bluuebunny/crossref_metadata_2025_split huggingface dataset:
CXCR3 Expression on CD34+ Hemopoietic Progenitors Induced by Granulocyte-Macrophage Colony-Stimulating Factor: II. Signaling Pathways Involved
Authors: Jinquan Tan , Anting Liu , Jacobi Henrik H. , Glue Christian , Jing Chen , Ryder Lars P. , Madsen Hans O. , Svejgaard Arne , Skov Per S. , Malling Hans-Jørgen , Poulsen Lars K. 
Published: April 2014

Abstract
CXCR3, known to have four ligands (IFN-γ inducible protein 10 (γ IP-10), monokine induced by IFN-γ (Mig), I-TAC, and 6Ckine), is predominately expressed on memory/activated T lymphocytes. We recently reported that GM-CSF induces CXCR3 expression on CD34+ hemopoietic progenitors, in which γ IP-10 and Mig induce chemotaxis and adhesion. Here we further report that stimulation with GM-CSF causes phosphorylation of Syk protein kinase, but neither Casitas B-lineage lymphoma (Cbl) nor Cbl-b in CD34+ hemopoietic progenitors can be blocked by anti-CD116 mAb. Specific Syk blocking generated by PNA antisense completely inhibits GM-CSF-induced CXCR3 expression in CD34+ progenitors at both mRNA and protein as well as at functional levels (chemotaxis and adhesion). Cbl and Cbl-b blocking have no such effects. Thus, GM-CSF binds to its receptor CD116, and consequently activates Syk phosphorylation, which leads to induce CXCR3 expression. γ IP-10 and Mig can induce Syk, Cbl, and Cbl-b phosphorylation in CD34+ progenitors by means of CXCR3. γ IP-10 or Mig has induced neither chemotaxis nor adhesion in GM-CSF-stimulated Cbl-b-blocked CD34+ hemopoietic progenitors, whereas SDF-1α induces both chemotaxis and adhesion in these cells. Interestingly, γ IP-10 and Mig can induce chemotaxis and adhesion in GM-CSF-stimulated Syk- or Cbl-blocked CD34+ hemopoietic progenitors. Thus, Cbl-b, but not Syk and Cbl phosphorylation, is essential for γ IP-10- and Mig-induced chemotaxis and adhesion in CD34+ hemopoietic progenitors. This study provides a useful insight into novel signaling transduction pathways of the functions of CXCR3/γ IP-10 and Mig, which may be especially important in the cytokine/chemokine environment for mobilization, homing, and recruitment during proliferation, differentiation, and maturation of hemopoietic progenitor cells.
The Cell Type-Specific Expression of the Murine IL-13 Gene Is Regulated by GATA-3
Authors: Kishikawa Hiroko , Sun Jenny , Choi Andrew , Miaw Shi-Chuen , Ho I-Cheng 
Published: April 2014

Abstract
IL-13, a Th2 cell-specific cytokine, is a major effector molecule mediating several pathological features of allergic asthma. However, the transcriptional regulation of the IL-13 gene remains unclear. Here we demonstrate, by using intracellular cytokine staining, that IL-13 is not always coexpressed with other Th2 cytokines in normal Th cells on a single cell basis. In addition, we identified and cloned a minimal inducible and cell type-specific promoter of the murine IL-13 gene. The cell type specificity of the minimal IL-13 promoter is mediated by a functionally critical GATA-3 site that binds endogenous GATA-3 proteins, whereas the induction by PMA/ionomycin is mediated by distinct cis-acting elements. Furthermore, by expressing GATA-3 in wild-type and c-maf transgenic Th1 cells, we demonstrate that the expression of IL-13 is regulated by a mechanism distinct from that regulating the expression of IL-4, and that the expression of Th1 and Th2 cytokine genes does not have to be mutually exclusive in effector Th cells.
Unique Function for Carboxyl-Terminal Domain of Oct-2 in Ig-Secreting Cells
Authors: Sharif M. Nusrat , Radomska Hanna S. , Miller David M. , Eckhardt Laurel A. 
Published: April 2014

