bluuebunny/crossref_metadata_2025_split huggingface dataset:
CXCR3/CXCR3 Ligand Biological Axis Impairs RENCA Tumor Growth by a Mechanism of Immunoangiostasis
Authors: Pan Judong , Burdick Marie D. , Belperio John A. , Xue Ying Ying , Gerard Craig , Sharma Sherven , Dubinett Steven M. , Strieter Robert M. 
Published: April 2014

AbstractMetastatic renal cell carcinoma (RCC) responds poorly to chemo- or radiation therapy but appears to respond to systemic immunotherapy (i.e., IL-2 and/or IFN-α), albeit with only 5–10% durable response. The CXCR3/CXCR3 ligand biological axis plays an important role in mediating type 1 cytokine-dependent cell-mediated immunity, which could be beneficial for attenuating RCC if optimized. We found that systemic IL-2 induced the expression of CXCR3 on circulating mononuclear cells but impaired the CXCR3 ligand chemotactic gradient from plasma to tumor by increasing circulating CXCR3 ligand levels in a murine model of RCC. Moreover, the antitumor effect of systemic IL-2 was CXCR3-dependent, as IL-2 failed to inhibit tumor growth and angiogenesis in CXCR3−/− mice. We hypothesized that the immunotherapeutic effect of the CXCR3/CXCR3 ligand biological axis could be optimized by first priming with systemic IL-2 to induce CXCR3 expression on circulating mononuclear cells followed by enhancing the intratumor CXCR3 ligand levels to establish optimal CXCR3-dependent chemotactic gradient. We found that combined systemic IL-2 with an intratumor CXCR3 ligand (CXCL9) lead to significantly greater reduction in tumor growth and angiogenesis, increased tumor necrosis, and increased intratumor infiltration of CXCR3+ mononuclear cells, as compared with either IL-2 or CXCL9 alone. The enhanced antitumor effect of the combined strategy was associated with a more optimized CXCR3-dependent chemotactic gradient and increased tumor-specific immune response. These data suggest that the combined strategy of systemic IL-2 with intratumor CXCR3 ligand is more efficacious than either strategy alone for reducing tumor-associated angiogenesis and augmenting tumor-associated immunity, the concept of immunoangiostasis.
Protein Vaccines Induce Uncommitted IL-2-Secreting Human and Mouse CD4 T Cells, Whereas Infections Induce More IFN-γ-Secreting Cells
Authors: Divekar Anagha A. , Zaiss Dietmar M. W. , Lee F. Eun-Hyung , Liu Dacheng , Topham David J. , Sijts Alice J. A. M. , Mosmann Tim R. 
Published: April 2014

Abstract
Mouse and human CD4 T cells primed during an immune response may differentiate into effector phenotypes such as Th1 (secreting IFN-γ) or Th2 (secreting IL-4) that mediate effective immunity against different classes of pathogen. However, primed CD4 T cells can also remain uncommitted, secreting IL-2 and chemokines, but not IFN-γ or IL-4. We now show that human CD4 T cells primed by protein vaccines mostly secreted IL-2, but not IFN-γ, whereas in the same individuals most CD4 T cells initially primed by infection with live pathogens secreted IFN-γ. We further demonstrate that many tetanus-specific IL-2+IFN-γ− cells are uncommitted and that a single IL-2+IFN-γ− cell can differentiate into Th1 or Th2 phenotypes following in vitro stimulation under appropriate polarizing conditions. In contrast, influenza-specific IL-2+IFN-γ− CD4 cells maintained a Th1-like phenotype even under Th2-polarizing conditions. Similarly, adoptively transferred OTII transgenic mouse T cells secreted mainly IL-2 after priming with OVA in alum, but were biased toward IFN-γ secretion when primed with the same OVA peptide presented as a pathogen Ag during live infection. Thus, protein subunit vaccines may prime a unique subset of differentiated, but uncommitted CD4 T cells that lack some of the functional properties of committed effectors induced by infection. This has implications for the design of more effective vaccines against pathogens requiring strong CD4 effector T cell responses.
Enhanced FTY720-Mediated Lymphocyte Homing Requires Gαi Signaling and Depends on β2 and β7 Integrin
Authors: Pabst Oliver , Herbrand Heike , Willenzon Stefanie , Worbs Tim , Schippers Angela , Müller Werner , Bernhardt Günter , Förster Reinhold 
Published: April 2014

