bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eosinophil Major Basic Protein Stimulates Neutrophil Superoxide Production by a Class IA Phosphoinositide 3-Kinase and Protein Kinase C-ζ-Dependent Pathway
Authors: Shenoy Neeta G. , Gleich Gerald J. , Thomas Larry L. 
Published: April 2014

Abstract
Eosinophil major basic protein (MBP) is an effective stimulus for neutrophil superoxide (O2−) production, degranulation, and IL-8 production. In this study we evaluated the participation of phosphoinositide 3-kinase (PI3K) and PI3K-associated signaling events in neutrophil activation by MBP. Inhibition of PI3K activity blocked MBP-stimulated O2− production, but not degranulation or IL-8 production. Measurement of Akt phosphorylation at Ser473 and Thr308 confirmed that MBP stimulated PI3K activity and also demonstrated indirectly activation of phosphoinositide-dependent kinase-1 by MBP. Genistein and the Src kinase family inhibitor, 4-amino-5-(4-methyphenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine, inhibited MBP-stimulated phosphorylation of Akt. 4-Amino-5-(4-methyphenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine also inhibited MBP-stimulated O2− production. MBP stimulated phosphorylation and translocation of the p85 subunit of class IA PI3K, but not translocation of the p110γ subunit of class IB PI3K, to the neutrophil membrane. Inhibition of protein kinase Cζ (PKCζ) inhibited MBP-stimulated O2− production. Measurement of phosphorylated PKCζ (Thr410) and PKCδ (Thr505) confirmed that PKCζ, but not PKCδ, is activated in MBP-stimulated neutrophils. The time courses for phosphorylation and translocation of the p85 subunit of class IA PI3K, activation of Akt, and activation of PKCζ were similar. Moreover, inhibition of PI3K activity inhibited MBP-induced activation of PKCζ. We conclude that MBP stimulates a Src kinase-dependent activation of class IA PI3K and, in turn, activation of PKCζ in neutrophils, which contributes to the activation of NADPH oxidase and the resultant O2− production in response to MBP stimulation.
Inhibition of Cytokine Gene Transcription by the Human Recombinant Histamine-Releasing Factor in Human T Lymphocytes
Authors: Vonakis Becky M. , Sora Rebecca , Langdon Jacqueline M. , Casolaro Vincenzo , MacDonald Susan M. 
Published: April 2014

Abstract
Human recombinant histamine-releasing factor (HrHRF) preincubation enhances the secretion of histamine, IL-4, and IL-13 from FcεRI-stimulated human basophils. In GM-CSF-primed human eosinophils, HrHRF increases IL-8 production. Our recent experiments were designed to evaluate the effects of HrHRF on human T cell cytokine production. Purified T cells were preincubated with GST-tagged HrHRF, followed by stimulation with PMA and A23187 overnight. A partial inhibition of IL-2 and IL-13 production (30 and 75%, respectively) was detected compared with that in cells treated with PMA/A23187 alone. However, the production of IFN-γ was similar in PMA/A23187 stimulated cells with or without HrHRF. The inhibition of cytokine protein production was dose dependent and specific to the HrHRF portion of GST-HrHRF. The inhibition was not due to endotoxin, since preincubation with polymyxin B and HrHRF gave similar results to that with HrHRF alone. The same pattern and specificity of cytokine regulation were replicated in the Jurkat T cell line as for primary T cells. The PMA/A23187-stimulated activity of a proximal promoter IL-13, IL-4, or IL-2 luciferase construct transfected into Jurkat cells was partially inhibited (60, 32, or 70%, respectively) upon GST-HrHRF preincubation, suggesting that HrHRF functions to inhibit cytokine production in Jurkat cells by preventing gene transcription. The inhibition of IL-2 promoter activation was specific to the HrHRF portion of GST-HrHRF. We conclude that HrHRF, in addition to functioning as a histamine-releasing factor, can differentially modulate the secretion of cytokines from human basophils, eosinophils, T cells, and murine B cells, suggesting that it may induce a complex array of responses at sites of allergic inflammation.
p21-Activated Kinase 2 in Neutrophils Can Be Regulated by Phosphorylation at Multiple Sites and by a Variety of Protein Phosphatases
Authors: Zhan Qian , Ge Qingyuan , Ohira Taisuke , Van Dyke Thomas , Badwey John A. 
Published: April 2014

