bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Single Polymorphism Disrupts the Killer Ig-Like Receptor 2DL2/2DL3 D1 Domain
Authors: VandenBussche Christopher J. , Dakshanamurthy Sivanesan , Posch Phillip E. , Hurley Carolyn Katovich 
Published: April 2014

Abstract
Genetic polymorphisms found in the killer Ig-like receptor (KIR), two domains, long cytoplasmic tail 2/3 (KIR2DL2/3) locus are responsible for the differential binding of KIR2DL2/3 allelic products with their HLA-C ligands and have been associated with the resolution of hepatitis C infection. In our study, a KIR CD3ζ fusion-binding assay did not detect any interaction between the KIR2DL2*004 extracellular domain and several putative KIR2DL2/3 ligands. To determine the amino acid polymorphism(s) responsible for the KIR2DL2*004 phenotype, we mutated the polymorphic residues of full-length KIR and expressed them in human Jurkat cells. Flow cytometry analysis failed to detect the surface expression of receptors containing a threonine at position 41 (T41), a polymorphism specific to KIR2DL2*004. Confocal microscopy showed that receptors containing T41 were retained inside the cell and had a perinuclear localization, possibly indicating that their extracellular domain was misfolded. Most KIR2DL2/3 alleles possess an arginine at position 41 (R41), and we predicted through molecular modeling and demonstrated by mutagenesis that R41 most likely interacts with the nearby residues Y77 and D47. Interaction between these residues would maintain C strand contact with the C′ and F strands of the D1 domain β-sheet. Furthermore, R41 and Y77 are conserved in the C and F strand amino acid alignments of Ig-like superfamily members, and may therefore be necessary for the structural integrity of other immune response proteins. Our data indicate that the extracellular T41 polymorphism encoded by the KIR2DL2*004 allele most likely results in misfolding of the D1 domain and complete intracellular retention of the receptor.
Differential and Nonredundant Roles of Phospholipase Cγ2 and Phospholipase Cγ1 in the Terminal Maturation of NK Cells
Authors: Regunathan Jeyarani , Chen Yuhong , Kutlesa Snjezana , Dai Xuezhi , Bai Li , Wen Renren , Wang Demin , Malarkannan Subramaniam 
Published: April 2014

AbstractNK cells play a central role in mediating innate immune responses. Activation of NK cells results in cytotoxicity, cytokine, and chemokine secretions. In this study, we show that in mice with targeted deletion of phospholipase Cγ (PLCγ)2, one of the key signal transducers, there are profound effects on the development and terminal maturation of NK cells. Lack of PLCγ2 significantly impaired the ability of lineage-committed NK precursor cells to acquire subset-specific Ly49 receptors and thereby terminal maturation of NK cells. Overexpression of isozyme, PLCγ1, in PLCγ2-deficient NK cells resulted in the successful Ly49 acquisition and terminal maturation of the NK cells; however, it could only partially rescue NKG2D-mediated cytotoxicity with no cytokine production. Furthermore, PLCγ2-deficient NK cells failed to mediate antitumor cytotoxicity and inflammatory cytokine production, displaying a generalized hyporesponsiveness. Our results strongly demonstrate that PLCγ1 and PLCγ2 play nonredundant and obligatory roles in NK cell ontogeny and in its effector functions.
Two-Sided Roles of IL-27: Induction of Th1 Differentiation on Naive CD4+ T Cells versus Suppression of Proinflammatory Cytokine Production Including IL-23-Induced IL-17 on Activated CD4+ T Cells Partially Through STAT3-Dependent Mechanism
Authors: Yoshimura Takeru , Takeda Atsunobu , Hamano Shinjiro , Miyazaki Yoshiyuki , Kinjyo Ichiko , Ishibashi Tatsuro , Yoshimura Akihiko , Yoshida Hiroki 
Published: April 2014

AbstractRecent lines of evidence have demonstrated that IL-27, a newly identified IL-12-related cytokine, has two apparently conflicting roles in immune responses: one as an initiator of Th1 responses and the other as an attenuator of inflammatory cytokine production. Although the IL-27-mediated Th1 initiation mechanism has been elucidated, little is known about the molecular basis for the suppression of cytokine production. In the present study, we demonstrated that IL-27 suppressed the production of various proinflammatory cytokines by fully activated CD4+ T cells while it had no effect on the cytokine production by CD4+ T cells at early phases of activation. IL-27 also suppressed IL-17 production by activated CD4+ T cells, thereby counteracting IL-23, another IL-12-related cytokine with proinflammatory effects. In fully activated CD4+ T cells, STAT3 was preferentially activated by IL-27 stimulation, whereas both STAT1 and 3 were activated by IL-27 in early activated CD4+ T cells. Lack of STAT3 in fully activated cells impaired the suppressive effects of IL-27. These data indicated that the preferential activation of STAT3 in fully activated CD4+ T cells plays an important role in the cytokine suppression by IL-27/WSX-1.
Transitional B Cell Fate Is Associated with Developmental Stage-Specific Regulation of Diacylglycerol and Calcium Signaling upon B Cell Receptor Engagement
Authors: Hoek Kristen L. , Antony Pierre , Lowe John , Shinners Nicholas , Sarmah Bhaskarjyoti , Wente Susan R. , Wang Demin , Gerstein Rachel M. , Khan Wasif N. 
Published: April 2014