Abstract
The activity of Ig gene promoters and enhancers is regulated by two related transcription factors, Oct-1 (ubiquitous) and Oct-2 (B lineage specific), which bind the octamer motif (ATTTGCAT) present in these elements. As Ig promoter-binding factors, Oct-1 and Oct-2 each work together with a B lymphocyte-specific cofactor OCA-B/OBF-1/Bob-1 that interacts with them through their POU (DNA-binding) domains. Because both can mediate Ig promoter activity in B cells, there has been some question as to whether these two octamer-binding factors serve distinct functions in lymphocytes. We have shown previously that the silencing of B lymphocyte-specific genes in plasmacytoma × T lymphoma hybrids can be prevented by preserving Oct-2 expression. The pronounced effect of this transcription factor on the phenotype of plasmacytoma × T lymphoma hybrids established a critical role for Oct-2 not only in maintaining Ig gene expression, but in maintaining the overall genetic program of Ig-secreting cells. In the present study, we have explored the functional differences between Oct-1 and Oct-2 using chimeric Oct-1/Oct-2 proteins in cell fusion assays. Our results provide further evidence for an essential role for Oct-2 in Ig-secreting cells and identify the C-terminal domain of Oct-2 as responsible for its unique function in these cells.
Identification of a Novel Cytokine, ML-1, and Its Expression in Subjects with Asthma
Authors: Kawaguchi Mio , Onuchic Luiz F. , Li Xiao-Dong , Essayan David M. , Schroeder John , Xiao Hui-Qing , Liu Mark C. , Krishnaswamy Guha , Germino Gregory , Huang Shau-Ku 
Published: April 2014

Abstract
A novel gene, designated ML-1, was identified from a human genomic DNA clone and human T cell cDNA sequences. The second exon of ML-1 gene shares significant sequence identity with the gene encoding IL-17 (IL-17). ML-1 gene expression was up-regulated in activated PBMCs, CD4+ T cells, allergen-specific Th0, Th1, and Th2 clones, activated basophils, and mast cells. Increased expression of the ML-1 gene, but not IL-17, was seen following allergen challenge in four asthmatic subjects, suggesting its role in allergic inflammatory responses. ML-1 from transiently transfected COS-7 cells was able to induce gene expression and protein production for IL-6 and IL-8 (at 10 ng/ml of ML-1: for IL-6, 599.6 ± 19.1 pg/ml; for IL-8, 1724.2 ± 132.9 pg/ml; and at 100 ng/ml of ML-1: for IL-6, 1005.3 ± 55.6 pg/ml; for IL-8, 4371.4 ± 280.5 pg/ml; p &lt; 0.05 for both doses vs baseline) in primary bronchial epithelial (PBE) cells. Furthermore, increased expression of ICAM-1 was found in ML-1-stimulated PBE cells (mean fluorescence intensity (MFI) = 31.42 ± 4.39 vs baseline, MFI = 12.26 ± 1.77, p &lt; 0.05), a functional feature distinct from IL-17 (MFI = 11.07 ± 1.22). This effect was not inhibited by a saturating amount of IL-17. These findings demonstrate that ML-1 is a novel cytokine with a distinct function, and suggest a different receptor for ML-1 on PBE cells.
IL-10 Inhibits Apoptosis of Promyeloid Cells by Activating Insulin Receptor Substrate-2 and Phosphatidylinositol 3′-Kinase
Authors: Zhou Jian-Hua , Broussard Suzanne R. , Strle Klemen , Freund Gregory G. , Johnson Rodney W. , Dantzer Robert , Kelley Keith W. 
Published: April 2014

