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Hollander MJ, Malaker SA, Riley NM, Perez I, Abney NM, Gray MA, Maxson JE, Cochran JR, Bertozzi CR. Mutational screens highlight glycosylation as a modulator of colony-stimulating factor 3 receptor (CSF3R) activity. J Biol Chem 2023; 299:104755. [PMID: 37116708 PMCID: PMC10245049 DOI: 10.1016/j.jbc.2023.104755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 04/21/2023] [Accepted: 04/23/2023] [Indexed: 04/30/2023] Open
Abstract
The colony-stimulating factor 3 receptor (CSF3R) controls the growth of neutrophils, the most abundant type of white blood cell. In healthy neutrophils, signaling is dependent on CSF3R binding to its ligand, CSF3. A single amino acid mutation in CSF3R, T618I, instead allows for constitutive, ligand-independent cell growth and leads to a rare type of cancer called chronic neutrophilic leukemia. However, the disease mechanism is not well understood. Here, we investigated why this threonine to isoleucine substitution is the predominant mutation in chronic neutrophilic leukemia and how it leads to uncontrolled neutrophil growth. Using protein domain mapping, we demonstrated that the single CSF3R domain containing residue 618 is sufficient for ligand-independent activity. We then applied an unbiased mutational screening strategy focused on this domain and found that activating mutations are enriched at sites normally occupied by asparagine, threonine, and serine residues-the three amino acids which are commonly glycosylated. We confirmed glycosylation at multiple CSF3R residues by mass spectrometry, including the presence of GalNAc and Gal-GalNAc glycans at WT threonine 618. Using the same approach applied to other cell surface receptors, we identified an activating mutation, S489F, in the interleukin-31 receptor alpha chain. Combined, these results suggest a role for glycosylated hotspot residues in regulating receptor signaling, mutation of which can lead to ligand-independent, uncontrolled activity and human disease.
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Affiliation(s)
- Michael J Hollander
- Department of Bioengineering, Stanford University, Stanford, California, USA; Department of Chemistry and Sarafan ChEM-H, Stanford University, Stanford, California, USA
| | - Stacy A Malaker
- Department of Chemistry and Sarafan ChEM-H, Stanford University, Stanford, California, USA
| | - Nicholas M Riley
- Department of Chemistry and Sarafan ChEM-H, Stanford University, Stanford, California, USA
| | - Idalia Perez
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Nayla M Abney
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Melissa A Gray
- Department of Chemistry and Sarafan ChEM-H, Stanford University, Stanford, California, USA
| | - Julia E Maxson
- Knight Cancer Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Jennifer R Cochran
- Department of Bioengineering, Stanford University, Stanford, California, USA; Department of Chemical Engineering, Stanford University, Stanford, California, USA.
| | - Carolyn R Bertozzi
- Department of Chemistry and Sarafan ChEM-H, Stanford University, Stanford, California, USA; Howard Hughes Medical Institute, Stanford, California, USA.
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Sun S, Fulati W, Shen L, Wu M, Huang Z, Qian W, Chen P, Hu Y, Chen M, Xu Y, Zhang H, Ma J, Xie Y. Maintenance regimen of GM-CSF with rituximab and lenalidomide improves survival in high-risk B-cell lymphoma by modulating natural killer cells. Cancer Med 2023. [PMID: 37081754 DOI: 10.1002/cam4.5969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 04/03/2023] [Accepted: 04/06/2023] [Indexed: 04/22/2023] Open
Abstract
BACKGROUND The treatment of high-risk B-cell lymphoma (BCL) remains a challenge, especially in the elderly. METHODS A total of 83 patients (median age 65 years), who have achieved a complete response after induction therapy, were divided into two groups: R2 + GM-CSF regimen (lenalidomide, rituximab, granulocyte-macrophage colony-stimulating factor [GM-CSF]) as maintenance therapy (n = 39) and observation (n = 44). The efficacy of the R2 + GM-CSF regimen as maintenance in patient with high-risk BCL was analyzed and compared with observation. RESULTS The number of natural killer cells in patients increased after R2 + GM-CSF regimen administration (0.131 × 109 /L vs. 0.061 × 109 /L, p = 0.0244). Patients receiving the R2 + GM-CSF regimen as maintenance therapy had longer remission (duration of response: 18.9 vs. 11.3 months, p = 0.001), and longer progression-free survival (not reached (NR) vs. 31.7 months, p = 0.037), and overall survival (OS) (NR vs. NR, p = 0.015). The R2 + GM-CSF regimen was safe and well tolerated. High international prognostic index score (p = 0.012), and high tumor burden (p = 0.005) appeared to be independent prognostic factors for worse PFS. CONCLUSIONS The maintenance therapy of R2 + GM-CSF regimen may improve survival in high-risk BCL patients, which might be modulated by amplification of natural killer cells. The efficacy of the R2 + GM-CSF maintenance regimen has to be further validated in prospective random clinical trials.
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Affiliation(s)
- Shunrong Sun
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Wulipan Fulati
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Lin Shen
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Min Wu
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Zilan Huang
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Wensi Qian
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Pingping Chen
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Yingwei Hu
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Mingyue Chen
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Yu Xu
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Hongdi Zhang
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Jiexian Ma
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
| | - Yanhui Xie
- Department of Hematology, Huadong Hospital Affiliated with Fudan University, Shanghai, China
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Cheng Q, Zhang XN, Zhang L, Chen J, Wang Y, Zhang Y. A Poly-ADP-Ribose Polymer-GCSF Conjugate. Biomacromolecules 2022; 23:5267-5272. [PMID: 36350184 PMCID: PMC9772087 DOI: 10.1021/acs.biomac.2c01090] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Poly-ADP-ribose (PAR) is a naturally occurring form of polymers synthesized through enzymatic reactions catalyzed by poly(ADP-ribose) polymerases (PARPs). It is known for regulating various important cellular signaling pathways and processes. As a water soluble and biocompatible type of polymer, PAR may hold promise for safe and efficient delivery of therapeutics. To explore the therapeutic potential of PAR polymers, we herein generate PAR polymers conjugated with human granulocyte colony-stimulating factor (GCSF) protein by harnessing human PARP1-catalyzed auto-poly-ADP-ribosylation and a clickable analogue of nicotinamide adenine dinucleotide (NAD+). The resulting PAR polymer-based conjugate with multivalent GCSF ligands exhibits a potent cell proliferative activity. Notably, mice treated with a single dose of the PAR polymer-GCSF conjugate show sustained high levels of neutrophil in blood for 11 days, demonstrating excellent in vivo efficacy. Functionalized PAR polymers may provide new scaffolds for conjugating with therapeutic proteins or peptides toward improved pharmacological activities.
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Affiliation(s)
- Qinqin Cheng
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90089
| | - Xiao-Nan Zhang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90089
| | - Lei Zhang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90089
| | - Jingwen Chen
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90089
| | - Yiling Wang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90089
| | - Yong Zhang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90089, Department of Chemistry, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, CA 90089, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, Research Center for Liver Diseases, University of Southern California, Los Angeles, CA 90089,
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4
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Cao XH, Hong Y, Yu X, Xu LP, Zhang XH, Wang Y, Liu KY, Huang XJ, Chang YJ, Zhao XY, Zhao XS. Donor CSF3R with the rs3917980A/G or G/G genotype is correlated with better leukemia-free survival after allogenic hematopoietic stem cell transplantation. Genes Immun 2022; 23:166-174. [PMID: 35821521 DOI: 10.1038/s41435-022-00177-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 06/09/2022] [Accepted: 06/17/2022] [Indexed: 11/09/2022]
Abstract
Polymorphisms in the granulocyte colony-stimulating factor receptor gene (GCSFR, CSF3R) have been reported to be associated with peripheral blood stem cell enrichment and hematological diseases. The aim of our study was to investigate the effects of donor CSF3R allelic polymorphisms on the outcomes of allogeneic stem cell transplantation. A total of 273 patients who were diagnosed with hematological diseases and treated with allogeneic hematopoietic stem cell transplantation(allo-HSCT) were enrolled in this study. Single-nucleotide polymorphisms in CSF3R were genotyped by targeted next-generation sequencing. There were six types of CSF3R genotypes with percentages over 1%. LFS and OS analyses showed that recipients receiving grafts from healthy donors with a rs3917980 G/G or A/G genotype had higher LFS rates than those receiving grafts from donors carrying a rs22754272 T/C genotype and the double-negative group (p = 0.036). Univariate cox analysis showed that donor CSF3R with the rs2275472 T/C genotype was associated with higher transplantation-related mortality (TRM) rates (HR = 2.853, 95% CI: 1.405-5.792, p = 0.00371) and lower rates of leukemia-free survival (LFS) (HR = 1.846; 95% CI: 1.018-3.347, p = 0.0435). In addition, donor CSF3R with the rs3917980G/G or A/G genotype was associated with better overall survival (OS) rates (HR = 0.560, 95% CI: 0.3162-0.9916, p = 0.047) and lower TRM rates (HR = 0.497, 95% CI: 0.2628-0.9397, p = 0.0315). Furthermore, multivariate cox analysis found that rs2275472 T/C genotype was an independent risk factors for TRM rates (HR = 3.210, 95% CI: 1.573-6.55, p = 0.001), while no statistical difference was found between rs3917980G/G or A/G genotype and clinical outcomes. Our findings demonstrate the important prognostic value of genetic variations in donor CSF3R to predict clinical outcomes in patients undergoing allo-HSCT.
