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Sidney Pestka - One of the best experts on this subject based on the ideXlab platform.
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Modulation of the activation of Stat1 by the Interferon-Gamma Receptor complex.
Cell research, 2006Co-Authors: Christopher D. Krause, Sergei V. Kotenko, Sidney PestkaAbstract:The activation of Stat1 by the Interferon-Gamma (IFN-gamma) Receptor complex is responsible for the transcription of a significant portion of IFN-gamma induced genes. Many of these genes are responsible for the induction of an apoptotic state in response to IFN-gamma. In the absence of Stat1 activation, IFN-gamma instead induces a proliferative response. Modifying Stat1 activation by IFN-gamma may have pharmacological benefits. We report that the rate of activation of Stat1 can be altered in HeLa cells by overexpressing either the IFN-gammaR1 chain or the IFN-gammaR2 chain. These alterations occur in hematopoietic cell lines: Raji cells and monocytic cell lines, which have average and above-average IFN-gammaR2 surface expression, activate Stat1 similarly to HeLa cells and HeLa cells overexpressing IFNgammaR2, respectively. The rapid Stat1 activation seen in HeLa cells can be inhibited by overexpressing a chimeric IFN-gammaR2 chain that does not bind Jak2 or (when high concentrations of IFN-gamma are used) by overexpressing IFN-gammaR1. These data are consistent with a model in which the recruitment of additional Jak2 activity to a signaling complex accelerates the rate of Stat1 activation. We conclude that the rate of activation of Stat1 in cells by IFN-gamma can be modified by regulating either Receptor chain and speculate that pharmacological agents which modify Receptor chain expression may alter IFN-gamma Receptor signal transduction.
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The structure of the gene for the second chain of the human Interferon-Gamma Receptor.
The Journal of biological chemistry, 1996Co-Authors: Shinjae Rhee, Zlatko Dembic, Christoph Ebensperger, Sidney PestkaAbstract:Abstract The gene for the second chain of the human interferon-γ Receptor was analyzed from cosmid DNA clones. The gene spans over 33 kilobases of DNA and contains seven exons. The signal peptide is encoded by exons 1 and 2, the extracellular domain by exons 2, 3, 4, 5, and by part of 6. Exon 6 also encodes the whole transmembrane domain and part of the intracellular domain. Exon 7 encodes the remainder of the intracellular domain and contains the 3′-untranslated region. The sequences at the exon/intron boundaries are well conserved with respect to canonical acceptor/donor sites (AG/GT). The 5′-flanking region was sequenced and analyzed for transcription factor binding sites. No TATA or CAAT boxes in the promoter region were identified. Consistent with the lack of a TATA box, analysis of the mRNAs by primer extension showed multiple transcription start sites. Promoter activity of the 5′-flanking region was investigated with a luciferase reporter gene and the cytomegalovirus minimal promoter. Segments of the 5′ region with promoter activity were identified.
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Sublocalization of the human Interferon-Gamma Receptor accessory factor gene and characterization of accessory factor activity by yeast artificial chromosomal fragmentation.
Journal of Biological Chemistry, 1994Co-Authors: Jeffry R. Cook, Stuart L. Emanuel, Barbara Schwartz, S Rhee, Robert J. Donnelly, Thomas M Mariano, Sidney PestkaAbstract:Abstract A chromosomal fragmentation procedure was employed to produce a deletion set of yeast artificial chromosomes (YACs) from a parental YAC, GART D142H8, known to map to human chromosome 21q and to encode the human Interferon-Gamma Receptor (Hu-IFN-gamma R) accessory factor gene as well as the phosphoribosylglycinamide formyltransferase (GART) gene. When expressed in Chinese hamster ovary cells, these deleted YACs retain accessory factor activity, as judged by major histocompatibility complex class I antigen inducibility, until the deletions from the acentric end exceed 390 kilobases (kb). Therefore, the accessory factor (AF-1) gene can be localized to a 150-kb region at the left (centric) end of the parental 540-kb GART YAC. Cells containing functional YACs are also able to induce the ISGF3 gamma and gamma-activated factor (GAF) transcription factors, but were not protected against encephalomyocarditis virus (EMCV) upon treatment with Hu-IFN-gamma. Therefore, the Hu-IFN-gamma R and the AF-1 are sufficient for some, but not all, of the actions of Hu-IFN-gamma. We postulate that an additional accessory factor (AF-2) required for antiviral activity against EMCV is encoded on chromosome 21q.