AbstractIL-10 is well known to be a potent inhibitor of the synthesis of proinflammatory cytokines, but noninflammatory hemopoietic cells also express IL-10Rs. Here we show that IL-10 directly affects progenitor myeloid cells by protecting them from death following the removal of growth factors. Murine factor-dependent cell progenitors cultured in the absence of growth factors were 43 ± 1% apoptotic after 12 h. Addition of IL-10 at a concentration as low as 100 pg/ml significantly reduced the apoptotic population to 32 ± 3%. At 10 ng/ml, IL-10 caused a 4-fold reduction in the apoptotic population (11 ± 1%). The anti-apoptotic activity of IL-10 was significantly inhibited with a neutralizing IL-10R Ab. Factor-dependent cell progenitor promyeloid cells expressed functional IL-10Rs, as assessed by precipitation of a 110-kDa protein with an Ab to the IL-10R and by the ability of IL-10 to activate Jak1 and Tyk2 and to phosphorylate tyrosine 705 on Stat-3. IL-10 increased tyrosyl phosphorylation of insulin receptor substrate-2 and stimulated the enzymatic activity of both phosphatidylinositol 3′-kinase and Akt. The anti-apoptotic activity of IL-10 was blocked by inhibition of phosphatidylinositol 3′-kinase. Wortmannin and LY294002 also totally inhibited activation of extracellular signal-related kinase (ERK)1/2 by IL-10. Direct inhibition of ERK1/2 with the mitogen-activated protein kinase/ERK kinase inhibitor PD98059 partially, but significantly, impaired the anti-apoptotic activity of IL-10. These data establish that activation of the IL-10R promotes survival of progenitor myeloid cells. This survival-promoting activity is totally due to IL-10 stimulating the insulin receptor substrate-2/PI 3-kinase/Akt pathway, which increases the anti-apoptotic activity of ERK1/2.
A Region of Tapasin That Affects Ld Binding and Assembly
Authors: Turnquist Hēth R. , Vargas Shanna E. , Reber Adrian J. , McIlhaney Mary M. , Li Suling , Wang Ping , Sanderson Sam D. , Gubler Brigitte , van Endert Peter , Solheim Joyce C. 
Published: April 2014

Abstract
Tapasin has been shown to stabilize TAP and to link TAP to the MHC class I H chain. Evidence also has been presented that tapasin influences the loading of peptides onto MHC class I. To explore the relationship between the ability of tapasin to bind to TAP and the MHC class I H chain and the ability of tapasin to facilitate class I assembly, we have created novel tapasin mutants and expressed them in 721.220-Ld cells. One mutant has a deletion of nine amino acid residues (tapasin Δ334–342), and the other has amino acid substitutions at positions 334 and 335. In this report we describe the ability of these mutants to interact with Ld and their effects on Ld surface expression. We found that tapasin Δ334–342 was unable to bind to the Ld H chain, and yet it facilitated Ld assembly and expression. Tapasin Δ334–342 was able to bind and stabilize TAP, suggesting that TAP stabilization may be important to the assembly of Ld. Tapasin mutant H334F/H335Y, unlike tapasin Δ334–342, bound to Ld. Expression of tapasin H334F/H335Y in 721.220-Ld reduced the proportion of cell surface open forms of Ld and retarded the migration of Ld from the endoplasmic reticulum. In total, our results indicate that the 334–342 region of tapasin influences Ld assembly and transport.
Differential Evolution and Stability of Epitope-Specific CD8+ T Cell Responses in EBV Infection
Authors: Catalina Michelle D. , Sullivan John L. , Bak Katherine R. , Luzuriaga Katherine 
Published: April 2014