Abstract
The p21-activated kinase(Pak) 2 undergoes rapid autophosphorylation/activation in neutrophils stimulated with a variety of chemoattractants (e.g., fMLP). Phosphorylation within the activation loop (Thr402) and inhibitory domain (Ser141) is known to increase the activity of Pak in vitro, whereas phosphorylation within the Nck (Ser20) and Pak-interacting guanine nucleotide exchange factor (Ser192 and Ser197) binding sites blocks the interactions of Pak 2 with these proteins. A panel of phosphospecific Abs was used to investigate the phosphorylation of Pak 2 in neutrophils at these sites. Pak 2 underwent rapid (≤15 s) phosphorylation at Ser20, Ser192/197, and Thr402 in neutrophils stimulated with fMLP. Phosphorylation at Ser192/197 and Thr402 were highly transient events, whereas that at Ser20 was more persistent. In contrast, Pak 2 was constitutively phosphorylated at Ser141 in unstimulated neutrophils and phosphorylation at this site was less sensitive to cell stimulation than at other residues. Studies with selective inhibitors suggested that a variety of phosphatases might be involved in the rapid dephosphorylation of Pak 2 at Thr402 in stimulated neutrophils. This was consistent with biochemical studies which showed that the activation loop of GST-Pak 3, which is homologous to that in Pak 2, was a substrate for protein phosphatase 1, 2A, and a Mg2+/Mn2+-dependent phosphatase(s) which exhibited properties different from those of the conventional isoforms of protein phosphatase 2C. The data indicate that Pak 2 undergoes a complex pattern of phosphorylation in neutrophils and that dephosphorylation at certain sites may involve multiple protein phosphatases that exhibit distinct modes of regulation.
Involvement of Dectin-2 in Ultraviolet Radiation-Induced Tolerance
Authors: Aragane Yoshinori , Maeda Akira , Schwarz Agatha , Tezuka Tadashi , Ariizumi Kiyoshi , Schwarz Thomas 
Published: April 2014

Abstract
Hapten sensitization through UV-exposed skin induces hapten-specific tolerance which can be adoptively transferred by injecting T cells into naive recipients. The exact phenotype of the regulatory T cells responsible for inhibiting the immune response and their mode of action remain largely unclear. Dectin-2 is a C-type lectin receptor expressed on APCs. It was postulated that dectin-2 interacts with its putative ligands on T cells and that the interaction may deliver costimulatory signals in naive T cells. Using a soluble fusion protein of dectin-2 (sDec2) which should inhibit this interaction, we studied the effect on contact hypersensitivity (CHS) and its modulation by UV radiation. Injection of sDec2 affected neither the induction nor the elicitation phase of CHS. In contrast, UV-induced inhibition of the CHS induction was prevented upon injection of sDec2. In addition, hapten-specific tolerance did not develop. Even more importantly, injection of sDec2 into tolerized mice rendered the recipients susceptible to the specific hapten, indicating that sDec2 can break established tolerance. FACS analysis of spleen and lymph node cells revealed a significantly increased portion of sDec2-binding T cells in UV-tolerized mice. Furthermore, transfer of UV-mediated suppression was lost upon depletion of the sDec2-positive T cells. Taken together, these data indicate that dectin-2 and its yet unidentified ligand may play a crucial role in the mediation of UV-induced immunosuppression. Moreover, sDec2-reactive T cells appear to represent the regulatory T cells responsible for mediating UV-induced tolerance.
Activation of Mast Cells Is Essential for Development of House Dust Mite Dermatophagoides farinae-Induced Allergic Airway Inflammation in Mice
Authors: Yu Chun-Keung , Chen Chih-Long 
Published: April 2014

Abstract
In this study, we demonstrate that Dermatophagoides farinae (Der f), a major source of airborne allergens, but not OVA, could rapidly activate mast cells in mice. This was indicated by an elevation of serum mouse mast cell protease 1, a mast cell-specific proteinase, as early as 30 min after intratracheal challenge. Administration of sodium cromoglycate (40 mg/kg, i.p., 1 h before Der f instillation), a mast cell stabilizer, not only suppressed acute mouse mast cell protease 1 production but also attenuated the allergic airway inflammation provoked by repetitive Der f challenge in mice (five times at 1-wk interval). Der f induced the expression of mRNA for TNF-α, IL-1β, IL-4, IL-6, IL-9, and IL-13 in mastocytoma P815 cells and stimulated both P815 cells and bone marrow-derived mast cells to produce IL-4, IL-6, and TNF-α in a dose- and time-dependent manner. Cycloheximide as well as sodium cromoglycate blocked the Der f-induced IL-4 production, indicating a de novo protein synthesis process. Supernatants of Der f-stimulated mast cells chemoattracted monocytes and T lymphocytes; they up-regulated the expression of costimulatory B7 molecules, eotaxin, RANTES, monocyte chemoattractant protein 1, and IFN-inducible protein 10 mRNA of alveolar macrophages; they supported PHA-induced T cell proliferation; and they promoted Th2 cell development. Our data indicate that mast cells may be an important cell type during the initiation of Der f sensitization in the airway by modulating the function of alveolar macrophages and T cells.
Evolution of CD8+ T Cell Immunity and Viral Escape Following Acute HIV-1 Infection
Authors: Cao Jianhong , McNevin John , Malhotra Uma , McElrath M. Juliana 
Published: April 2014

