bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Tumoricidal Activity of Memory CD8+ T Cells Is Hampered by Persistent Systemic Antigen, but Full Functional Capacity Is Regained in an Antigen-Free Environment
Authors: den Boer Annemieke Th. , van Mierlo Geertje J. D. , Fransen Marieke F. , Melief Cornelis J. M. , Offringa Rienk , Toes René E. M. 
Published: April 2014

AbstractNaive T cells can be tolerized in the periphery by diverse mechanisms. However, the extent to which memory T cells are susceptible to tolerance induction is less well defined. Vaccination of mice with a minimal CTL epitope derived from human adenovirus type 5 E1A in IFA s.c. readily tolerizes naive as well as recently activated CD8+ T cells due to the overwhelming systemic and persistent presence of the peptide. We have now studied the effect of this peptide on established memory cells, which were induced at least 50 days before by virus vaccination. Memory cells did not undergo peripheral deletion and kept their ability to produce IFN-γ as well as their cytolytic activity in response to Ag directly ex vivo. However, memory CTL responses in virus vaccinated mice injected with peptide ceased to control tumor outgrowth. Interestingly, functional capacities were regained when T cells were transferred to an Ag-free environment in vivo as determined by their ability to reject an otherwise lethal tumor challenge. Together, these findings indicate that memory CTL responses can be functionally incapacitated, but are not, in contrast to naive or recently activated T cells, irreversibly tolerized by persistent systemic Ag, as memory T cells quickly regain effector function upon disappearance of the Ag.
IL-9-Induced Expansion of B-1b Cells Restores Numbers but Not Function of B-1 Lymphocytes in xid Mice
Authors: Knoops Laurent , Louahed Jamila , Renauld Jean-Christophe 
Published: April 2014

Abstract
Mice expressing the X-linked immunodeficiency (xid) mutation lack functional Bruton’s tyrosine kinase and were shown to be specifically deficient in peritoneal B-1 lymphocytes. We have previously shown that IL-9, a cytokine produced by TH2 lymphocytes, promotes B-1 cell expansion in vivo. To determine whether IL-9 overexpression might compensate the xid mutation for B-1 lymphocyte development, we crossed xid mice with IL-9-transgenic mice. In this model, IL-9 restored normal numbers of mature peritoneal B-1 cells that all belonged to the CD5− B-1b subset. Despite this normal B-1 lymphocyte number, IL-9 failed to restore classical functions of B-1 cells, namely, the production of natural IgM Abs, the T15 Id Ab response to phosphorylcholine immunization, and the antipolysaccharide humoral response against Streptococcus pneumoniae. By using bromelain-treated RBC, we showed that the antigenic repertoire of these IL-9-induced B-1b lymphocytes was different from the repertoire of classical CD5+ B-1a cells, indicating that the lack of B-1 function by B-1b cells is associated with distinct Ag specificities. Taken together, our data show that B-1b cell development can restore the peritoneal B-1 population in xid mice but that these B-1b cells are functionally distinct from CD5+ B-1a lymphocytes.
CD1d-Independent NKT Cells in β2-Microglobulin-Deficient Mice Have Hybrid Phenotype and Function of NK and T Cells
Authors: Maeda Motoi , Shadeo Ashleen , MacFadyen Anna M. , Takei Fumio 
Published: April 2014

AbstractUnlike CD1d-restricted NK1.1+TCRαβ+ (NKT) cells, which have been extensively studied, little is known about CD1d-independent NKT cells. To characterize their functions, we analyzed NKT cells in β2-microglobulin (β2m)-deficient B6 mice. They are similar to NK cells and expressed NK cell receptors, including Ly49, CD94/NKG2, NKG2D, and 2B4. NKT cells were found in normal numbers in mice that are deficient in β2m, MHC class II, or both. They were also found in the male HY Ag-specific TCR-transgenic mice independent of positive or negative selection in the thymus. For functional analysis of CD1d-independent NKT cells, we developed a culture system in which CD1d-independent NKT cells, but not NK, T, or most CD1d-restricted NKT cells, grew in the presence of an intermediate dose of IL-2. IL-2-activated CD1d-indpendent NKT cells were similar to IL-2-activated NK cells and efficiently killed the TAP-mutant murine T lymphoma line RMA-S, but not the parental RMA cells. They also killed β2m-deficient Con A blasts, but not normal B6 Con A blasts, indicating that the cytotoxicity is inhibited by MHC class I on target cells. IL-2-activated NKT cells expressing transgenic TCR specific for the HY peptide presented by Db killed RMA-S, but not RMA, cells. They also killed RMA (H-2b) cells that were preincubated with the HY peptide. NKT cells from β2m-deficient mice, upon CD3 cross-linking, secreted IFN-γ and IL-2, but very little IL-4. Thus, CD1d-independent NKT cells are significantly different from CD1d-restricted NKT cells. They have hybrid phenotypes and functions of NK cells and T cells.
Human CD4+CD25+ Regulatory T Cells Share Equally Complex and Comparable Repertoires with CD4+CD25− Counterparts
Authors: Kasow Kimberly A. , Chen Xiaohua , Knowles James , Wichlan David , Handgretinger Rupert , Riberdy Janice M. 
Published: April 2014