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Chimeric Interferon-Gamma Receptors demonstrate that an accessory factor required for activity interacts with the extracellular domain.
The Journal of biological chemistry, 1992Co-Authors: Y Hibino, Thomas M Mariano, C S Kumar, D H Lai, Sidney PestkaAbstract:Abstract We determined the species specificity and function of structural domains of the Interferon-Gamma Receptor (IFN-gamma R) by construction of human/murine chimeric IFN-gamma R cDNA clones and their expression in various cells. We demonstrate that we can reconstitute a biologically active IFN-gamma R in eukaryotic cells with chimeric Receptors as long as the extracellular domain and an accessory factor are from the same species. These results indicate that the extracellular domain of the Receptor interacts directly or indirectly with the species-specific accessory factor.
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Human interferon omega (omega) binds to the alpha/beta Receptor.
The Journal of biological chemistry, 1991Co-Authors: I Flores, T M Mariano, Sidney PestkaAbstract:Abstract It was proposed that human interferon omega (omega) binds to the interferon alpha/beta Receptor but not to the interferon gamma Receptor. However, since no studies were performed to provide direct evidence for this hypothesis, we carried out cross-linking experiments and saturation binding assays between a 32P-labeled human interferon-alpha (Hu-IFN-alpha) and unlabeled Hu-IFN-alpha A, -beta, -gamma, and -omega. These assays demonstrated that Hu-IFN-alpha A, -beta, and -omega, but not Hu-IFN-gamma, were able to block binding of 32P-labeled Hu-IFN-alpha A to human cells. These results indicate that Hu-IFN-omega binds to the alpha/beta Receptor.
Gianni Garotta - One of the best experts on this subject based on the ideXlab platform.
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Interaction Between the Components of the Interferon Gamma Receptor Complex
The Journal of biological chemistry, 1995Co-Authors: Serguei V. Kotenko, Jeffry R. Cook, Robert J. Donnelly, Thomas M Mariano, Gianni Garotta, Geetha Muthukumaran, Lara S. Izotova, Brian P. Pollack, Olli Silvennoinen, James N. IhleAbstract:Abstract Interferon γ (IFN-γ) signals through a multimeric Receptor complex consisting of two different chains: the IFN-γ Receptor binding subunit (IFN-γR, IFN-γR1), and a transmembrane accessory factor (AF-1, IFN-γR2) necessary for signal transduction. Using cell lines expressing different cloned components of the IFN-γ Receptor complex, we examined the function of the Receptor components in signal transduction upon IFN-γ treatment. A specific IFN-γR2:IFN-γ cross-linked complex was observed in cells expressing both IFN-γR1 and IFN-γR2 indicating that IFN-γR2 (AF-1) interacts with IFN-γ and is closely associated with IFN-γR1. We show that the intracellular domain of IFN-γR2 is necessary for signaling. Cells coexpressing IFN-γR1 and truncated IFN-γR2, lacking the COOH-terminal 51 amino acids (residues 286-337), or cells expressing IFN-γR1 alone were unresponsive to IFN-γ treatment as measured by MHC class I antigen induction. Jak1, Jak2, and Stat1α were activated, and IFN-γR1 was phosphorylated only in cells expressing both IFN-γR1 and IFN-γR2. Jak2 kinase was shown to associate with the intracellular domain of the IFN-γR2.
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Dissection of the extracellular human interferon gamma Receptor alpha-chain into two immunoglobulin-like domains. Production in an Escherichia coli thioredoxin gene fusion expression system and recognition by neutralizing antibodies.
