bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dendritic Cells Prime In Vivo Alloreactive CD4 T Lymphocytes Toward Type 2 Cytokine- and TGF-β-Producing Cells in the Absence of CD8 T Cell Activation
Authors: Foucras Gilles , Coudert Jérôme D. , Coureau Christiane , Guéry Jean-Charles 
Published: April 2014

AbstractThe mechanisms that influence the polarization of CD4 T cells specific for allogeneic MHC class II molecules in vivo are still poorly understood. We have examined the pathway of alloreactive CD4 T cell differentiation in a situation in which only CD4 T cells could be activated in vivo. In this report we show that priming of adult mice with allogeneic APC, in the absence of MHC class I-T cell interactions, induces a strong expansion of type 2 cytokine-producing allohelper T cells. These alloantigen-specific CD4 T cells directly recognize native allogeneic MHC class II molecules on APC and secrete, in addition to the prototypic Th2 cytokines IL-4, IL-5, and IL-10, large amounts of TGF-β. The default Th2-phenotype acquisition is not genetically controlled and occurred both in BALB/c and C57BL/6 mice. CD8 T cells are the principal cell type that controls CD4 T cell differentiation in vivo. Furthermore, we demonstrate that strong Th2 priming can be induced not only with allogeneic splenocytes but also with a low number of bone marrow-derived dendritic cells. Finally, using a passive transfer system, we provide direct evidence that CD8 T cell expansion in situ promotes alloreactive Th1 cell development principally by preventing their default development to the Th2 pathway in a mechanism that is largely IFN-γ independent. Therefore, this work demonstrates that type 2 cytokine production represents a dominant pathway of alloreactive CD4 T cell differentiation in adult mice, a phenomenon that was initially thought to occur only during the neonatal period.
Mouse Inducible Costimulatory Molecule (ICOS) Expression Is Enhanced by CD28 Costimulation and Regulates Differentiation of CD4+ T Cells
Authors: McAdam Alexander J. , Chang Tammy T. , Lumelsky Anna E. , Greenfield Edward A. , Boussiotis Vassiliki A. , Duke-Cohan Jonathan S. , Chernova Tatyana , Malenkovich Nelly , Jabs Claudia , Kuchroo Vijay K. , Ling Vincent , Collins Mary , Sharpe Arlene H. , Freeman Gordon J. 
Published: April 2014

Abstract
The inducible costimulatory (ICOS) molecule is expressed by activated T cells and has homology to CD28 and CD152. ICOS binds B7h, a molecule expressed by APC with homology to CD80 and CD86. To investigate regulation of ICOS expression and its role in Th responses we developed anti-mouse ICOS mAbs and ICOS-Ig fusion protein. Little ICOS is expressed by freshly isolated mouse T cells, but ICOS is rapidly up-regulated on most CD4+ and CD8+ T cells following stimulation of the TCR. Strikingly, ICOS up-regulation is significantly reduced in the absence of CD80 and CD86 and can be restored by CD28 stimulation, suggesting that CD28-CD80/CD86 interactions may optimize ICOS expression. Interestingly, TCR-transgenic T cells differentiated into Th2 expressed significantly more ICOS than cells differentiated into Th1. We used two methods to investigate the role of ICOS in activation of CD4+ T cells. First, CD4+ cells were stimulated with beads coated with anti-CD3 and either B7h-Ig fusion protein or control Ig fusion protein. ICOS stimulation enhanced proliferation of CD4+ cells and production of IFN-γ, IL-4, and IL-10, but not IL-2. Second, TCR-transgenic CD4+ T cells were stimulated with peptide and APC in the presence of ICOS-Ig or control Ig. When the ICOS:B7h interaction was blocked by ICOS-Ig, CD4+ T cells produced more IFN-γ and less IL-4 and IL-10 than CD4+ cells differentiated with control Ig. These results demonstrate that ICOS stimulation is important in T cell activation and that ICOS may have a particularly important role in development of Th2 cells.
Blockade of Costimulation Through B7/CD28 Inhibits Experimental Autoimmune Uveoretinitis, But Does Not Induce Long-Term Tolerance
Authors: Silver Phyllis B. , Hathcock Karen S. , Chan Chi-Chao , Wiggert Barbara , Caspi Rachel R. 
Published: April 2014

