the responses were correlated to the clinical outcome. We found that one or more HPV-18 E6 peptides, containing naturally processed epitopes, were able to induce a response in 40–50% of the patients, depending on the effector function tested. Importantly, these percentages rose to 80–100% when HPV-18-positive patients were considered. HPV-18 E6-specific CD4+ T cells produced mixed Th1/Th2 responses and statistical analysis of the cytokines produced revealed that the amount of IFN-γ released could predict infection persistence and/or disease relapse after surgery. Finally, we found that a higher number of infiltrating CD4+ and T-bet+ T cells in the lesions correlated with a favorable clinical outcome. Our results strongly suggest a relevant role for CD4+ T cells in the control of the HPV-18 compared with HPV-16 infections in patients with high-grade cervical lesions and identify an immunologic parameter potentially useful for patients’ stratification.
Invertebrate Immune Systems–Specific, Quasi-Specific, or Nonspecific?
Authors: Rowley Andrew F. , Powell Adam 
Published: April 2014

Abstract
Until recently, it was widely accepted that invertebrates fail to show a high degree of specificity and memory in their immune strategies. Recent reports have challenged this view such that our understanding of the capabilities of the invertebrate immune systems needs to be reassessed. This account critically reviews the available evidence that suggests the existence of a high degree of memory and specificity in some invertebrates and seeks mechanistic explanations of such observations. It is postulated that elevated levels of phagocytosis may be a partial explanation for this phenomenon.
CTLA-4 · FasL Induces Early Apoptosis of Activated T Cells by Interfering with Anti-Apoptotic Signals
Authors: Orbach Ariel , Rachmilewitz Jacob , Parnas Miram , Huang Jui-Han , Tykocinski Mark L. , Dranitzki-Elhalel Michael 
Published: April 2014

Abstract
The fusion protein CTLA-4 · FasL, a paradigmatic “trans signal converter protein”, can attach to APC surfaces and in effect convert B7-activating costimulator signals into inhibitory Fas receptor-generated signals. The present study investigates CTLA-4 · FasL’s mechanism of action. A combination of p27kip and proliferating cell nuclear Ag Western blot and propidium iodide flow cytometric analysis showed no CTLA-4 · FasL effect on cell cycle entry and progression, pointing away from the kind of classical anergy associated with CTLA-4 · Ig. Significantly, CTLA-4 · FasL elicited apoptosis (as detected by annexin-V/propidium iodide costaining) as early as 24 h after T cell activation, suggesting that some coordinate signaling might be capacitating the Fas receptor. Significantly, CTLA-4 · FasL, but not CTLA-4 · Ig, anti-Fas mAb, or the two in combination, abrogated the usual increase in expression of the anti-apototic protein, cFLIP. Furthermore, activation of caspases 8 and 3 were not affected by CTLA-4 · FasL. These findings suggest a model for CTLA-4 · FasL action wherein there is coordinate triggering of a death receptor and suppression of a proapoptotic protein.
Ex Vivo Expansion of CD4+CD25+FoxP3+ T Regulatory Cells Based on Synergy between IL-2 and 4-1BB Signaling
Authors: Elpek Kutlu G. , Yolcu Esma S. , Franke Deanna D. H. , Lacelle Chantale , Schabowsky Rich-Henry , Shirwan Haval 
Published: April 2014

Abstract
Naturally occurring CD4+CD25+FoxP3+ T regulatory (Treg) cells require three distinct signals transduced via TCR, CD28, and IL-2R for their development and maintenance. These requirements served as the basis for several recently developed ex vivo expansion protocols that relied on the use of solid support-bound Abs to CD3 and CD28 in the presence of high dose IL-2. We report in this study that Treg cells up-regulate the expression of inducible costimulatory receptor 4-1BB in response to IL-2, and stimulation using this receptor via a novel form of 4-1BB ligand (4-1BBL) fused to a modified form of core streptavidin (SA-4-1BBL) was effective in expanding these cells up to 110-fold within 3 wk. Expanded cells up-regulated CD25, 4-1BB, and membranous TGF-β, suppressed T cell proliferation, and prevented the rejection of allogeneic islets upon adoptive transfer into graft recipients. Importantly, SA-4-1BBL rendered CD4+CD25− T effector cells refractive to suppression by Treg cells. This dual function of signaling via 4-1BB, vis-à-vis Treg cell expansion and licensing T effector cells resistant to Treg cell suppression, as well as the up-regulation of 4-1BB by IL-2 may serve as important regulatory mechanisms for immune homeostasis following antigenic challenge. Stimulation using a soluble form of SA-4-1BBL represents a novel approach to expand Treg cells with potential therapeutic applications in autoimmunity and transplantation.
Ikaros Enforces the Costimulatory Requirement for IL2 Gene Expression and Is Required for Anergy Induction in CD4+ T Lymphocytes
Authors: Thomas Rajan M. , Chunder Neelanjana , Chen Chunxia , Umetsu Sarah E. , Winandy Susan , Wells Andrew D. 
Published: April 2014