Biochemistry, 1995Co-Authors: Geoffrey Williams, Michel Aguet, Gianni Garotta, N. Ruegg, A. Birch, C. Weber, K. Hofstadter, John A. Robinson, D. Schlatter, W. HuberAbstract:The extracellular interferon gamma Receptor alpha-chain (IFN gamma R) is believed to comprise two discrete approximately 110 amino acid immunoglobulin-like domains, perhaps similar to those seen in the crystal structure of the extracellular human growth hormone Receptor [De Vos, A. M., Ultsch, M., & Kossiakoff, A. (1992) Science 255, 306-312], a distant relative in the cytokine Receptor superfamily. In accord with this idea, we show that these IFN gamma R immunoglobulin-like domains can be produced separately in a soluble form with a native-like fold. The N-terminal domain (residues 1-108), with a Cys105 to Ser105 mutation, was produced at a high level, in a soluble form, as a thioredoxin-interferon gamma Receptor fragment fusion protein in the cytoplasm of Escherichia coli. Upon extraction, the Receptor Cys60-Cys68 disulfide bond formed spontaneously, to generate a native-like structure directly without the need for refolding. Cleavage of the fusion protein by enterokinase released the Receptor fragment (approximately 12 kDa), which was recognized by several neutralizing antibodies with affinities, measured using surface plasmon resonance technology, that were essentially indistinguishable from those seen with the full length extracellular IFN gamma R produced in eukaryotic cells. Circular dichroism and 1D 1H nuclear magnetic resonance spectra indicated that the Receptor fragment adopts a folded state, with mainly beta-sheet and reverse turn secondary structure. The second membrane-proximal Ig-like domain of the IFN gamma R (residues 90-229) was produced, albeit less efficiently, and characterized in a similar way. The production of these two independently folded proteins provides experimental support for the two domain organization of the IFN gamma R and opens new avenues for structural studies on these Ig-like molecules by NMR and crystallographic methods.
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experimental therapy of systemic lupus erythematosus the treatment of nzb w mice with mouse soluble interferon gamma Receptor inhibits the onset of glomerulonephritis
European Journal of Immunology, 1995Co-Authors: Laurence Ozmen, Michael Fountoulakis, Daniele Roman, Georges Schmid, B Ryffel, Gianni GarottaAbstract:Female NZB/W F1 mice develop an autoimmune disease similar to human systemic lupus erythematosus (SLE), and ultimately die of glomerulonephritis. Starting at the age of 16 weeks NZB/W F1 mice were treated for a period of 19 weeks with soluble Interferon-Gamma Receptor (sIFN-gamma R), anti-IFN-gamma monoclonal antibody (mAb) or IFN-gamma. All mice treated with sIFN-gamma R or anti-IFN-gamma mAb were alive 4 weeks after the treatment was discontinued, whereas 50% of mice died in the placebo groups and 78% of the mice died in the IFN-gamma-treated group. Histologically, there was severe membrano-proliferative glomerulonephritis in IFN-gamma- and placebo-treated mice, and minimal or no mesangioproliferative disease in mice receiving sIFN-gamma R or anti-IFN-gamma mAb. The renal mononuclear infiltrate (T lymphocytes and monocytes), expression of major histocompatibility complex class II antigen and glomerular immunoglobulin and complement deposition were reduced in those mice. These data suggest that an IFN-gamma inhibitor, such as the soluble IFN-gamma R, can be used for SLE therapy in the early stages of the disease.
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Experimental therapy of systemic lupus erythematosus: the treatment of NZB/W mice with mouse soluble Interferon-Gamma Receptor inhibits the onset of glomerulonephritis.
European journal of immunology, 1995Co-Authors: Laurence Ozmen, Michael Fountoulakis, Daniele Roman, Georges Schmid, Ryffel B, Gianni GarottaAbstract:Female NZB/W F1 mice develop an autoimmune disease similar to human systemic lupus erythematosus (SLE), and ultimately die of glomerulonephritis. Starting at the age of 16 weeks NZB/W F1 mice were treated for a period of 19 weeks with soluble Interferon-Gamma Receptor (sIFN-gamma R), anti-IFN-gamma monoclonal antibody (mAb) or IFN-gamma. All mice treated with sIFN-gamma R or anti-IFN-gamma mAb were alive 4 weeks after the treatment was discontinued, whereas 50% of mice died in the placebo groups and 78% of the mice died in the IFN-gamma-treated group. Histologically, there was severe membrano-proliferative glomerulonephritis in IFN-gamma- and placebo-treated mice, and minimal or no mesangioproliferative disease in mice receiving sIFN-gamma R or anti-IFN-gamma mAb. The renal mononuclear infiltrate (T lymphocytes and monocytes), expression of major histocompatibility complex class II antigen and glomerular immunoglobulin and complement deposition were reduced in those mice. These data suggest that an IFN-gamma inhibitor, such as the soluble IFN-gamma R, can be used for SLE therapy in the early stages of the disease.
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Alignment of disulfide bonds of the extracellular domain of the interferon gamma Receptor and investigation of their role in biological activity.
