bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abnormal NF-κB Function Characterizes Human Type 1 Diabetes Dendritic Cells and Monocytes
Authors: Mollah Zia U. A. , Pai Saparna , Moore Craig , O’Sullivan Brendan J. , Harrison Matthew J. , Peng Judy , Phillips Karen , Prins Johannes B. , Cardinal John , Thomas Ranjeny 
Published: April 2014

Abstract
Dendritic cell (DC) differentiation is abnormal in type 1 diabetes mellitus (T1DM). However, the nature of the relationship between this abnormality and disease pathogenesis is unknown. We studied the LPS response in monocytes and monocyte-derived DCs isolated from T1DM patients and from non-T1DM controls. In T1DM patients, late LPS-mediated nuclear DNA binding by RelA, p50, c-Rel, and RelB was impaired as compared with type 2 DM, rheumatoid arthritis, and healthy subjects, associated with impaired DC CD40 and MHC class I induction but normal cytokine production. In TIDM monocytes, RelA and RelB were constitutively activated, and the src homology 2 domain-containing protein tyrosine phosphatase (SHP-1), a negative regulator of NF-κB, was overexpressed. Addition of sodium stibogluconate, a SHP-1 inhibitor, to DCs differentiating from monocyte precursors restored their capacity to respond to LPS in ∼60% of patients. The monocyte and DC NF-κB response to LPS is thus a novel phenotypic and likely pathogenetic marker for human T1DM. SHP-1 is at least one NF-κB regulatory mechanism which might be induced as a result of abnormal inflammatory signaling responses in T1DM monocytes.
Phylogenetic Conservation of Glycoprotein 96 Ability to Interact with CD91 and Facilitate Antigen Cross-Presentation
Authors: Robert Jacques , Ramanayake Thaminda , Maniero Gregory D. , Morales Heidi , Chida Asiya S. 
Published: April 2014

Abstract
Although the ability of gp96 to activate APCs and generate CD8 CTLs against peptides they chaperone through interaction with the endocytic receptors CD91 is supported by solid evidence, its biological relevance in immune surveillance is debated. We have used an evolutionary approach to determine whether gp96 interacts with receptors expressed on APCs and promotes MHC class I cross-presentation of minor histocompatibility Ags (H-Ags) to CTLs in the frog Xenopus. We show that in Xenopus gp96 binds the CD91 homolog at the surface of peritoneal leukocytes, and that this binding is inhibited by molar excess of unlabeled gp96 or the CD91 ligand α2-macroglobulin, by anti-CD91 Ab and by the specific CD91 antagonist receptor-associated protein. Surface binding followed by internalization of gp96 was confirmed by fluorescent microscopy. Furthermore, adoptive transfer of peritoneal leukocytes pulsed with as little as 800 ng of gp96 chaperoning minor H-Ags, but not minor H-Ag-free gp96, induces potent CD8 T cell infiltration and Ag-specific accelerated rejection of minor H-locus disparate skin grafts. Inhibition of gp96-CD91 interaction by pretreatment with anti-CD91 Ab and receptor-associated protein impairs both CD8 T cell infiltration and acute skin graft rejection. These data provide evidence of the conserved ability of gp96 to facilitate cross-presentation of chaperoned Ags by interacting with CD91. The persistence of this biological process for &gt;350 million years that separate mammals and amphibians from a common ancestor strongly supports the proposition that gp96 and CD91 are critically involved in immune surveillance.
Expansion of Effector Memory TCR Vβ4+CD8+ T Cells Is Associated with Latent Infection-Mediated Resistance to Transplantation Tolerance
Authors: Stapler Dale , Lee Eun D. , Selvaraj Saranya A. , Evans Andrew G. , Kean Leslie S. , Speck Samuel H. , Larsen Christian P. , Gangappa Shivaprakash 
Published: April 2014