Abstract
T cell activation results in dynamic remodeling of the chromatin at the IL2 promoter and induction of IL2 gene transcription. These processes are each dependent upon CD28 costimulation, but the molecular basis for this requirement is not clear. The IL2 promoter contains consensus-binding elements for Ikaros, a lymphocyte-specific zinc-finger DNA-binding protein that can regulate gene expression by recruiting chromatin-remodeling complexes. We find that native Ikaros in CD4+ T cells exhibits sequence-specific binding to these elements in vitro, and interacts with the endogenous IL2 promoter in vivo, in a manner dependent upon its DNA-binding domain. This binding has important consequences on the regulation of the IL2 gene, because CD4+ T cells with reduced Ikaros DNA-binding activity no longer require signals from the TCR or CD28 for histone acetylation at the endogenous IL2 promoter, and no longer require CD28 costimulation for expression of the IL2 gene. Furthermore, CD4+ T cells with reduced Ikaros activity are resistant to clonal anergy induced by TCR ligation in the absence of either CD28 or IL-2R signals. These results establish Ikaros as a transcriptional repressor of the IL2 gene that functions through modulation of chromatin structure and has an obligate role in the induction of anergy.
NKp30 Ligation Induces Rapid Activation of the Canonical NF-κB Pathway in NK Cells
Authors: Pandey Rahul , DeStephan Christine M. , Madge Lisa A. , May Michael J. , Orange Jordan S. 
Published: April 2014

Abstract
Studies of patients with congenital immunodeficiency due to mutation of the NF-κB essential modulator (NEMO) gene have demonstrated that NEMO integrity is required for NK cell cytotoxicity. Thus, we have studied the physiology of NF-κB activation in NK cells during the cytolytic program. In resting ex vivo human NK cells or cell lines, IκB was degraded after 10 min exposure to PMA and ionomycin, or TNF and was maximally degraded by 30 min. Ligation of several NK cell activation receptors including NKp30 induced a similar response and was blocked by pretreatment with the proteosome inhibitor MG132. There was no short-term effect on p100 processing, the signature of noncanonical NF-κB activation. NK cell IκB degradation corresponded to increases in nuclear NF-κB as detected by EMSA. Supershift of stimulated NK cells and fluorescence microscopy of individual NK cells in cytolytic conjugates demonstrated that the p65/p50 heterodimer was the primary NF-κB used. NF-κB function was evaluated in NK92 cells transduced with a κB GFP reporter, and their conjugation with K562 cells or ligation of NKp30 ligation resulted in rapid GFP accumulation. The latter was prevented by the Syk inhibitor piceatannol. Thus, NK cell activation signaling specifically induces transcriptional activation and synthesis of new NF-κB dependent proteins during the initiation of cytotoxicity.
Differential Development of Murine Dendritic Cells by GM-CSF versus Flt3 Ligand Has Implications for Inflammation and Trafficking
Authors: Xu Yuekang , Zhan Yifan , Lew Andrew M. , Naik Shalin H. , Kershaw Michael H. 
Published: April 2014

Abstract
To gain ample numbers of dendritic cells (DCs) for investigation, or for immunotherapy, the culture of DC precursors from bone marrow in either GM-CSF and IL-4 (GM/IL4-DCs) or Flt3L (FL-DCs) has often been used. Despite their common use, the relationship of these culture-derived DCs to those in vivo, and their relative potential for use in immunotherapy, needs further elucidation. In this study we found that in contrast to FL-DCs, highly purified GM/IL4-DCs were larger and more granular, surface Mac-3+, and were comprised of two populations (CD24lowCD11bhigh and CD24highCD11blow). Functionally, although comparable in T cell activation, GM/IL4-DCs produced more inflammatory mediators including TNF-α, IL-10, CCL-2, and NO than FL-DCs upon TLR ligation. However, FL-DCs migrated more efficiently to draining lymph nodes after s.c. injection and produced a different profile of cytokines to GM/IL4-DCs. Developmentally, unlike GM/IL4-DCs, FL-DCs cannot be differentiated from CD11bhighLy6ChighLy6G− monocytes. Collectively, these data suggest that the GM/IL4-DCs are the equivalents of the TNF-α and inducible NO synthase producing DCs in vivo that emerge after inflammation whereas FL-DCs better represent the steady-state resident DCs. The differences between GM/IL4-DCs and FL-DCs have serious implications for DC-based immunotherapeutic strategies.
Soluble CD14 Discriminates Slight Structural Differences between Lipid As That Lead to Distinct Host Cell Activation
Authors: Asai Yasuyuki , Makimura Yutaka , Kawabata Atsushi , Ogawa Tomohiko 
Published: April 2014

