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Cytokine Receptors (cytokine + receptor)
Selected AbstractsPhage ,C31 integrase-mediated genomic integration of the common cytokine receptor gamma chain in human T-cell linesTHE JOURNAL OF GENE MEDICINE, Issue 5 2006Yoshinori Ishikawa Abstract Background X-linked severe combined immunodeficiency (SCID-X1, X-SCID) is a life-threatening disease caused by a mutated common cytokine receptor , chain (,c) gene. Although ex vivo gene therapy, i.e., transduction of the ,c gene into autologous CD34+ cells, has been successful for treating SCID-X1, the retrovirus vector-mediated transfer allowed dysregulated integration, causing leukemias. Here, to explore an alternative gene transfer methodology that may offer less risk of insertional mutagenesis, we employed the ,C31 integrase-based integration system using human T-cell lines, including the ,c-deficient ED40515(-). Methods A ,C31 integrase and a neor gene expression plasmid containing the ,C31 attB sequence were co-delivered by electroporation into Jurkat cells. After G418 selection, integration site analyses were performed using linear amplification mediated-polymerase chain reaction (LAM-PCR). ED40515(-) cells were also transfected with a ,c expression plasmid containing attB, and the integration sites were determined. IL-2 stimulation was used to assess the functionality of the transduced ,c in an ED40515(-)-derived clone. Results Following co-introduction of the ,C31 integrase expression plasmid and the plasmid carrying attB, the efficiency of integration into the unmodified human genome was assessed. Several integration sites were characterized, including new integration sites in intergenic regions on chromosomes 13 and 18 that may be preferred in hematopoietic cells. An ED40515(-) line bearing the integrated ,c gene exhibited stable expression of the ,c protein, with normal IL-2 signaling, as assessed by STAT5 activation. Conclusions This study supports the possible future use of this ,C31 integrase-mediated genomic integration strategy as an alternative gene therapy approach for treating SCID-X1. Copyright © 2006 John Wiley & Sons, Ltd. [source] Production and partial characterization of mouse monoclonal antibodies recognizing common cytokine receptor gamma chain (,c) of human, mouse and primate origin,APMIS, Issue 10 2001KAROLINA LUNDIN Monoclonal antibodies specific for the common cytokine receptor gamma chain, ,c, were produced using traditional hybridoma technology. Fusion of P3X63-Ag8.653 myeloma cells with splenocytes from Balb/c mice immunized with Spodoptera frugiperda insect cells infected with the recombinant baculovirus VL1392-hIL-2R, resulted in several hybridoma cell clones producing monoclonal ,c -specific antibodies. Four of these antibody-producing clones, IIIC3, IIIE8, IG3 and IF10C5, were further characterized by immunoblotting, flow cytometry and ELISA. Data are presented demonstrating that the generated monoclonal antibodies can identify the extracellular domain of the common cytokine receptor , chain of human and mouse origin, and two of the antibodies recognize ,c of primate origin as well. [source] Genetic variations associated with psoriasis and psoriatic arthritis found by genome-wide associationDERMATOLOGIC THERAPY, Issue 2 2010Kristina Callis Duffin ABSTRACT Psoriasis and psoriatic arthritis are immune disorders with a complex polygenic basis. HLA-Cw6, which lies in the major histocompatibility region on chromosome 6, is considered the major genetic determinant of psoriasis. Recent genome-wide association studies have identified new variants outside of the MHC with relevance to the immunology of psoriasis. Variants in or near genes that encode subunits of cytokines (IL12B, IL23A) or cytokine receptors (IL23R) are interesting given that the gene product of IL12B, p40, is the target of a recently approved monoclonal antibody therapy for psoriasis (ustekinumab). Association with psoriasis and psoriatic arthritis has been found in TNFAIP3 and TNFIP1, ubiquitin ligases in the NF-,B pathway, and IL13, a Th2 cytokine. Copy number variation of human beta-defensin and late cornified envelope genes also associate with psoriasis. Many of these genetic variations also associate with immune disorders considered psoriatic co-morbidities, including Crohn's disease and diabetes. [source] Extensive flow cytometric