Abstract
Therapies that control largely T cell-dependent allograft rejection in humans also possess the undesirable effect of impairing T cell function, leaving transplant recipients susceptible to opportunistic viruses. Prime among these opportunists are the ubiquitous herpesviruses. To date, studies are lacking that address the effect of viruses that establish a true latent state on allograft tolerance or the effect of tolerance protocols on the immune control of latent viruses. By using a mixed chimerism-based tolerance-induction protocol, we found that mice undergoing latent infection with γHV68, a murine γ-herpesvirus closely related to human γ-herpesviruses such as EBV and Kaposi’s sarcoma-associated herpesvirus, significantly resist tolerance to allografts. Limiting the degree of virus reactivation or innate immune response did not reconstitute chimerism in latently infected mice. However, γHV68-infected mice showed increased frequency of CD8+ T cell alloreactivity and, interestingly, expansion of virus-induced, alloreactive, “effector/effector memory” TCR Vβ4+CD8+ T cells driven by the γHV68-M1 gene was associated with resistance to tolerance induction in studies using γHV68-M1 mutant virus. These results define the viral gene and immune cell types involved in latent infection-mediated resistance to allograft tolerance and underscore the influence of latent herpesviruses on allograft survival.
Selection of an Antibody Library Identifies a Pathway to Induce Immunity by Targeting CD36 on Steady-State CD8α+ Dendritic Cells
Authors: Tagliani Elisa , Guermonprez Pierre , Sepúlveda Jorge , López-Bravo María , Ardavín Carlos , Amigorena Sebastian , Benvenuti Federica , Burrone Oscar R. 
Published: April 2014

Abstract
Improvement of the strategy to target tumor Ags to dendritic cells (DCs) for immunotherapy requires the identification of the most appropriate ligand/receptor pairing. We screened a library of Ab fragments on mouse DCs to isolate new potential Abs capable of inducing protective immune responses. The screening identified a high-affinity Ab against CD36, a multi-ligand scavenger receptor primarily expressed by the CD8α+ subset of conventional DCs. The Ab variable regions were genetically linked to the model Ag OVA and tested in Ag presentation assays in vitro and in vivo. Anti-CD36-OVA was capable of delivering exogenous Ags to the MHC class I and MHC class II processing pathways. In vivo, immunization with anti-CD36-OVA induced robust activation of naive CD4+ and CD8+ Ag-specific T lymphocytes and the differentiation of primed CD8+ T cells into long-term effector CTLs. Vaccination with anti-CD36-OVA elicited humoral and cell-mediated protection from the growth of an Ag-specific tumor. Notably, the relative efficacy of targeting CD11c/CD8α+ via CD36 or DEC205 was qualitatively different. Anti-DEC205-OVA was more efficient than anti-CD36-OVA in inducing early events of naive CD8+ T cell activation. In contrast, long-term persistence of effector CTLs was stronger following immunization with anti-CD36-OVA and did not require the addition of exogenous maturation stimuli. The results identify CD36 as a novel potential target for immunotherapy and indicate that the outcome of the immune responses vary by targeting different receptors on CD8α+ DCs.
Differential Activation of Dual Promoters Alters Dβ2 Germline Transcription during Thymocyte Development
Authors: McMillan Ruth E. , Sikes Michael L. 
Published: April 2014

Abstract
Ag receptor genes are assembled through somatic rearrangements of V, D, and J gene segments. This process is directed in part by transcriptional enhancers and promoters positioned within each gene locus. Whereas enhancers coordinate reorganization of large chromatin stretches, promoters are predicted to facilitate the accessibility of proximal downstream gene segments. In TCR β locus, rearrangement initiates at two D-J cassettes, each of which exhibits transcriptional activity coincident with DJ rearrangement in CD4/CD8 double-negative pro-T cells. Consistent with a model of promoter-facilitated recombination, assembly of the DJβ1 cassette is dependent on a Dβ1 promoter (PDβ1) positioned immediately 5′ of the D. Assembly of DJβ2 proceeds independent from that of DJβ1, albeit with less efficiency. To gain insight into the mechanisms that selectively alter D usage, we have defined transcriptional regulation at Dβ2. We find that both DJβ cassettes generate germline messages in murine CD44+CD25− double-negative 1 cells. However, transcription of unrearranged DJβ2 initiates at multiple sites 400–550 bp downstream of the Dβ2. Unexpectedly, loci from which germline promoter activity has been deleted by DJ rearrangement redirect transcription to sites immediately 5′ of the new DJβ2 joint. Our analyses suggest that 3′-PDβ2 activity is largely controlled by NF-κB RelA, whereas 5′-PDβ2 activity directs germline transcription of DJβ2 joints from initiator elements 76 bp upstream of the Dβ2 5′ recombination signal sequence. The unique organization and timing of Dβ2 promoter activity are consistent with a model in which promoter placement selectively regulates the rearrangement potential of Dβ2 during TCR β locus assembly.
Through Regulation of TCR Expression Levels, anIdd7Region Gene(s) Interactively Contributes to the Impaired Thymic Deletion of Autoreactive Diabetogenic CD8+ T Cells in Nonobese Diabetic Mice
Authors: Serreze David V. , Choisy-Rossi Caroline Morgane , Grier Alexandra E. , Holl T. Mathew , Chapman Harold D. , Gahagan J. Reed , Osborne Melissa A. , Zhang Weidong , King Benjamin L. , Brown Aaron , Roopenian Derry , Marron Michele P. 
Published: April 2014