AbstractFunctional peripheral mature follicular B (FoB) lymphocytes are thought to develop from immature transitional cells in a BCR-dependent manner. We have previously shown that BCR cross-linking in vitro results in death of early transitional (T1) B cells, whereas late transitional (T2) B cells survive and display phenotypic characteristics of mature FoB cells. We now demonstrate that diacylglycerol (DAG), a lipid second messenger implicated in cell survival and differentiation, is produced preferentially in T2 compared with T1 B cells upon BCR cross-linking. Consistently, inositol 1,4,5-triphosphate is also produced preferentially in T2 compared with T1 B cells. Unexpectedly, the initial calcium peak appears similar in both T1 and T2 B cells, whereas sustained calcium levels are higher in T1 B cells. Pretreatment with 2-aminoethoxydiphenylborate, an inhibitor of inositol 1,4,5-triphosphate receptor-mediated calcium release, and verapamil, an inhibitor of L-type calcium channels, preferentially affects T1 B cells, suggesting that distinct mechanisms regulate calcium mobilization in each of the two transitional B cell subsets. Finally, BCR-mediated DAG production is dependent upon Bruton’s tyrosine kinase and phospholipase C-γ2, enzymes required for the development of FoB from T2 B cells. These results suggest that calcium signaling in the absence of DAG-mediated signals may lead to T1 B cell tolerance, whereas the combined action of DAG and calcium signaling is necessary for survival and differentiation of T2 into mature FoB lymphocytes.
The DMα and DMβ Chain Cooperate in the Oxidation and Folding of HLA-DM
Authors: van Lith Marcel , Benham Adam M. 
Published: April 2014

AbstractHLA-DM (DM) is a heterodimeric MHC molecule that catalyzes the peptide loading of classical MHC class II molecules in the endosomal/lysosomal compartments of APCs. Although the function of DM is well-established, little is known about how DMα and β-chains fold, oxidize, and form a complex in the endoplasmic reticulum (ER). In this study, we show that glycosylation promotes, but is not essential for, DMαβ ER exit. However, glycosylation of DMα N15 is required for oxidation of the α-chain. The DMα and β-chains direct each others fate: single DMα chains cannot fully oxidize without DMβ, while DMβ forms disulfide-linked homodimers without DMα. Correct oxidation and subsequent ER egress depend on the unique DMβ C25 and C35 residues. This suggests that the C25-C35 disulfide bond in the peptide-binding domain overcomes the need for stabilizing peptides required by other MHC molecules.
Lectin Pathway of Bony Fish Complement: Identification of Two Homologs of the Mannose-Binding Lectin Associated with MASP2 in the Common Carp (Cyprinus carpio)
Authors: Nakao Miki , Kajiya Takayuki , Sato Yuho , Somamoto Tomonori , Kato-Unoki Yoko , Matsushita Misao , Nakata Munehiro , Fujita Teizo , Yano Tomoki 
Published: April 2014

Abstract
The lectin pathway of complement is considered to be the most ancient complement pathway as inferred from identification of ancient homologs of mannose-binding lectin (MBL) and MBL-associated serine proteases (MASPs) in some invertebrates. MBL homologs with galactose selectivity and an MASP3-like sequence also occur in bony fish, linking the evolution of the lectin complement pathway from invertebrates to higher vertebrates. However, these cannot be considered authentic complement components until confirmatory functional evidence is obtained. Here, we report the isolation and characterization of two MBL homologs from a cyprinid teleost, the common carp, Cyprinus carpio. One, designated GalBL, corresponds to the MBL-like molecule with the galactose specificity. The other is an authentic MBL with mannose specificity. Both were found to associate with a serine protease that cleaves native human C4 into C4b but not C4i with a hydrolyzed thioester. Molecular cloning and phylogenetic analysis revealed this C4-activating protease to be carp MASP2, indicating that MASP2 arose before the emergence of bony fish. Database mining of MBL-like genes reveals that MBL and GalBL genes are arranged in tandem in the zebrafish genome and that both lectins are conserved in the distantly related puffer fish. These results imply that bony fish have developed a diverged set of MBL homologs that function in the lectin complement pathway.
Mucosal Vaccine Targeting Improves Onset of Mucosal and Systemic Immunity to Botulinum Neurotoxin A
Authors: Maddaloni Massimo , Staats Herman F. , Mierzejewska Dagmara , Hoyt Teri , Robinson Amy , Callis Gayle , Kozaki Shunji , Kiyono Hiroshi , McGhee Jerry R. , Fujihashi Kohtaro , Pascual David W. 
Published: April 2014