Abstract
Soluble CD14 (sCD14) in serum is known to sensitize host cells to LPS. In the present study, the contributions of sCD14 and LPS-binding protein to a lipid A moiety from LPS preparations of periodontopathogenic Fusobacterium nucleatum sp. nucleatum were compared with that of Escherichia coli-type synthetic lipid A (compound 506). F. nucleatum lipid A was identified to be a hexa-acylated fatty acid composed of tetradecanoate (C14) and hexadecanoate (C16), similar to dodecanoate (C12) and C14 in compound 506. The two lipid A specimens exhibited nearly the same reactivity in Limulus amoebocyte lysate assays, though F. nucleatum lipid A showed a weaker lethal toxicity. Both lipid A specimens showed nearly the same activities toward host cells in the absence of FBS, though compound 506 exhibited much stronger activity in the presence of FBS, sCD14, or sCD14 together with LPS-binding protein. Furthermore, native PAGE/Western immunoblot assays demonstrated that F. nucleatum lipid A had a weaker binding to sCD14 as compared with compound 506. These results suggest that sCD14 is able to discriminate the slight structural differences between these lipid As, which causes their distinct host cell activation activities.
Differential Requirements by CD4+ and CD8+ T Cells for Soluble and Membrane TNF in Control of Francisella tularensis Live Vaccine Strain Intramacrophage Growth
Authors: Cowley Siobhán C. , Sedgwick Jonathon D. , Elkins Karen L. 
Published: April 2014

Abstract
During primary infection with intracellular bacteria, the membrane-associated form of TNF provides some TNF functions, but the relative contributions during memory responses are not well-characterized. In this study, we determined the role of T cell-derived secreted and membrane-bound TNF (memTNF) during adaptive immunity to Francisella tularensis live vaccine strain (LVS). Although transgenic mice expressing only the memTNF were more susceptible to primary LVS infection than wild-type (WT) mice, LVS-immune WT and memTNF mice both survived maximal lethal secondary Francisella challenge. Generation of CD44high memory T cells and clearance of bacteria were similar, although more IFN-γ and IL-12(p40) were produced by memTNF mice. To examine T cell function, we used an in vitro tissue coculture system that measures control of LVS intramacrophage growth by LVS-immune WT and memTNF-T cells. LVS-immune CD4+ and CD8+ T cells isolated from WT and memTNF mice exhibited comparable control of LVS growth in either normal or TNF-α knockout macrophages. Although the magnitude of CD4+ T cell-induced macrophage NO production clearly depended on TNF, control of LVS growth by both CD4+ and CD8+ T cells did not correlate with levels of nitrite. Importantly, intramacrophage LVS growth control by CD8+ T cells, but not CD4+ T cells, was almost entirely dependent on T cell-expressed TNF, and required stimulation through macrophage TNFRs. Collectively, these data demonstrate that T cell-expressed memTNF is necessary and sufficient for memory T cell responses to this intracellular pathogen, and is particularly important for intramacrophage control of bacterial growth by CD8+ T cells.
Secretory IgA Mediates Bacterial Translocation to Dendritic Cells in Mouse Peyer’s Patches with Restriction to Mucosal Compartment
Authors: Kadaoui Khalil A. , Corthésy Blaise 
Published: April 2014

Abstract
In addition to fulfilling its function of immune exclusion at mucosal surfaces, secretory IgA (SIgA) Ab exhibits the striking feature to adhere selectively to M cells in the mouse and human intestinal Peyer’s patches (PPs). Subsequent uptake drives the SIgA Ab to dendritic cells (DCs), which become partially activated. Using freshly isolated mouse DCs, we found that the interaction with SIgA was tissue and DC subtype dependent. Only DCs isolated from PPs and mesenteric lymph nodes interacted with the Ab. CD11c+CD11b+ DCs internalized SIgA, while CD11c+CD19+ DCs only bound SIgA on their surface, and no interaction occurred with CD11c+CD8α+ DCs. We next examined whether SIgA could deliver a sizeable cargo to PP DCs in vivo by administering SIgA-Shigella flexneri immune complexes into a mouse ligated intestinal loop containing a PP. We found that such immune complexes entered the PPs and were internalized by subepithelial dome PP DCs, in contrast to S. flexneri alone that did not penetrate the intestinal epithelium in mice. Dissemination of intraepithelial S. flexneri delivered as immune complexes was limited to PPs and mesenteric lymph nodes. We propose that preexisting SIgA Abs associated with microbes contribute to mucosal defense by eliciting responses that prevent overreaction while maintaining productive immunity.
Identification of Signaling Pathways in Macrophage Exposed to Porphyromonas gingivalis or to Its Purified Cell Wall Components
Authors: Zhou Qingde , Amar Salomon 
Published: April 2014

