bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective Expression Rather than Specific Function of Txk and Itk Regulate Th1 and Th2 Responses
Authors: Sahu Nisebita , Venegas Ana M. , Jankovic Dragana , Mitzner Wayne , Gomez-Rodriguez Julio , Cannons Jennifer L. , Sommers Connie , Love Paul , Sher Alan , Schwartzberg Pamela L. , August Avery 
Published: April 2014

Abstract
Itk and Txk/Rlk are Tec family kinases expressed in T cells. Itk is expressed in both Th1 and Th2 cells. By contrast, Txk is preferentially expressed in Th1 cells. Although Itk is required for Th2 responses in vivo and Txk is suggested to regulate IFN-γ expression and Th1 responses, it remains unclear whether these kinases have distinct roles in Th cell differentiation/function. We demonstrate here that Txk-null CD4+ T cells are capable of producing both Th1 and Th2 cytokines similar to those produced by wild-type CD4+ T cells. To further examine whether Itk and Txk play distinct roles in Th cell differentiation and function, we examined Itk-null mice carrying a transgene that expresses Txk at levels similar to the expression of Itk in Th2 cells. Using two Th2 model systems, allergic asthma and schistosome egg-induced lung granulomas, we found that the Txk transgene rescued Th2 cytokine production and all Th2 symptoms without notable enhancement of IFN-γ expression. These results suggest that Txk is not a specific regulator of Th1 responses. Importantly, they suggest that Itk and Txk exert their effects on Th cell differentiation/function at the level of expression.
Engineering Antibody Heavy Chain CDR3 to Create a Phage Display Fab Library Rich in Antibodies That Bind Charged Carbohydrates
Authors: Schoonbroodt Sonia , Steukers Mieke , Viswanathan Malini , Frans Nicolas , Timmermans Marie , Wehnert Anita , Nguyen Minh , Ladner Robert Charles , Hoet René M. 
Published: April 2014

Abstract
A number of small charged carbohydrate moieties have been associated with inflammation and cancer. However, the development of therapeutic Abs targeting these moieties has been hampered by their low immunogenicity and their structural relationship to self-Ag. We report the design of an Ab repertoire enriched in Abs binding to small charged carbohydrates and the construction of a human Fab phagemid library, “FAB-CCHO.” This library combines L chain Ig sequences from human donors and H chain synthetic diversity constructed in key Ag contact sites in CDRs 1, 2, and 3 of the human framework VH3–23. The H chain CDR3 has been engineered to enrich the library in Abs that bind charged carbohydrates by the introduction of basic residues at specific amino acid locations. These residues were selected on the basis of anti-carbohydrate Ab sequence alignment. The success of this design is demonstrated by the isolation of phage Abs against charged carbohydrate therapeutic target Ags such as sulfated sialyl-Lewis X glycan and heparan sulfate.
Distinct CDR3 Conformations in TCRs Determine the Level of Cross-Reactivity for Diverse Antigens, but Not the Docking Orientation
Authors: Jones Lindsay L. , Colf Leremy A. , Stone Jennifer D. , Garcia K. Christopher , Kranz David M. 
Published: April 2014

Abstract
T cells are known to cross-react with diverse peptide MHC Ags through their αβ TCR. To explore the basis of such cross-reactivity, we examined the 2C TCR that recognizes two structurally distinct ligands, SIY-Kb and alloantigen QL9-Ld. In this study we characterized the cross-reactivity of several high-affinity 2C TCR variants that contained mutations only in the CDR3α loop. Two of the TCR lost their ability to cross-react with the reciprocal ligand (SIY-Kb), whereas another TCR (m67) maintained reactivity with both ligands. Crystal structures of four of the TCRs in complex with QL9-Ld showed that CDR1, CDR2, and CDR3β conformations and docking orientations were remarkably similar. Although the CDR3α loop of TCR m67 conferred a 2000-fold higher affinity for SIY-Kb, the TCR maintained the same docking angle on QL9-Ld as the 2C TCR. Thus, CDR3α dictated the affinity and level of cross-reactivity, yet it did so without affecting the conserved docking orientation.
Design, Expression, and Processing of Epitomized Hepatitis C Virus-Encoded CTL Epitopes
Authors: Yerly Daniel , Heckerman David , Allen Todd , Suscovich Todd J. , Jojic Nebojsa , Kadie Carl , Pichler Werner J. , Cerny Andreas , Brander Christian 
Published: April 2014