Abstract
Absence of suitable mucosal adjuvants for humans prompted us to consider alternative vaccine designs for mucosal immunization. Because adenovirus is adept in binding to the respiratory epithelium, we tested the adenovirus 2 fiber protein (Ad2F) as a potential vaccine-targeting molecule to mediate vaccine uptake. The vaccine component (the host cell-binding domain to botulinum toxin (BoNT) serotype A) was genetically fused to Ad2F to enable epithelial binding. The binding domain for BoNT was selected because it lies within the immunodominant H chain as a β-trefoil (Hcβtre) structure; we hypothesize that induced neutralizing Abs should be protective. Mice were nasally immunized with the Hcβtre or Hcβtre-Ad2F, with or without cholera toxin (CT). Without CT, mice immunized with Hcβtre produced weak secretory IgA (sIgA) and plasma IgG Ab response. Hcβtre-Ad2F-immunized mice produced a sIgA response equivalent to mice coimmunized with CT. With CT, Hcβtre-Ad2F-immunized mice showed a more rapid onset of sIgA and plasma IgG Ab responses that were supported by a mixed Th1/Th2 cells, as opposed to mostly Th2 cells by Hcβtre-dosed mice. Mice immunized with adjuvanted Hcβtre-Ad2F or Hcβtre were protected against lethal BoNT serotype A challenge. Using a mouse neutralization assay, fecal Abs from Hcβtre-Ad2F or Hcβtre plus CT-dosed mice could confer protection. Parenteral immunization showed that the inclusion of Ad2F enhances anti-Hcβtre Ab titers even in the absence of adjuvant. This study shows that the Hcβtre structure can confer protective immunity and that use of Hcβtre-Ad2F gives more rapid and sustained mucosal and plasma Ab responses.
Release of LL-37 by Activated Human Vγ9Vδ2 T Cells: A Microbicidal Weapon against Brucella suis
Authors: Dudal Sherri , Turriere Chrystell , Bessoles Stephanie , Fontes Pascaline , Sanchez Françoise , Liautard Janny , Liautard Jean-Pierre , Lafont Virginie 
Published: April 2014

Abstract
Human Vγ9Vδ2 T cells play a crucial role in early immune response to intracellular pathogens. Moreover, in brucellosis, these cells are drastically increased in the peripheral blood of patients during the acute phase of infection. In vitro, Vγ9Vδ2 T cells are capable of inhibiting Brucella growth and development through a combination of mechanisms: 1) cytotoxicity, 2) macrophage activation and bactericidal activity through cytokine and chemokine secretion, and 3) antibacterial effects. We previously described that antibacterial factors were found in supernatants from activated Vγ9Vδ2 T cells. In this study, we show that Vγ9Vδ2 T cells express the human cathelicidin hCAP18 and its mature form, known as LL-37, is released upon activation of Vγ9Vδ2 T cells. We also show that LL-37 has an antibacterial effect on Brucella suis. Overall, our results demonstrate that LL-37 is a soluble factor responsible for a part of the bactericidal activity of Vγ9Vδ2 T cells.
Differential Modulation of Human Lactoferrin Activity against Both R5 and X4-HIV-1 Adsorption on Epithelial Cells and Dendritic Cells by Natural Antibodies
Authors: Saidi Héla , Eslaphazir Jobin , Carbonneil Cédric , Carthagena Laetitia , Requena Mary , Nassreddine Nadine , Belec Laurent 
Published: April 2014