Abstract
Induction of HIV-1-specific CD8+ T cells during acute infection is associated with a decline in viremia. The role CD8+ effectors play in subsequently establishing viral set point remains unclear. To address this, we focused on two acutely infected patients with the same initial Tat-specific CD8+ response, analyzing their CD8+ T cell responses longitudinally in conjunction with viral load and sequence evolution. In one patient initiating treatment during acute infection, the frequencies of Tat-specific CD8+ T cells gradually diminished but persisted, and the Tat epitope sequence was unaltered. By contrast, in the second patient who declined treatment, the Tat-specific CD8+ T cells disappeared below detection, in conjunction with Gag-specific CD4+ T cell loss, as plasma viremia reached a set point. This coincided with the emergence of an escape variant within the Tat epitope and an additional Vpr epitope. New CD8+ T cell responses emerged but with no further associated decline in viremia. These findings indicate that, in the absence of treatment, the initial CD8+ T cell responses have the greatest impact on reducing viremia, and that later, continuously evolving responses are less efficient in further reducing viral load. The results also suggest that T cell help may contribute to the antiviral efficiency of the acute CD8+ T cell response.
Intratumor CpG-Oligodeoxynucleotide Injection Induces Protective Antitumor T Cell Immunity
Authors: Lonsdorf Anke S. , Kuekrek Haydar , Stern Britta V. , Boehm Bernhard O. , Lehmann Paul V. , Tary-Lehmann Magdalena 
Published: April 2014

AbstractTumor cells are typically poorly immunogenic. The same mechanisms that evolved to avoid the induction of immune responses against self tissues, and, hence, autoimmune disease, also have to be overcome for immune therapy of cancer. Toll-like receptor-activating microbial products such as CpG motif containing DNA are among the primary stimuli that the immune system uses to distinguish between infectious nonself (that is to be attacked) and noninfectious self (that must not be attacked). We tested in a murine RMA lymphoma/C57BL/6 model whether providing the infectious nonself context in a tumor–by injecting CpG-oligodeoxynucleotides directly into the tumor–would elicit a protective antitumor response. Complete remission of established solid tumors was achieved in immune competent mice, but not in T cell/B cell-deficient RAG-1 knockout mice. Intratumor injection of CpG-oligodeoxynucleotides was shown to induce a tumor-specific CD4+ and CD8+ T cell response of the type 1 effector class, and T cells adoptively transferred the protection to RAG-1 knockout mice. The data show that intratumor injection of CpG-oligodeoxynucleotides is a promising strategy for rendering tumors immunogenic.
Coordinate Regulation of Lymphocyte-Endothelial Interactions by Pregnancy-Associated Hormones
Authors: Chantakru Sirirak , Wang Wan-Chao , van den Heuvel Marianne , Bashar Siamak , Simpson Amanda , Chen Qing , Croy B. Anne , Evans Sharon S. 
Published: April 2014