Abstract
Murine models of lymphocytic choriomeningitis virus infection suggest that the memory CD8+ T cell repertoire is reflective of the CD8+ T cell repertoire generated during acute infection. Less is known regarding the evolution of CD8+ T cell repertoires during human viral infections. We therefore examined epitope-specific CD8+ T cell responses in a large cohort of individuals with acute through latent Epstein-Barr virus infection. Using 16 of 20 published EBV epitopes restricted by HLA-A2, HLA-A3 or HLA-B7, we showed that lytic cycle-specific CD8+ T cell responses predominated during acute EBV infection. However, whereas HLA-A2+-restricted BMLF-1-specific CD8+ T cell responses were maintained through latency, HLA-A2+- and HLA-B7+-restricted BZLF-1, as well as HLA-A3+-restricted BRLF-1 CD8+ T cell responses, were generated but not readily maintained. Analyses of CD8+ T cell responses to EBV latent cycle Ags showed delayed detection and lower frequencies of latent epitope-specific CD8+ T cell responses during acute EBV infection, with maintenance of these responses 1 yr post-EBV infection. Early BMLF-1 and EBNA-3A epitope-specific CD8+ T cell frequencies did not correlate with their frequencies at 1 yr postinfection. Interestingly, populations of EBV-specific CD8+ T cells were stable during 20 mo in our long term EBV-seropositive populations, suggesting homeostasis between virus and the host immune system. This study demonstrates that CD8+ T cell repertoires generated during persistent viral infections are not simply reflective of the initial pool of CD8+ T cells and provides evidence that the generation of CD8+ T cell responses to a persistent infection is a dynamic process.
Notch-1 Regulates NF-κB Activity in Hemopoietic Progenitor Cells
Authors: Cheng Pingyan , Zlobin Andrew , Volgina Veronica , Gottipati Sridevi , Osborne Barbara , Simel Erica J. , Miele Lucio , Gabrilovich Dmitry I. 
Published: April 2014

Abstract
We investigated the interaction between two elements critical for differentiation of hemopoietic cells, the Notch-1 receptor and the transcription factor NF-κB. These factors were studied in hemopoietic progenitor cells (HPC) using Notch-1 antisense transgenic (Notch-AS-Tg) mice. DNA binding of NF-κB as well as its ability to activate transcription was strongly decreased in HPC from Notch-AS-Tg mice. NF-κB-driven transcriptional activity was completely restored after transduction of the cells with retroviral constructs containing activated Notch-1 gene. HPC from Notch-AS-Tg mice have decreased levels of several members of the NF-κB family, p65, p50, RelB, and c-Rel and this is due to down-regulation of the gene expression. To investigate functional consequences of decreased NF-κB activity in transgenic mice, we studied LPS-induced proliferation of B cells and GM-CSF-dependent differentiation of dendritic cells from HPC. These two processes are known to be closely dependent on NF-κB. B cells from Notch-AS-Tg mice had almost 3-fold lower response to LPS than B cells isolated from control mice. Differentiation of dendritic cells was significantly affected in Notch-AS-Tg mice. However, it was restored by transduction of activated Notch-1 into HPC. Taken together, these data indicate that in HPC NF-κB activity is regulated by Notch-1 via transcriptional control of NF-κB.
Enforced Expression of GATA-3 Severely Reduces Human Thymic Cellularity
Authors: Taghon Tom , De Smedt Magda , Stolz Frank , Cnockaert Maggy , Plum Jean , Leclercq Georges 
Published: April 2014

Abstract
Following bone marrow transplantation, patients often suffer from immune incompetence by reduced or late T cell development. Moreover, adult bone marrow stem cells have a lower capacity to generate T cells compared with fetal liver- and umbilical cord blood-derived progenitors. Therefore, enhancing thymic-dependent T cell generation might hold great therapeutic potential. GATA-3 is a transcription factor that is essential in T cell development. In this study we examined the therapeutic potential of GATA-3 to enhance T cell generation by overexpressing GATA-3 in T cell progenitors followed by fetal thymic organ culture (FTOC). We observed that early during FTOC, there was an enhanced differentiation toward the double positive stage of T cell development. From day 10 of FTOC, however, overexpression of GATA-3 induced a severe reduction in thymic cellularity, which probably correlates with the absence of a functional TCR-β chain. We further show that the frequency of apoptosis was increased in GATA-3-transduced thymocytes. Despite the absence of a functional TCR-β chain, GATA-3 transduced progenitors were able to differentiate into CD8β+ double positive thymocytes. This study shows that a strictly regulated expression of GATA-3 is essential for normal T cell development and this puts severe restrictions on the potential therapeutic use of continuously overexpressed GATA-3.
IL-12, STAT4-Dependent Up-Regulation of CD4+ T Cell Core 2 β-1,6-n-Acetylglucosaminyltransferase, an Enzyme Essential for Biosynthesis of P-Selectin Ligands
Authors: Lim Yaw-Chyn , Xie Huijuan , Come Carolyn E. , Alexander Stephen I. , Grusby Michael J. , Lichtman Andrew H. , Luscinskas Francis W. 
Published: April 2014