characterization of plasmacytoid dendritic cell leukemia cellsEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2005Laszlo Gopcsa Abstract:,Objectives:,Accumulating evidence suggests that non-T, non-B cell CD4+CD56+ neoplasms with lymphoblastic morphology include clinically and immunophenotypically diverse entities. Although their cells of origin or classification are still controversial several entities clearly represent a distinct type of neoplasms that are clinically aggressive. Methods:,In this work we present the immunophenotypic and genotypic features of bone marrow (BM), peripheral blood (PB), lymph node and skin lymphocytes from a patient diagnosed as plasmacytoid dendritic cell leukemia involving the skin, BM, PB, lymph nodes, liver and spleen. For determination of immunophenotypic characteristics of malignant plasmacytoid dendritic cells 73 monoclonal antibodies detecting lineage markers, chemokine receptors, cytokine receptors, activation, and co-stimulatory molecules were used. Results and conclusion:,The malignant cells proved to express CD4+, CD56+ lineage negative leukemia phenotype characteristically positive for CD36, CD38, CD40, CD45, CD45RA, CD68, CD123, CD184, HLA-DR, BDCA2, and granzyme-B corresponding to the preplasmacytoid dendritic cell developmental stage. The presence of CD11a/CD18, CD84, CD91, CD95, ,v,5, CDw197, and the absence of CD52 and CD133 in this case can be regarded as additional features of malignant cells. Completing the immunophenotypes with multidrug resistance function can provide additional information for characterizing pDC leukemia. [source] Two-phase liquid culture system models normal human adult erythropoiesis at the molecular levelEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5 2000Sharon H. Pope Abstract: We have studied the patterns of expression of various genes during maturation of normal human adult erythroid precursors cultured in a two-phase liquid culture method. In the first phase, peripheral blood mononuclear cells are cultured for one week in the presence of a combination of growth factors, but not erythropoietin (Epo). In Phase II, Epo is included in the medium. Cell samples were taken throughout phase II, and expression of globins, transcription factors, and cytokine receptors was assayed by RT-PCR and quantified by phosphor imaging. We have divided phase II into stages: early (days 0,5), intermediate (days 6,10) and late (days 11,15) and measured maximum expression of each gene. During early phase II, ,-globin, Sp1, and GATA-2 mRNAs were expressed at their highest levels. As the cells matured during the intermediate period, GATA-2 levels remained high, and then declined, while the transcription factors GATA-1, EKLF, NF-E2, and the Epo receptor (EpoR) reached maximum expression. In late phase II, ,-globin increased and reached its maximum level of expression. This erythroid culture system appears to recapitulate normal adult erythropoiesis at the molecular level, and thus may be a suitable model to examine the molecular basis of severe congenital or acquired disorders oferythropoiesis. [source] Secondary structure assignment of mouse SOCS3 by NMR defines the domain boundaries and identifies an unstructured insertion in the SH2 domainFEBS JOURNAL, Issue 23 2005Jeffrey J. Babon SOCS3 is a negative regulator of cytokine signalling that inhibits Janus kinase-signal transduction and activator of transcription (JAK-STAT) mediated signal tranduction by binding to phosphorylated tyrosine residues on intracellular subunits of various cytokine receptors, as well as possibly the JAK proteins. SOCS3 consists of a short N-terminal sequence followed by a kinase inhibitory region, an extended SH2 domain and a C-terminal suppressor of cytokine signalling (SOCS) box. SOCS3 and the related protein, cytokine-inducible SH2-containing protein, are unique among the SOCS family of proteins in containing a region of mostly low complexity sequence, between the SH2 domain and the C-terminal SOCS box. Using NMR, we assigned and determined the secondary structure of a murine SOCS3 construct. The SH2 domain, unusually, consists of 140 residues, including an unstructured insertion of 35 residues. This insertion fits the criteria for a PEST sequence and is not required for phosphotyrosine binding, as shown by isothermal titration calorimetry. Instead, we propose that the PEST