Abstract
Hepatitis C virus (HCV) vaccine efficacy may crucially depend on immunogen length and coverage of viral sequence diversity. However, covering a considerable proportion of the circulating viral sequence variants would likely require long immunogens, which for the conserved portions of the viral genome, would contain unnecessarily redundant sequence information. In this study, we present the design and in vitro performance analysis of a novel “epitome” approach that compresses frequent immune targets of the cellular immune response against HCV into a shorter immunogen sequence. Compression of immunological information is achieved by partial overlapping shared sequence motifs between individual epitopes. At the same time, sequence diversity coverage is provided by taking advantage of emerging cross-reactivity patterns among epitope variants so that epitope variants associated with the broadest variant cross-recognition are preferentially included. The processing and presentation analysis of specific epitopes included in such a compressed, in vitro-expressed HCV epitome indicated effective processing of a majority of tested epitopes, although re-presentation of some epitopes may require refined sequence design. Together, the present study establishes the epitome approach as a potential powerful tool for vaccine immunogen design, especially suitable for the induction of cellular immune responses against highly variable pathogens.
Cannabinoids Inhibit HIV-1 Gp120-Mediated Insults in Brain Microvascular Endothelial Cells
Authors: Lu Tzong-Shi , Avraham Hava Karsenty , Seng Seyha , Tachado Souvenir D. , Koziel Henry , Makriyannis Alexandros , Avraham Shalom 
Published: April 2014

Abstract
HIV-1 infection has significant effect on the immune system as well as on the nervous system. Breakdown of the blood-brain barrier (BBB) is frequently observed in patients with HIV-associated dementia (HAD) despite lack of productive infection of human brain microvascular endothelial cells (HBMEC). Cellular products and viral proteins secreted by HIV-1 infected cells, such as the HIV-1 Gp120 envelope glycoprotein, play important roles in BBB impairment and HIV-associated dementia development. HBMEC are a major component of the BBB. Using cocultures of HBMEC and human astrocytes as a model system for human BBB as well as in vivo model, we show for the first time that cannabinoid agonists inhibited HIV-1 Gp120-induced calcium influx mediated by substance P and significantly decreased the permeability of HBMEC as well as prevented tight junction protein down-regulation of ZO-1, claudin-5, and JAM-1 in HBMEC. Furthermore, cannabinoid agonists inhibited the transmigration of human monocytes across the BBB and blocked the BBB permeability in vivo. These results demonstrate that cannabinoid agonists are able to restore the integrity of HBMEC and the BBB following insults by HIV-1 Gp120. These studies may lead to better strategies for treatment modalities targeted to the BBB following HIV-1 infection of the brain based on cannabinoid pharmacotherapies.
Expansion of Foxp3+ Regulatory T Cells in Mice Infected with the Filarial Parasite Brugia malayi
Authors: McSorley Henry J. , Harcus Yvonne M. , Murray Janice , Taylor Matthew D. , Maizels Rick M. 
Published: April 2014