Abstract
The immunomodulatory drug FTY720 interferes with sphingosine-1-phosphate (S1P) receptor signaling leading to lymphocyte retention in secondary lymphoid organs and consequently to profound lymphopenia in the peripheral blood. The molecular mechanisms transduced by S1P receptors upon being triggered by its native ligand, S1P, or by FTY720, are largely unknown. In this study we analyze the role of β2 and β7 integrin and their ligands ICAM-1, VCAM-1, and MadCAM-1 on lymphocyte homing in the presence of FTY720. We demonstrate that this drug facilitates homing of lymphocytes single-deficient of either β2 or β7 integrin but not of β2-deficient lymphocytes, which in addition were blocked by anti-β7 integrin Abs. Enhanced lymphocyte homing is preceded by increased adherence of integrin-deficient as well as wild-type lymphocytes to high endothelial venules (HEV) in FTY720-treated animals. Elevated adherence to HEV requires intact lymphocyte Gαi signaling that cannot be stably imprinted on lymphocytes even after prolonged exposure to FTY720. Thus, FTY720 influences lymphocyte homeostasis not only by suppressing lymphocyte egress from lymph nodes but also by facilitating lymphocyte homing across HEV in an integrin-dependent fashion.
Splenic Dendritic Cells Induced by Oral Antigen Administration Are Important for the Transfer of Oral Tolerance in an Experimental Model of Asthma
Authors: Nagatani Katsuya , Dohi Makoto , To Yasuo , Tanaka Ryoichi , Okunishi Katsuhide , Nakagome Kazuyuki , Sagawa Kayo , Tanno Yudo , Komagata Yoshinori , Yamamoto Kazuhiko 
Published: April 2014

AbstractPeripheral tolerance can be induced after the feeding of Ag, which is referred to as oral tolerance. We demonstrated in this study that the oral administration of OVA induced tolerance in an experimental model of asthma in mice, and investigated which cells function as the regulatory cells in the transfer of this oral tolerance. In OVA-fed mice, the percentage of eosinophils in bronchoalveolar lavage fluid, serum IgE levels, airway hyperresponsiveness, and mRNA levels of IL-13 and eotaxin were significantly lower than found in nonfed mice. Histological examination of lung tissue showed a suppression of the accumulation of inflammatory cells in the peribronchial area of OVA-fed mice. Feeding after the first immunization or between the first and the second immunization suppressed these findings, whereas feeding just before the airway Ag challenge did not. The suppression of disease in OVA-fed mice was successfully transferred by injection of whole spleen cells of OVA-fed mice. When CD11c+ dendritic cells (DCs) were removed from splenocytes, this transfer of suppression was completely abolished. The injection of splenic DCs purified from OVA-fed mice alone transferred the suppression, whereas the injection of splenic DCs from naive mice that were cocultured with OVA in vitro did not. These data suggest that not only CD4+ T cells, but also CD11c+ DCs induced by Ag feeding are important for the active transfer of oral tolerance in this murine experimental model of asthma.
IL-21 Down-Regulates NKG2D/DAP10 Expression on Human NK and CD8+ T Cells
Authors: Burgess Steven J. , Marusina Alina I. , Pathmanathan Ishani , Borrego Francisco , Coligan John E. 
Published: April 2014

Abstract
IL-21 is a recently described cytokine, produced by activated Th cells, that shares significant homology with members of the IL-2 family of cytokines. IL-21 mediates its biological effects via the IL-21R in conjunction with the common receptor γ-chain that is also shared by members of the IL-2 family. We report that culture of human primary NK and CD8+ T cells with IL-21 in combination with IL-2 results in significant reduction of the cell surface expression of NKG2D, compared with that in cells treated with IL-2 alone. The reduced expression of NKG2D after IL-21 culture had functional consequences for NK cell function, as assessed by NKG2D-mediated redirected lysis assays and degranulation assays, compared with NK cells treated with IL-2 alone. IL-21-mediated NKG2D down-regulation in human NK cells correlated with a marked reduction of DNAX-activating protein of 10 kDa (DAP10) transcription in cells treated with IL-2 in combination with IL-21 compared with cells stimulated with only IL-2. This was attributed to a dramatic reduction in DAP10 promoter activity, as assessed by a DAP10 luciferase reporter construct. In contrast to NKG2D expression, IL-21 was able to induce the expression of the NK activation receptors NKp30 and 2B4 as well as the costimulatory receptor CD28 on CD8+ T cells. These data indicate that IL-21 is able to channel NK and CD8+ T cell function by altering the expression pattern of activation/costimulatory receptors.
CD8 T Cells, Like CD4 T Cells, Are Triggered by Multivalent Engagement of TCRs by MHC-Peptide Ligands but Not by Monovalent Engagement
Authors: Stone Jennifer D. , Stern Lawrence J. 
Published: April 2014