sequence has a functional role unrelated to phosphotyrosine binding, possibly mediating efficient proteolytic degradation of the protein. The latter half of the kinase inhibitory region and the entire extended SH2 subdomain form a single ,-helix. The mapping of the true SH2 domain, and the location of its C terminus more than 50 residues further downstream than predicted by sequence homology, explains a number of previously unexpected results that have shown the importance of residues close to the SOCS box for phosphotyrosine binding. [source] Mutations in severe combined immune deficiency (SCID) due to JAK3 deficiencyHUMAN MUTATION, Issue 4 2001Luigi D. Notarangelo Abstract During the last 10 years, an increasing number of genes have been identified whose abnormalities account for primary immunodeficiencies, with defects in development and/or function of the immune system. Among them is the JAK3 -gene, encoding for a tyrosine kinase that is functionally coupled to cytokine receptors which share the common gamma chain. Defects of this gene cause an autosomal recessive form of severe combined immunodeficiency with almost absent T-cells and functionally defective B-cells (T,B+ SCID). Herewith, we present molecular information on the first 27 unique mutations identified in the JAK3 gene, including clinical data on all of the 23 affected patients reported so far. A variety of mutations scattered throughout all seven functional domains of the protein, and with different functional effects, have been identified. Availability of a molecular screening test, based on amplification of genomic DNA, facilitates the diagnostic approach, and has permitted recognition that JAK3 deficiency may also be associated with atypical clinical and immunological features. Development of a structural model of the JAK3 kinase domain has allowed characterization of the functional effects of the various mutations. Most importantly, molecular analysis at the JAK3 locus results in improved genetic counseling, allows early prenatal diagnosis, and prompts appropriate treatment (currently based on hematopoietic stem cell transplantation) in affected families. Hum Mutat 18:255,263, 2001. © 2001 Wiley-Liss, Inc. [source] Instructive cytokine signals in dendritic cell lineage commitmentIMMUNOLOGICAL REVIEWS, Issue 1 2010Michael A. Schmid Summary:, Clarifying the signals that lead to dendritic cell (DC) development and identifying cellular intermediates on their way to DC differentiation are essential steps to understand the dynamic regulation of number, localization, and functionality of these cells. In the past decade, much knowledge on cytokines, transcription factors, and successive progenitors involved in steady-state and demand-adapted DC development was gained. From the stage of multipotent progenitors, DCs are generated from Flt3+ intermediates, irrespective of lymphoid or myeloid commitment, making fms-related tyrosine kinase 3 ligand one of the major regulators for DC development. Additional key cytokines involved are granulocyte,macrophage colony-stimulating factor (GM-CSF) and M-CSF, with each being essential for particular DC subsets and leading to specific activation of downstream transcription factors. In this review, we seek to draw an integrative view on how instructive cytokine signals acting on intermediate progenitors might lead to the generation of specific DC subsets in steady-state and during inflammation. We hypothesize that the lineage potential of a progenitor might be determined by the set of cytokine receptors expressed that make it responsive to further receive lineage instructive signals. Commitment to a certain lineage might consequently occur when lineage-relevant cytokine receptors are further upregulated and others for alternative lineages are lost. Along this line, we emphasize the role that diverse microenvironments have in influencing the generation of DC subsets with specific functions throughout the body. [source] T-cell receptor proximal signaling via the Src-family kinases, Lck and Fyn, influences T-cell activation, differentiation, and toleranceIMMUNOLOGICAL REVIEWS, Issue 1 2009Robert J. Salmond Summary:, T-cell development in the thymus and activation of mature T cells in secondary lymphoid organs requires the ability of cells to respond appropriately to environmental signals at multiple stages of their development. The