Biochemistry, 1993Co-Authors: Dietrich Stüber, Hans-werner Lahm, Arno Friedlein, Fountoulakis M, Gianni GarottaAbstract:The extracellular ligand binding domain of the human interferon gamma Receptor includes eight cysteine residues forming four disulfide bonds. Only the nonreduced protein binds interferon gamma. We investigated the alignment of the disulfide bonds, using an enzymatically deglycosylated form of a soluble interferon gamma Receptor, produced in baculovirus-infected insect cells. The soluble Receptor was digested with endoproteinase Glu-C and proteinase K, and the proteolytic fragments were characterized by amino acid sequence analysis and mass spectrometry. It was found that four consecutive disulfide bonds are formed between residues Cys60-Cys68, Cys105-Cys150, Cys178-Cys183, and Cys197-Cys218. We also investigated the role of the disulfide bonds in biological activity of the Receptor, using site-directed mutagenesis and by exchanging the cysteine residues for serines. The mutated proteins were expressed in Escherichia coli and analyzed for ligand binding capacity on protein blots. The assays showed that all disulfide bonds are essential for full ligand binding capacity. Double or quadruple mutations at cysteine residues 60 and 68, and residues 178, 183, 197, and 218, respectively, resulted in complete loss of the activity, whereas double mutations at residues 105 and 150, 178 and 183, and 197 and 218, respectively, resulted in a residual activity about 1 order of magnitude lower than that of the wild type. The specific antibodies gamma R38 and gamma R99 detected conformational epitopes stabilized by disulfide bonds involving cysteine residues 60 and 68, and 178 and 183, respectively.
Toshiyuki Masuzawa - One of the best experts on this subject based on the ideXlab platform.
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Urinary evaluation of the balance between soluble Interferon-Gamma Receptor (IFN-γR1) and interleukin-4 Receptor (IL-4Rα)
International Immunopharmacology, 2008Co-Authors: Yoshihiro Okamoto, Takuhito Nagai, Yoshimitsu Gotoh, Naoya Fujita, Takashi Fukui, Izumi Nakajo, Kyoko Seta, Toshiyuki MasuzawaAbstract:To elucidate the usefulness of the simultaneous analysis of multiple kinds of soluble cytokine Receptors in urine specimens, we determined the levels of both the soluble Interferon-Gamma Receptor α chain (sIFN-γR1, Th1-type cytokine Receptor) and the soluble interleukin 4-Receptor α chain (sIL-4Rα, Th2-type cytokine Receptor) in the urine of healthy subjects as reference values and preliminarily applied this method to evaluate patients with diarrhea positive (D+) hemolytic uremic syndrome (HUS) as the diagnostic parameters. The urinary sIFN-γR levels of children were significantly lower than those of adults (p < 0.01, n = 107). On the other hand, there was no significant difference between the urine sIL-4R levels of adults and children. Statistical correlation between sIFN-γR and sIL-4R values was not observed (p = 0.705). On the day of onset of HUS, the urine sIFN-γR levels of the patients (n = 6) with HUS were higher than those of the healthy control group (n = 67) (p < 0.01); however, there was no significant difference in the sIL-4R levels between both groups. The urine evaluation of the balance between the soluble cytokine Receptors might be informative for the immune states of HUS patients.
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Urinary evaluation of the balance between soluble Interferon-Gamma Receptor (IFN-gammaR1) and interleukin-4 Receptor (IL-4Ralpha).
International immunopharmacology, 2008Co-Authors: Yoshihiro Okamoto, Takuhito Nagai, Yoshimitsu Gotoh, Naoya Fujita, Takashi Fukui, Izumi Nakajo, Kyoko Seta, Toshiyuki MasuzawaAbstract:To elucidate the usefulness of the simultaneous analysis of multiple kinds of soluble cytokine Receptors in urine specimens, we determined the levels of both the soluble Interferon-Gamma Receptor alpha chain (sIFN-gammaR1, Th1-type cytokine Receptor) and the soluble interleukin 4-Receptor alpha chain (sIL-4Ralpha, Th2-type cytokine Receptor) in the urine of healthy subjects as reference values and preliminarily applied this method to evaluate patients with diarrhea positive (D+) hemolytic uremic syndrome (HUS) as the diagnostic parameters. The urinary sIFN-gammaR levels of children were significantly lower than those of adults (p < 0.01, n = 107). On the other hand, there was no significant difference between the urine sIL-4R levels of adults and children. Statistical correlation between sIFN-gammaR and sIL-4R values was not observed (p = 0.705). On the day of onset of HUS, the urine sIFN-gammaR levels of the patients (n = 6) with HUS were higher than those of the healthy control group (n = 67) (p < 0.01); however, there was no significant difference in the sIL-4R levels between both groups. The urine evaluation of the balance between the soluble cytokine Receptors might be informative for the immune states of HUS patients.