Abstract
Human lactoferrin (Lf) is an iron binding glycoprotein that is present in several mucosal secretions. Many biological functions have been ascribed to Lf. In the present study, we showed that Lf limited specifically adsorption of R5- and X4-HIV-1-free particles on endometrial epithelial HEC-1A cells, by inhibiting virus adsorption on heparan-sulfated proteoglycans. But, Lf did not interfere with both R5 and X4-HIV transcytosis. We showed also the efficacy of Lf in preventing R5 and X4-HIV capture by dendritic cells. Conversely, we demonstrated that Lf-reacting natural Abs (NAbs) present within i.v. Ig-enhanced HIV attachment on dendritic cells by forming HIV-Lf-NAbs. HIV particles were able to directly interact with Lf following its interaction with NAbs. We also found Lf-reacting natural Abs within cervicovaginal secretions, suggesting the existence of Lf-NAbs complexes in women genital tract in vivo. In conclusion, this study highlights Lf as a potent microbicides and reports new function for NAbs within the genital compartment that may compartment that may abolish the inhibitory activity of microbicide compounds. Thus, we proposed a model in which Lf would appear as a double-edged sword that could have beneficial or detrimental effects depending on both cellular and molecular environments. This study highlights the use of Lf derivates as microbicide candidates to limit such interferences.
Involvement of the Urokinase Kringle Domain in Lipopolysaccharide-Induced Acute Lung Injury
Authors: Wang Xue-Qing , Bdeir Khalil , Yarovoi Sergei , Cines Douglas B. , Fang Wenfeng , Abraham Edward 
Published: April 2014

AbstractUrokinase plasminogen activator (uPA) plays a major role in fibrinolytic processes and also can potentiate LPS-induced neutrophil activation through interactions with its kringle domain (KD). To investigate the role of the uPA KD in modulating acute inflammatory processes in vivo, we cloned and then developed Abs to the murine uPA KD. Increased pulmonary expression of uPA and the uPA KD was present in the lungs after LPS exposure. Administration of anti-kringle Abs diminished LPS-induced up-regulation of uPA and uPA KD in the lungs, and also decreased the severity of LPS-induced acute lung injury, as determined by development of lung edema, pulmonary neutrophil accumulation, histology, and lung IL-6, MIP-2, and TNF-α cytokine levels. These proinflammatory effects of the uPA KD appeared to be mediated through activation of Akt and NF-κB. The present studies indicate that the uPA KD plays a major role in the development of TLR4-mediated acute inflammatory processes, including lung injury. Blockade of the uPA KD may prevent the development or ameliorate the severity of acute lung injury induced through TLR4-dependent mechanisms, such as would occur in the setting of Gram-negative pulmonary or systemic infection.
Type I IFN Modulates Host Defense and Late Hyperinflammation in Septic Peritonitis
Authors: Weighardt Heike , Kaiser-Moore Simone , Schlautkötter Sylvia , Rossmann-Bloeck Tanja , Schleicher Ulrike , Bogdan Christian , Holzmann Bernhard 
Published: April 2014

Abstract
TLRs are considered important for the control of immune responses during endotoxic shock or polymicrobial sepsis. Signaling by TLRs may proceed through the adapter proteins MyD88 or TIR domain-containing adaptor inducinng IFN-β. Both pathways can lead to the production of type I IFNs (IFN-αβ). In the present study, the role of the type I IFN pathway for host defense and immune pathology in sepsis was investigated using a model of mixed bacterial peritonitis. Systemic levels of IFN-αβ protein were markedly elevated during septic peritonitis. More detailed analyses revealed production of IFN-β, but not IFN-α subtypes, and identified CD11b+CD11c− macrophage-like cells as major producers of IFN-β. The results further demonstrate that in IFN-αβ receptor I chain (IFNARI)-deficient mice, the early recruitment of neutrophils to the infected peritoneal cavity was augmented, most likely due to an increased local production of MCP-1 and leukotriene B4. In the absence of IFNARI, peritoneal neutrophils also exhibited enhanced production of reactive oxygen intermediates and elevated expression of Mac-1. Conversely, administration of recombinant IFN-β resulted in reduced leukotriene B4 levels and decreased peritoneal neutrophil recruitment and activation. Analysis of the cytokine response to septic peritonitis revealed that IFNARI deficiency strongly attenuated late, but not early, hyperinflammation. In accordance with these findings, bacterial clearance and overall survival of IFNARI−/− mice were improved. Therefore, the present study reveals critical functions of the type I IFN pathway during severe mixed bacterial infections leading to sepsis. The results suggest that type I IFN exerts predominantly adverse effects under these conditions.
Induction of IL-10 Suppressors in Lung Transplant Patients by CD4+25+ Regulatory T Cells through CTLA-4 Signaling
Authors: Bharat Ankit , Fields Ryan C. , Trulock Elbert P. , Patterson G. Alexander , Mohanakumar Thalachallour 
Published: April 2014