process of thymocyte selection insures a functional T-cell repertoire, while activation of naive peripheral T cells induces proliferation, gain of effector function, and, ultimately, long-lived T-cell memory. The T-cell immune response is initiated upon engagement of the T-cell receptor (TCR) and coreceptor, CD4 or CD8, by cognate antigen/major histocompatibility complexes presented by antigen-presenting cells. TCR/coreceptor engagement induces the activation of biochemical signaling pathways that, in combination with signals from costimulator molecules and cytokine receptors, direct the outcome of the response. Activation of the src- family kinases p56lck (Lck) and p59fyn (Fyn) is central to the initiation of TCR signaling pathways. This review focuses on our current understanding of the mechanisms by which these two proteins orchestrate T-cell function. [source] Regulation of the immune response by stress-activated protein kinasesIMMUNOLOGICAL REVIEWS, Issue 1 2009Mercedes Rincón Summary:, Activation of immune cells to mediate an immune response is often triggered by potential ,danger' or ,stress' stimuli that the organism receives. Within the mitogen-activated protein kinases (MAPKs) family, the stress-activated protein kinase (SAPK) group was defined as group of kinases that activated by stimuli that cause cell stress. In the immune cells, SAPKs are activated by antigen receptors (B- or T-cell receptors), Toll-like receptors, cytokine receptors, and physical,chemical changes in the environment among other stimuli. The SAPKs are established to be important mediators of intracellular signaling during adaptive and innate immune responses. Here we summarize what is currently known about the role of two sub-groups of SAPKs , c-Jun NH2 -terminal kinase and p38 MAPK-in the function of specific components of the immune system and the overall contribution to the immune response. [source] The role of the preBCR, the interleukin-7 receptor, and homotypic interactions during B-cell developmentIMMUNOLOGICAL REVIEWS, Issue 1 2000Angela Stoddart Summary: Considerable progress has been made in defining intermediate stages in the process leading from stem cells to mature B cells. Cell-bound and secreted molecules direct the progression through these stages and regulate the selection of clones from which the immune repertoire emerges. In fact, a myriad of signals derived from B-cell progenitors themselves and the microenvironment in which they develop direct the differentiation process. These signals are provided by B-cell antigen receptors (BCR) and their surrogates, and by adhesion and cytokine receptors. The co-operation of these receptors to control survival, expansion, and differentiation of early B-cell progenitors is the topic of this review. Specifically, we will summarize recent findings from our laboratory demonstrating that preBCR expression lowers the threshold for interleukin (IL)-7 responsiveness. How signals initiated by these receptors may intersect at this critical point of B-cell selection will be discussed. At the stage following IL-7 responsiveness we have shown that interactions between B-cell progenitors themselves promote their differentiation to immunoglobulin-secreting B cells. We propose that one function of stromal cells, known to be central to B lymphopoiesis, is to promote critical preB,preB homotypic interactions and ensuing signals. [source] Human T-cell leukemia virus type-I Tax induces expression of interleukin-6 receptor (IL-6R): Shedding of soluble IL-6R and activation of STAT3 signalingINTERNATIONAL JOURNAL OF CANCER, Issue 4 2006Sankichi Horiuchi Abstract Human T-cell leukemia virus type-I (HTLV-I) encodes for the viral protein Tax, which is known to significantly disrupt transcriptional control of cytokines, cytokine receptors and other immuno-modulatory proteins in T cells. Specific dysregulation of these factors can alter the course and pathogenesis of infection. Soluble interleukin-6 receptor (sIL-6R) was shown to circulate at elevated levels in HTLV-I-infected patients, and high expressions of IL-6R and sIL-6R by HTLV-I-infected T cells were clinically and experimentally associated with Tax activity. To examine roles of Tax in expression of the IL-6R gene, the JPX-9 cell line was used, which is derived from Jurkat cell line expressing Tax cDNA. Over-expression of Tax enhanced IL-6R expression