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Age-Dependent Decrease in Serum Soluble Interferon-Gamma Receptor (sIFN-γR) in Healthy Japanese Individuals; Population Study of Serum sIFN-γR Level in Japanese
Journal of immunoassay & immunochemistry, 2008Co-Authors: Yoshihiro Okamoto, Takuhito Nagai, Yoshimitsu Gotoh, Naoya Fujita, Takashi Fukui, Izumi Nakajo, Kyoko Seta, Toshiyuki MasuzawaAbstract:Abstract We planned to investigate the clinical significance of serum soluble Interferon-Gamma Receptor (sIFN-γR) level in pediatric patients. The diagnostic application of the measurement of serum sIFN-γR level depends critically on the control value. However, there is no information of the control value of serum sIFN-γR for children. In the present study, we determined the serum sIFN-γR level of healthy Japanese children using an ELISA. The serum sIFN-γR level of children (0–14 years old) was significantly higher than that of adults (over 15 years old) (p
Michael Fountoulakis - One of the best experts on this subject based on the ideXlab platform.
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experimental therapy of systemic lupus erythematosus the treatment of nzb w mice with mouse soluble interferon gamma Receptor inhibits the onset of glomerulonephritis
European Journal of Immunology, 1995Co-Authors: Laurence Ozmen, Michael Fountoulakis, Daniele Roman, Georges Schmid, B Ryffel, Gianni GarottaAbstract:Female NZB/W F1 mice develop an autoimmune disease similar to human systemic lupus erythematosus (SLE), and ultimately die of glomerulonephritis. Starting at the age of 16 weeks NZB/W F1 mice were treated for a period of 19 weeks with soluble Interferon-Gamma Receptor (sIFN-gamma R), anti-IFN-gamma monoclonal antibody (mAb) or IFN-gamma. All mice treated with sIFN-gamma R or anti-IFN-gamma mAb were alive 4 weeks after the treatment was discontinued, whereas 50% of mice died in the placebo groups and 78% of the mice died in the IFN-gamma-treated group. Histologically, there was severe membrano-proliferative glomerulonephritis in IFN-gamma- and placebo-treated mice, and minimal or no mesangioproliferative disease in mice receiving sIFN-gamma R or anti-IFN-gamma mAb. The renal mononuclear infiltrate (T lymphocytes and monocytes), expression of major histocompatibility complex class II antigen and glomerular immunoglobulin and complement deposition were reduced in those mice. These data suggest that an IFN-gamma inhibitor, such as the soluble IFN-gamma R, can be used for SLE therapy in the early stages of the disease.
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Experimental therapy of systemic lupus erythematosus: the treatment of NZB/W mice with mouse soluble Interferon-Gamma Receptor inhibits the onset of glomerulonephritis.
European journal of immunology, 1995Co-Authors: Laurence Ozmen, Michael Fountoulakis, Daniele Roman, Georges Schmid, Ryffel B, Gianni GarottaAbstract:Female NZB/W F1 mice develop an autoimmune disease similar to human systemic lupus erythematosus (SLE), and ultimately die of glomerulonephritis. Starting at the age of 16 weeks NZB/W F1 mice were treated for a period of 19 weeks with soluble Interferon-Gamma Receptor (sIFN-gamma R), anti-IFN-gamma monoclonal antibody (mAb) or IFN-gamma. All mice treated with sIFN-gamma R or anti-IFN-gamma mAb were alive 4 weeks after the treatment was discontinued, whereas 50% of mice died in the placebo groups and 78% of the mice died in the IFN-gamma-treated group. Histologically, there was severe membrano-proliferative glomerulonephritis in IFN-gamma- and placebo-treated mice, and minimal or no mesangioproliferative disease in mice receiving sIFN-gamma R or anti-IFN-gamma mAb. The renal mononuclear infiltrate (T lymphocytes and monocytes), expression of major histocompatibility complex class II antigen and glomerular immunoglobulin and complement deposition were reduced in those mice. These data suggest that an IFN-gamma inhibitor, such as the soluble IFN-gamma R, can be used for SLE therapy in the early stages of the disease.