Abstract
T cell activation is initiated by recognition of antigenic peptide presented in complex with MHC molecules on the surface of APCs. The mechanism by which this recognition occurs is still unclear, and many models exist in the literature. CD4 T cells have been shown to respond to soluble oligomers of activating class II MHC-peptide complexes, but not to soluble monomers. In determining the reactivity of CD8 T cells to soluble activating class I MHC-peptide complexes, a complicating phenomenon had been observed whereby peptide from soluble complexes was loaded onto cell surface MHCs on the T cells and re-presented to other T cells, clouding the true valency requirement for activation. This study uses soluble allogeneic class I MHC-peptide monomers and oligomers to stimulate murine CD8 T cells without the possible complication of peptide re-presentation. The results show that MHC class I monomers bind to, but do not activate, CD8 T cells whether the cells are in solution or adhered to a surface. Monomeric MHC class I binding can antagonize the stimulation triggered by soluble oligomers, a phenomenon also observed for CD4 T cells. Dimeric engagement is necessary and sufficient to stimulate downstream activation processes including TCR down-regulation, Zap70 phosphorylation, and CD25 and CD69 up-regulation, even in T cells that do not express the MHC coreceptor CD8. Thus, the valency dependence of the response of CD8 T cells to soluble MHC-peptide reagents is the same as previously observed for CD4 T cells.
Expansion of Functionally Immature Transitional B Cells Is Associated with Human-Immunodeficient States Characterized by Impaired Humoral Immunity
Authors: Cuss Amanda K. , Avery Danielle T. , Cannons Jennifer L. , Yu Li Jun , Nichols Kim E. , Shaw Peter J. , Tangye Stuart G. 
Published: April 2014

AbstractX-linked lymphoproliferative disease (XLP) is a severe immunodeficiency associated with a marked reduction in circulating memory B cells. Our investigation of the B cell compartment of XLP patients revealed an increase in the frequency of a population of B cells distinct from those previously defined. This population displayed increased expression of CD10, CD24, and CD38, indicating that it could consist of circulating immature/transitional B cells. Supporting this possibility, CD10+CD24highCD38high B cells displayed other immature characteristics, including unmutated Ig V genes and elevated levels of surface IgM; they also lacked expression of Bcl-2 and a panel of activation molecules. The capacity of CD24highCD38high B cells to proliferate, secrete Ig, and migrate in vitro was greatly reduced compared with mature B cell populations. Moreover, CD24highCD38high B cells were increased in the peripheral blood of neonates, patients with common variable immunodeficiency, and patients recovering from hemopoietic stem cell transplant. Thus, an expansion of functionally immature B cells may contribute to the humoral immunodeficient state that is characteristic of neonates, as well as patients with XLP or common variable immunodeficiency, and those recovering from a stem cell transplant. Further investigation of transitional B cells will improve our understanding of human B cell development and how alterations to this process may precipitate immunodeficiency or autoimmunity.
CD27 Dissects Mature NK Cells into Two Subsets with Distinct Responsiveness and Migratory Capacity
Authors: Hayakawa Yoshihiro , Smyth Mark J. 
Published: April 2014

AbstractLineage differentiation and the formation of heterogeneous mature subsets are crucial for immune cells to maintain a breadth of responsiveness to pathogens while controlling reactivity to self. In this study, we report that CD27 is a key marker of the NK cell lineage, dissecting the mature Mac-1high NK cell pool into two functionally distinct subsets. The CD27low NK cell subset possesses a higher threshold to stimulation and appears to be tightly regulated by the expression of NK cell inhibitory receptors. Comparatively, the CD27high NK cell subset displays a greater effector function, exhibits a distinct tissue distribution and responsiveness to chemokines, and interacts productively with dendritic cells. Importantly, we have verified that CD27high and CD27low subsets with distinct cell surface phenotypes also exist in human peripheral blood. These findings clearly reclassify mature NK cells into two distinct subsets and begin to discern their specific role in immune responses.
Therapeutic Vaccination of Active Arthritis with a Glycosylated Collagen Type II Peptide in Complex with MHC Class II Molecules
Authors: Dzhambazov Balik , Nandakumar Kutty Selva , Kihlberg Jan , Fugger Lars , Holmdahl Rikard , Vestberg Mikael 
Published: April 2014