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Affiliation(s)
- Xun-Hong Cao
- Peking University People's Hospital, Peking University Institute of Hematology, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, National Clinical Research Center for Hematologic Disease, Beijing, China
| | - Yan Hong
- Department of Hematology, The First Affiliated Hospital of Xiamen University and Institute of Hematology, School of Medicine, Xiamen University, Xiamen, China
| | - Xingxing Yu
- Department of Hematology, The First Affiliated Hospital of Xiamen University and Institute of Hematology, School of Medicine, Xiamen University, Xiamen, China
| | - Lan-Ping Xu
- Peking University People's Hospital, Peking University Institute of Hematology, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, National Clinical Research Center for Hematologic Disease, Beijing, China
| | - Xiao-Hui Zhang
- Peking University People's Hospital, Peking University Institute of Hematology, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, National Clinical Research Center for Hematologic Disease, Beijing, China
| | - Yu Wang
- Peking University People's Hospital, Peking University Institute of Hematology, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, National Clinical Research Center for Hematologic Disease, Beijing, China
| | - Kai-Yan Liu
- Peking University People's Hospital, Peking University Institute of Hematology, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, National Clinical Research Center for Hematologic Disease, Beijing, China
| | - Xiao-Jun Huang
- Peking University People's Hospital, Peking University Institute of Hematology, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, National Clinical Research Center for Hematologic Disease, Beijing, China
| | - Ying-Jun Chang
- Peking University People's Hospital, Peking University Institute of Hematology, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, National Clinical Research Center for Hematologic Disease, Beijing, China
| | - Xiang-Yu Zhao
- Peking University People's Hospital, Peking University Institute of Hematology, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, National Clinical Research Center for Hematologic Disease, Beijing, China.
| | - Xiao-Su Zhao
- Peking University People's Hospital, Peking University Institute of Hematology, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, National Clinical Research Center for Hematologic Disease, Beijing, China. .,Collaborative Innovation Center of Hematology, Peking University, Beijing, China.
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5
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Mickiene G, Dalgėdienė I, Zvirblis G, Dapkunas Z, Plikusiene I, Buzavaite-Verteliene E, Balevičius Z, Rukšėnaitė A, Pleckaityte M. Human granulocyte-colony stimulating factor (G-CSF)/stem cell factor (SCF) fusion proteins: design, characterization and activity. PeerJ 2020; 8:e9788. [PMID: 32884863 PMCID: PMC7444511 DOI: 10.7717/peerj.9788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 07/31/2020] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Stem cell factor (SCF) and granulocyte-colony stimulating factor (G-CSF) are well-characterized vital hematopoietic growth factors that regulate hematopoiesis. G-CSF and SCF synergistically exhibit a stimulatory effect on hematopoietic progenitors. The combination of G-CSF and SCF has been used for mobilization of peripheral blood progenitor cells in cancer and non-cancerous conditions. To overcome challenges connected with the administration of two cytokines, we developed two fusion proteins composed of human SCF and human G-CSF interspaced by an alpha-helix-forming peptide linker. METHODS The recombinant proteins SCF-Lα-GCSF and GCSF-Lα-SCF were purified in three steps using an ion-exchange and mixed-mode chromatography. The purity and quantity of the proteins after each stage of purification was assessed using RP-HPLC, SDS-PAGE, and the Bradford assays. Purified proteins were identified using high-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS) and the Western blot analyses. The molecular weight was determined by size exclusion HPLC (SE-HPLC). The activity of heterodimers was assessed using cell proliferation assays in vitro. The capacity of recombinant fusion proteins to stimulate the increase of the absolute neutrophil count in rats was determined in vivo. The binding kinetics of the proteins to immobilized G-CSF and SCF receptors was measured using total internal reflection ellipsometry and evaluated by a standard Langmuir kinetics model. RESULTS The novel SCF-Lα-GCSF and GCSF-Lα-SCF proteins were synthesized in Escherichia coli. The purity of the heterodimers reached >90% as determined by RP-HPLC. The identity of the proteins was confirmed using the Western blot and HPLC/ESI-MS assays. An array of multimeric forms, non-covalently associated dimers or trimers were detected in the protein preparations by SE-HPLC. Each protein induced a dose-dependent proliferative response on the cell lines. At equimolar concentration, the heterodimers retain 70-140% of the SCF monomer activity (p ≤ 0.01) in promoting the M-07e cells proliferation. The G-CSF moiety in GCSF-Lα-SCF retained 15% (p ≤ 0.0001) and in SCF-Lα-GCSF retained 34% (p ≤ 0.01) of the monomeric G-CSF activity in stimulating the growth of G-NFS-60 cells. The obtained results were in good agreement with the binding data of each moiety in the fusion proteins to their respective receptors. The increase in the absolute neutrophil count in rats caused by the SCF-Lα-GCSF protein corresponded to the increase induced by a mixture of SCF and G-CSF.
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Affiliation(s)
- Gitana Mickiene
- Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
- Profarma UAB, Vilnius, Lithuania
| | - Indrė Dalgėdienė
- Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
| | | | - Zilvinas Dapkunas
- Institute of Biotechnology, Vilnius University, Vilnius, Lithuania
- Profarma UAB, Vilnius, Lithuania
| | - Ieva Plikusiene
- Department of Physical Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Vilnius, Lithuania
| | - Ernesta Buzavaite-Verteliene
- Plasmonics and Nanophotonics Laboratory, Department of Laser Technology, Center for Physical Sciences and Technology, Vilnius, Lithuania
| | - Zigmas Balevičius
- Plasmonics and Nanophotonics Laboratory, Department of Laser Technology, Center for Physical Sciences and Technology, Vilnius, Lithuania
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7
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Arai S, Shibazaki C, Adachi M, Honjo E, Tamada T, Maeda Y, Tahara T, Kato T, Miyazaki H, Blaber M, Kuroki R. An insight into the thermodynamic characteristics of human thrombopoietin complexation with TN1 antibody. Protein Sci 2016; 25:1786-96. [PMID: 27419667 PMCID: PMC5029525 DOI: 10.1002/pro.2985] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 07/12/2016] [Accepted: 07/13/2016] [Indexed: 11/10/2022]
Abstract
Human thrombopoietin (hTPO) primarily stimulates megakaryocytopoiesis and platelet production and is neutralized by the mouse TN1 antibody. The thermodynamic characteristics of TN1 antibody-hTPO complexation were analyzed by isothermal titration calorimetry (ITC) using an antigen-binding fragment (Fab) derived from the TN1 antibody (TN1-Fab). To clarify the mechanism by which hTPO is recognized by TN1-Fab the conformation of free TN1-Fab was determined to a resolution of 2.0 Å using X-ray crystallography and compared with the hTPO-bound form of TN1-Fab determined by a previous study. This structural comparison revealed that the conformation of TN1-Fab does not substantially change after hTPO binding and a set of 15 water molecules is released from the antigen-binding site (paratope) of TN1-Fab upon hTPO complexation. Interestingly, the heat capacity change (ΔCp) measured by ITC (-1.52 ± 0.05 kJ mol(-1) K(-1) ) differed significantly from calculations based upon the X-ray structure data of the hTPO-bound and unbound forms of TN1-Fab (-1.02 ∼ 0.25 kJ mol(-1) K(-1) ) suggesting that hTPO undergoes an induced-fit conformational change combined with significant desolvation upon TN1-Fab binding. The results shed light on the structural biology associated with neutralizing antibody recognition.
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Affiliation(s)
- Shigeki Arai
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 2-4 Shirakata, Tokai, Ibaraki, 319-1106, Japan.
| | - Chie Shibazaki
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 2-4 Shirakata, Tokai, Ibaraki, 319-1106, Japan
| | - Motoyasu Adachi
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 2-4 Shirakata, Tokai, Ibaraki, 319-1106, Japan
| | - Eijiro Honjo
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 2-4 Shirakata, Tokai, Ibaraki, 319-1106, Japan
| | - Taro Tamada
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 2-4 Shirakata, Tokai, Ibaraki, 319-1106, Japan
| | - Yoshitake Maeda
- Kyowa Hakko Kirin Co. Ltd, 3-6-6 Asahi-Cho, Machida, Tokyo, 194-8533, Japan
| | - Tomoyuki Tahara
- Kyowa Hakko Kirin Co. Ltd, 3-6-6 Asahi-Cho, Machida, Tokyo, 194-8533, Japan
| | - Takashi Kato
- Department of Biology, Faculty of Education and Integrated Arts and Sciences, Waseda University, 2-2 Wakamatsu, Shinjuku, Tokyo, 162-8480, Japan
| | - Hiroshi Miyazaki
- Department of Innovative Drug Discovery and Development, Japan Agency for Medical Research and Development, 1-5-5 Nihonbashi-muromachi, Chuo, Tokyo, 103-0022, Japan
| | - Michael Blaber
- College of Medicine, Florida State University, 1115 West Call Street, Tallahassee, Florida, 32306-4300, USA
| | - Ryota Kuroki
- Quantum Beam Science Research Directorate, National Institutes for Quantum and Radiological Science and Technology, 2-4 Shirakata, Tokai, Ibaraki, 319-1106, Japan
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Mehta HM, Malandra M, Corey SJ. G-CSF and GM-CSF in Neutropenia. THE JOURNAL OF IMMUNOLOGY 2015; 195:1341-9. [PMID: 26254266 DOI: 10.4049/jimmunol.1500861] [Citation(s) in RCA: 229] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
G-CSF and GM-CSF are used widely to promote the production of granulocytes or APCs. The U.S. Food and Drug Administration approved G-CSF (filgrastim) for the treatment of congenital and acquired neutropenias and for mobilization of peripheral hematopoietic progenitor cells for stem cell transplantation. A polyethylene glycol-modified form of G-CSF is approved for the treatment of neutropenias. Clinically significant neutropenia, rendering an individual immunocompromised, occurs when their number is <1500/μl. Current guidelines recommend their use when the risk for febrile neutropenia is >20%. GM-CSF (sargramostim) is approved for neutropenia associated with stem cell transplantation. Because of its promotion of APC function, GM-CSF is being evaluated as an immunostimulatory adjuvant in a number of clinical trials. More than 20 million persons have benefited worldwide, and >$5 billion in sales occur annually in the United States.