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Structural analysis and localization of the carbohydrate moieties of a soluble human interferon gamma Receptor produced in baculovirus-infected insect cells.
Protein science : a publication of the Protein Society, 1994Co-Authors: Michael Manneberg, Arno Friedlein, Hans-werner Lahm, Holger Kurth, Michael FountoulakisAbstract:A soluble form of the human interferon gamma Receptor that is required for the identification of interferon gamma antagonists was expressed in baculovirus-infected insect cells. The protein carried N-linked carbohydrate and showed a heterogeneity on denaturing polyacrylamide gels. We investigated the utilization of the potential sites for N-linked glycosylation and the structure of the carbohydrate moieties of this soluble Receptor. Amino acid sequence analysis and ion spray mass spectrometry revealed that of the five potential sites for N-linked glycosylation, Asn17 and Asn69 were always utilized, whereas Asn62 and Asn162 were utilized in approximately one-third of the protein population. Asn223 was never found to be glycosylated. The soluble Receptor was treated with N-glycosidase F and the oligosaccharides released were analyzed by matrix-assisted laser desorption mass spectrometry, which showed that the protein carried six types of short carbohydrate chains. The predominant species was a hexasaccharide of molecular mass 1,039, containing a fucose subunit linked to the proximal N-acetylglucosamine residue: [formula: see text]
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Unfolding intermediates of the extracellular domain of the interferon gamma Receptor.
The Journal of biological chemistry, 1992Co-Authors: Michael FountoulakisAbstract:Reduction of proteins which require disulfide bonds to be stable in the folded state is accompanied by step-wise unfolding. A soluble human interferon gamma Receptor produced in Escherichia coli was used to investigate the kinetics of formation of unfolding intermediates. The protein includes 8 cysteine residues forming four disulfide bonds. It was reduced by using either dithiothreitol or the thioredoxin reduction system. Reduction with dithiothreitol resulted in formation of mainly four monomeric unfolding species as visualized by sodium dodecyl sulfate-polyacrylamide gels. The enzymatically catalyzed reaction produced only small amounts of two monomeric products and mostly delivered oligomeric and polymeric forms. In both cases, the ligand binding capacity of the Receptor was significantly reduced immediately after appearance of the first intermediate. The intermediates involved interchange of disulfide bonds and did not show ligand binding capacity. Some of them were recognized by specific antibodies which detect conformational epitopes on the native interferon gamma Receptor. On the basis of the antibody binding, a preliminary characterization of the formed intermediates was attempted. When the soluble Receptor was reduced in the presence of denaturing agents, the reduction products were different from the unfolding intermediates generated in the absence of denaturants.
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A 25-kDa stretch of the extracellular domain of the human interferon gamma Receptor is required for full ligand binding capacity.
Journal of Biological Chemistry, 1991Co-Authors: Michael Fountoulakis, A Maris, Hans-werner Lahm, Arno Friedlein, Michael Manneberg, D Stueber, Gianni GarottaAbstract:Abstract We investigated which is the shortest fragment of the interferon gamma Receptor with ligand binding capacity. A recombinant soluble interferon gamma Receptor produced in Escherichia coli was subjected to controlled digestion with several proteolytic enzymes. The fragments generated were assayed by four approaches for interferon gamma binding. A 25-kDa polypeptide comprising residues 6-227 of the mature protein was produced by sequential digestion with trypsin and proteinase K. It was identified as the shortest Receptor domain with full interferon gamma binding capacity as judged by ligand blots. The proteolytic fragments were further tested for ligand binding by interferon gamma affinity chromatography. A 15-kDa polypeptide comprising amino acids 94-227 produced by digestion with endoproteinase Glu-C was found to bind with low affinity to immobilized interferon gamma. This fragment, which does not show ligand binding capacity on protein blots, was immunoprecipitated as a complex with interferon gamma by anti-interferon gamma antibodies. It also competed for the binding of radiolabeled interferon gamma to the cell surface Receptor when it was assayed as a mixture of the proteolytic products, but not after separation from the cleaved rest of the molecule. The 15-kDa polypeptide probably carries the ligand-binding domain or part of it, but it lacks sequences essential for full interferon gamma binding capacity. The stretch between amino acids 6 and 21 which does not include any disulfide bonds seems to be essential for the Receptor to show full activity. The digestion with endoproteinase Glu-C revealed that cysteine residues 60 and 68 of the interferon gamma Receptor form a disulfide bond.