Abstract
In both collagen-induced arthritis (CIA) and rheumatoid arthritis, T cells recognize a galactosylated peptide from type II collagen (CII). In this study, we demonstrate that the CII259–273 peptide, galactosylated at lysine 264, in complex with Aq molecules prevented development of CIA in mice and ameliorated chronic relapsing disease. In contrast, nonglycosylated CII259–273/Aq complexes had no such effect. CIA dependent on other MHC class II molecules (Ar/Er) was also down-regulated, indicating a bystander vaccination effect. T cells could transfer the amelioration of CIA, showing that the protection is an active process. Thus, a complex between MHC class II molecules and a posttranslationally modified peptide offers a new possibility for treatment of chronically active autoimmune inflammation such as rheumatoid arthritis.
Pregnancy-Associated Exosomes and Their Modulation of T Cell Signaling
Authors: Taylor Douglas D. , Akyol Sibel , Gercel-Taylor Cicek 
Published: April 2014

AbstractExosome release by viable cells is a feature of activated cell types, including tumors, fetal cells, and cells of the immune system. Exosomes critically regulate immune activation, by mediating activation-induced cell death. Fetal cells may mimic these events to selectively delete reactive lymphocytes. In this study the presence and composition of placenta-derived exosomes are demonstrated in the maternal circulation along with their consequences on T cell activation markers. For all pregnant patients, exosomes were isolated from sera obtained between 28 and 30 wk gestation. For pregnant women, subsequently delivering at term, circulating levels of placental exosomes were 1.8 times greater than those delivering preterm (p &lt; 0.0001). Exosomes isolated from pregnancies subsequently delivering at term expressed significantly higher levels of biologically active components, including Fas ligand (FasL) and HLA-DR, than those from pregnancies delivering preterm. Standardizing for protein concentrations, exosomes from term-delivering pregnancies exhibited greater suppression of CD3-ζ and JAK3 than those delivering preterm. The suppression of CD3-ζ and JAK3 correlated with exosome expression levels of FasL (r2 = 0.92 and r2 = 0.938, respectively). Fractionation of exosomes from term-delivering pregnancies by continuously eluting electrophoresis indicated that intact 42kD FasL and an unidentified 24-kDa protein were associated with CD3-ζ suppression. Our results demonstrated that exosomes from pregnancies ultimately delivering at term are present at significantly greater concentrations than those from pregnancies delivering preterm; however, exosomes from term-delivering pregnancies also exhibit significantly greater suppression of CD3-ζ and JAK3.
Human αβ and γδ Thymocyte Development: TCR Gene Rearrangements, Intracellular TCRβ Expression, and γδ Developmental Potential—Differences between Men and Mice
Authors: Joachims Michelle L. , Chain Jennifer L. , Hooker Scott W. , Knott-Craig Christopher J. , Thompson Linda F. 
Published: April 2014

AbstractTo evaluate the role of the TCR in the αβ/γδ lineage choice during human thymocyte development, molecular analyses of the TCRβ locus in γδ cells and the TCRγ and δ loci in αβ cells were undertaken. TCRβ variable gene segments remained largely in germline configuration in γδ cells, indicating that commitment to the γδ lineage occurred before complete TCRβ rearrangements in most cases. The few TCRβ rearrangements detected were primarily out-of-frame, suggesting that productive TCRβ rearrangements diverted cells away from the γδ lineage. In contrast, in αβ cells, the TCRγ locus was almost completely rearranged with a random productivity profile; the TCRδ locus contained primarily nonproductive rearrangements. Productive γ rearrangements were, however, depleted compared with preselected cells. Productive TCRγ and δ rearrangements rarely occurred in the same cell, suggesting that αβ cells developed from cells unable to produce a functional γδ TCR. Intracellular TCRβ expression correlated with the up-regulation of CD4 and concomitant down-regulation of CD34, and plateaued at the early double positive stage. Surprisingly, however, some early double positive thymocytes retained γδ potential in culture. We present a model for human thymopoiesis which includes γδ development as a default pathway, an instructional role for the TCR in the αβ/γδ lineage choice, and a prolonged developmental window for β selection and γδ lineage commitment. Aspects that differ from the mouse are the status of TCR gene rearrangements at the nonexpressed loci, the timing of β selection, and maintenance of γδ potential through the early double positive stage of development.
Responsiveness of Naive CD4 T Cells to Polarizing Cytokine Determines the Ratio of Th1 and Th2 Cell Differentiation
Authors: Mikhalkevich Natallia , Becknell Brian , Caligiuri Michael A. , Bates Michael D. , Harvey Richard , Zheng Wei-ping 
Published: April 2014