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Affiliation(s)
- Hrishikesh M Mehta
- Division of Hematology, Oncology and Stem Cell Transplantation, Department of Pediatrics, Ann and Robert H. Lurie Children's Hospital of Chicago and Robert H. Lurie Comprehensive Cancer Center, Chicago, IL 60611
| | - Michael Malandra
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, IL 60611; and
| | - Seth J Corey
- Division of Hematology, Oncology and Stem Cell Transplantation, Department of Pediatrics, Ann and Robert H. Lurie Children's Hospital of Chicago and Robert H. Lurie Comprehensive Cancer Center, Chicago, IL 60611; Department of Cell and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
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9
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Do BH, Ryu HB, Hoang P, Koo BK, Choe H. Soluble prokaryotic overexpression and purification of bioactive human granulocyte colony-stimulating factor by maltose binding protein and protein disulfide isomerase. PLoS One 2014; 9:e89906. [PMID: 24594699 PMCID: PMC3940694 DOI: 10.1371/journal.pone.0089906] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 01/24/2014] [Indexed: 01/17/2023] Open
Abstract
Human granulocyte colony-stimulating factor (hGCSF), a neutrophil-promoting cytokine, is an effective therapeutic agent for neutropenia patients who have undergone several cancer treatments. Efficient production of hGCSF using E. coli is challenging because the hormone tends to aggregate and forms inclusion bodies. This study examined the ability of seven different N-terminal fusion tags to increase expression of soluble hGCSF in E. coli. Four tag proteins, namely maltose-binding protein (MBP), N-utilization substance protein A, protein disulfide isomerase (PDI), and the b'a' domain of PDI (PDIb'a'), increased the solubility of hGCSF under normal conditions. Lowering the expression temperature from 30°C to 18°C also increased the solubility of thioredoxin-tagged and glutathione S-transferase-tagged hGCSF. By contrast, hexahistidine-tagged hGCSF was insoluble at both temperatures. Simple conventional chromatographic methods were used to purify hGCSF from the overexpressed PDIb'a'-hGCSF and MBP-hGCSF proteins. In total, 11.3 mg or 10.2 mg of pure hGCSF were obtained from 500 mL cultures of E. coli expressing PDIb'a'-hGCSF or MBP-hGCSF, respectively. SDS-PAGE analysis and silver staining confirmed high purity of the isolated hGCSF proteins, and the endotoxin levels were less than 0.05 EU/µg of protein. Subsequently, the bioactivity of the purified hGCSF proteins similar to that of the commercially available hGCSF was confirmed using the mouse M-NFS-60 myelogenous leukemia cell line. The EC50s of the cell proliferation dose-response curves for hGCSF proteins purified from MBP-hGCSF and PDIb'a'-hGCSF were 2.83±0.31 pM, and 3.38±0.41 pM, respectively. In summary, this study describes an efficient method for the soluble overexpression and purification of bioactive hGCSF in E. coli.
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Affiliation(s)
- Bich Hang Do
- Department of Physiology and Biomedical Institute of Technology, University of Ulsan College of Medicine, Seoul, Korea
| | - Han-Bong Ryu
- Department of Physiology and Biomedical Institute of Technology, University of Ulsan College of Medicine, Seoul, Korea
| | - Phuong Hoang
- Department of Physiology and Biomedical Institute of Technology, University of Ulsan College of Medicine, Seoul, Korea
| | - Bon-Kyung Koo
- Department of Physiology and Biomedical Institute of Technology, University of Ulsan College of Medicine, Seoul, Korea
| | - Han Choe
- Department of Physiology and Biomedical Institute of Technology, University of Ulsan College of Medicine, Seoul, Korea
- * E-mail:
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10
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Mehta HM, Futami M, Glaubach T, Lee DW, Andolina JR, Yang Q, Whichard Z, Quinn M, Lu HF, Kao WM, Przychodzen B, Sarkar CA, Minella A, Maciejewski JP, Corey SJ. Alternatively spliced, truncated GCSF receptor promotes leukemogenic properties and sensitivity to JAK inhibition. Leukemia 2013; 28:1041-51. [PMID: 24170028 DOI: 10.1038/leu.2013.321] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 08/06/2013] [Accepted: 09/18/2013] [Indexed: 12/25/2022]
Abstract
Granulocyte colony-stimulating factor (GCSF) drives the production of myeloid progenitor and precursor cells toward neutrophils via the GCSF receptor (GCSFR, gene name CSF3R). Children with severe congenital neutropenia chronically receive pharmacologic doses of GCSF, and ∼30% will develop myelodysplasia/acute myeloid leukemia (AML) associated with GCSFR truncation mutations. In addition to mutations, multiple isoforms of CSF3R have also been reported. We found elevated expression of the alternatively spliced isoform, class IV CSF3R in adult myelodysplastic syndrome/AML patients. Aside from its association with monosomy 7 and higher rates of relapse in pediatric AML patients, little is known about the biology of the class IV isoform. We found developmental regulation of CSF3R isoforms with the class IV expression more representative of a progenitor cell stage. Striking differences were found in phosphoprotein signaling involving Janus kinase (JAK)-signal transducer and activator of transcription (STAT) and cell cycle gene expression. Enhanced proliferation by class IV GCSFR was associated with diminished STAT3 and STAT5 activation, yet showed sensitivity to JAK2 inhibitors. Alterations in the C-terminal domain of the GCSFR result in leukemic properties of enhanced growth, impaired differentiation and resistance to apoptosis, suggesting that they can behave as oncogenic drivers, sensitive to JAK2 inhibition.
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Affiliation(s)
- H M Mehta
- Department of Pediatrics (Hematology-Oncology) and Cell and Molecular Biology, Lurie Children's Hospital of Chicago, Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - M Futami
- 1] Department of Pediatrics (Hematology-Oncology) and Cell and Molecular Biology, Lurie Children's Hospital of Chicago, Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA [2] Division of Molecular Therapy, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - T Glaubach
- Department of Pediatrics (Hematology-Oncology) and Cell and Molecular Biology, Lurie Children's Hospital of Chicago, Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - D W Lee
- Pediatric Oncology Branch, National Cancer Institute, Bethesda, MD, USA
| | - J R Andolina
- 1] Department of Pediatrics (Hematology-Oncology) and Cell and Molecular Biology, Lurie Children's Hospital of Chicago, Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA [2] Department of Pediatrics (Hematology-Oncology), University of Rochester School of Medicine, Rochester, NY, USA
| | - Q Yang
- Department of Pediatrics (Hematology-Oncology) and Cell and Molecular Biology, Lurie Children's Hospital of Chicago, Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Z Whichard
- Department of Pediatrics (Hematology-Oncology) and Cell and Molecular Biology, Lurie Children's Hospital of Chicago, Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - M Quinn
- Department of Pediatrics (Hematology-Oncology) and Cell and Molecular Biology, Lurie Children's Hospital of Chicago, Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - H F Lu
- Department of Pediatrics (Hematology-Oncology) and Cell and Molecular Biology, Lurie Children's Hospital of Chicago, Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - W M Kao
- Cleveland Clinic, Taussig Cancer Institute, Translational Hematology and Oncology Research, Cleveland, OH, USA
| | - B Przychodzen
- Cleveland Clinic, Taussig Cancer Institute, Translational Hematology and Oncology Research, Cleveland, OH, USA
| | - C A Sarkar
- Department of Biomedical Engineering, University of Minnesota, MN, USA
| | - A Minella
- Department of Medicine, Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - J P Maciejewski
- Cleveland Clinic, Taussig Cancer Institute, Translational Hematology and Oncology Research, Cleveland, OH, USA
| | - S J Corey
- Department of Pediatrics (Hematology-Oncology) and Cell and Molecular Biology, Lurie Children's Hospital of Chicago, Robert H Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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11
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Grünberger A, Lai PK, Blanco MA, Roberts CJ. Coarse-grained modeling of protein second osmotic virial coefficients: sterics and short-ranged attractions. J Phys Chem B 2013; 117:763-70. [PMID: 23245189 DOI: 10.1021/jp308234j] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A series of coarse-grained models, with different levels of structural resolution, were tested to calculate the steric contributions to protein osmotic second virial coefficients (B(22,S)) for proteins ranging from small single-domain molecules to large multidomain molecules, using the recently developed Mayer sampling method. B(22,S) was compared for different levels of coarse-graining: four-beads-per-amino-acid (4bAA), one-bead-per-amino-acid (1bAA), one-sphere-per-domain (1sD), and one-sphere-per-protein (1sP). Values for the 1bAA and 4bAA models were quantitatively indistinguishable for both spherical and nonspherical proteins, and the agreement with values from all-atom models improved with increasing protein size, making the CG approach attractive for large proteins of biotechnological interest. Interestingly, in the absence of detailed structural information, the hydrodynamic radius (R(h)) along with a simple 1sP approximation provided reasonably accurate values for B(22,S) for both globular and highly asymmetric protein structures, while other 1sP approximations gave poorer agreement; this helps to justify the currently empirical practice of estimating B(22,S) from R(h) for large proteins such as antibodies. The results also indicate that either 1bAA or 4bAA CG models may be good starting points for incorporating short-range attractions. Comparison of gD-crystallin B(22) values including both sterics and short-range attractions shows that 1bAA and 4bAA models give equivalent results when properly scaled to account for differences in the number of surface beads in the two CG descriptions. This provides a basis for future work that will also incorporate long-ranged electrostatic attractions and repulsions.
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Affiliation(s)
- Alexander Grünberger
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA
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12
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Correlation of liquid chromatographic and biological assay for potency assessment of filgrastim and related impurities. J Pharm Biomed Anal 2010; 53:262-8. [DOI: 10.1016/j.jpba.2010.02.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 02/02/2010] [Accepted: 02/04/2010] [Indexed: 11/22/2022]
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13
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Arakawa T, Wen J. Size-exclusion chromatography with on-line light scattering. ACTA ACUST UNITED AC 2008; Chapter 20:Unit 20.6. [PMID: 18429161 DOI: 10.1002/0471140864.ps2006s25] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This unit describes the use of size-exclusion chromatography with on-line light scattering, UV absorbance, and refractive index detectors (SEC-LS/UV/RI) to determine: (a) the molecular weight of simple proteins containing no carbohydrates, (b) the molecular weight of glycoproteins, and (c), most importantly, the molecular weight and stoichiometry of protein-protein complexes or protein-carbohydrate complexes. Multiangle light scattering is also discussed.
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Affiliation(s)
- T Arakawa
- Alliance Protein Laboratories, Inc., Thousand Oaks, California, USA
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14
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15
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Yu P, Zhang G, Bi J, Lu X, Wang Y, Su Z. Facile purification of mono-PEGylated interleukin-1 receptor antagonist and its characterization with multi-angle laser light scattering. Process Biochem 2007. [DOI: 10.1016/j.procbio.2007.03.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Abstract
The production of blood cells is regulated by a number of protein growth factors and cytokines that influence cell survival, proliferation and differentiation. Many of these molecules bind to cell surface receptors, which belong to a family of closely related cytokine receptors that lack intrinsic catalytic activity but are intimately associated with tyrosine kinases of the Janus kinase (JAK) family. Ligand binding induces the activation of JAKs, which sit at the apex of a signalling cascade in which a key role is played by members of the signal transducers and activators of transcription (STAT) group. Congenital deficiencies in JAK-STAT signalling are associated with immunodeficiency states and acquired activating mutations and translocations are involved in the pathophysiology of haematological malignancy. The latter findings have raised hopes that drugs that target aberrant JAK-STAT signalling may be useful for the treatment of human disease.