Abstract
Many helminths, including Brugia malayi, are able to establish long-lived infections in immunocompetent hosts. Growing evidence suggests that the immune system’s failure to eliminate parasites is at least partially due to the effects of regulatory T cells (Tregs). To test whether parasites may directly stimulate host regulatory activity, we infected mice with two key stages of B. malayi. Both mosquito-borne infective larvae and mature adults i.p. introduced were found to preferentially expand the proportion of CD25+Foxp3+ cells within the CD4+ T cell population. The induction of Foxp3 was accompanied by raised CD25, CD103, and CTLA-4 expression, and was shown to be an active process, which accompanied the introduction of live, but not dead parasites. CTLA-4 expression was also markedly higher on Foxp3− cells, suggesting anergized effector populations. Peritoneal lavage CD4+CD25+ cells from infected mice showed similar suppressive activity in vitro to normal splenic “natural” Tregs. Both B. malayi larvae and adults were also able to induce Foxp3 expression in adoptively transferred DO11.10 T cells, demonstrating that filarial infection can influence the development of T cells specific to a third party Ag. In addition, we showed that induction was intact in IL-4R-deficient animals, in the absence of a Th2 or alternatively activated macrophage response. We conclude that filarial infections significantly skew the balance of the host immune system toward Treg expansion and activation, in a manner dependent on live parasites but independent of a concomitant Th2 response.
The Level of Hepatitis B Virus Replication Is Not Affected by Protein ISG15 Modification but Is Reduced by Inhibition of UBP43 (USP18) Expression
Authors: Kim Jung-Hwan , Luo Jiann-Kae , Zhang Dong-Er 
Published: April 2014

Abstract
Hepatitis B virus (HBV) causes both acute and chronic infection of the human liver and is associated with the development of liver cirrhosis and hepatocellular carcinoma. UBP43 (USP18) is known as an ISG15-deconjugating enzyme and an inhibitor of type I IFN signaling independent of its enzyme activity. In this study, we examined the role of these two previously identified functions of UBP43 in the innate immune response to HBV viral infection. As an in vivo HBV replication model system, a replication-competent DNA construct was injected hydrodynamically into the tail veins of mice. Although the lack of ISG15 conjugation in the absence of ISG15-activating enzyme UBE1L (UBA7) did not affect the level of HBV replication, the steady-state level of HBV DNA was substantially reduced in the UBP43-deficient mice in comparison to the wild-type controls. In addition, introduction of short hairpin RNA against UBP43 resulted in substantially lower levels of HBV DNA at day 4 postinjection and higher levels of ISG mRNAs. These results suggest that HBV infection is more rapidly cleared if UBP43 expression is reduced. Furthermore, these results illustrate the therapeutic potential of modulating UBP43 levels in treating viral infection, especially for viruses sensitive to IFN signaling.
Differential Regulation of Chemokines by IL-17 in Colonic Epithelial Cells
Authors: Lee Jimmy W. , Wang Ping , Kattah Michael G. , Youssef Sawsan , Steinman Lawrence , DeFea Kathryn , Straus Daniel S. 
Published: April 2014

Abstract
The IL-23/IL-17 pathway plays an important role in chronic inflammatory diseases, including inflammatory bowel disease. In inflammatory bowel disease, intestinal epithelial cells are an important source of chemokines that recruit inflammatory cells. We examined the effect of IL-17 on chemokine expression of HT-29 colonic epithelial cells. IL-17 strongly repressed TNF-α-stimulated expression of CXCL10, CXCL11, and CCL5, but synergized with TNF-α for induction of CXCL8, CXCL1, and CCL20 mRNAs. For CXCL10, IL-17 strongly inhibited promoter activity but had no effect on mRNA stability. In contrast, for CXCL8, IL-17 slightly decreased promoter activity but stabilized its normally unstable mRNA, leading to a net increase in steady-state mRNA abundance. IL-17 synergized with TNF-α in transactivating the epidermal growth factor receptor (EGFR) and in activating ERK and p38 MAPK. The p38 and ERK pathway inhibitors SB203580 and U0126 reversed the repressive effect of IL-17 on CXCL10 mRNA abundance and promoter activity and also reversed the inductive effect of IL-17 on CXCL8 mRNA, indicating that MAPK signaling mediates both the transcriptional repression of CXCL10 and the stabilization of CXCL8 mRNA by IL-17. The EGFR kinase inhibitor AG1478 partially reversed the effects of IL-17 on CXCL8 and CXCL10 mRNA, demonstrating a role for EGFR in downstream IL-17 signaling. The overall results indicate a positive effect of IL-17 on chemokines that recruit neutrophils (CXCL8 and CXCL1), and Th17 cells (CCL20). In contrast, IL-17 represses expression of CXCL10, CXCL11, and CCR5, three chemokines that selectively recruit Th1 but not other effector T cells.
A Role for cFLIP in B Cell Proliferation and Stress MAPK Regulation
Authors: Zhang Haibing , Rosenberg Stephen , Coffey Francis J. , He You-Wen , Manser Timothy , Hardy Richard R. , Zhang Jianke 
Published: April 2014