AbstractWhen expressed in NOD, but not C57BL/6 (B6) genetic background mice, the common class I variants encoded by the H2g7 MHC haplotype aberrantly lose the ability to mediate the thymic deletion of autoreactive CD8+ T cells contributing to type 1 diabetes (T1D). This indicated some subset of the T1D susceptibility (Idd) genes located outside the MHC of NOD mice interactively impair the negative selection of diabetogenic CD8+ T cells. In this study, using both linkage and congenic strain analyses, we demonstrate contributions from a polymorphic gene(s) in the previously described Idd7 locus on the proximal portion of Chromosome 7 predominantly, but not exclusively, determines the extent to which H2g7 class I molecules can mediate the thymic deletion of diabetogenic CD8+ T cells as illustrated using the AI4 TCR transgenic system. The polymorphic Idd7 region gene(s) appears to control events that respectively result in high vs low expression of the AI4 clonotypic TCR α-chain on developing thymocytes in B6.H2g7 and NOD background mice. This expression difference likely lowers levels of the clonotypic AI4 TCR in NOD, but not B6.H2g7 thymocytes, below the threshold presumably necessary to induce a signaling response sufficient to trigger negative selection upon Ag engagement. These findings provide further insight to how susceptibility genes, both within and outside the MHC, may interact to elicit autoreactive T cell responses mediating T1D development in both NOD mice and human patients.
Glycosylation-Dependent Interactions of C-Type Lectin DC-SIGN with Colorectal Tumor-Associated Lewis Glycans Impair the Function and Differentiation of Monocyte-Derived Dendritic Cells
Authors: Nonaka Motohiro , Ma Bruce Yong , Murai Ryuuya , Nakamura Natsuko , Baba Makoto , Kawasaki Nobuko , Hodohara Keiko , Asano Shinji , Kawasaki Toshisuke 
Published: April 2014

Abstract
Dendritic cells (DCs) are APCs that play an essential role by bridging innate and adaptive immunity. DC-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) is one of the major C-type lectins expressed on DCs and exhibits high affinity for nonsialylated Lewis (Le) glycans. Recently, we reported the characterization of oligosaccharide ligands expressed on SW1116, a typical human colorectal carcinoma recognized by mannan-binding protein, which is a serum C-type lectin and has similar carbohydrate-recognition specificities as DC-SIGN. These tumor-specific oligosaccharide ligands were shown to comprise clusters of tandem repeats of Lea/Leb epitopes. In this study, we show that DC-SIGN is involved in the interaction of DCs with SW1116 cells through the recognition of aberrantly glycosylated forms of Lea/Leb glycans on carcinoembryonic Ag (CEA) and CEA-related cell adhesion molecule 1 (CEACAM1). DC-SIGN ligands containing Lea/Leb glycans are also highly expressed on primary cancer colon epithelia but not on normal colon epithelia, and DC-SIGN is suggested to be involved in the association between DCs and colorectal cancer cells in situ by DC-SIGN recognizing these cancer-related Le glycan ligands. Furthermore, when monocyte-derived DCs (MoDCs) were cocultured with SW1116 cells, LPS-induced immunosuppressive cytokines such as IL-6 and IL-10 were increased. The effects were significantly suppressed by blocking Abs against DC-SIGN. Strikingly, LPS-induced MoDC maturation was inhibited by supernatants of cocultures with SW1116 cells. Our findings imply that colorectal carcinomas affecting DC function and differentiation through interactions between DC-SIGN and colorectal tumor-associated Le glycans may induce generalized failure of a host to mount an effective antitumor response.
Human Lymphatic Endothelial Cells Express Multiple Functional TLRs
Authors: Pegu Amarendra , Qin Shulin , Fallert Junecko Beth A. , Nisato Riccardo E. , Pepper Michael S. , Reinhart Todd A. 
Published: April 2014