but not in Tax mutant JPX-9/M cell line. The clinical relevance of these observations was further demonstrated by ELISA using sera obtained from HTLV-I-infected patients. Our results revealed that sIL-6R levels were apparently elevated in HAM/TSP patients who were expressing Tax in their cells, while ATL patients' cells barely expressed Tax. HTLV-I-infected T-cell lines stimulated by IL-6/sIL-6R showed gp130-mediated STAT3 activity. IL-6/sIL-6R enhanced proliferation of HTLV-I-infected T cells in association with activation of STAT3. Consequently, Tax-mediated regulations of IL-6R and sIL-6R observed in HTLV-I-associated disorders may contribute to proliferation of HTLV-I-infected T cells through activation of inducible STAT3, and ultimately affect malignant growth and transformation of T cells by HTLV-I. © 2006 Wiley-Liss, Inc. [source] cDNA-arrays and real-time quantitative PCR techniques in the investigation of chronic achilles tendinosisJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2003Håkan Alfredson The aetiology and pathogenesis of chronic painful Achilles tendinosis are unknown. This investigation aimed to use cDNA arrays and real-time quantitative polymerase chain reaction (real-time PCR) technique to study tendinosis and control tissue samples. Five patients (females mean age 57.1 ± 4.3 (years ±SD)) with chronic painful Achilles tendinosis were included. From all patients, one biopsy was taken from the area with tendinosis and one from a clinically normal area (control) of the tendon. The tissue samples were immediately immersed in RNAlater and frozen at ,80°C until RNA extraction. Portions of pooled RNA from control and tendinosis sites, respectively, were transcribed to cDNA, radioactively labelled (32P), hybridized to cDNA expression arrays, and exposed to phosphoimager screens over night. Expressions of specific genes, shown to be regulated in the cDNA array analysis, were analyzed in the individual samples using real-time PCR. cDNA arrays showed that gene expressions for matrix-metalloproteinase-2 (MMP-2), fibronectin subunit B (FNRB), vascular endothelial growth factor (VEGF), and mitogen-activated protein kinase p38 (MAPKp38) were up-regulated, while matrix-metalloproteinase-3 (MMP-3) and decorin were down-regulated, in tendinosis tissue compared with control tissue. Using real-time PCR, , and , patients showed up-regulation of MMP-2 and FNRB mRNA, respectively. For decorin, VEGF, and MAPKp38, real-time PCR revealed a great variability among patients. Interestingly, the mRNAs for several cytokines and cytokine receptors were not regulated, indicating the absence of an inflammatory process in chronic painful Achilles tendinosis. In conclusion, cDNA-arrays and real-time PCR can be used to study differences in gene expression levels between tendinosis and control tendon tissue. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Human mast cells express receptors for IL-3, IL-5 and GM-CSF; a partial map of receptors on human mast cells cultured in vitroALLERGY, Issue 10 2004C. Dahl Background:, Mast cells have long been recognized as the principal cell type that initiates the inflammatory response characteristic of acute allergic type 1 reactions. Our goal has been to further characterize maturation of progenitors to mast cells. Methods:, Mast cells were cultured from human cord blood derived CD133+ progenitors. Mast cell function was tested using histamine release. During differentiation mast cells surface marker expression was monitored by flow cytometry. Results:, CD133+ progenitors expressed the early haematopoietic and myeloid lineage markers CD34, CD117, CD13 and CD33. Mature mast cells expressed CD117, CD13 and CD33, and expression of the high affinity immunoglobulin E recpetor Fc,RI increased during culture. Cytokine receptors interleukin (IL)-5R, IL-3R, granulocyte-macrophage-colony stimulating factor (GM-CSF)R and IL-18R were expressed at high levels during maturation. Chemokine receptors CXCR4 and CXCR2 were highly expressed on both newly purified CD133+ cells and mature cells. Conclusion:, Human mast cells can be cultured from a CD34+/CD117+/CD13+/CD33+ progenitor cell population in cord blood that is tryptase and chymase negative. Developing and mature mast cells express a wide range of chemokine and cytokine receptors. We found high levels of expression of CD123, IL-5R and GM-CSF