AbstractPrecursors of uterine NK cells home to the uterus during early pregnancy from multiple lymphohemopoietic sources. In mouse uterine tissue, pregnancy markedly up-regulates both L-selectin- and α4 integrin-dependent adhesion pathways for circulating human CD56bright cells, the phenotype of human uterine NK cells. Based on roles for these adhesion molecules in lymphocyte homing, we examined effects of pregnancy or the steroid hormones 17β-estradiol or progesterone on lymphocyte-endothelial interactions in secondary lymphoid tissues and in uterus. From preimplantation gestation day 3, specialized high endothelial venules in peripheral lymph nodes and Peyer’s patches supported elevated L-selectin and α4β7 integrin-dependent lymphocyte adhesion under shear throughout pregnancy, as compared with high endothelial venules of virgin or postpartum donors. Squamous endothelium from nonlymphoid tissue was not affected. Pregnancy-equivalent endothelial responses were observed in lymph nodes and Peyer’s patches from ovariectomized mice receiving 17β-estradiol and/or progesterone replacement therapy. Adhesion of human CD56bright cells to uteri from pregnant or hormone-treated ovariectomized mice was enhanced through L-selectin- and α4 integrin-dependent mechanisms and involved multiple vascular adhesion molecules including mucosal addressin cell adhesion molecule-1, VCAM-1, and peripheral lymph node addressin. Analysis of Tie2-green fluorescence protein transgenic mice demonstrated that CD56bright cells adhered primarily to vascular endothelium within the decidua basalis. Microdomain localization of adhesion involving large clusters of lymphocytes was induced on uteri from natural matings, but not pseudopregnancy. Steroid hormones also had independent effects on L-selectin function in splenic lymphocytes that mimicked physiological stimulation induced by pregnancy or fever-range temperatures. These results provide the first evidence for coordinated, organ-specific, steroid hormone-induced changes in lymphocyte homing mechanisms that could contribute to local and systemic immune responses during pregnancy.
Immunization with Th-CTL Fusion Peptide and Cytosine-Phosphate-Guanine DNA in Transgenic HLA-A2 Mice Induces Recognition of HIV-Infected T Cells and Clears Vaccinia Virus Challenge
Authors: Daftarian Pirouz , Ali Saima , Sharan Rahul , Lacey Simon F. , La Rosa Corinna , Longmate Jeff , Buck Christopher , Siliciano Robert F. , Diamond Don J. 
Published: April 2014

AbstractWe evaluated immunogenicity of a novel Th-CTL fusion peptide composed of the pan DR Th epitope and a CTL epitope derived from HIV-pol in two transgenic HLA-A*0201/Kb mouse models. The immunogenicity of peptides of this structure is highly dependent on coadministered cytosine-phosphate-guanine DNA. Initial evaluations of peptide-specific immunity are based on results of chromium release assay, intracellular cytokine, and tetramer staining. Significant cytotoxic T cell responses are found upon a single immunization with as low as 0.1 nmol both peptide and cytosine-phosphate-guanine DNA. Splenocytes from immunized mice recognize naturally processed HIV-pol expressed from vaccinia virus (pol-VV). Translation of immunologic criteria into more relevant assays was pursued using systemic challenge of immunized mice with pol-VV. Only mice receiving both peptide and DNA together successfully cleared upward of 6 logs of virus from ovaries, compared with controls. Challenge with pol-VV by intranasal route of intranasal immunized mice showed a significant reduction in the levels of VV in lung compared with naive mice. A convincing demonstration of the relevance of these vaccines is the robust lysis of HIV-infected Jurkat T cells (JA2/R7/Hyg) by immune splenocytes from peptide- and DNA-immunized mice. This surprisingly effective immunization merits consideration for clinical evaluation, because it succeeded in causing immune recognition and lysis of cells infected with its target virus and reduction in titer of highly pathogenic VV.
The Tetraspanin CD81 Regulates the Expression of CD19 During B Cell Development in a Postendoplasmic Reticulum Compartment
Authors: Shoham Tsipi , Rajapaksa Ranjani , Boucheix Claude , Rubinstein Eric , Poe Jonathan C. , Tedder Thomas F. , Levy Shoshana 
Published: April 2014

Abstract
CD81 is a widely expressed tetraspanin that associates in B cells with CD19 in the CD19-CD21-CD81 signaling complex. CD81 is necessary for normal CD19 expression; cd81−/− B cells express lower levels of CD19, especially cd81−/− small pre-BII cells, which are almost devoid of surface CD19. The dependence of CD19 expression on CD81 is specific to this particular tetraspanin since cd9−/− B cells express normal levels of CD19. Furthermore, expression of human CD81 in mouse cd81−/− B cells restored surface CD19 to normal levels. Quantitative analysis of CD19 mRNA demonstrated normal levels, even in cd81−/− pre-BII cells. Analysis of CD19 at the protein level identified two CD19 glycoforms in both wild-type and cd81−/− B cells. The higher Mr glycoform is significantly reduced in cd81−/− B cells and is endoglycosidase H (endo-H) resistant. In contrast, the low Mr glycoform is comparably expressed in cd81−/− and in wild-type B cells and is endo-H sensitive. Because endo-H sensitivity is tightly correlated with endoplasmic reticulum localization, we suggest that the dependency of CD19 expression on CD81 occurs in a postendoplasmic reticulum compartment where CD81 is necessary for normal trafficking or for surface membrane stability of CD19.
Psychological Stress Exerts an Adjuvant Effect on Skin Dendritic Cell Functions In Vivo
Authors: Saint-Mezard Pierre , Chavagnac Cyril , Bosset Sophie , Ionescu Marius , Peyron Eric , Kaiserlian Dominique , Nicolas Jean-Francois , Bérard Frédéric 
Published: April 2014