AbstractTCR activation of naive T cells in the presence of IL-12 drives polarization toward a Th1 phenotype and synthesis of P- and E-selectin ligands. Fucosyltransferase VII (Fuc-T VII) and core 2 β-1,6-N-acetylglucosaminyltransferase (C2GnT) are critical for biosynthesis of selectin ligands. P-selectin glycoprotein ligand-1 is the best characterized ligand for P-selectin and also binds E-selectin. The contributions of TCR and cytokine signaling pathways to up-regulate Fuc-T VII and C2GnT during biosynthesis of E- and P-selectin ligands, such as P-selectin glycoprotein ligand 1, are unknown. IL-12 signals via the STAT4 pathway. Here, naive DO11.10 TCR transgenic and STAT4−/− TCR transgenic CD4+ T cells were stimulated with Ag and IL-12 (Th1 condition), IL-4 (Th2), or neutralizing anti-IL-4 mAb only (Th0). The levels of Fuc-T VII and C2GnT mRNA in these cells were compared with their adhesive interactions with P- and E-selectin in vitro under flow. The data show IL-12/STAT4 signaling is necessary for induction of C2GnT, but not Fuc-TVII mRNA, and that STAT4−/− Th1 cells do not traffic normally to sites of inflammation in vivo, do not interact with P-selectin, and exhibit a partial reduction of E-selectin interactions under shear stress in vitro. Ag-specific TCR activation in CD4+ T cells was sufficient to trigger induction of Fuc-TVII, but not C2GnT, mRNA and expression of E-selectin, but not P-selectin, ligands. Thus, Fuc-T VII and C2GnT are regulated by different signals during Th cell differentiation, and both cytokine and TCR signals are necessary for the expression of E- and P-selectin ligands.
TCRA Gene Rearrangement in Immature Thymocytes in Absence of CD3, Pre-TCR, and TCR Signaling
Authors: Mancini Stéphane J. C. , Candéias Serge M. , Di Santo James P. , Ferrier Pierre , Marche Patrice N. , Jouvin-Marche Evelyne 
Published: April 2014

Abstract
During thymocyte differentiation, TCRA genes are massively rearranged only after productively rearranged TCRB genes are expressed in association with pTα and CD3 complex molecules within a pre-TCR. Signaling from the pre-TCR via the CD3 complex is thought to be required to promote TCRA gene accessibility and recombination. However, αβ+ thymocytes do develop in pTα-deficient mice, showing that TCRα-chain genes are rearranged, either in CD4−CD8− or CD4+CD8+ thymocytes, in the absence of pre-TCR expression. In this study, we analyzed the TCRA gene recombination status of early immature thymocytes in mutant mice with arrested thymocyte development, deficient for either CD3 or pTα and γc expression. ADV genes belonging to different families were found rearranged to multiple AJ segments in both cases. Thus, TCRA gene rearrangement is independent of CD3 and γc signaling. However, CD3 expression was found to play a role in transcription of rearranged TCRα-chain genes in CD4−CD8− thymocytes. Taken together, these results provide new insights into the molecular control of early T cell differentiation.
Chromatin Remodeling, Measured by a Novel Real-Time Polymerase Chain Reaction Assay, Across the Proximal Promoter Region of the IL-2 Gene
Authors: Rao Sudha , Procko Erik , Shannon M. Frances 
Published: April 2014