Abstract
Fas/Apo-1 signals through the FADD (Fas-associated death domain) adaptor protein, which recruits and activates the apical caspase 8 and leads to apoptosis. Cellular FLIP (cFLIP) is a homolog of caspase 8 and is also capable of binding to FADD. Previous studies suggest that cFLIP could either enhance or inhibit apoptosis and lead to NF-κB and Erk1/2 activation. Like FADD or caspase 8 deficiency, a lack of cFLIP disrupts embryogenesis and T cell proliferation. It has been demonstrated that B cells lacking either FADD or caspase 8 were defective in both Fas-induced apoptosis and TLR-induced proliferation, which indicates that these death-inducing proteins have an additional role in regulating innate immunity. To analyze the function of cFLIP in B cells, conditional deletion of cFLIP was induced by using CD19Cre. The resulting B cell-specific cFLIP-deficient mice were found to have reduced numbers of peripheral B cells that were hypersensitive to Fas-induced apoptosis and impaired in proliferation induced by TLRs and the BCR. Furthermore, there was aberrant expression of costimulatory proteins and activation markers in cFLIP-deficient B cells. Whereas LPS-induced activation of NF-κB and Erk1/2 appears to be unaffected, p38 and Jnk were spontaneously activated and hyperinduced in cFLIP-deficient B cells. Therefore, these data revealed novel functions of cFLIP in B cells.
Progression of Pancreatic Adenocarcinoma Is Significantly Impeded with a Combination of Vaccine and COX-2 Inhibition
Authors: Mukherjee Pinku , Basu Gargi D. , Tinder Teresa L. , Subramani Durai B. , Bradley Judy M. , Arefayene Million , Skaar Todd , De Petris Giovanni 
Published: April 2014

Abstract
With a 5-year survival rate of &lt;5%, pancreatic cancer is one of the most rapidly fatal malignancies. Current protocols for the treatment of pancreas cancer are not as effective as we desire. In this study, we show that a novel Mucin-1 (MUC1)-based vaccine in combination with a cyclooxygenase-2 inhibitor (celecoxib), and low-dose chemotherapy (gemcitabine) was effective in preventing the progression of preneoplastic intraepithelial lesions to invasive pancreatic ductal adenocarcinomas. The study was conducted in an appropriate triple transgenic model of spontaneous pancreatic cancer induced by the KRASG12D mutation and that expresses human MUC1 as a self molecule. The combination treatment elicited robust antitumor cellular and humoral immune responses and was associated with increased apoptosis in the tumor. The mechanism for the increased immune response was attributed to the down-regulation of circulating prostaglandin E2 and indoleamine 2, 3,-dioxygenase enzymatic activity, as well as decreased levels of T regulatory and myeloid suppressor cells within the tumor microenvironment. The preclinical data provide the rationale to design clinical trials with a combination of MUC1-based vaccine, celecoxib, and gemcitabine for the treatment of pancreatic cancer.
IFN-γ Dictates Allograft Fate via Opposing Effects on the Graft and on Recipient CD8 T Cell Responses
Authors: Coley Shana M. , Ford Mandy L. , Hanna Samantha C. , Wagener Maylene E. , Kirk Allan D. , Larsen Christian P. 
Published: April 2014