AbstractPsychological stress affects the pathophysiology of infectious, inflammatory, and autoimmune diseases. However, the mechanisms by which stress could modulate immune responses in vivo are poorly understood. In this study, we report that application of a psychological stress before immunization exerts an adjuvant effect on dendritic cell (DC), resulting in increased primary and memory Ag-specific T cell immune responses. Acute stress dramatically enhanced the skin delayed-type hypersensitivity reaction to haptens, which is mediated by CD8+ CTLs. This effect was due to increased migration of skin DCs, resulting in augmented CD8+ T cell priming in draining lymph nodes and enhanced recruitment of CD8+ T cell effectors in the skin upon challenge. This adjuvant effect of stress was mediated by norepinephrine (NE), but not corticosteroids, as demonstrated by normalization of the skin delayed-type hypersensitivity reaction and DC migratory properties following selective depletion of NE. These results suggest that release of NE by sympathetic nerve termini during a psychological stress exerts an adjuvant effect on DC by promoting enhanced migration to lymph nodes, resulting in increased Ag-specific T cell responses. Our findings may open new ways in the treatment of inflammatory diseases, e.g., psoriasis, allergic contact dermatitis, and atopic dermatitis.
T Cells Induce Extended Class II MHC Compartments in Dendritic Cells in a Toll-Like Receptor-Dependent Manner
Authors: Boes Marianne , Bertho Nicolas , Cerny Jan , Op den Brouw Marjolein , Kirchhausen Tomas , Ploegh Hidde 
Published: April 2014

Abstract
Interaction of Ag-loaded dendritic cells with Ag-specific CD4 T cells induces the formation of long tubular class II MHC-positive compartments that polarize toward the T cell. We show involvement of a Toll-like receptor-mediated signal in this unusual form of intracellular class II MHC trafficking. First, wild-type dendritic cells loaded with LPS-free Ag failed to show formation of class II-positive tubules upon Ag-specific T cell engagement, but did so upon supplementation of the Ag with low concentrations of LPS. Second, Ag-loaded myeloid differentiation factor 88 -deficient dendritic cells failed to form these tubules upon interaction with T cells, regardless of the presence of LPS. Finally, inclusion of a cell-permeable peptide that blocks TNFR-associated factor 6 function, downstream of myeloid differentiation factor 88, blocked T cell-dependent tubulation. A Toll-like receptor-dependent signal is thus required to allow Ag-loaded dendritic cells to respond to T cell contact by formation of extended endosomal compartments. This activation does not result in massive translocation of class II MHC molecules to the cell surface.
T Cell Development in Mice Expressing CD1d Directed by a Classical MHC Class II Promoter
Authors: Forestier Claire , Park Se-Ho , Wei Datsen , Benlagha Kamel , Teyton Luc , Bendelac Albert 
Published: April 2014

AbstractCD1d and nonclassical MHC molecules differ markedly from classical MHC ligands in their ability to promote the selection and differentiation of developing T cells. Whereas classical MHC-restricted T cells have a predominantly naive phenotype and a broad TCR repertoire, most other T cells have a memory and/or NKT phenotype with a restricted repertoire. Because the nonclassical ligands selecting these memory-type cells are expressed by bone marrow-derived cells, it has been suggested that the development of large repertoires of naive-type cells was dependent on the classical MHC expression pattern in the thymus cortex, high on epithelial cells and low on cortical thymocytes. We redirected CD1d expression using the classical MHC II Eα promoter. pEα-CD1d mice lacked memory-type NKT cells, but, surprisingly, they did not acquire the reciprocal ability to select a diverse population of naive CD1d-restricted cells. These findings suggest that, whereas the development of NKT cells is dependent on the pattern of CD1d expression, the absence of a broad, naive CD1d-restricted T cell repertoire may reflect intrinsic limitations of the pool of TCR genes or lipid Ags.