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Affiliation(s)
- Asim Khwaja
- Department of Haematology, Royal Free and University College Medical School, London, UK.
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17
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Tamada T, Honjo E, Maeda Y, Okamoto T, Ishibashi M, Tokunaga M, Kuroki R. Homodimeric cross-over structure of the human granulocyte colony-stimulating factor (GCSF) receptor signaling complex. Proc Natl Acad Sci U S A 2006; 103:3135-40. [PMID: 16492764 PMCID: PMC1413920 DOI: 10.1073/pnas.0511264103] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A crystal structure of the signaling complex between human granulocyte colony-stimulating factor (GCSF) and a ligand binding region of GCSF receptor (GCSF-R), has been determined to 2.8 A resolution. The GCSF:GCSF-R complex formed a 2:2 stoichiometry by means of a cross-over interaction between the Ig-like domains of GCSF-R and GCSF. The conformation of the complex is quite different from that between human GCSF and the cytokine receptor homologous domain of mouse GCSF-R, but similar to that of the IL-6/gp130 signaling complex. The Ig-like domain cross-over structure necessary for GCSF-R activation is consistent with previously reported thermodynamic and mutational analyses.
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Affiliation(s)
- Taro Tamada
- *Research Group for Molecular Structural Biology, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai, Ibaraki 319-1195, Japan
| | - Eijiro Honjo
- Pharmaceutical Research Laboratory, Kirin Brewery Co. Ltd., 3 Miyahara-cho, Takasaki 370-1295,Japan; and
| | - Yoshitake Maeda
- Pharmaceutical Research Laboratory, Kirin Brewery Co. Ltd., 3 Miyahara-cho, Takasaki 370-1295,Japan; and
| | - Tomoyuki Okamoto
- Pharmaceutical Research Laboratory, Kirin Brewery Co. Ltd., 3 Miyahara-cho, Takasaki 370-1295,Japan; and
| | - Matsujiro Ishibashi
- Laboratory of Applied Microbiology, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065,Japan
| | - Masao Tokunaga
- Laboratory of Applied Microbiology, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065,Japan
| | - Ryota Kuroki
- *Research Group for Molecular Structural Biology, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai, Ibaraki 319-1195, Japan
- To whom correspondence should be addressed. E-mail:
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18
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Druhan LJ, Ai J, Massullo P, Kindwall-Keller T, Ranalli MA, Avalos BR. Novel mechanism of G-CSF refractoriness in patients with severe congenital neutropenia. Blood 2004; 105:584-91. [PMID: 15353486 DOI: 10.1182/blood-2004-07-2613] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Severe congenital neutropenia (SCN) is a rare disease diagnosed at or soon after birth, characterized by a myeloid maturation arrest in the bone marrow, ineffective neutrophil production, and recurrent infections. Most patients respond to treatment with granulocyte colony-stimulating factor (G-CSF), and the majority harbor mutations in the neutrophil elastase gene. In the subset of patients with SCN transforming to acute myeloid leukemia (AML), mutations that truncate the cytoplasmic tail of the G-CSF receptor (G-CSFR) have been detected. Here, we report a novel mutation in the extracellular portion of the G-CSFR within the WSXWS motif in a patient with SCN without AML who was refractory to G-CSF treatment. The mutation affected a single allele and introduced a premature stop codon that deletes the distal extracellular region and the entire transmembrane and cytoplasmic portions of the G-CSFR. Expression of the mutant receptor in either myeloid or lymphoid cells was shown to alter subcellular trafficking of the wild-type (WT) G-CSFR by constitutively heterodimerizing with it. WT/mutant G-CSFR heterodimers appeared to be retained in the endoplasmic reticulum and/or Golgi and accumulate intracellularly. These findings together with 2 previous case reports of extracellular mutations in the G-CSFR in patients with SCN unresponsive to G-CSF suggest a common mechanism underlying G-CSF refractoriness.
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Affiliation(s)
- Lawrence J Druhan
- Bone Marrow Transplant Program, The Ohio State University, Columbus, OH 43210, USA
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19
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Barackman J, Prado I, Karunatilake C, Furuya K. Evaluation of on-line high-performance size-exclusion chromatography, differential refractometry, and multi-angle laser light scattering analysis for the monitoring of the oligomeric state of human immunodeficiency virus vaccine protein antigen. J Chromatogr A 2004; 1043:57-64. [PMID: 15317413 DOI: 10.1016/j.chroma.2004.02.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Chiron has developed a novel mutant form of the human immunodeficiency virus (HIV) envelop protein, o-gp140, that is currently entering Human Phase 1 clinical trials for testing as a prophylactic HIV vaccine. The o-gp140 protein is oligomeric and the quaternary structure is thought to play an important role in its activity as an antigen. As o-gpl40 proceeds through the clinical trial process and prior to marketing approval, analytical methods that are able to demonstrate manufacturing consistency with respect to degree of oligomerization will need to be developed and validated. On-line high-performance size-exclusion chromatography, differential refractometry, and multi-angle laser light scattering analysis (HPSEC-RI-MALLS), a method commonly used to obtain the molar mass of macromolecules based on the Rayleigh-Gans-Debye approximation, was evaluated for this purpose. The results obtained demonstrated intra- and inter-day precisions to be 0.9 and 3.6% R.S.D., respectively. Accuracy was found to be equal to, or better than, 11% when comparing the known molar masses of test proteins to that of the molar masses determined by the method. Additionally, the method compared favorably to orthogonal native polyacrylamide gel electrophoresis and ultracentrifugation analyses. R-factor analysis was used to demonstrate that HPSEC-RI-MALLS is capable of discriminating compositional differences between o-gpl40 test lots. Based on the data presented, HPSEC-RI-MALLS may be a suitable manufacturing control method.
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Affiliation(s)
- John Barackman
- Chiron Analytical Development, Chiron Corporation, Emeryville, CA 94608, USA.
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20
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Mora-Garcia P, Cheng J, Crans-Vargas HN, Countouriotis A, Shankar D, Sakamoto KM. Transcriptional regulators and myelopoiesis: the role of serum response factor and CREB as targets of cytokine signaling. Stem Cells 2003; 21:123-30. [PMID: 12634408 DOI: 10.1634/stemcells.21-2-123] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hematopoiesis is a complex process in which mature myeloid and lymphoid cells are produced from a small population of pluripotent stem cells within the bone marrow. Blood cell formation occurs, in part, by progenitor cell exposure to humoral growth regulators, known as hematopoietic cytokines, as well as by the regulated expression of genes by transcription factors. In this paper, we review two important nuclear proteins, the serum response factor and the cyclic adenosine monophosphate response element-binding protein, as downstream targets of mitogens, with a specific focus on hematopoietic cytokine signaling and the role these proteins play in gene regulation.
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Affiliation(s)
- Patricia Mora-Garcia
- Department of Pediatrics, Division of Hematology-Oncology, Mattel Children's Hospital, David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA
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21
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Marino VJ, Sterin-Prync AE, Roguin LP. Change in the accessibility of an epitope of the human granulocyte-colony stimulating factor after binding to receptors. Cytokine 2003; 22:5-11. [PMID: 12946100 DOI: 10.1016/s1043-4666(03)00099-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In a previous work we demonstrated that monoclonal antibody (mAb) 8C2 recognized a human granulocyte-colony stimulating factor (hG-CSF) region left unmasked after binding to placenta receptors, whereas mAb 6E3 defined a receptor-buried epitope. Herein we examined the role of these antigenic regions on the proliferative response induced by hG-CSF on a myeloid leukaemia cell line. Both mAbs significantly inhibited the hG-CSF-induced cell growing, although epitope 8C2 but not 6E3 remained exposed in hG-CSF:cell receptor complexes. When cytokine:receptor complexes already formed at 4 degrees C were incubated 1 h at 37 degrees C under conditions preventing the internalization, a significant reduction in the amount of accessible 8C2 epitopes was evident. However, this effect was not observed when mAb 8C2:hG-CSF complexes previously bound to cells were incubated at 37 degrees C. Thus, results suggest that a receptor oligomerization process could account for the temperature-induced epitope 8C2 masking. The identification of epitope 8C2 accomplished by synthesis of overlapping octapeptides, revealed that it is formed by sequences 39-52 and 155-164, both in close proximity in the three-dimensional structure of the hG-CSF molecule. Since part of this region has been proposed as a second binding site to receptors, we infer that the change of epitope 8C2 accessibility could be the result of either receptor aggregation or epitope binding to another receptor. In addition, our data support the hypothesis that a ligand-induced receptor oligomerization is required for transduction of cytokine signals.
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Affiliation(s)
- Verónica J Marino
- Facultad de Farmacia y Bioquímica, Instituto de Química y Fisicoquimica Biológicas (UBA-CONICET), Junin 956, 1113 Buenos Aires, Argentina
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22
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Doyle ML, Tian SS, Miller SG, Kessler L, Baker AE, Brigham-Burke MR, Dillon SB, Duffy KJ, Keenan RM, Lehr R, Rosen J, Schneeweis LA, Trill J, Young PR, Luengo JI, Lamb P. Selective binding and oligomerization of the murine granulocyte colony-stimulating factor receptor by a low molecular weight, nonpeptidyl ligand. J Biol Chem 2003; 278:9426-34. [PMID: 12524421 DOI: 10.1074/jbc.m209220200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Granulocyte colony-stimulating factor regulates neutrophil production by binding to a specific receptor, the granulocyte colony-stimulating factor receptor, expressed on cells of the granulocytic lineage. Recombinant forms of granulocyte colony-stimulating factor are used clinically to treat neutropenias. As part of an effort to develop granulocyte colony-stimulating factor mimics with the potential for oral bioavailability, we previously identified a nonpeptidyl small molecule (SB-247464) that selectively activates murine granulocyte colony-stimulating factor signal transduction pathways and promotes neutrophil formation in vivo. To elucidate the mechanism of action of SB-247464, a series of cell-based and biochemical assays were performed. The activity of SB-247464 is strictly dependent on the presence of zinc ions. Titration microcalorimetry experiments using a soluble murine granulocyte colony-stimulating factor receptor construct show that SB-247464 binds to the extracellular domain of the receptor in a zinc ion-dependent manner. Analytical ultracentrifugation studies demonstrate that SB-247464 induces self-association of the N-terminal three-domain fragment in a manner that is consistent with dimerization. SB-247464 induces internalization of granulocyte colony-stimulating factor receptor on intact cells, consistent with a mechanism involving receptor oligomerization. These data show that small nonpeptidyl compounds are capable of selectively binding and inducing productive oligomerization of cytokine receptors.