Abstract
It has been reported that costimulation blockade can result in T cell anergy. We investigated the effects of blocking costimulatory molecules in vivo on the development of experimental autoimmune uveoretinitis (EAU), a model for autoimmune uveitis in humans that is induced in mice by immunization with the retinal Ag interphotoreceptor retinoid binding protein. B10.A mice immunized with a uveitogenic regimen of interphotoreceptor retinoid-binding protein were treated with Abs to B7.1 and B7.2 for 2 wk. Evaluation of EAU and immunological responses 1 wk later showed that disease had been abrogated, and cellular responses were suppressed. To determine whether the costimulation blockade resulted in tolerance, adult-thymectomized mice immunized for uveitis and treated with anti-B7 or anti-CD28 were rechallenged for uveitis induction 5 wk after the initial immunization. Although confirmed to be disease free after the initial immunization, both anti-B7- and anti-CD28-treated mice developed severe EAU and elevated cellular responses after the rechallenge, equivalent to those of control mice. We conclude that in this model costimulatory blockade in vivo prevents the development of autoimmune disease, but does not result in long-term tolerance. The data are compatible with the interpretation that B7/CD28 blockade prevents generation of effector, but not of memory, T cells.
Allergen-Induced Airway Hyperreactivity Is Diminished in CD81-Deficient Mice
Authors: Deng Jun , Yeung V. Pete , Tsitoura Daphne , DeKruyff Rosemarie H. , Umetsu Dale T. , Levy Shoshana 
Published: April 2014

Abstract
We demonstrated previously that CD81−/− mice have an impaired Th2 response. To determine whether this impairment affected allergen-induced airway hyperreactivity (AHR), CD81−/− BALB/c mice and CD81+/+ littermates were sensitized i.p. and challenged intranasally with OVA. Although wild type developed severe AHR, CD81−/− mice showed normal airway reactivity and reduced airway inflammation. Nevertheless, OVA-specific T cell proliferation was similar in both groups of mice. Analysis of cytokines secreted by the responding CD81−/− T cells, particularly those derived from peribronchial draining lymph nodes, revealed a dramatic reduction in IL-4, IL-5, and IL-13 synthesis. The decrease in cytokine production was not due to an intrinsic T cell deficiency because naive CD81−/− T cells responded to polyclonal Th1 and Th2 stimulation with normal proliferation and cytokine production. Moreover, there was an increase in T cells and a decrease in B cells in peribronchial lymph nodes and in spleens of immunized CD81−/− mice compared with wild-type animals. Interestingly, OVA-specific Ig levels, including IgE, were similar in CD81−/− and CD81+/+ mice. Thus, CD81 plays a role in the development of AHR not by influencing Ag-specific IgE production but by regulating local cytokine production.
Vaginal Mucosa Serves as an Inductive Site for Tolerance
Authors: Black C. Allen , Rohan Lisa C. , Cost Marilyn , Watkins Simon C. , Draviam Romesh , Alber Sean , Edwards Robert P. 
Published: April 2014