Abstract
The structure of chromatin and its remodeling following activation are important aspects of the control of inducible gene transcription. The IL-2 gene is induced in a cell specific-manner in T cells following an antigenic stimulus. We show, using a novel real-time PCR assay, that significant chromatin remodeling of the IL-2 proximal promoter region occurred upon stimulation of both the murine EL-4 T cell line and primary CD4+ T cells. Chromatin remodeling appears to be limited to the first 300 bp of the proximal promoter region as measured by micrococcal nuclease and restriction enzyme accessibility. Time course studies indicated that chromatin remodeling was observed at 1.5 h postinduction and was maintained for up to 16 h. The remodeling is reversible upon removal of the stimulus. The region immediately upstream from the transcription start site, however, remains accessible for up to 16 h. Upon restimulation, remodeling occurs much more rapidly, consistent with a more rapid rise in IL-2 mRNA levels. Using a number of pharmacological inhibitors we show that remodeling is dependent on the presence of specific transcription factors, but not on the modification of histones. The development of this novel chromatin accessibility assay based on real-time PCR has allowed rapid, sensitive, and quantitative measurements on the IL-2 gene following cellular activation in both T cell lines and primary cells.
An Ancient Lectin-Dependent Complement System in an Ascidian: Novel Lectin Isolated from the Plasma of the Solitary Ascidian, Halocynthia roretzi
Authors: Sekine Hideharu , Kenjo Akira , Azumi Kaoru , Ohi Gota , Takahashi Minoru , Kasukawa Reiji , Ichikawa Narumi , Nakata Munehiro , Mizuochi Tsuguo , Matsushita Misao , Endo Yuichi , Fujita Teizo 
Published: April 2014

Abstract
Mannose-binding lectin (MBL) is a C-type lectin involved in the first line of host defense against pathogens and it requires MBL-associated serine protease (MASP) for activation of the complement lectin pathway. To elucidate the origin and evolution of MBL, MBL-like lectin was isolated from the plasma of a urochordate, the solitary ascidian Halocynthia roretzi, using affinity chromatography on a yeast mannan-Sepharose. SDS-PAGE of the eluted proteins revealed a major band of ∼36 kDa (p36). p36 cDNA was cloned from an ascidian hepatopancreas cDNA library. Sequence analysis revealed that the carboxy-terminal half of the ascidian lectin contains a carbohydrate recognition domain (CRD) that is homologous to C-type lectin, but it lacks a collagen-like domain that is present in mammalian MBLs. Purified p36 binds specifically to glucose but not to mannose or N-acetylglucosamine, and it was designated glucose-binding lectin (GBL). The two ascidian MASPs associated with GBL activate ascidian C3, which had been reported to act as an opsonin. The removal of GBL-MASPs complex from ascidian plasma using Ab against GBL inhibits C3-dependent phagocytosis. These observations strongly suggest that GBL acts as a recognition molecule and that the primitive complement system, consisting of the lectin-proteases complex and C3, played a major role in innate immunity before the evolution of an adaptive immune system in vertebrates.
IL-2 During In Vitro Priming Promotes Subsequent Engraftment and Successful Adoptive Tumor Immunotherapy by Persistent Memory Phenotypic CD8+ T Cells
Authors: Bathe Oliver F. , Dalyot-Herman Nava , Malek Thomas R. 
Published: April 2014

AbstractAdoptive T cell tumor immunotherapy potentially consists of two protective components by the transferred effector cells, the immediate immune response and the subsequent development of memory T cells. The extent by which adoptively transferred CD8+ CTL are destined to become memory T cells is ambiguous as most studies focus on the acute effects on tumor shortly following adoptive transfer. In this study we show that a substantial fraction of the input CTL develop into memory cells that reject a s.c. tumor challenge. The use of exogenous IL-2 or a combination of IL-2 and IL-4, but not solely IL-4, during the ex vivo culture for the CTL inoculation was necessary for efficient development of CD8+ memory T cells. Thus, an important component of adoptive immunotherapy using CTL is the production of CD8+ Ag-specific memory cells which is primarily favored by IL-2 receptor signaling during ex vivo generation of the effector CTL.