Abstract
CD8 T cells are necessary for costimulation blockade-resistant rejection. However, the mechanism by which CD8 T cells mediate rejection in the absence of major costimulatory signals is poorly understood. IFN-γ promotes CD8 T cell-mediated immune responses, but IFN-γ-deficient mice show early graft loss despite costimulation blockade. In contrast, we found that IFN-γ receptor knockout mice show dramatically prolonged graft survival under costimulation blockade. To investigate this paradox, we addressed the effects of IFN-γ on T cell alloresponses in vivo independent of the effects of IFN-γ on graft survival. We identified a donor-specific CD8 T cell breakthrough response temporally correlated with costimulation blockade-resistant rejection. Neither IFN-γ receptor knockout recipients nor IFN-γ-deficient recipients showed a CD8 breakthrough response. Graft death on IFN-γ-deficient recipients despite costimulation blockade could be explained by the lack of IFN-γ available to act on the graft. Indeed, the presence of IFN-γ was necessary for graft survival on IFN-γ receptor knockout recipients, as either IFN-γ neutralization or the lack of the IFN-γ receptor on the graft precipitated early graft loss. Thus, IFN-γ is required both for the recipient to mount a donor-specific CD8 T cell response under costimulation blockade as well as for the graft to survive after allotransplantation.
Cancer-Expanded Myeloid-Derived Suppressor Cells Induce Anergy of NK Cells through Membrane-Bound TGF-β1
Authors: Li Hequan , Han Yanmei , Guo Qiuli , Zhang Minggang , Cao Xuetao 
Published: April 2014

Abstract
NK cells, the important effector of innate immunity, play critical roles in the antitumor immunity. Myeloid-derived suppressor cells (MDSC), a population of CD11b+Gr-1+ myeloid cells expanded dramatically during tumor progression, can inhibit T cells and dendritic cells, contributing to tumor immune escaper. However, regulation of NK cell innate function by MDSC in tumor-bearing host needs to be investigated. In this study, we found that the function of NK cells from liver and spleen was impaired significantly in all tumor-bearing models, indicating the impairment of hepatic NK cell function by tumor is a universal phenomenon. Then we prepared the orthotopic liver cancer-bearing mice as tumor model to investigate how hepatic NK cells are impaired. We show that down-regulation of NK cell function is inversely correlated with the marked increase of MDSC in liver and spleen. MDSC inhibit cytotoxicity, NKG2D expression, and IFN-γ production of NK cells both in vitro and in vivo. After incubation with MDSC, NK cells could not be activated to produce IFN-γ. Furthermore, membrane-bound TGF-β1 on MDSC is responsible for MDSC-mediated suppression of NK cells. The impaired function of hepatic NK cells in orthotopic liver cancer-bearing mice could be restored by depletion of MDSC, but not regulatory T cells. Therefore, cancer-expanded MDSC can induce anergy of NK cells via membrane-bound TGF-β1. MDSC, but not regulatory T cells, are main negative regulator of hepatic NK cell function in tumor-bearing host. Our study provides new mechanistic explanations for tumor immune escape.
NKG2A Inhibits Invariant NKT Cell Activation in Hepatic Injury
Authors: Kawamura Toshihiko , Takeda Kazuyoshi , Kaneda Hiroshi , Matsumoto Hiroaki , Hayakawa Yoshihiro , Raulet David H. , Ikarashi Yoshinori , Kronenberg Mitchell , Yagita Hideo , Kinoshita Katsuyuki , Abo Toru , Okumura Ko , Smyth Mark J. 
Published: April 2014