Abstract
These data demonstrate that tolerance can be induced by vaginal Ag exposure. In these experiments, mice were given vaginal agarose gel suppositories containing either 5 mg OVA or saline for 6 h. Mice were given suppositories either during the estrous (estrogen dominant) or diestrous (progesterone dominant) stage of the estrous cycle. Mice were restrained during the inoculation period to prevent orovaginal transmission of the Ag. After 1 wk, mice were immunized s.c. with OVA in CFA. After 3 wk, mice were tested for delayed-type hypersensitivity responses by measuring footpad swelling and measuring in vitro proliferation of lymphocytes to Ag. Using ELISA, the magnitude of the serum Ab response was also measured. In some mice, FITC conjugated to OVA was used to track the dissemination of the protein into the systemic tissues. The magnitude of footpad swelling was significantly reduced in mice receiving OVA-containing suppositories during estrus compared with mice receiving saline suppositories. Concomitant decreases in the Ag-specific proliferative response were also observed in lymph node lymphocytes and splenocytes. Conversely, mice inoculated during diestrus did not show a decreased response to Ag by either footpad response or in vitro proliferation. Serum Ab titers in the estrus-inoculated mice did not decrease significantly. These data demonstrate that the reproductive tract can be an inductive site for mucosally induced tolerance. However, unlike other mucosal sites such as the lung and gastrointestinal tract, reproductive tract tolerance induction is hormonally regulated.
TNFR-Associated Factor Family Protein Expression in Normal Tissues and Lymphoid Malignancies
Authors: Zapata Juan M. , Krajewska Maryla , Krajewski Stanislaw , Kitada Shinichi , Welsh Kate , Monks Anne , McCloskey Natalie , Gordon John , Kipps Thomas J. , Gascoyne Randy D. , Shabaik Ahmed , Reed John C. 
Published: April 2014

Abstract
TNFR-associated factors (TRAFs) constitute a family of adapter proteins that associate with particular TNF family receptors. Humans and mice contain six TRAF genes, but little is known about their in vivo expression at the single cell level. The in vivo locations of TRAF1, TRAF2, TRAF5, and TRAF6 were determined in human and mouse tissues by immunohistochemistry. Striking diversity was observed in the patterns of immunostaining obtained for each TRAF family protein, suggesting their expression is independently regulated in a cell type-specific manner. Dynamic regulation of TRAFs was observed in cultured PBLs, where anti-CD3 Abs, mitogenic lectins, and ILs induced marked increases in the steady-state levels of TRAF1, TRAF2, TRAF5, and TRAF6. TRAF1 was also highly inducible by CD40 ligand in cultured germinal center B cells, whereas TRAF2, TRAF3, TRAF5, and TRAF6 were relatively unchanged. Analysis of 83 established human tumor cell lines by semiquantitative immunoblotting methods revealed tendencies of certain cancer types to express particular TRAFs. For example, expression of TRAF1 was highly restricted, with B cell lymphomas consistently expressing this TRAF family member. Consistent with results from tumor cell lines, immunohistochemical analysis of 232 non-Hodgkin lymphomas revealed TRAF1 overexpression in 112 (48%) cases. TRAF1 protein levels were also elevated in circulating B cell chronic lymphocytic leukemia specimens (n = 49) compared with normal peripheral blood B cells (p = 0.01), as determined by immunoblotting. These findings contribute to an improved understanding of the cell-specific roles of TRAFs in normal tissues and provide evidence of altered TRAF1 expression in lymphoid malignancies.
Functional Uncoupling of the Janus Kinase 3-Stat5 Pathway in Malignant Growth of Human T Cell Leukemia Virus Type 1-Transformed Human T Cells
Authors: Kirken Robert A. , Erwin Rebecca A. , Wang Lihua , Wang Yuling , Rui Hallgeir , Farrar William L. 
Published: April 2014