Abstract
CD4+CD25+ T cells are critical mediators of peripheral immune tolerance. However, many developmental and functional characteristics of these cells are unknown, and knowledge of human regulatory T cells is particularly limited. To better understand how human CD4+CD25+ T cells develop and function, we examined the diversity of CD4+CD25+ and CD4+CD25− T cell repertoires in both thymus and peripheral blood. Levels of T receptor excision circles (TREC) were comparable in purified CD4+CD25+ and CD4+CD25− thymic populations, but were significantly higher than those in samples derived from peripheral blood, consistent with murine studies demonstrating thymic development of CD4+CD25+ regulatory T cells. Surprisingly, CD4+CD25− T cells isolated from peripheral blood had greater TREC quantities than their CD4+CD25+ counterparts, supporting the possibility of extrathymic expansion as well. CD4+CD25+ and CD4+CD25− T cells from a given individual showed overlapping profiles with respect to diversity by Vβ staining and spectratyping. Interestingly, CD4+CD25+ T cells have lower quantities of CD3 than CD4+CD25− T cells. Collectively, these data suggest that human CD4+CD25+ T cells recognize a similar array of Ags as CD4+CD25− T cells. However, reduced levels of TCR on regulatory T cells suggest different requirements for activation and may contribute to how the immune system regulates whether a particular response is suppressed or augmented.
Transcriptional Activation of the SH2D2A Gene Is Dependent on a Cyclic Adenosine 5′-Monophosphate-Responsive Element in the Proximal SH2D2A Promoter
Authors: Dai Ke-Zheng , Johansen Finn-Eirik , Kolltveit Kristin Melkevik , Aasheim Hans-Christian , Dembic Zlatko , Vartdal Frode , Spurkland Anne 
Published: April 2014

Abstract
The SH2D2A gene, encoding the T cell-specific adapter protein (TSAd), is rapidly induced in activated T cells. In this study we investigate the regulation of the SH2D2A gene in Jurkat T cells and in primary T cells. Reporter gene assays demonstrated that the proximal 1-kb SH2D2A promoter was constitutively active in Jurkat TAg T cells and, to a lesser extent, in K562 myeloid cells, Reh B cells, and 293T fibroblast cells. The minimal SH2D2A promoter was located between position −236 and −93 bp from the first coding ATG, and transcriptional activity in primary T cells depended on a cAMP response element (CRE) centered around position −117. Nuclear extracts from Jurkat TAg cells and activated primary T cells contained binding activity to this CRE, as observed in an EMSA. Consistent with this observation, we found that a cAMP analog was a very potent inducer of SH2D2A mRNA expression in primary T cells as measured by real-time RT-PCR. Furthermore, activation of SH2D2A expression by CD3 stimulation required cAMP-dependent protein kinase activity. Thus, transcriptional regulation of the SH2D2A gene in activated T cells is critically dependent on a CRE in the proximal promoter region.
Lipopolysaccharide-Binding Protein Critically Regulates Lipopolysaccharide-Induced IFN-β Signaling Pathway in Human Monocytes
Authors: Kato Atsushi , Ogasawara Takahisa , Homma Toshiki , Saito Hirohisa , Matsumoto Kenji 
Published: April 2014