Abstract
Activation of invariant NKT (iNKT) cells in the liver is generally regarded as the critical step for Con A-induced hepatitis, and the role of NK cell receptors for iNKT cell activation is still controversial. In this study we show that blockade of the NKG2A-mediated inhibitory signal with antagonistic anti-NKG2A/C/E mAb (20d5) aggravated Con A-induced hepatitis in wild-type, Fas ligand (FasL)-mutant gld, and IL-4-deficient mice even with NK cell and CD8 T cell depletion, but not in perforin-, IFN-γ-, or IFN-γ- and perforin-deficient mice. Consistently, 20d5 pretreatment augmented serum IFN-γ levels and perforin-dependent cytotoxicity of liver mononuclear cells following Con A injection, but not their FasL/Fas-dependent cytotoxicity. However, blockade of NKG2A-mediated signals during the cytotoxicity effector phase did not augment cytotoxic activity. Activated iNKT cells promptly disappeared after Con A injection, whereas NK1− iNKT cells, which preferentially expressed CD94/NKG2A, predominantly remained in the liver. Pretreatment with 20d5 appeared to facilitate disappearance of iNKT cells, particularly NK1− iNKT cells. Moreover, Con A-induced and α-galactosylceramide-induced hepatic injury was very severe in CD94/NKG2A-deficient DBA/2J mice compared with CD94/NKG2A-intact DBA/2JJcl mice. Overall, these results indicated that a NKG2A-mediated signal negatively regulates iNKT cell activation and hepatic injury.
Cutting Edge: Antigen Presentation to CD8 T Cells after Influenza A Virus Infection
Authors: Ingulli Elizabeth , Funatake Castle , Jacovetty Erica L. , Zanetti Maurizio 
Published: April 2014

Abstract
Influenza A virus infection induces massive inflammation and lung damage. Activation of CD8 T cells by dendritic cells (DCs) is necessary to control disease. We undertook studies to track directly Ag presentation to CD8 T cells in vivo through the first 72 h after infection with OVA-expressing influenza A virus. We found that Ag presentation by DCs occurs strictly in the draining lymph nodes and not within the lung itself. Surprisingly, Ag presentation was found to be mediated by a CD11b+ DC population. Finally, the expression of antigenic complexes on DCs correlated with the location and timing of CD8 T cell activation. These results have implications for approaches to control influenza A virus infection.
Double-Stranded RNA and TGF-α Promote MUC5AC Induction in Respiratory Cells
Authors: Tadaki Hiromi , Arakawa Hirokazu , Mizuno Takahisa , Suzuki Tomoko , Takeyama Kiyoshi , Mochizuki Hiroyuki , Tokuyama Kenichi , Yokota Shumpei , Morikawa Akihiro 
Published: April 2014

Abstract
Viral infection is a major trigger for exacerbation of asthma and induces overproduction of mucins. We investigated whether dsRNA could amplify the induction of mucin by TGF-α in human bronchial epithelial cells, as well as the molecular mechanisms regulating MUC5AC expression. Human pulmonary mucoepidermoid carcinoma (NCI-H292) cells and normal human bronchial epithelial cells were exposed to polyinosinic-cytidyric acid (poly(I:C)) and TGF-α. Then, MUC5AC protein production, mRNA expression, and promoter activity were evaluated. Cells were pretreated with a selective inhibitor of ERK, and phosphorylation of ERK was examined by Western blotting. Furthermore, the expression of MAPK phosphatase 3 (MKP3) mRNA was evaluated and the effect of MKP3 overexpression was assessed. Poly(I:C) synergistically increased MUC5AC induction by TGF-α in both NCI-H292 and normal human bronchial epithelial cells. This increase was dependent on MUC5AC gene transcription. A MEK1/2 inhibitor (U0126) significantly inhibited MUC5AC production. Phosphorylation of ERK was enhanced by poly(I:C). TGF-α stimulation up-regulated MKP3 mRNA expression, while costimulation with poly(I:C) inhibited this up-regulation dose-dependently. Enhanced expression of MUC5AC mRNA by poly(I:C) in wild-type cells was completely suppressed in cells transfected with the MKP3 expression vector. dsRNA can synergistically amplify the induction of MUC5AC mucin by TGF-α. This synergistic effect on MUC5AC production may be due to enhanced activation of ERK through inhibition of MKP3 by poly(I:C).