Abstract
Human T cell leukemia virus type 1 (HTLV-1) transforms cytokine-dependent T lymphocytes and causes adult T cell leukemia. Janus tyrosine kinase (Jak)3 and transcription factors Stat5a and Stat5b are essential for the proliferation of normal T cells and are constitutively hyperactivated in both HTLV-1-transformed human T cell lines and lymphocytes isolated from HTLV-1-infected patients; therefore, a critical role for the Jak3-Stat5 pathway in the progression of this disease has been postulated. We recently reported that tyrphostin AG-490 selectively blocked IL-2 activation of Jak3/Stat5 and growth of murine T cell lines. Here we demonstrate that disruption of Jak3/Stat5a/b signaling with AG-490 (50 μM) blocked the proliferation of primary human T lymphocytes, but paradoxically failed to inhibit the proliferation of HTLV-1-transformed human T cell lines, HuT-102 and MT-2. Structural homologues of AG-490 also inhibited the proliferation of primary human T cells, but not HTLV-1-infected cells. Disruption of constitutive Jak3/Stat5 activation by AG-490 was demonstrated by inhibition of 1) tyrosine phosphorylation of Jak3, Stat5a (Tyr694), and Stat5b (Tyr699); 2) serine phosphorylation of Stat5a (Ser726) as determined by a novel phosphospecific Ab; and 3) Stat5a/b DNA binding to the Stat5-responsive β-casein promoter. In contrast, AG-490 had no effect on DNA binding by p50/p65 components of NF-κB, a transcription factor activated by the HTLV-1-encoded phosphoprotein, Tax. Collectively, these data suggest that the Jak3-Stat5 pathway in HTLV-1-transformed T cells has become functionally redundant for proliferation. Reversal of this functional uncoupling may be required before Jak3/Stat5 inhibitors will be useful in the treatment of this malignancy.
The Inference of Antigen Selection on Ig Genes
Authors: Lossos Izidore S. , Tibshirani Robert , Narasimhan Balasubramanian , Levy Ronald 
Published: April 2014

Abstract
Analysis of somatic mutations in V regions of Ig genes is important for understanding various biological processes. It is customary to estimate Ag selection on Ig genes by assessment of replacement (R) as opposed to silent (S) mutations in the complementary-determining regions and S as opposed to R mutations in the framework regions. In the past such an evaluation was performed using a binomial distribution model equation, which is inappropriate for Ig genes in which mutations have four different distribution possibilities (R and S mutations in the complementary-determining region and/or framework regions of the gene). In the present work, we propose a multinomial distribution model for assessment of Ag selection. Side-by-side application of multinomial and binomial models on 86 previously established Ig sequences disclosed 8 discrepancies, leading to opposite statistical conclusions about Ag selection. We suggest the use of the multinomial model for all future analysis of Ag selection.
Enhanced Murine Macrophage TNF Receptor Shedding by Cytosine-Guanine Sequences in Oligodeoxynucleotides
Authors: Jin Long , Raymond Daniel P. , Crabtree Traves D. , Pelletier Shawn J. , Houlgrave C. Webster , Pruett Timothy L. , Sawyer Robert G. 
Published: April 2014

AbstractThe immunomodulatory role of unmethylated cytosine-guanine sequences (CpG) in bacterial DNA has been well documented. We have previously demonstrated that murine macrophage-like RAW 264.7 cells respond to CpG DNA with an increase in the proinflammatory cytokine, TNF-α, in both a dose-dependent and time-dependent manner. In addition, CpG DNA stimulates a significant, though delayed, secretion of the anti-inflammatory cytokine IL-10. Because TNF-α and TNFR (TNFRI and II) expression are tightly regulated responses, we hypothesized that CpG containing oligodeoxynucleotide (CpG ODN) would also affect TNFRI and II shedding. Using both murine peritoneal macrophages and RAW 264.7 cells, we demonstrated a significant, time-dependent increase in soluble TNFRI and TNFRII production with CpG ODN stimulation. RAW 264.7 cells treated with CpG ODN had a transient increase in membrane TNFRII expression, but not TNFRI. Both types of TNFR mRNA were also up-regulated by CpG ODN, and addition of the transcriptional inhibitor actinomycin D abrogated the effect of CpG ODN on TNFR mRNA and protein expression. Addition of anti-IL-10 and anti-TNF-α Abs did not change these results. The addition of plate-bound anti-TNF receptor Abs to this system increased the amount of bioactive TNF, implying that these receptors are acting as inhibitors of TNF activity. These results suggest that the de novo, non-IL-10- and non-TNF-α-dependent transcription, translation, and shedding of TNFRs are additional potential counterinflammatory effects of CpG DNA.
The Serpin Secreted byBrugia malayiMicrofilariae, Bm-SPN-2, Elicits Strong, but Short-Lived, Immune Responses in Mice and Humans
Authors: Zang Xingxing , Atmadja Agnes Kurniawan , Gray Paul , Allen Judith E. , Gray Carolyn A. , Lawrence Rachel A. , Yazdanbakhsh Maria , Maizels Rick M. 
Published: April 2014