receptors, also found on eosinophils and basophils, and high levels of expression of the receptor for the inflammatory cytokine IL-18. [source] Modeling the proteome of a Marek's disease transformed cell line: a natural animal model for CD30 overexpressing lymphomasPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 8 2007Joram J. Buza Dr. Abstract Marek's disease (MD) in the chicken, caused by the highly infectious MD ,-herpesvirus (MDV), is both commercially important and a unique, naturally occurring model for human T-cell lymphomas overexpressing the Hodgkin's disease antigen, CD30. Here, we used proteomics as a basis for modeling the molecular functions and biological processes involved in MDV-induced lymphomagenesis. Proteins were extracted from an MDV-transformed cell line and were then identified using 2-D LC-ESI-MS/MS. From the resulting 3870 cellular and 21 MDV proteins we confirm the existence of 3150 "predicted" and 12 "hypothetical" chicken proteins. The UA-01 proteome is proliferative, differentiated, angiogenic, pro-metastatic and pro-immune-escape but anti-programmed cell death, -anergy, -quiescence and -senescence and is consistent with a cancer phenotype. In particular, the pro-metastatic integrin signaling pathway and the ERK/MAPK signaling pathways were the two predominant signaling pathways represented. The cytokines, cytokine receptors, and their related proteins suggest that UA-01 has a regulatory T-cell phenotype. [source] Up-regulation of cytokines and chemokines predates the onset of rheumatoid arthritisARTHRITIS & RHEUMATISM, Issue 2 2010Heidi Kokkonen Objective To identify whether cytokines, cytokine-related factors, and chemokines are up-regulated prior to the development of rheumatoid arthritis (RA). Methods A nested case,control study was performed in 86 individuals who had donated blood samples before experiencing any symptoms of disease (pre-patients) and 256 matched control subjects (1:3 ratio). In 69 of the pre-patients, blood samples were also obtained at the time of the diagnosis of RA. The plasma levels of 30 cytokines, related factors, and chemokines were measured using a multiplex system. Results The levels of several of the cytokines, cytokine receptors, and chemokines were significantly increased in individuals before disease onset compared with the levels in control subjects; i.e., those representing signs of general immune activation (interleukin-1, [IL-1,], IL-2, IL-6, IL-1 receptor antagonist, and tumor necrosis factor), activation of Th1 cells (interferon-,, IL-12), Th2 cells (IL-4, eotaxin), Treg cells (IL-10), bone marrow,derived factors (IL-7, granulocyte,macrophage colony-stimulating factor, and granulocyte colony-stimulating factor), as well as chemokines (monocyte chemotactic protein 1 and macrophage inflammatory protein 1,). The levels were particularly increased in anti,cyclic citrullinated peptide antibody, and rheumatoid factor,positive individuals, and the concentration of most of these increased further after disease onset. The concentration of IL-17 in individuals before disease onset was significantly higher than that in patients after disease onset. Individuals in whom RA subsequently developed were discriminated from control subjects mainly by the presence of Th1 cells, Th2 cells, and Treg cell,related cytokines, while chemokines, stromal cell,derived cytokines, and angiogenic-related markers separated patients after the development of RA from individuals before the onset of RA. Conclusion Individuals in whom RA later developed had significantly increased levels of several cytokines, cytokine-related factors, and chemokines representing the adaptive immune system (Th1, Th2, and Treg cell,related factors); after disease onset, the involvement and activation of the immune system was more general and widespread. [source] Gene expression of cytokine receptors in HL60 cells exposed to a 50 Hz magnetic fieldBIOELECTROMAGNETICS, Issue 5 2002Jiliang Zhou Abstract The effects of a 50 Hz extremely low frequency (ELF) sinusoidal magnetic field (MF) on the expression of genes relating to cytokine receptors were studied in HL60 cells. Transcription levels of tumor necrosis factor receptor (TNFR) p55 and p75, interleukin-6 receptor-, (IL-6R,) and transforming growth factor-, receptor 1 (TGF,R1) were quantified in cells exposed to an intensity of 0.1 or 0.8 mT for periods