Abstract
The lymphatic endothelium is the preferred route for the drainage of interstitial fluid from tissues and also serves as a conduit for peripheral dendritic cells (DCs) to reach draining lymph nodes. Lymphatic endothelial cells (LECs) are known to produce chemokines that recruit Ag-loaded DCs to lymphatic vessels and therefore are likely to regulate the migration of DCs to lymph nodes. TLRs are immune receptors that recognize pathogen associated molecular patterns and then signal and stimulate production of inflammatory chemokines and cytokines that contribute to innate and adaptive immune responses. TLRs are known to be expressed by a wide variety of cell types including leukocytes, epithelial cells, and endothelial cells. Because the TLR expression profile of LECs remains largely unexamined, we have undertaken a comprehensive study of the expression of TLR1–10 mRNAs and protein in primary human dermal (HD) and lung LECs as well as in htert-HDLECs, which display a longer life-span than HDLECs. We found that all three cell types expressed TLR1–6 and TLR9. The responsiveness of these LECs to a panel of ligands for TLR1–9 was measured by real-time RT-PCR, ELISA, and flow cytometry, and revealed that the LECs responded to most but not all TLR ligands by increasing expression of inflammatory chemokines, cytokines, and adhesion molecules. These findings provide insight into the ability of cells of the lymphatic vasculature to respond to pathogens and potential vaccine adjuvants and shape peripheral environments in which DCs will acquire Ag and environmental cues.
Stimulation of Enhanced CD8 T Cell Responses Following Immunization with a Hyper-Antigen Secreting Intracytosolic Bacterial Pathogen
Authors: Smithey Megan J. , Brandt Suzanne , Freitag Nancy E. , Higgins Darren E. , Bouwer H. G. Archie 
Published: April 2014

AbstractThe intracytosolic niche for replication of Listeria monocytogenes (Lm) facilitates delivery of bacteria-derived Ags into the MHC class I pathway for subsequent stimulation of CD8 effector T cells. Using Lm strains that are equivalent for in vivo virulence yet express marked differences in the level of secretion of a protective target Ag, we have evaluated how these specific differences in secretion levels influences the magnitude and effector function of Ag-specific CD8 T cell responses following Lm injection. Immunization with low doses of a hyperantigen-secreting Lm strain stimulated enhanced target-Ag specific CD8 T cell responses compared with the magnitude stimulated following immunization with the same dose of wild-type Lm. The enhanced determinant-specific response was also evident by in vivo CTL activity, increased numbers of memory cells 4 wk following immunization, and enhanced antilisterial protection following a challenge infection. Initiation of antibiotic treatment 24 h following infection with wild-type Lm markedly reduced the magnitude of the effector CD8 T cell response. In contrast, antibiotic treatment initiated 24 h following immunization with the hyperantigen secreting strain of Lm did not impact the frequency of the target-Ag specific CD8 T cells. Thus, immunization with a low dose of a hyperantigen secreting Lm strain, followed by antibiotic treatment to limit the extent of the infection, may represent a safe strategy for the stimulation of enhanced effector CD8 T cell responses to specific Ag by a rLm vaccine.
Mycobacterial Lipopeptides Elicit CD4+ CTLs in Mycobacterium tuberculosis-Infected Humans
Authors: Bastian Max , Braun Tobias , Bruns Heiko , Röllinghoff Martin , Stenger Steffen 
Published: April 2014

Abstract
In searching for immunogenic molecules with the potential to induce protective immune responses against tuberculosis, we developed an ex vivo model to study frequency, phenotype, and effector functions of human T lymphocytes recognizing hydrophobic Ags of Mycobacterium tuberculosis (M.Tb). To obtain unbiased results, we characterized T lymphocytes responding to a crude cell wall extract (chloroform methanol extract of M.Tb (M.Tb-CME)) containing a broad spectrum of mycobacterial glycolipids and lipopeptides. A significant proportion of T lymphocytes recognized M.Tb-CME (290 IFN-γ+ T cells/105 PBMCs) and developed to effector memory cells as determined by the expression of CD45RO and the chemokine receptors CXCR3 and CCR5. Expanded lymphocytes fulfilled all criteria required for an efficient immune response against tuberculosis: 1) release of macrophage-activating Th1 cytokines and chemokines required for the spatial organization of local immune responses, 2) cytolytic activity against Ag-pulsed macrophages, and 3) recognition of infected macrophages and killing of the intracellular bacteria. Phenotypically, M.Tb-CME-expanded cells were CD4+ and MHC class II restricted, challenging current concepts that cytotoxic and antimicrobial effector cells are restricted to the CD8+ T cell subset. Pretreatment of M.Tb-CME with protease or chemical delipidation abrogated the biological activity, suggesting that responses were directed toward mycobacterial lipopeptides. These findings suggest that lipidated peptides are presented by M.Tb-infected macrophages and elicit CD4+ cytolytic and antimicrobial T lymphocytes. Our data support an emerging concept to include hydrophobic microbial Ags in vaccines against tuberculosis.
Lymphotoxin-α1β2 and LIGHT Induce Classical and Noncanonical NF-κB-Dependent Proinflammatory Gene Expression in Vascular Endothelial Cells
Authors: Madge Lisa A. , Kluger Martin S. , Orange Jordan S. , May Michael J. 
Published: April 2014