AbstractLPS binding to Toll-like receptor 4 induces a large number of genes through activation of NF-κB and IFN-regulatory factor-3 (IRF-3). However, no previous reports have tested the role of serum proteins in LPS-induced gene expression profiles. To investigate how serum proteins affect LPS-induced signaling, we investigated LPS-inducible genes in PBMC using an oligonucleotide probe-array system. Approximately 120 genes up-regulated by LPS were hierarchically divided into two clusters. Induction of one cluster, containing only IFN-inducible genes, was serum dependent. Real-time PCR analysis confirmed that IFN-inducible genes were induced only in the presence of serum, whereas inflammatory genes were induced both in the presence and absence of serum. Further analysis demonstrated that addition of LPS-binding protein (LBP), but not of soluble CD14 to the serum-free medium enabled the induction of IFN-inducible genes and IFN-β itself by LPS in human monocytes. The mRNAs for IFN-β and IFN-inducible genes were induced by LPS only in the presence of serum from LBP+/+ mice, and not in the presence of serum from LBP−/− mice. Blocking experiments also confirmed the involvement of LBP in this phenomenon. Immunoblotting analysis showed that phosphorylation of c-Jun N-terminal kinase, p38, IRF-3, tyrosine kinase 2, and STAT1 by LPS, but not of NF-κB and extracellular signal-regulated kinase was abrogated in the absence of LBP. This critical role for LBP implies the presence of possible mechanisms linking LBP to the intracellular signaling between Toll-like receptor 4 and IRF-3, leading to the induction of IFN-β by LPS.
Lysine-Dependent Multipoint Binding of theBorrelia burgdorferiVirulence Factor Outer Surface Protein E to the C Terminus of Factor H
Authors: Alitalo Antti , Meri Taru , Chen Tong , Lankinen Hilkka , Cheng Zhu-Zhu , Jokiranta T. Sakari , Seppälä Ilkka J. T. , Lahdenne Pekka , Hefty P. Scott , Akins Darrin R. , Meri Seppo 
Published: April 2014

AbstractSerum resistance, an important virulence determinant of Borrelia burgdorferi sensu lato strains belonging to the Borrelia afzelii and B. burgdorferi sensu stricto genotypes, is related to binding of the complement inhibitor factor H to the spirochete surface protein outer surface protein E (OspE) and its homologues. In this study, we show that the C-terminal short consensus repeats 18–20 of both human and mouse factor H bind to OspE. Analogously, factor H-related protein 1, a distinct plasma protein with three short consensus repeat domains homologous to those in factor H, bound to OspE. Deleting 15-aa residues (region V) from the C terminus of the OspE paralog P21 (a 20.7-kDa OspE-paralogous surface lipoprotein in the B. burgdorferi sensu stricto 297 strain) abolished factor H binding. However, C-terminal peptides from OspE, P21, or OspEF-related protein P alone and the C-terminal deletion mutants of P21 inhibited factor H binding to OspE only partially when compared with full-length P21 or its N-terminal mutant. Alanine substitution of amino acids in peptides from the key binding regions of the OspE family indicated that several lysine residues are required for factor H binding. Thus, the borrelial OspE family proteins bind the C inhibitor factor H via multiple sites in a lysine-dependent manner. The C-terminal site V (Ala151-Lys166) is necessary, but not sufficient, for factor H binding in both rodents and humans. Identification of the necessary binding sites forms a basis for the development of vaccines that block the factor H-OspE interaction and thereby promote the killing of Borreliae.
Filaria-Induced Immune Evasion: Suppression by the Infective Stage of Brugia malayi at the Earliest Host-Parasite Interface
Authors: Semnani Roshanak Tolouei , Law Melissa , Kubofcik Joseph , Nutman Thomas B. 
Published: April 2014

Abstract
To assess the physiologic interactions between the infective stage of Brugia malayi—one of the extracellular parasites responsible for lymphatic filariasis in humans—and the APC with which they come in contact during their development and routes of travel, we have investigated the interaction between the infective stage (L3) of B. malayi and human Langerhans cells (LC) in the skin. Our data indicate that live L3 result in increased migration of LC from the epidermis without affecting the viability of these cells and up-regulation of the IL-18 cytokine involved in LC migration. Live L3 also result in down-regulation of MHC class I and II on the LC cell surface. Additionally, microarray data indicate that live L3 significantly down-regulated expression of IL-8 as well as of multiple genes involved in Ag presentation, reducing the capacity of LC to induce CD4+ T cells in allogeneic MLR, and thus resulting in a decreased ability of LC to promote CD4+ T cell proliferation and production of IFN-γ and IL-10. These data suggest that L3 exert a down-regulatory response in epidermal LC that leads to a diminished capacity of these cells to activate CD4+ T cells.
Immunogenicity of Recombinant Adenovirus Serotype 35 Vaccine in the Presence of Pre-Existing Anti-Ad5 Immunity
Authors: Barouch Dan H. , Pau Maria G. , Custers Jerome H. H. V. , Koudstaal Wouter , Kostense Stefan , Havenga Menzo J. E. , Truitt Diana M. , Sumida Shawn M. , Kishko Michael G. , Arthur Janelle C. , Korioth-Schmitz Birgit , Newberg Michael H. , Gorgone Darci A. , Lifton Michelle A. , Panicali Dennis L. , Nabel Gary J. , Letvin Norman L. , Goudsmit Jaap 
Published: April 2014