ranging from 30 min to 72 h. Cells treated with 10 nM of phorbol 12-myristate 13-acetate (PMA) for 8 h served as a positive control. Gene expression values were assessed by the ribonuclease protection assay (RPA) and normalized to those of the noninducible gene GAPDH. The results showed that MF exposure at 0.1 and 0.8 mT for 72 h increased TNFR p75 and IL-6R, mRNA expression in HL60 cells. No significant change in gene expression levels of TNFR p55 and TGF,R1 was observed under any of the exposure conditions. In addition, we report here for the first time that IL-6R, mRNA expression can be suppressed by PMA in HL60 cells. Bioelectromagnetics 23:339,346, 2002. © 2002 Wiley-Liss, Inc. [source] Ras and Signal Transducer and Activator of Transcription (STAT) Are Essential and Sufficient Downstream Components of Janus Kinases in Cell ProliferationCANCER SCIENCE, Issue 5 2000Rumiko Mizuguchi Cytokines exert their activities in cell growth and differentiation by binding specific cell membrane receptors. Janus kinases (JAKs) are cytoplasmic protein tyrosine kinases that physically interact with intracellular domains of the cytokine receptors and they play crucial roles in transducing signals triggered by the cytokine-receptor interaction. We have previously shown that conditional activation of JAK through membrane-proximal dimerization confers cytokine-independence on interleukin-3 (IL-3)-dependent Ba/F3 lymphoid cells and that the cytokine-independent proliferation is completely inhibited by dominant negative Ras. In this work, we demonstrate that ectopic expression of a dominant negative form of Stat5, a major signal transducer and activator of transcription (STAT) expressed in Ba/F3 cells, also inhibits JAK-triggered mitogenesis. In contrast, overexpression of constitutively active Ras or conditional activation of Stat5 by chemical dimerization fails to confer cytokine-independence. However, concomitant activation of ectopic Ras and Stat5 molecules in Ba/F3 cells suffices for cell proliferation in the absence of IL-3. Our results indicate that Ras and STAT are essential and sufficient components of JAK-triggered mitogenesis. Our findings further indicate that the cytokine signal bifurcates into Ras and STAT pathways following JAK activation. [source] Cell volume and rate of proliferation, but not protein expression pattern, distinguish pup/intimal smooth muscle cells from subcultured adult smooth muscle cellsCELL PROLIFERATION, Issue 5 2001E. McKilligin Smooth muscle cells from neonatal rats and from injured blood vessels grow with a characteristic cobblestone morphology that distinguishes them from adult smooth muscle cells. This has led to the proposition that there are two distinct types of smooth muscle cells with different proliferative capacity. Here we systematically compare the properties of subcultured adult smooth muscle cells in culture and clonal lines of cobblestone smooth muscle cells from both neonatal rats and injured vessels. The cobblestone smooth muscle cells have a significantly smaller average cell volume, estimated using two different flow cytometry measurements. However, the two types of smooth muscle cells have indistinguishable protein expression patterns when the levels of more than 20 different proteins (including cytoskeletal proteins, matrix proteins, cytokines, cytokine receptors, adhesion molecules and enzymes) are measured by quantitative immunofluorescence. Furthermore, in contrast to previous observations, we demonstrate that both types of smooth muscle cells secrete a powerful mitogenic activity. The higher cell density achieved by the cobblestone smooth muscle cells in culture was responsible for the earlier reports that this mitogenic activity was secreted only by cobblestone smooth muscle cells. We conclude that many of the differences seen between cobblestone smooth muscle cells and adult smooth muscle cells in vitro (proliferation rate, morphology, protein expression pattern, secretion of mitogenic activity) could be attributable to a stable difference in the median cell volume of the cultures. [source] Molecular Characterization of the NCoA-1,STAT,6 InteractionCHEMBIOCHEM, Issue 8 2008Markus Seitz Abstract Many protein,protein interactions involved in cell signalling, cell adhesion and regulation of transcription are mediated by short ,-helical recognition motifs with the sequence