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Affiliation(s)
- Michael L Doyle
- Department of Medicinal Chemistry, GlaxoSmithKline, Collegeville, Pennsylvania 19426, USA
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23
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Sarkar CA, Lowenhaupt K, Horan T, Boone TC, Tidor B, Lauffenburger DA. Rational cytokine design for increased lifetime and enhanced potency using pH-activated "histidine switching". Nat Biotechnol 2002; 20:908-13. [PMID: 12161759 DOI: 10.1038/nbt725] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We describe a method for the rational design of more effective therapeutic proteins using amino acid substitutions that reduce receptor binding affinity in intracellular endosomal compartments, thereby leading to increased recycling in the ligand-sorting process and consequently resulting in longer half-life in extracellular medium. We demonstrate this approach for granulocyte colony-stimulating factor by using computationally predicted histidine substitutions that switch protonation states between cell-surface and endosomal pH. Molecular modeling of binding electrostatics indicates two different single-histidine mutants that fulfill our design requirements; experimental assays demonstrate that each mutant indeed exhibits an order-of-magnitude increase in medium half-life along with enhanced potency due to increased endocytic recycling.
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Affiliation(s)
- Casim A Sarkar
- Department of Chemical Engineering, Biotechnology Processing Center, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, USA
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24
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Luo P, Hayes RJ, Chan C, Stark DM, Hwang MY, Jacinto JM, Juvvadi P, Chung HS, Kundu A, Ary ML, Dahiyat BI. Development of a cytokine analog with enhanced stability using computational ultrahigh throughput screening. Protein Sci 2002; 11:1218-26. [PMID: 11967378 PMCID: PMC2373568 DOI: 10.1110/ps.4580102] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Granulocyte-colony stimulating factor (G-CSF) is used worldwide to prevent neutropenia caused by high-dose chemotherapy. It has limited stability, strict formulation and storage requirements, and because of poor oral absorption must be administered by injection (typically daily). Thus, there is significant interest in developing analogs with improved pharmacological properties. We used our ultrahigh throughput computational screening method to improve the physicochemical characteristics of G-CSF. Improving these properties can make a molecule more robust, enhance its shelf life, or make it more amenable to alternate delivery systems and formulations. It can also affect clinically important features such as pharmacokinetics. Residues in the buried core were selected for optimization to minimize changes to the surface, thereby maintaining the active site and limiting the designed protein's potential for antigenicity. Using a structure that was homology modeled from bovine G-CSF, core designs of 25-34 residues were completed, corresponding to 10(21)-10(28) sequences screened. The optimal sequence from each design was selected for biophysical characterization and experimental testing; each had 10-14 mutations. The designed proteins showed enhanced thermal stabilities of up to 13 degrees C, displayed five-to 10-fold improvements in shelf life, and were biologically active in cell proliferation assays and in a neutropenic mouse model. Pharmacokinetic studies in monkeys showed that subcutaneous injection of the designed analogs results in greater systemic exposure, probably attributable to improved absorption from the subcutaneous compartment. These results show that our computational method can be used to develop improved pharmaceuticals and illustrate its utility as a powerful protein design tool.
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Affiliation(s)
- Peizhi Luo
- Xencor, Inc., 111 W. Lemon Avenue, Monrovia, CA 91016, USA
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25
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Abstract
In the light scattering technique, glycosylation gives rise to excess light scattering for glycoproteins. Assuming additivity of refractive index and using an appropriate refractive index increment for carbohydrate, one can determine the degree of glycosylation from the excess light scattering. Here we have used size-exclusion chromatography in combination with online light scattering, UV absorbance, and refractive index. The results show that the technique accurately determines the carbohydrate content of recombinant stem cell factor.
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Affiliation(s)
- T Arakawa
- Alliance Protein Laboratories, 3957 Corte Cancion, Thousand Oaks, California 91360, USA.
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26
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Layton JE, Hall NE, Connell F, Venhorst J, Treutlein HR. Identification of ligand-binding site III on the immunoglobulin-like domain of the granulocyte colony-stimulating factor receptor. J Biol Chem 2001; 276:36779-87. [PMID: 11468284 DOI: 10.1074/jbc.m104787200] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The granulocyte colony-stimulating factor receptor (G-CSF-R) forms a tetrameric complex with G-CSF containing two ligand and two receptor molecules. The N-terminal Ig-like domain of the G-CSF-R is required for receptor dimerization, but it is not known whether it binds G-CSF or interacts elsewhere in the complex. Alanine scanning mutagenesis was used to show that residues in the Ig-like domain of the G-CSF-R (Phe(75), Gln(87), and Gln(91)) interact with G-CSF. This binding site for G-CSF overlapped with the binding site of a neutralizing anti-G-CSF-R antibody. A model of the Ig-like domain showed that the binding site is very similar to the viral interleukin-6 binding site (site III) on the Ig-like domain of gp130, a related receptor. To further characterize the G-CSF-R complex, exposed and inaccessible regions of monomeric and dimeric ligand-receptor complexes were mapped with monoclonal antibodies. The results showed that the E helix of G-CSF was inaccessible in the dimeric but exposed in the monomeric complex, suggesting that this region binds to the Ig-like domain of the G-CSF-R. In addition, the N terminus of G-CSF was exposed to antibody binding in both complexes. These data establish that the dimerization interface of the complete receptor complex is different from that in the x-ray structure of a partial complex. A model of the tetrameric G-CSF.G-CSF-R complex was prepared, based on the viral interleukin-6.gp130 complex, which explains these and previously published data.
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Affiliation(s)
- J E Layton
- Ludwig Institute for Cancer Research, Melbourne Tumour Biology Branch and the Cooperative Research Centre for Cellular Growth Factors, Parkville, Victoria 3050, Australia.
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27
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Wen J, Zhang M, Horan TP, Philo JS, Li T, Wypych J, Mendiaz EA, Langley KE, Aoki KH, Kuwamoto M, Kita Y, Arakawa T. Copper staining method for extracting biologically active proteins from native gels. Biosci Biotechnol Biochem 2001; 65:1315-20. [PMID: 11471730 DOI: 10.1271/bbb.65.1315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
An attempt was made to make protein bands visible on native gel using copper staining, since such a mild staining procedure would make the entire native gel electrophoresis process non-denaturing. Copper staining not only was able to detect various proteins on native gel with reasonable sensitivity, but also made extraction and recovery of active proteins possible from the gel using a gentle procedure.
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Affiliation(s)
- J Wen
- Amgen, Inc., Amgen Center, Thousand Oaks, CA 91320, USA
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28
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Monahan JB, Hood WF, Welply JK, Shieh JJ, Polazzi JO, Li X. Bivalent binding and signaling characteristics of Leridistim, a novel chimeric dual agonist of interleukin-3 and granulocyte colony-stimulating factor receptors. Exp Hematol 2001; 29:416-24. [PMID: 11301181 DOI: 10.1016/s0301-472x(01)00611-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Leridistim is a member of a novel family of engineered chimeric cytokines, myelopoietins, that contain agonists of both interleukin-3 (IL-3) receptors (IL-3R) and granulocyte colony-stimulating factor (G-CSF) receptors (G-CSFR). To more clearly understand Leridistim's function at the molecular level, binding to both IL-3R and G-CSFR and subsequent signaling characteristics have been delineated. The affinity of Leridistim for the human G-CSFR was found to be comparable to that of native G-CSF (IC(50) = 0.96 nM and 1.0 nM, respectively). Both Leridistim and G-CSF induced receptor tyrosine phosphorylation to a similar maximal level. Compared with native recombinant human IL-3 (rhIL-3), Leridistim was found to possess higher affinity for the IL-3R alpha chain (IL-3Ralpha) (IC(50) = 85 nM and 162 nM, respectively). However, the increase in Leridistim binding affinity to the functional, high-affinity heterodimeric IL-3Ralphabeta(c) receptor is lower than that observed with rhIL-3 (85 nM and 14 nM vs 162 nM and 3.5 nM, respectively). Leridistim induced tyrosine phosphorylation of beta(c) to a level comparable to native IL-3, and the level of JAK2 tyrosine phosphorylation in cells expressing both IL-3R and G-CSFR was comparable to that observed with IL-3 or G-CSF alone. The ability of Leridistim to interact with IL-3R and G-CSFR simultaneously was demonstrated using surface plasmon resonance analysis. These studies were extended to demonstrate that Leridistim exhibited a higher affinity for the IL-3R on cells that express both the IL-3Ralphabeta(c) and the G-CSFR (IC(50) = 2 nM) compared with cells that contain the IL-3Ralphabeta(c) alone (IC(50) = 14 nM). Leridistim binds to both IL-3R and G-CSFR simultaneously and has been shown to activate both receptors. The bivalent avidity may explain the unique biologic effects and unexpected potency of Leridistim in hematopoietic cells compared with rhIL-3 or G-CSF alone or in combination.