Yoshihiro Okamoto - One of the best experts on this subject based on the ideXlab platform.
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Urinary evaluation of the balance between soluble Interferon-Gamma Receptor (IFN-γR1) and interleukin-4 Receptor (IL-4Rα)
International Immunopharmacology, 2008Co-Authors: Yoshihiro Okamoto, Takuhito Nagai, Yoshimitsu Gotoh, Naoya Fujita, Takashi Fukui, Izumi Nakajo, Kyoko Seta, Toshiyuki MasuzawaAbstract:To elucidate the usefulness of the simultaneous analysis of multiple kinds of soluble cytokine Receptors in urine specimens, we determined the levels of both the soluble Interferon-Gamma Receptor α chain (sIFN-γR1, Th1-type cytokine Receptor) and the soluble interleukin 4-Receptor α chain (sIL-4Rα, Th2-type cytokine Receptor) in the urine of healthy subjects as reference values and preliminarily applied this method to evaluate patients with diarrhea positive (D+) hemolytic uremic syndrome (HUS) as the diagnostic parameters. The urinary sIFN-γR levels of children were significantly lower than those of adults (p < 0.01, n = 107). On the other hand, there was no significant difference between the urine sIL-4R levels of adults and children. Statistical correlation between sIFN-γR and sIL-4R values was not observed (p = 0.705). On the day of onset of HUS, the urine sIFN-γR levels of the patients (n = 6) with HUS were higher than those of the healthy control group (n = 67) (p < 0.01); however, there was no significant difference in the sIL-4R levels between both groups. The urine evaluation of the balance between the soluble cytokine Receptors might be informative for the immune states of HUS patients.
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Urinary evaluation of the balance between soluble Interferon-Gamma Receptor (IFN-gammaR1) and interleukin-4 Receptor (IL-4Ralpha).
International immunopharmacology, 2008Co-Authors: Yoshihiro Okamoto, Takuhito Nagai, Yoshimitsu Gotoh, Naoya Fujita, Takashi Fukui, Izumi Nakajo, Kyoko Seta, Toshiyuki MasuzawaAbstract:To elucidate the usefulness of the simultaneous analysis of multiple kinds of soluble cytokine Receptors in urine specimens, we determined the levels of both the soluble Interferon-Gamma Receptor alpha chain (sIFN-gammaR1, Th1-type cytokine Receptor) and the soluble interleukin 4-Receptor alpha chain (sIL-4Ralpha, Th2-type cytokine Receptor) in the urine of healthy subjects as reference values and preliminarily applied this method to evaluate patients with diarrhea positive (D+) hemolytic uremic syndrome (HUS) as the diagnostic parameters. The urinary sIFN-gammaR levels of children were significantly lower than those of adults (p < 0.01, n = 107). On the other hand, there was no significant difference between the urine sIL-4R levels of adults and children. Statistical correlation between sIFN-gammaR and sIL-4R values was not observed (p = 0.705). On the day of onset of HUS, the urine sIFN-gammaR levels of the patients (n = 6) with HUS were higher than those of the healthy control group (n = 67) (p < 0.01); however, there was no significant difference in the sIL-4R levels between both groups. The urine evaluation of the balance between the soluble cytokine Receptors might be informative for the immune states of HUS patients.
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Age-Dependent Decrease in Serum Soluble Interferon-Gamma Receptor (sIFN-γR) in Healthy Japanese Individuals; Population Study of Serum sIFN-γR Level in Japanese
Journal of immunoassay & immunochemistry, 2008Co-Authors: Yoshihiro Okamoto, Takuhito Nagai, Yoshimitsu Gotoh, Naoya Fujita, Takashi Fukui, Izumi Nakajo, Kyoko Seta, Toshiyuki MasuzawaAbstract:Abstract We planned to investigate the clinical significance of serum soluble Interferon-Gamma Receptor (sIFN-γR) level in pediatric patients. The diagnostic application of the measurement of serum sIFN-γR level depends critically on the control value. However, there is no information of the control value of serum sIFN-γR for children. In the present study, we determined the serum sIFN-γR level of healthy Japanese children using an ELISA. The serum sIFN-γR level of children (0–14 years old) was significantly higher than that of adults (over 15 years old) (p