Leu-Xaa-Xaa-Leu-Leu (LXXLL, where Xaa is any amino acid). Originally observed in cofactors that interact with hormone-activated nuclear receptors, LXXLL motifs are now known to occur in many transcription factors, including the STAT family, which transmit signals from activated cytokine receptors at the cell surface to target genes in the nucleus. STAT,6 becomes activated in response to IL-4 and IL-13, which regulate immune and anti-inflammatory responses. Structural studies have revealed how an LXXLL motif located in 2.5 turns of an ,-helical peptide derived from STAT,6 provide contacts through the leucine side chains to the coactivator of transcription, NCoA-1. However, since many protein,protein interactions are mediated by LXXLL motifs, it is important to understand how specificity is achieved in this and other signalling pathways. Here, we show that energetically important contacts between STAT,6 and NCoA-1 are made in residues that flank the LXXLL motif, including the underlined residues in the sequence LLPPTEQDLTKLL. We also demonstrate how the affinity for NCoA-1 of peptides derived from this region of STAT,6 can be significantly improved by optimising knobs-into-holes contacts on the surface of the protein. The results provide important new insights into the origins of binding specificity, and might be of practical value in the design of novel small-molecule inhibitors of this important protein,protein interaction. [source] Gene expression profile in a case of primary cutaneous CD30-negative large T-cell lymphoma with a blastic phenotypeCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 2 2001T. Murakami A 65-year-old Japanese woman presented with disseminated erythematous patches, plaques, and nodules on the trunk and limbs. Histological examination showed diffuse and dense infiltrates located in the dermis and subcutis, composed of large pleomorphic T lymphocytes. Immunohistochemically, neoplastic cells were positive for blastic T-cell markers, but negative for CD30 (Ki-1) antigen. Based on the clinicopathological findings, a diagnosis of primary cutaneous large T-cell lymphoma was made. Despite systemic chemotherapy, the patient died 7 months after diagnosis. Gene expression profiling using complementary DNA microarrays indicated significantly increased expression of an apoptosis-inhibitory protein and certain cyokines and cytokine receptors (e.g. MCP-1, MCP-2, IP-10, and IL-2R,) in the tumour-indurated skin. Comprehensive gene expression patterning in additional cases may provide useful information regarding the biological and clinical behaviour of aggressive cutaneous lymphomas such as CD30-negative large T-cell lymphoma. [source] ORIGINAL ARTICLE: Contribution of Interferon-, Receptor 1 Gene Polymorphisms to Pre-Eclampsia in ChinaAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 4 2010Li-Juan Chen Citation Chen L-J, Gao H, Zhou H, Zou L, Zou P. Contribution of interferon-, receptor 1 gene polymorphisms to pre-eclampsia in China. Am J Reprod Immunol 2010; 63: 331,338 Problem, As gene polymorphisms of cytokines receptors have been found to significantly influence cell responses to cytokines, the aim of this study was to test the hypothesis that IFN-, receptor 1 (IFNGR1) gene polymorphisms may contribute to the pathogenesis of pre-eclampsia. Method of study, One hundred and sixty-four pre-eclamptic patients (121 patients with mild pre-eclampsia and 43 patients with severe pre-eclampsia) and 171 controls were included. Polymorphisms of the IFNGR1 gene at positions ,611, ,270, +56 and +95 were genotyped with the matrix-assisted laser desorption/ionization time of flight mass spectrometry. Results, This study showed a positive association between ,56C/C genotype (OR = 1.7; 95% CI = 1.1,2.7) and pre-eclampsia. Although the genotype frequencies (except for ,56C/C) of the two polymorphisms were comparable between cases and controls, higher frequency of the ,611A/,56C haplotype (OR = 1.450; 95% CI = 1.070,1.966) was noticed in patients versus controls. All patients and controls were homozygous for the ,270T/T and +95T/T genotypes. Specifically, the frequency of the ,56C allele (OR = 1.838; 95% CI = 1.127,2.995) was higher among patients with severe pre-eclampsia. Conclusion, The IFNGR1 gene polymorphisms may contribute to the pathogenesis of pre-eclampsia in our population. [source] | ||||||||||||||||||||||||||||