Abstract
Porphyromonas gingivalis (P. gingivalis) can trigger an inflammatory condition leading to the destruction of periodontal tissues. However P. gingivalis LPS and its fimbriae (FimA) play different roles compared with the live bacteria in the context of intracellular molecule induction and cytokine secretion. To elucidate whether this difference results from different signaling pathways in host immune response to P. gingivalis, its LPS, or its FimA, we examined gene expression profile of human macrophages exposed to P. gingivalis, its LPS, or its FimA. A comparison of gene expression resulted in the identification of three distinct groups of expressed genes. Furthermore, computer-assisted promoter analysis of a subset of each group of differentially regulated genes revealed four putative transcriptional regulation models that associate with transcription factors NFκB, IRF7, and KLF4. Using gene knockout mice and siRNA to silence mouse genes, we showed that both TLR2 and TLR7 are essential for the induction of NFκB-containing genes and NFκB-IFN-sensitive response element (ISRE) cocontaining genes by either P. gingivalis or its purified components. The gene induction via either TLR2 or TLR7 is dependent on both MyD88 and p38 MAPK. However, the unique induction of IFN-β by P. gingivalis LPS requires TLR7 and IFNαβR cosignaling, and the induction of ISRE-containing gene is dependent on the activation of IFN-β autocrine loop. Taken together, these data demonstrate that P. gingivalis and its components induce NFκB-containing genes through either TLR2- or TLR7-MyD88-p38 MAPK pathway, while P. gingivalis LPS uniquely induces ISRE-containing genes, which requires IFNαβR signaling involving IRF7, KLF4, and pY701 STAT1.
Activation of p38 MAPK by Reactive Oxygen Species Is Essential in a Rat Model of Stress-Induced Gastric Mucosal Injury
Authors: Jia Yi-Tao , Wei Wei , Ma Bing , Xu Yu , Liu Wen-Jun , Wang Yu , Lv Kai-Yang , Tang Hong-Tai , Wei Duo , Xia Zhao-Fan 
Published: April 2014

Abstract
Stress ulceration is a common complication in critically ill patients and can result in significant upper gastrointestinal bleeding associated with a high morbidity and mortality. At present, little is known of the molecular mechanisms underlying the incidence of this type of gastric damage. In the present study, we investigated the temporal activation of the redox-sensitive p38 signaling transduction cascade and its roles in a well-defined experimental model of cold immobilization stress-induced gastric ulceration. Exposure of Sprague-Dawley rats to 6 h of cold immobilization stress led to a rapid activation of p38 in the gastric mucosa at as early as 15 min after stress, and this activation was maximal after 1.5 h of stress and still persisted until the end of stress. Selectively blocking p38 by pretreatment with SB 239063, a potent and selective p38 inhibitor, suppressed the stress-promoted TNF-α, IL-1β, and CINC-1 production and then prevented the subsequent neutrophil infiltration, gastric mucosal epithelial necrosis and apoptosis, and the ulcerative lesions formation. Prior administration of the free radical scavengers, tempol and N-acetyl-l-cysteine, abolished the stress induction of p38 activation and the resulting mucosal inflammation and gastric injury. These results demonstrate that reactive oxygen species-mediated p38 activation plays an essential role in the pathogenesis of stress-induced gastric inflammatory damage in the rat model of cold immobilization stress. Our findings suggested that inhibition of p38 activation might be a potential strategy for the prophylaxis and treatment of stress ulceration.
Inhibition of CINC-1 Decreases Right Ventricular Damage Caused by Experimental Pulmonary Embolism in Rats
Authors: Zagorski John , Gellar Michael A. , Obraztsova Maria , Kline Jeffrey A. , Watts John A. 
Published: April 2014

Abstract
Right ventricular (RV) dysfunction is a strong risk factor for poor clinical outcome following pulmonary embolism (PE), the third most prevalent cardiovascular disease. Previous studies in our laboratory demonstrated that RV failure during PE is mediated, in part, by neutrophil-dependant cardiac inflammation. In this study we use DNA microarray analysis of gene expression to demonstrate that PE results in increased expression of the CXC chemokines CINC-1 and CINC-2 between 6 and 18 h after the start of PE in a rat model of PE. Neutrophils accumulate in RV tissue by 18 h, and this inflammation is associated with decreased right heart function. Treatment of rats with Abs to CINC-1 significantly suppressed neutrophil accumulation in RVs during PE (52% reduction in tissue myeloperoxidase) and ameliorated RV failure. In addition, plasma concentration of cardiac troponin I, an established diagnostic marker for cardiac damage, was reduced by 90%. These results suggest that selective anti-inflammatory therapies targeted at neutrophil chemoattractants will reduce cardiac inflammation and reduce RV damage in the setting of PE.