Abstract
The high prevalence of pre-existing immunity to adenovirus serotype 5 (Ad5) in human populations may substantially limit the immunogenicity and clinical utility of recombinant Ad5 vector-based vaccines for HIV-1 and other pathogens. A potential solution to this problem is to use vaccine vectors derived from adenovirus (Ad) serotypes that are rare in humans, such as Ad35. However, cross-reactive immune responses between heterologous Ad serotypes have been described and could prove a major limitation of this strategy. In particular, the extent of immunologic cross-reactivity between Ad5 and Ad35 has not previously been determined. In this study we investigate the impact of pre-existing anti-Ad5 immunity on the immunogenicity of candidate rAd5 and rAd35 vaccines expressing SIV Gag in mice. Anti-Ad5 immunity at levels typically found in humans dramatically blunted the immunogenicity of rAd5-Gag. In contrast, even high levels of anti-Ad5 immunity did not substantially suppress Gag-specific cellular immune responses elicited by rAd35-Gag. Low levels of cross-reactive Ad5/Ad35-specific CD4+ T lymphocyte responses were observed, but were insufficient to suppress vaccine immunogenicity. These data demonstrate the potential utility of Ad35 as a candidate vaccine vector that is minimally suppressed by anti-Ad5 immunity. Moreover, these studies suggest that using Ad vectors derived from immunologically distinct serotypes may be an effective and general strategy to overcome the suppressive effects of pre-existing anti-Ad immunity.
Dual Role of TLR2 and Myeloid Differentiation Factor 88 in a Mouse Model of Invasive Group B Streptococcal Disease
Authors: Mancuso Giuseppe , Midiri Angelina , Beninati Concetta , Biondo Carmelo , Galbo Roberta , Akira Shizuo , Henneke Philipp , Golenbock Douglas , Teti Giuseppe 
Published: April 2014

AbstractToll-like receptors (TLRs) are involved in pathogen recognition by the innate immune system. Different TLRs and the adaptor molecule myeloid differentiation factor 88 (MyD88) were previously shown to mediate in vitro cell activation induced by group B streptococcus (GBS). The present study examined the potential in vivo roles of TLR2 and MyD88 during infection with GBS. When pups were infected locally with a low bacterial dose, none of the TLR2- or MyD88-deficient mice, but all of the wild-type ones, were able to prevent systemic spread of GBS from the initial focus. Bacterial burden was higher in MyD88- than in TLR2-deficient mice, indicating a more profound defect of host defense in the former animals. In contrast, a high bacterial dose induced high level bacteremia in both mutant and wild-type mice. Under these conditions, however, TLR2 or MyD88 deficiency significantly protected mice from lethality, concomitantly with decreased circulating levels of TNF-α and IL-6. Administration of anti-TNF-α Abs to wild-type mice could mimic the effects of TLR2 or MyD88 deficiency and was detrimental in the low dose model, but protective in the high dose model. In conclusion, these data highlight a dual role of TLR2 and MyD88 in the host defense against GBS sepsis and strongly suggest TNF-α as the molecular mediator of bacterial clearance and septic shock.
Transient and Selective NF-κB p65 Serine 536 Phosphorylation Induced by T Cell Costimulation Is Mediated by IκB Kinase β and Controls the Kinetics of p65 Nuclear Import
Authors: Mattioli Ivan , Sebald Andrea , Bucher Cyril , Charles Roch-Philippe , Nakano Hiroyasu , Doi Takahiro , Kracht Michael , Schmitz M. Lienhard 
Published: April 2014

AbstractFull transcriptional activity of the nuclear, DNA-bound form of NF-κB requires additional posttranslational modifications. In this study, we systematically mapped the T cell costimulation-induced phosphorylation sites within the C-terminal half of the strongly trans-activating NF-κB p65 subunit and identified serine 536 as the main phosphorylation site. The transient kinetics of serine 536 phosphorylation paralleled the kinetics of IκBα and IκB kinase (IKK) phosphorylation and also mirrored the principle of T cell costimulation. The TCR-induced pathway leading to serine 536 phosphorylation is regulated by the kinases Cot (Tpl2), receptor interacting protein, protein kinase Cθ, and NF-κB-inducing kinase, but is independent from the phosphatidylinositol 3-kinase/Akt signaling pathway. Loss-of-function and gain-of-function experiments showed phosphorylation of p65 serine 536 by IKKβ, but not by IKKα. Phosphorylation occurs within the cytoplasmic and intact NF-κB/IκBα complex and requires prior phosphorylation of IκBα at serines 32 and 36. Reconstitution of p65−/− cells either with wild-type p65 or a p65 mutant containing a serine to alanine mutation revealed the importance of this phosphorylation site for cytosolic IκBα localization and the kinetics of p65 nuclear import.
Studies of Congenic Lines in the Brown Norway Rat Model of Th2-Mediated Immunopathological Disorders Show That the Aurothiopropanol Sulfonate-Induced Immunological Disorder (Aiid3) Locus on Chromosome 9 Plays a Major Role Compared toAiid2on Chromosome 10
Authors: Mas Magali , Cavaillès Pierre , Colacios Céline , Subra Jean-François , Lagrange Dominique , Calise Maryline , Christen Marie-Odile , Druet Philippe , Pelletier Lucette , Gauguier Dominique , Fournié Gilbert J. 
Published: April 2014