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MESH Headings
- Animals
- Antigens, CD34/analysis
- Bone Marrow Cells/immunology
- Bone Marrow Cells/metabolism
- Cell Line
- Cricetinae
- DNA/metabolism
- DNA-Binding Proteins/metabolism
- Dimerization
- Electrophoresis
- Granulocyte Colony-Stimulating Factor/metabolism
- Granulocyte Colony-Stimulating Factor/pharmacology
- Humans
- Interleukin-3/genetics
- Interleukin-3/metabolism
- Janus Kinase 2
- Leukemia, Myeloid, Acute
- Mice
- Milk Proteins
- Phosphorylation
- Phosphotyrosine/metabolism
- Protein-Tyrosine Kinases/metabolism
- Proto-Oncogene Proteins
- Receptors, Granulocyte Colony-Stimulating Factor/agonists
- Receptors, Granulocyte Colony-Stimulating Factor/genetics
- Receptors, Granulocyte Colony-Stimulating Factor/metabolism
- Receptors, Interleukin-3/agonists
- Receptors, Interleukin-3/genetics
- Receptors, Interleukin-3/metabolism
- Recombinant Fusion Proteins/metabolism
- Recombinant Proteins/metabolism
- STAT5 Transcription Factor
- Signal Transduction
- Surface Plasmon Resonance
- Trans-Activators/metabolism
- Transfection
- Tumor Cells, Cultured
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Affiliation(s)
- J B Monahan
- Discovery Research, Pharmacia Corporation, 700 Chesterfield Village Parkway, Chesterfield, MO 63017, USA.
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29
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Ishibashi M, Tokunaga H, Arakawa T, Tokunaga M. Expression, purification, and characterization of the active immunoglobulin-like domain of human granulocyte-colony-stimulating factor receptor in Escherichia coli. Protein Expr Purif 2001; 21:317-22. [PMID: 11237694 DOI: 10.1006/prep.2000.1381] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We succeeded in the expression, purification, and refolding of the immunoglobulin-like (Ig) domain of human granulocyte-colony-stimulating factor (G-CSF) receptor with amino-terminal His-tag in Escherichia coli. The refolded Ig domain bound to a G-CSF affinity column and could be eluted with free G-CSF as a receptor-ligand complex, demonstrating that the Ig domain has the information necessary for binding its ligand, G-CSF. The eluted His-Ig/G-CSF complex could be separated from excess G-CSF by Ni-NTA column chromatography. The yield of this active recombinant His-Ig protein is about 0.72 mg per liter of culture. Its small size and the ease of production make this receptor fragment a useful reagent for the structural analysis of its complex with G-CSF.
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Affiliation(s)
- M Ishibashi
- Laboratory of Applied and Molecular Microbiology, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan
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30
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Philo JS. Sedimentation equilibrium analysis of mixed associations using numerical constraints to impose mass or signal conservation. Methods Enzymol 2001; 321:100-20. [PMID: 10909053 DOI: 10.1016/s0076-6879(00)21189-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- J S Philo
- Alliance Protein Laboratories, Inc., Thousand Oaks, California 91360-2823, USA
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31
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Akbarzadeh S, Layton JE. Granulocyte colony-stimulating factor receptor: Structure and function. VITAMINS & HORMONES 2001; 63:159-94. [PMID: 11358114 DOI: 10.1016/s0083-6729(01)63006-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Affiliation(s)
- S Akbarzadeh
- Ludwig Institute for Cancer Research, Melbourne Tumour Biology Branch, Royal Melbourne Hospital, Parkville, Victoria, Australia
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32
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Gopalakrishnan SM, Warrior U, Burns D, Groebe DR. Evaluation of electrochemiluminescent technology for inhibitors of granulocyte colony-stimulating factor receptor binding. JOURNAL OF BIOMOLECULAR SCREENING 2000; 5:369-76. [PMID: 11080696 DOI: 10.1177/108705710000500509] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
An electrochemiluminescent (ECL) assay was developed to identify compounds that inhibit the interaction of granulocyte colony-stimulating factor (GCSF) with its recombinant human receptor. The ECL technology uses a tris-(bipyridine) chelate of ruthenium, which, in the presence of excess tripropylamine, undergoes a redox reaction cycle to produce light. Paramagnetic beads with primary antibody were coated with secondary anti-GCSF receptor antibody, which were then bound with GCSF receptor. These samples were incubated with ruthenylated GCSF in the presence and absence of test compounds. The bead density, receptor and ligand concentrations, and incubation time were optimized in the assay. A set of mixed compound plates was screened to examine the feasibility of using this technology in high throughput screening. The results from this format were found to be comparable to the assay performed using a time-resolved fluorescence format.
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33
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Aritomi M, Kunishima N, Okamoto T, Kuroki R, Ota Y, Morikawa K. Atomic structure of the GCSF-receptor complex showing a new cytokine-receptor recognition scheme. Nature 1999; 401:713-7. [PMID: 10537111 DOI: 10.1038/44394] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Granulocyte colony-stimulating factor (GCSF) is the principal growth factor regulating the maturation, proliferation and differentiation of the precursor cells of neutrophilic granulocytes and is used to treat neutropenia. GCSF is a member of the long-chain subtype of the class 1 cytokine superfamily, which includes growth hormone, erythropoietin, interleukin 6 and oncostatin M. Here we have determined the crystal structure of GCSF complexed to the BN-BC domains, the principal ligand-binding region of the GCSF receptor (GCSFR). The two receptor domains form a complex in a 2:2 ratio with the ligand, with a non-crystallographic pseudo-twofold axis through primarily the interdomain region and secondarily the BC domain. This structural view of a gp130-type receptor-ligand complex presents a new molecular basis for cytokine-receptor recognition.
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Affiliation(s)
- M Aritomi
- Biomolecular Engineering Research Institute, Suita-city, Osaka, Japan
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34
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Ward AC, van Aesch YM, Gits J, Schelen AM, de Koning JP, van Leeuwen D, Freedman MH, Touw IP. Novel point mutation in the extracellular domain of the granulocyte colony-stimulating factor (G-CSF) receptor in a case of severe congenital neutropenia hyporesponsive to G-CSF treatment. J Exp Med 1999; 190:497-507. [PMID: 10449521 PMCID: PMC2195597 DOI: 10.1084/jem.190.4.497] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Severe congenital neutropenia (SCN) is a heterogeneous condition characterized by a drastic reduction in circulating neutrophils and a maturation arrest of myeloid progenitor cells in the bone marrow. Usually this condition can be successfully treated with granulocyte colony-stimulating factor (G-CSF). Here we describe the identification of a novel point mutation in the extracellular domain of the G-CSF receptor (G-CSF-R) in an SCN patient who failed to respond to G-CSF treatment. When this mutant G-CSF-R was expressed in myeloid cells, it was defective in both proliferation and survival signaling. This correlated with diminished activation of the receptor complex as determined by signal transducer and activator of transcription (STAT) activation, although activation of STAT5 was more affected than STAT3. Interestingly, the mutant receptor showed normal affinity for ligand, but a reduced number of ligand binding sites compared with the wild-type receptor. This suggests that the mutation in the extracellular domain affects ligand-receptor complex formation with severe consequences for intracellular signal transduction. Together these data add to our understanding of the mechanisms of cytokine receptor signaling, emphasize the role of GCSFR mutations in the etiology of SCN, and implicate such mutations in G-CSF hyporesponsiveness.
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Affiliation(s)
- A C Ward
- Institute of Hematology, Erasmus University Rotterdam, 3000 DR Rotterdam, The Netherlands.
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35
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Kim H, Baumann H. Dual signaling role of the protein tyrosine phosphatase SHP-2 in regulating expression of acute-phase plasma proteins by interleukin-6 cytokine receptors in hepatic cells. Mol Cell Biol 1999; 19:5326-38. [PMID: 10409724 PMCID: PMC84376 DOI: 10.1128/mcb.19.8.5326] [Citation(s) in RCA: 139] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
One of the major actions of interleukin-6 (IL-6) is the transcriptional activation of acute-phase plasma proteins (APP) genes in liver cells. Signaling by the IL-6 receptor is mediated through the signal transducing subunit gp130 and involves the activation of Janus-associated kinases (JAKs), signal transducer and activator of transcription 3 (STAT3), and mitogen-activated protein (MAP) kinase. Functional analysis of gp130 in rat hepatoma cells by using transduced chimeric G-CSFR-gp130 receptor constructs demonstrates that SHP-2, the Src homology 2 (SH2) domain-containing protein tyrosine phosphatase, acts as a negative regulator of the JAK/STAT signaling in part by downregulating JAK activity, thereby indirectly moderating the induction of STAT3-dependent APP genes. This study shows that in hepatoma cells, the recruitment and tyrosine phosphorylation of SHP-2, but not SHC, is the primary signaling event associated with the activation of MAP kinases (ERK1/2) by gp130. Overexpression of truncated SHP-2 that lacks Grb2-interacting sites, but not the full-length catalytically inactive SHP-2, reduces ERK activation by IL-6, confirming the signal-mediating role of SHP-2. Activation of ERK1/2 is correlated with induction of the immediate-early response genes. Stimulation of the c-fos, c-jun, and egr-1 genes is essentially absent in cells expressing gp130 with a Y759F mutation, which is unable to recruit SHP-2. Interestingly, both JAK/STAT and SHP-2 pathways regulate the induction of the junB gene. Moreover, disengagement of SHP-2 from gp130 signaling not only enhances APP gene induction but also further reduces cell proliferation, in part correlated with the attenuated expression of immediate-early response genes. These results suggest that IL-6 regulation of APP genes is affected by SHP-2 in two ways: SHP-2 acts as a phosphatase on the JAK/STAT pathway and serves as linker to the MAP kinase pathway, which in turn moderates APP production.