AbstractThe intrinsic features of naive CD4 T cells that affect their ability to respond to polarizing signals for Th cell differentiation are not well understood. In this study, we show that naive CD4 T cells from mice transgenic for the Hlx gene expressed lower levels of IL-4Rα. The down-regulation of IL-4Rα diminished IL-4 signaling and the Th2 response and enhanced the Th1 response under suboptimal polarizing conditions. In nontransgenic CD4 T cells, blocking IL-4Rα with Abs had the same effect in an Ab dose-dependent manner. Conversely, Hlx haploinsufficiency caused higher expression of IL-4Rα to favor Th2 cell differentiation. Thus, the IL-4Rα level on naive CD4 T cells is genetically controlled by Hlx and determines the ratio of Th1 and Th2 cell differentiation.
TLR Agonists Abrogate Costimulation Blockade-Induced Prolongation of Skin Allografts
Authors: Thornley Thomas B. , Brehm Michael A. , Markees Thomas G. , Shultz Leonard D. , Mordes John P. , Welsh Raymond M. , Rossini Aldo A. , Greiner Dale L. 
Published: April 2014

AbstractCostimulation blockade protocols are effective in prolonging allograft survival in animal models and are entering clinical trials, but how environmental perturbants affect graft survival remains largely unstudied. We used a costimulation blockade protocol consisting of a donor-specific transfusion and anti-CD154 mAb to address this question. We observed that lymphocytic choriomeningitis virus infection at the time of donor-specific transfusion and anti-CD154 mAb shortens allograft survival. Lymphocytic choriomeningitis virus 1) activates innate immunity, 2) induces allo-cross-reactive T cells, and 3) generates virus-specific responses, all of which may adversely affect allograft survival. To investigate the role of innate immunity, mice given costimulation blockade and skin allografts were coinjected with TLR2 (Pam3Cys), TLR3 (polyinosinic:polycytidylic acid), TLR4 (LPS), or TLR9 (CpG) agonists. Costimulation blockade prolonged skin allograft survival that was shortened after coinjection by TLR agonists. To investigate underlying mechanisms, we used “synchimeric” mice which circulate trace populations of anti-H2b transgenic alloreactive CD8+ T cells. In synchimeric mice treated with costimulation blockade, coadministration of all four TLR agonists prevented deletion of alloreactive CD8+ T cells and shortened skin allograft survival. These alloreactive CD8+ T cells 1) expressed the proliferation marker Ki-67, 2) up-regulated CD44, and 3) failed to undergo apoptosis. B6.TNFR2−/− and B6.IL-12R−/− mice treated with costimulation blockade plus LPS also exhibited short skin allograft survival whereas similarly treated B6.CD8α−/− and TLR4−/− mice exhibited prolonged allograft survival. We conclude that TLR signaling abrogates the effects of costimulation blockade by preventing alloreactive CD8+ T cell apoptosis through a mechanism not dependent on TNFR2 or IL-12R signaling.
Tec Kinases Itk and Rlk Are Required for CD8+ T Cell Responses to Virus Infection Independent of Their Role in CD4+ T Cell Help
Authors: Atherly Luana O. , Brehm Michael A. , Welsh Raymond M. , Berg Leslie J. 
Published: April 2014

Abstract
Itk and Rlk are members of the Tec kinase family of nonreceptor protein tyrosine kinases that are expressed in T cells, NK cells, and mast cells. These proteins are involved in the regulation of signaling processes downstream of the TCR in CD4+ T cells, particularly in the phosphorylation of phospholipase C-γ1 after TCR activation; furthermore, both Itk and Rlk are important in CD4+ T cell development, differentiation, function, and homeostasis. However, few studies have addressed the roles of these kinases in CD8+ T cell signaling and function. Using Itk−/− and Itk−/−Rlk−/− mice, we examined the roles of these Tec family kinases in CD8+ T cells, both in vitro and in vivo. These studies demonstrate that the loss of Itk and Rlk impairs TCR-dependent signaling, causing defects in phospholipase C-γ1, p38, and ERK activation as well as defects in calcium flux and cytokine production in vitro and expansion and effector cytokine production by CD8+ T cells in response to viral infection. These defects cannot be rescued by providing virus-specific CD4+ T cell help, thereby substantiating the important role of Tec kinases in CD8+ T cell signaling.