AbstractBrown Norway (BN) rats treated with aurothiopropanol-sulfonate (Atps) constitute a model of Th2-mediated immunological disorders associated with elevated IgE responses and renal IgG deposits. Using F2 offspring between Atps-susceptible BN and Atps-resistant Lewis rats, we had previously mapped three quantitative trait loci on chromosomes 9, 10, and 20 for which BN alleles increased susceptibility to Atps-induced immunological disorders (Aiid). In this study we have used congenic lines for the latter two quantitative trait loci, formerly called Atps2 and Atps3 and now named Aiid2 (chromosome 10) and Aiid3 (chromosome 9), for fine mapping and characterization of their impact on Atps-triggered reactions. In Aiid2 congenic lines, the gene(s) controlling part of the IgE response to Atps was mapped to an ∼7-cM region, which includes the IL-4 cytokine gene cluster. Two congenic lines in which the introgressed segments shared only a portion of this 7-cM region, showed an intermediate IgE response, indicating the involvement of several genes within this region. Results from BN rats congenic for the Lewis Aiid3 locus, which we mapped to a 1.2-cM interval, showed a stronger effect of this region. In this congenic line, the Atps-triggered IgE response was 10-fold lower than in the BN parental strain, and glomerular IgG deposits were either absent or dramatically reduced. Further genetic and functional dissections of these loci should provide insights into pathways that lead to Th2-adverse reactions.
The Transmembrane CXC-Chemokine Ligand 16 Is Induced by IFN-γ and TNF-α and Shed by the Activity of the Disintegrin-Like Metalloproteinase ADAM10
Authors: Abel Soeren , Hundhausen Christian , Mentlein Rolf , Schulte Alexander , Berkhout Theo A. , Broadway Neil , Hartmann Dieter , Sedlacek Radek , Dietrich Sebastian , Muetze Barbara , Schuster Bjoern , Kallen Karl-Josef , Saftig Paul , Rose-John Stefan , Ludwig Andreas 
Published: April 2014

Abstract
The novel CXC-chemokine ligand 16 (CXCL16) functions as transmembrane adhesion molecule on the surface of APCs and as a soluble chemoattractant for activated T cells. In this study, we elucidate the mechanism responsible for the conversion of the transmembrane molecule into a soluble chemokine and provide evidence for the expression and shedding of CXCL16 by fibroblasts and vascular cells. By transfection of human and murine CXCL16 in different cell lines, we show that soluble CXCL16 is constitutively generated by proteolytic cleavage of transmembrane CXCL16 resulting in reduced surface expression of the transmembrane molecule. Inhibition experiments with selective hydroxamate inhibitors against the disintegrin-like metalloproteinases a disintegrin and metalloproteinase domain (ADAM)10 and ADAM17 suggest that ADAM10, but not ADAM17, is involved in constitutive CXCL16 cleavage. In addition, the constitutive cleavage of transfected human CXCL16 was markedly reduced in embryonic fibroblasts generated from ADAM10-deficient mice. By induction of murine CXCL16 in ADAM10-deficient fibroblasts with IFN-γ and TNF-α, we show that endogenous ADAM10 is indeed involved in the release of endogenous CXCL16. Finally, the shedding of endogenous CXCL16 could be reconstituted by retransfection of ADAM10-deficient cells with ADAM10. Analyzing the expression and release of CXCXL16 by cultured vascular cells, we found that IFN-γ and TNF-α synergize to induce CXCL16 mRNA. The constitutive shedding of CXCL16 from the endothelial cell surface is blocked by inhibitors of ADAM10 and is independent of additional inhibition of ADAM17. Hence, during inflammation in the vasculature, ADAM10 may act as a CXCL16 sheddase and thereby finely control the expression and function of CXCL16 in the inflamed tissue.