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MESH Headings
- Acute-Phase Proteins/biosynthesis
- Acute-Phase Proteins/genetics
- Acute-Phase Reaction/genetics
- Adaptor Proteins, Signal Transducing
- Animals
- Antigens, CD/physiology
- Calcium-Calmodulin-Dependent Protein Kinases/physiology
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/pathology
- Cytokine Receptor gp130
- DNA-Binding Proteins/physiology
- Enzyme Activation
- GRB2 Adaptor Protein
- Gene Expression Regulation
- Gene Expression Regulation, Neoplastic
- Humans
- Interleukin-6/physiology
- Intracellular Signaling Peptides and Proteins
- Janus Kinase 1
- Liver/drug effects
- Liver/metabolism
- Liver Neoplasms/genetics
- Liver Neoplasms/metabolism
- Liver Neoplasms/pathology
- Liver Neoplasms, Experimental/genetics
- Liver Neoplasms, Experimental/metabolism
- Liver Neoplasms, Experimental/pathology
- Membrane Glycoproteins/physiology
- Mitogen-Activated Protein Kinase 1
- Mitogen-Activated Protein Kinase 3
- Mitogen-Activated Protein Kinases
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/genetics
- Phosphorylation
- Protein Processing, Post-Translational
- Protein Tyrosine Phosphatase, Non-Receptor Type 11
- Protein Tyrosine Phosphatase, Non-Receptor Type 6
- Protein Tyrosine Phosphatases/physiology
- Protein-Tyrosine Kinases/physiology
- Proteins/metabolism
- Rats
- Receptors, Interleukin-6/drug effects
- Receptors, Interleukin-6/physiology
- Recombinant Fusion Proteins/physiology
- SH2 Domain-Containing Protein Tyrosine Phosphatases
- STAT3 Transcription Factor
- Signal Transduction/physiology
- Trans-Activators/physiology
- Transcription, Genetic
- Transcriptional Activation
- Transfection
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Affiliation(s)
- H Kim
- Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, Buffalo, New York 14263, USA
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36
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Layton JE, Shimamoto G, Osslund T, Hammacher A, Smith DK, Treutlein HR, Boone T. Interaction of granulocyte colony-stimulating factor (G-CSF) with its receptor. Evidence that Glu19 of G-CSF interacts with Arg288 of the receptor. J Biol Chem 1999; 274:17445-51. [PMID: 10364174 DOI: 10.1074/jbc.274.25.17445] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Granulocyte colony-stimulating factor (G-CSF) forms a tetrameric complex with its receptor, comprising two G-CSF and two receptor molecules. The structure of the complex is unknown, and it is unclear whether there are one or two binding sites on G-CSF and the receptor. The immunoglobulin-like domain and the cytokine receptor homologous module of the receptor are involved in G-CSF binding, and Arg288 in the cytokine receptor homologous module is particularly important. To identify residues in G-CSF that interact with Arg288, selected charged residues in G-CSF were mutated to Ala. To clarify whether there are two binding sites, a chimeric receptor was created in which the Ig domain was replaced with that of the related receptor gp130. This chimera bound G-CSF but could not transduce a signal, consistent with failure of dimerization and loss of one binding site. The G-CSF mutants had reduced mitogenic activity on cells expressing wild-type receptor. When tested with the chimeric receptor, all G-CSF mutants except one (E46A) showed reduced binding, suggesting that Glu46 is important for interaction with the Ig domain. On cells expressing R288A receptor, all the G-CSF mutants except E19A showed reduced mitogenic activity, indicating that Glu19 of G-CSF interacts with Arg288 of the receptor.
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Affiliation(s)
- J E Layton
- Ludwig Institute for Cancer Research, Melbourne Tumour Biology Branch, Parkville 3050, Australia.
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37
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Lu HS, Fausset PR, Narhi LO, Horan T, Shinagawa K, Shimamoto G, Boone TC. Chemical modification and site-directed mutagenesis of methionine residues in recombinant human granulocyte colony-stimulating factor: effect on stability and biological activity. Arch Biochem Biophys 1999; 362:1-11. [PMID: 9917323 DOI: 10.1006/abbi.1998.1022] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Chemical modification and mutagenesis of methionines in recombinant human granulocyte colony-stimulating factor (G-CSF) were investigated. Selective oxidation of G-CSF by H2O2 and t-butyl hydroperoxide leads to generation of different oxidized forms. Four modified forms were isolated and shown to contain 1 to 4 oxidized methionyl residues. All methionines in G-CSF are reactive, with reaction kinetics following the order of Met1>Met138>Met127>>>Met122. H2O2 oxidation of Met122 is relatively slow and is biphasic with a faster second reaction phase being affected by the oxidation of Met127. All oxidized forms retain gross G-CSF conformation similar to that of the native molecule and are able to bind the soluble G-CSF receptor. However, G-CSF form oxidized at both Met127 and Met122 is unstable and exhibits decreased ability to dimerize the receptor after exposure to acid or elevated temperature. All modified forms, except Met1-oxidized G-CSF, also show significantly lower biological activity. Our data suggest that Met138 is solvent accessible and its surrounding microenvironment may be critical for G-CSF function, whereas Met127 is less accessible to solvent and Met122 is near the hydrophobic core. Oxidation at both Met127 and Met122 results in alterations of G-CSF structure that affect the apparent molecular size, polarity, and stability and lead to the loss of G-CSF biological function. G-CSF variants with Leu replacement at Met127 or at Met138 are not completely resistant to oxidation-induced inactivation, while the variant with Leu replacement at both sites is more stable and can retain in vitro biological activity following oxidation.
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Affiliation(s)
- H S Lu
- Department of Protein Structure, Department of Protein Chemistry, Department of Process Science, Amgen Inc., 1 Amgen Center Drive, Thousand Oaks, California, 91320, USA.
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38
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Mammen M, Choi SK, Whitesides GM. Polyvalente Wechselwirkungen in biologischen Systemen: Auswirkungen auf das Design und die Verwendung multivalenter Liganden und Inhibitoren. Angew Chem Int Ed Engl 1998. [DOI: 10.1002/(sici)1521-3757(19981016)110:20<2908::aid-ange2908>3.0.co;2-2] [Citation(s) in RCA: 522] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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39
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Horan TP, Simonet L, Jacobsen R, Mann M, Haniu M, Wen J, Arakawa T, Kuwamoto M, Martin F. Coexpression of G-CSF with an unglycosylated G-CSF receptor mutant results in secretion of a stable complex. Protein Expr Purif 1998; 14:45-53. [PMID: 9758750 DOI: 10.1006/prep.1998.0942] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previously, we have shown that the entire extracellular domain of the granulocyte-colony stimulating factor receptor (sG-CSFr) produced in Chinese hamster ovary (CHO) cells forms a stable complex with its ligand G-CSF, at a stoichiometry of 2:2. A truncated receptor molecule consisting of the cytokine receptor homology domain and N-terminus Ig-like domain (Ig CRH) behaves quite similarly. Both of these forms of the receptor are highly glycosylated. To address the importance of glycosylation toward receptor activity and stability, and possibly obtain nonglycosylated receptor for crystallization, mutations were made to replace four Asn residues which are N-glycosylated in the truncated receptor. Virtually no receptor was recovered from conditioned media of CHO cells transfected with this mutant construct, although a high-level of mRNA coding for receptor was detected; this mRNA was translated as determined by Western blots of cell lysates. These results indicate that the translated product is apparently not secreted from these cells. Cells transfected with mutant receptor cDNA were cotransfected with a cDNA construct expressing G-CSF in which the single O-glycosylation site was eliminated by mutation. Upon fermentation of the cotransfectants, we observed a large amount of receptor-ligand complex in the conditioned media. The purified unglycosylated complex appeared to be of the same binding stoichiometry and approximate binding affinity as that of complex formed by addition of purified ligand and unmutated receptor. These results show that while glycosylation of sG-CSFr is not necessary for ligand binding, it appears to be crucial in folding and export from the cell.
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Affiliation(s)
- T P Horan
- Amgen Inc., One Amgen Center Drive, Thousand Oaks, California, 91320-1789, USA
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40
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Tian SS, Lamb P, King AG, Miller SG, Kessler L, Luengo JI, Averill L, Johnson RK, Gleason JG, Pelus LM, Dillon SB, Rosen J. A small, nonpeptidyl mimic of granulocyte-colony-stimulating factor [see commetns]. Science 1998; 281:257-9. [PMID: 9657720 DOI: 10.1126/science.281.5374.257] [Citation(s) in RCA: 131] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A nonpeptidyl small molecule SB 247464, capable of activating granulocyte-colony-stimulating factor (G-CSF) signal transduction pathways, was identified in a high-throughput assay in cultured cells. Like G-CSF, SB 247464 induced tyrosine phosphorylation of multiple signaling proteins and stimulated primary murine bone marrow cells to form granulocytic colonies in vitro. It also elevated peripheral blood neutrophil counts in mice. The extracellular domain of the murine G-CSF receptor was required for the activity of SB 247464, suggesting that the compound acts by oligomerizing receptor chains. The results indicate that a small molecule can activate a receptor that normally binds a relatively large protein ligand.
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Affiliation(s)
- S S Tian
- Department of Transcription Research, Ligand Pharmaceuticals, San Diego, CA 92121, USA
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41
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Abstract
Cell surface receptors play a central role in the regulation of both cellular and systemic physiology by mediating intercellular communication, facilitating protein trafficking, and regulating virtually all intracellular processes. Receptor expression is often cell specific and is determined by cellular lineage, genetics, and a variety of factors in the extracellular milieu. As receptors are generally localized on the plasma membrane and differentially expressed in certain cell types and tissues, they provide a potential target for drug delivery. However, since most receptors are integrally connected with intracellular signal transduction networks, targeting via these receptors may elicit a biological response. This review describes some established and emerging concepts regarding the structure and functions of receptors. In addition, some aspects related to the regulation and crosstalk between receptors are discussed.
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42
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Abstract
The assimilation, storage, and disposition of nutrient energy constitute a complex homeostatic system central to the survival of both prokaryotic and eukaryotic organisms. In vertebrates, and especially among land dwelling mammalian species, the ability to store large quantities of energy-dense fuel in the form of adipose tissue triglyceride permits survival during prolonged periods of food deprivation. In order to maintain such fuel stores during times of dietary scarcity or surfeit, some balance between energy intake and expenditure must be achieved. Lesions of the hypothalamus alter body weight suggesting that this brain region regulates nutritional state. These and other studies led to the hypothesis that body weight was regulated by a feedback loop in which peripheral signals reported nutritional information to an integratory center in the brain. However, the identity of these nutrition signals proved elusive.