AbstractT cell-mediated autoimmunity to collagen V (col-V), a sequestered yet immunogenic self-protein, can induce chronic lung allograft rejection in rodent models. In this study we characterized the role of CD4+CD25+ regulatory T cells (Tregs) in regulating col-V autoimmunity in human lung transplant (LT) recipients. LT recipients revealed a high frequency of col-V-reactive, IL-10-producing CD4+ T cells (TIL-10 cells) with low IL-2-, IFN-γ-, IL-5-, and no IL-4-producing T cells. These TIL-10 cells were distinct from Tregs because they lacked constitutive expression of both CD25 and Foxp3. Expansion of TIL-10 cells during col-V stimulation in vitro involved CTLA-4 on Tregs, because both depleting and blocking Tregs with anti-CTLA4 F(ab′)2 mAbs resulted in loss of TIL-10 cells with a concomitant increase in IFN-γ producing Th1 cells (TIFN-γ cells). A Transwell culture of col-V-specific TIL-10 cells with Th1 cells (those generated in absence of Tregs) from the same patient resulted in marked inhibition of IFN-γ and proliferation of TIFN-γ cells, which was reversed by neutralizing IL-10. Furthermore, the TIL-10 cells were HLA class II restricted because blocking HLA class II on APCs resulted in the loss of IL-10 production. Chronic lung allograft rejection was associated with the loss of Tregs with a concomitant decrease in TIL-10 cells and an increase in TIFN-γ cells. We conclude that LT patients have col-V-specific T cells that can be detected in the peripheral blood. The predominant col-V-specific T cells produce IL-10 that suppresses autoreactive Th1 cells independently of direct cellular contact. Tregs are pivotal for the induction of these “suppressor” TIL-10 cells.
Reinstalling Antitumor Immunity by Inhibiting Tumor-Derived Immunosuppressive Molecule IDO through RNA Interference
Authors: Zheng Xiufen , Koropatnick James , Li Mu , Zhang Xusheng , Ling Fengjun , Ren Xiubao , Hao Xishan , Sun Hongtao , Vladau Costin , Franek Jacob A. , Feng Biao , Urquhart Bradley L. , Zhong Robert , Freeman David J. , Garcia Bertha , Min Wei-Ping 
Published: April 2014

Abstract
Tumor-derived immune suppression is a major impediment to successful immune/gene cancer therapy. In the present study, we describe a novel strategy to disrupt tumor-derived immune suppression by silencing a tolerogenic molecule of tumor origin, IDO, using small interfering RNA (siRNA). Silencing of IDO in B16F10 cells in vitro using IDO-siRNA prevented catabolism of tryptophan and inhibited apoptosis of T cells. IDO-siRNA treatment of B16F10 cells in vitro inhibited subsequent growth, tumor formation, and the size of tumor formed, by those cells when transplanted into host mice. In vivo treatment of B16F10 tumor-bearing mice successfully postponed tumor formation time and significantly decreased tumor size. Furthermore, in vivo IDO-siRNA treatment resulted in recovery of T cells responses and enhancement of tumor-specific killing. Thus, silencing IDO may break tumor-derived immune suppression. These data indicate that RNA interference has potential to enhance cancer therapy by reinstalling anticancer immunity.
Human CD4+ T Cells Lyse Target Cells via Granzyme/Perforin upon Circumvention of MHC Class II Restriction by an Antibody-Like Immunoreceptor
Authors: Hombach Andreas , Köhler Heike , Rappl Gunter , Abken Hinrich 
Published: April 2014

AbstractImmune elimination of tumor cells requires the close cooperation between CD8+ CTL and CD4+ Th cells. We circumvent MHC class II-restriction of CD4+ T cells by expression of a recombinant immunoreceptor with an Ab-derived binding domain redirecting specificity. Human CD4+ T cells grafted with an immunoreceptor specific for carcinoembryonic Ag (CEA) are activated to proliferate and secrete cytokines upon binding to CEA+ target cells. Notably, redirected CD4+ T cells mediate cytolysis of CEA+ tumor cells with high efficiencies. Lysis by redirected CD4+ T cells is independent of death receptor signaling via TNF-α or Fas, but mediated by perforin and granzyme because cytolysis is inhibited by blocking the release of cytotoxic granules, but not by blocking of Fas ligand or TNF-α. CD4+ T cells redirected by Ab-derived immunoreceptors in a MHC class II-independent fashion substantially extend the power of an adoptive, Ag-triggered immunotherapy not only by CD4+ T cell help, but also by cytolytic effector functions. Because cytolysis is predominantly mediated via granzyme/perforin, target cells that are resistant to death receptor signaling become sensitive to a cytolytic attack by engineered CD4+ T cells.