Abstract
Activation of the classical and noncanonical NF-κB pathways by ligation of the lymphotoxin (LT)-β receptor (LTβR) plays a crucial role in lymphoid organogenesis and in the generation of ectopic lymphoid tissue at sites of chronic inflammation. Within these microenvironments, LTβR signaling regulates the phenotype of the specialized high endothelial cells. However, the direct effects of LTβR ligation on endothelial cells remain unclear. We therefore questioned whether LTβR ligation could directly activate endothelial cells and regulate classical and noncanonical NF-κB-dependent gene expression. We demonstrate that the LTβR ligands LIGHT and LTα1β2 activate both NF-κB pathways in HUVECs and human dermal microvascular endothelial cells (HDMEC). Classical pathway activation was less robust than TNF-induced signaling; however, only LIGHT and LTα1β2 and not TNF activated the noncanonical pathway. LIGHT and LTα1β2 induced the expression of classical NF-κB-dependent genes in HUVEC, including those encoding the adhesion molecules E-selectin, ICAM-1, and VCAM-1. Consistent with this stimulation, LTβR ligation up-regulated T cell adhesion to HUVEC. Furthermore, the homeostatic chemokine CXCL12 was up-regulated by LIGHT and LTα1β2 but not TNF in both HUVEC and HDMEC. Using HUVEC retrovirally transduced with dominant negative IκB kinase α, we demonstrate that CXCL12 expression is regulated by the noncanonical pathway in endothelial cells. Our findings therefore demonstrate that LTβR ligation regulates gene expression in endothelial cells via both NF-κB pathways and we identify CXCL12 as a bona fide noncanonical NF-κB-regulated gene in these cells.
Transcriptional Complex Formation of c-Fos, STAT3, and Hepatocyte NF-1α Is Essential for Cytokine-Driven C-Reactive Protein Gene Expression
Authors: Nishikawa Teppei , Hagihara Keisuke , Serada Satoshi , Isobe Tomoyasu , Matsumura Atsumi , Song Jian , Tanaka Toshio , Kawase Ichiro , Naka Tetsuji , Yoshizaki Kazuyuki 
Published: April 2014

Abstract
C-reactive protein (CRP) is a sensitive marker and mediator of inflammation, whereas IL-6 blocking therapy can normalize serum levels of CRP in chronic inflammatory diseases. We investigated the precise synergistic induction mechanism of CRP gene expression by IL-1 and IL-6 in Hep3B cells. In the early induction phase, IL-1 inhibited IL-6-mediated CRP gene expression, and NF-κB p65 inhibited the luciferase activity of pGL3-CRP by IL-1 plus IL-6 even in the presence of overexpressed STAT3. In the late induction phase, we focused on JNK and p38 activated by IL-1. SP600125 reduced the expression of the CRP gene induced by IL-1 plus IL-6. Unexpectedly, overexpression of c-Fos dramatically enhanced the luciferase activity by IL-1 and IL-6 even though the CRP gene has no AP-1 response element (RE) in its promoter. The augmentative effect of c-Fos required the presence of STAT3 and 3′-hepatocyte NF-1 (HNF-1) RE, which were eliminated by dominant negative STAT3 and HNF-1α, respectively. SB203580 inhibited the phosphorylation of c-Fos enhanced by IL-1 plus IL-6, and diminished expression of the CRP gene. Immunoprecipitation, Western blot analysis, the Supershift assay using a CRP oligonucleotide containing STAT3 and 3′-HNF-1 RE, and the chromatin immunoprecipitation assay demonstrated that c-Fos/STAT3/HNF-1α forms a complex on the CRP gene promoter. Because human fetus liver cells failed to express c-Fos/STAT3/HNF-1α showed no CRP production, transcriptional complex formation of c-Fos/STAT3/HNF-1α is essential for the synergistic induction of CRP gene expression by IL-1 plus IL-6. Our findings fully explain the clinical results of IL-6 blocking therapy and are expected to contribute to the development of a therapeutic strategy for chronic inflammatory diseases.