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Affiliation(s)
- J M Friedman
- Howard Hughes Medical Institute, New York, New York, USA
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43
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Layton JE, Iaria J, Smith DK, Treutlein HR. Identification of a ligand-binding site on the granulocyte colony-stimulating factor receptor by molecular modeling and mutagenesis. J Biol Chem 1997; 272:29735-41. [PMID: 9368043 DOI: 10.1074/jbc.272.47.29735] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Granulocyte colony-stimulating factor (G-CSF) initiates its effects on cells of the neutrophil lineage by inducing formation of a homodimeric receptor complex. The structure of the G-CSF receptor has not yet been determined, therefore we used molecular modeling to identify regions of the receptor that were likely to be involved in ligand binding. The G-CSF receptor sequence was aligned with all the available sequences of the gp130 and growth hormone receptor families and a model of the cytokine receptor homologous domain was constructed, based on the growth hormone receptor structure. Alanine substitution mutagenesis was performed on loops and individual residues that were predicted to bind ligand. Mutant receptors were expressed in factor-dependent Ba/F3 cells and assessed for proliferation response and ligand binding. Six residues were identified that significantly reduced receptor function, with Arg288 in the F'-G' loop having the greatest effect. These residues formed a binding face on the receptor model resembling the growth hormone receptor site, which suggests that the model is reasonable. However, electrostatic analysis of the model provided further evidence that the mechanism of receptor dimerization is different from that of the growth hormone receptor.
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Affiliation(s)
- J E Layton
- Ludwig Institute for Cancer Research, Melbourne Tumour Biology Branch, P. O. Box 2008, Royal Melbourne Hospital, Parkville, Australia 3050.
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44
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Devos R, Guisez Y, Van der Heyden J, White DW, Kalai M, Fountoulakis M, Plaetinck G. Ligand-independent dimerization of the extracellular domain of the leptin receptor and determination of the stoichiometry of leptin binding. J Biol Chem 1997; 272:18304-10. [PMID: 9218470 DOI: 10.1074/jbc.272.29.18304] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The leptin receptor is a class I transmembrane protein with either a short or a long cytoplasmic domain. Using chemical cross-linking we have analyzed the binding of leptin to its receptor. Cross-linking of radiolabeled leptin to different isoforms of the leptin receptor expressed on COS-1 cells reveals leptin receptor monomer, homodimer, and oligomer complexes. Cotransfection of the long and short form of the leptin receptor did not provide any evidence for the formation of heterodimer complexes. Soluble forms consisting of either the entire extracellular domain or the two cytokine receptor homologous domains of the leptin receptor were purified to homogeneity from recombinant baculovirus-infected insect cells by leptin affinity chromatography. Gel filtration chromatography showed that these proteins exist in a dimeric form. Analysis of the complex formed between soluble leptin receptor and leptin by native polyacrylamide gel electrophoresis, and data obtained from the amino acid composition of the complex provide direct evidence that the extracellular domain of the leptin receptor binds leptin in a 1:1 ratio.
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Affiliation(s)
- R Devos
- Roche Research Gent, F. Hoffmann-La Roche & Co., B-9000 Gent, Belgium
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45
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Gervais V, Zerial A, Oschkinat H. NMR investigations of the role of the sugar moiety in glycosylated recombinant human granulocyte-colony-stimulating factor. EUROPEAN JOURNAL OF BIOCHEMISTRY 1997; 247:386-95. [PMID: 9249051 DOI: 10.1111/j.1432-1033.1997.00386.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Human granulocyte-colony-stimulating factor (G-CSF) is a hematopoietic growth factor that plays a major role in the stimulation of the proliferation and maturation of granulocyte neutrophil cells. With the recent increased understanding of its biological properties in vivo together with available preparations of recombinant human G-CSF, this growth factor has become an essential agent for clinical applications. The presence of an O-linked carbohydrate chain at position 133 greatly improves the physical stability of the protein. To clarify the molecular basis for the stabilisation effect of saccharide moieties on human G-CSF the whole glycoprotein expressed in CHO cells has been investigated by means of two 1H-NMR-spectroscopy and two 1H-detected-heteronuclear 1H-13C experiments at natural abundance, and compared with the non-glycosylated form. The present NMR study reports assignments of 1H and 13C resonances of the bound saccharidic chain NeuNAc(alpha2-3)Gal(beta1-3)[NeuNAc(alpha2-6)]GalNAc, where NeuNAc represents N-acetylneuraminic acid, and demonstrates the alpha-anomeric configuration of the N-acetylgalactosamine-threonine linkage. It also provides results suggesting that the carbohydrate moiety reduces the local mobility around the glycosylation site, which could be responsible for the stabilising effect observed on the glycoprotein.
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Affiliation(s)
- V Gervais
- European Molecular Biology Laboratory, Heidelberg, Germany
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46
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Herr AB, Ornitz DM, Sasisekharan R, Venkataraman G, Waksman G. Heparin-induced self-association of fibroblast growth factor-2. Evidence for two oligomerization processes. J Biol Chem 1997; 272:16382-9. [PMID: 9195945 DOI: 10.1074/jbc.272.26.16382] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Fibroblast growth factor-2 (FGF-2), a potent angiogenic factor, requires heparin for dimerization and activation of the FGF receptor tyrosine kinase. The binding of multiple fibroblast growth factors by heparin may be necessary for dimerization of the FGF receptor. Analytical ultracentrifugation of FGF-2 in the presence of heparin-derived saccharides shows that both an active heparin octasaccharide and an inactive heparin-like disaccharide induce fibroblast growth factor-2 self-association. Analysis of the data indicates that the heparin octasaccharide induces a monomer-dimer-tetramer assembly of FGF-2 while the disaccharide induces a monomer-dimer equilibrium. Evidence is presented indicating that the dimer conformation induced by the heparin octasaccharide is a side by side dimer with the FGF-2 molecules cis to the heparin, while the disaccharide-induced dimer is a head to head dimer in which FGF-2 molecules are trans to the ligand. These results, combined with previous studies, support the model that formation of a specific side by side heparin-induced FGF-2 dimer is required for activation of the FGF receptor.
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Affiliation(s)
- A B Herr
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Young DC, Zhan H, Cheng QL, Hou J, Matthews DJ. Characterization of the receptor binding determinants of granulocyte colony stimulating factor. Protein Sci 1997; 6:1228-36. [PMID: 9194183 PMCID: PMC2143731 DOI: 10.1002/pro.5560060611] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We performed a series of experiments using alanine-scanning mutagenesis to locate side chains within human granulocyte colony-stimulating factor (G-CSF) that are involved in human G-CSF receptor binding. We constructed a panel of 28 alanine mutants that examined all surface exposed residues on helices A and D, as well as all charged residues on the surface of G-CSF. The G-CSF mutants were expressed in a transiently transfected mammalian cell line and quantitated by a sensitive biosensor method. We measured the activity of mutant proteins using an in vitro proliferation assay and an ELISA binding competition assay. These studies show that there is a region of five charged residues on helices A and C employed by G-CSF in binding its receptor, with the most important residue in this binding patch being Glu 19. Both wild-type G-CSF and the E19A mutant were expressed in E. coli. The re-folded proteins were found to have proliferative activities similar to the analogous proteins from mammalian cells: furthermore, biophysical analysis indicated that the E19A mutation does not cause gross structural perturbations in G-CSF. Although G-CSF is likely to signal through receptor homo-dimerization, we found no compelling evidence for a second receptor binding region. We also found no evidence of self-antagonism at high G-CSF concentrations, suggesting that, in contrast to human growth hormone (hGH) and erythropoietin (EPO), G-CSF probably does not signal via a pure 2:1 receptor ligand complex. Thus, G-CSF, while having a similar tertiary structure to hGH and EPO, uses different areas of the four helix bundle for high-affinity interaction with its receptor.
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Affiliation(s)
- D C Young
- Department of Molecular Biology, Arris Pharmaceutical Corporation, South San Francisco, California 94080, USA
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Lemmon MA, Bu Z, Ladbury JE, Zhou M, Pinchasi D, Lax I, Engelman DM, Schlessinger J. Two EGF molecules contribute additively to stabilization of the EGFR dimer. EMBO J 1997; 16:281-94. [PMID: 9029149 PMCID: PMC1169635 DOI: 10.1093/emboj/16.2.281] [Citation(s) in RCA: 265] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Receptor dimerization is generally considered to be the primary signaling event upon binding of a growth factor to its receptor at the cell surface. Little, however, is known about the precise molecular details of ligand-induced receptor dimerization, except for studies of the human growth hormone (hGH) receptor. We have analyzed the binding of epidermal growth factor (EGF) to the extracellular domain of its receptor (sEGFR) using titration calorimetry, and the resulting dimerization of sEGFR using small-angle X-ray scattering. EGF induces the quantitative formation of sEGFR dimers that contain two EGF molecules. The data obtained from the two approaches suggest a model in which one EGF monomer binds to one sEGFR monomer, and that receptor dimerization involves subsequent association of two monomeric (1:1) EGF-sEGFR complexes. Dimerization may result from bivalent binding of both EGF molecules in the dimer and/or receptor-receptor interactions. The requirement for two (possibly bivalent) EGF monomers distinguishes EGF-induced sEGFR dimerization from the hGH and interferon-gamma receptors, where multivalent binding of a single ligand species (either monomeric or dimeric) drives receptor oligomerization. The proposed model of EGF-induced sEGFR dimerization suggests possible mechanisms for both ligand-induced homo- and heterodimerization of the EGFR (or erbB) family of receptors.
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Affiliation(s)
- M A Lemmon
- Department of Pharmacology, New York University Medical Center, New York, NY 10016, USA
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Layton JE, Iaria J, Nicholson SE. Neutralising antibodies to the granulocyte colony-stimulating factor receptor recognise both the immunoglobulin-like domain and the cytokine receptor homologous domain. Growth Factors 1997; 14:117-30. [PMID: 9255604 DOI: 10.3109/08977199709021515] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To define regions of the granulocyte colony-stimulating factor (G-CSF) receptor that are important for ligand binding, neutralising monoclonal antibodies to the human receptor have been produced. Eleven antibodies recognised six different receptor epitopes. Antibodies from three of the epitope groups were able to detect the receptor by western blotting but did not inhibit G-CSF binding. The other three antibody groups inhibited G-CSF binding either completely (groups 1 and 2) or partially (group 3). All the antibodies inhibited proliferation of BA/F3 cells expressing the G-CSF receptor to varying extents. By using human-marine chimeric receptors, the binding sites of the antibodies were mapped to the immunoglobulin-like domain (groups 1 and 3), the cytokine receptor homologous domain (group 2) or the fibronectin type III domains (groups 4 to 6). These results show that the immunoglobulin-like and cytokine receptor homologous domains of the receptor are important for ligand binding and subsequent signalling.
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Affiliation(s)
- J E Layton
- Ludwig Institute for Cancer Research, Melbourne Tumour Biology Branch, Parkville, Australia
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