AbstractUnderstanding the basic immunology of an infectious disease requires insight into the pattern of T cell reactivity and specificity. Although lymphatic filariasis is a major tropical disease, the predominant T cell Ags of filarial species such as Brugia malayi are still undefined. We have now identified a prominent T cell Ag from B. malayi microfilariae (Mf) as Bm-SPN-2, a serpin secreted exclusively by this stage. Mf-infected mice mounted strong, but short-lived, Bm-SPN-2-specific Th1 responses, measured by in vitro production of IFN-γ, but not IL-4 or IL-5, 14 days postinfection. By day 35, responsiveness to Bm-SPN-2 was lost despite enhanced reactivity to whole Mf extract. Single immunization with Mf extract also stimulated typical Th1 reactions to Bm-SPN-2, but IgG1 Ab responses dominated after repeated immunizations. Human patients displayed potent humoral responses to Bm-SPN-2 in both IgG1 and IgG4 subclasses. Thus, 100% (20 of 20) of the microfilaremic (MF+) patients bore IgG4 responses to Bm-SPN-2, while only 30% of endemic normal subjects were similarly positive. Following chemotherapy, Bm-SPN-2-specific Abs disappeared in 12 of 13 MF+ patients, although the majority remained seropositive for whole parasite extract. PBMC from most, but not all, endemic subjects were induced to secrete IFN-γ when stimulated with Bm-SPN-2. These findings demonstrate that Bm-SPN-2 is recognized by both murine and human T and B cells and indicate that their responses are under relatively stringent temporal control. This study also provides the first example of a stage-specific secreted molecule that acts as a major T cell Ag from filarial parasites and is a prime candidate for a serodiagnostic probe.
Inhibition of IL-6 and IL-10 Signaling and Stat Activation by Inflammatory and Stress Pathways
Authors: Ahmed Simi T. , Ivashkiv Lionel B. 
Published: April 2014

AbstractThe development and resolution of an inflammatory process are regulated by a complex interplay among cytokines that have pro- and anti-inflammatory effects. Effective and sustained action of a proinflammatory cytokine depends on synergy with other inflammatory cytokines and antagonism of opposing cytokines that are often highly expressed at inflammatory sites. We analyzed the effects of the inflammatory and stress agents, IL-1, TNF-α, LPS, sorbitol, and H2O2, on signaling by IL-6 and IL-10, pleiotropic cytokines that activate the Jak-Stat signaling pathway and have both pro- and anti-inflammatory actions. IL-1, TNF-α, and LPS blocked the activation of Stat DNA binding and tyrosine phosphorylation by IL-6 and IL-10, but not by IFN-γ, in primary macrophages. Inhibition of Stat activation correlated with inhibition of expression of IL-6-inducible genes. The inhibition was rapid and independent of de novo gene induction and occurred when the expression of suppressor of cytokine synthesis-3 was blocked. Inhibition of IL-6 signaling was mediated by the p38 subfamily of stress-activated protein kinases. Jak1 was inhibited at the level of tyrosine phosphorylation, indicating that inhibition occurred at least in part upstream of Stats in the Jak-Stat pathway. Experiments using Stat3 mutated at serine 727 and using truncated IL-6Rs suggested that the target of inhibition is contained within the membrane-proximal region of the cytoplasmic domain of the gp130 subunit of the IL-6 receptor and is different from the SH2 domain-containing protein-tyrosine phosphatase/suppressor of cytokine synthesis-3 docking site. These results identify a new level at which IL-1 and TNF-α modulate signaling by pleiotropic cytokines such as IL-6 and IL-10 and provide a molecular basis for the previously described antagonism of certain IL-6 actions by IL-1.
The Mitogen-Activated Protein Kinase Extracellular Signal-Regulated Kinase 1/2 Pathway Is Involved in formyl-Methionyl-Leucyl-Phenylalanine-Induced p47phox Phosphorylation in Human Neutrophils
Authors: Dewas Cédric , Fay Michèle , Gougerot-Pocidalo Marie-Anne , El-Benna Jamel 
Published: April 2014

AbstractPhosphorylation of p47 phagocyte oxidase, (p47phox), one of the NADPH oxidase components, is essential for the activation of this enzyme and for superoxide production. p47phox is phosphorylated on multiple serine residues, but the kinases involved in this process in vivo remain to be characterized. We examined the role of extracellular signal-regulated kinase (ERK1/2) and p38 mitogen-activated protein kinase in p47phox phosphorylation. Inhibition of ERK1/2 activation by PD98059, a specific inhibitor of ERK kinase 1/2, inhibited the fMLP-induced phosphorylation of p47phox. However, PD98059 weakly affected PMA-induced p47phox phosphorylation, even though ERK1/2 activation was abrogated. This effect was confirmed using U0126, a second ERK kinase inhibitor. Unlike PD98059 and U0126, the p38 mitogen-activated protein kinase inhibitor SB203580 did not inhibit the phosphorylation of p47phox induced either by fMLP or by PMA. Two-dimensional phosphopeptide mapping analysis showed that, in fMLP-induced p47phox phosphorylation, PD98059 affected the phosphorylation of all the major phosphopeptides, suggesting that ERK1/2 may regulate p47phox phosphorylation either directly or indirectly via other kinases. In PMA-induced p47phox phosphorylation, GF109203X, a protein kinase C inhibitor, strongly inhibits p47phox phosphorylation. However, in fMLP-induced p47phox phosphorylation, PD98059 and GF109203X partially inhibited the phosphorylation of p47phox when tested alone, and exerted additive inhibitory effects on p47phox phosphorylation when tested together. These results show for the first time that the ERK1/2 pathway participates in the phosphorylation of p47phox. Furthermore, they strongly suggest that p47phox is targeted by several kinase cascades in intact neutrophils activated by fMLP and is therefore a converging point for ERK1/2 and protein kinase C.
The CXC Chemokine Receptor 2, CXCR2, Is the Putative Receptor for ELR+ CXC Chemokine-Induced Angiogenic Activity
Authors: Addison Christina L. , Daniel Thomas O. , Burdick Marie D. , Liu Hua , Ehlert Jan E. , Xue Ying Ying , Buechi Linda , Walz Alfred , Richmond Ann , Strieter Robert M. 
Published: April 2014

Abstract
We have previously shown that members of the ELR+ CXC chemokine family, including IL-8; growth-related oncogenes α, β, and γ; granulocyte chemotactic protein 2; and epithelial neutrophil-activating protein-78, can mediate angiogenesis in the absence of preceding inflammation. To date, the receptor on endothelial cells responsible for chemotaxis and neovascularization mediated by these ELR+ CXC chemokines has not been determined. Because all ELR+ CXC chemokines bind to CXC chemokine receptor 2 (CXCR2), we hypothesized that CXCR2 is the putative receptor for ELR+ CXC chemokine-mediated angiogenesis. To test this postulate, we first determined whether cultured human microvascular endothelial cells expressed CXCR2. CXCR2 was detected in human microvascular endothelial cells at the protein level by both Western blot analysis and immunohistochemistry using polyclonal Abs specific for human CXCR2. To determine whether CXCR2 played a functional role in angiogenesis, we determined whether this receptor was involved in endothelial cell chemotaxis. We found that microvascular endothelial cell chemotaxis in response to ELR+ CXC chemokines was inhibited by anti-CXCR2 Abs. In addition, endothelial cell chemotaxis in response to ELR+ CXC chemokines was sensitive to pertussis toxin, suggesting a role for G protein-linked receptor mechanisms in this biological response. The importance of CXCR2 in mediating ELR+ CXC chemokine-induced angiogenesis in vivo was also demonstrated by the lack of angiogenic activity induced by ELR+ CXC chemokines in the presence of neutralizing Abs to CXCR2 in the rat corneal micropocket assay, or in the corneas of CXCR2−/− mice. We thus conclude that CXCR2 is the receptor responsible for ELR+ CXC chemokine-mediated angiogenesis.