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Skokowa J, Hernandez Alvarez B, Coles M, Ritter M, Nasri M, Haaf J, Aghaallaei N, Xu Y, Mir P, Krahl AC, Rogers KW, Maksymenko K, Bajoghli B, Welte K, Lupas AN, Müller P, ElGamacy M. A topological refactoring design strategy yields highly stable granulopoietic proteins. Nat Commun 2022; 13:2948. [PMID: 35618709 PMCID: PMC9135769 DOI: 10.1038/s41467-022-30157-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 04/19/2022] [Indexed: 11/09/2022] Open
Abstract
Protein therapeutics frequently face major challenges, including complicated production, instability, poor solubility, and aggregation. De novo protein design can readily address these challenges. Here, we demonstrate the utility of a topological refactoring strategy to design novel granulopoietic proteins starting from the granulocyte-colony stimulating factor (G-CSF) structure. We change a protein fold by rearranging the sequence and optimising it towards the new fold. Testing four designs, we obtain two that possess nanomolar activity, the most active of which is highly thermostable and protease-resistant, and matches its designed structure to atomic accuracy. While the designs possess starkly different sequence and structure from the native G-CSF, they show specific activity in differentiating primary human haematopoietic stem cells into mature neutrophils. The designs also show significant and specific activity in vivo. Our topological refactoring approach is largely independent of sequence or structural context, and is therefore applicable to a wide range of protein targets. Skokowa et al. reconstruct the fold of a granulopoietic cytokine, resulting in de novo, hyperstable, highly active proteins with therapeutic potential for treating several neutropenia disorders.
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Affiliation(s)
- Julia Skokowa
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany.
| | | | - Murray Coles
- Max Planck Institute for Biology, 72076, Tübingen, Germany
| | - Malte Ritter
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Masoud Nasri
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Jérémy Haaf
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Narges Aghaallaei
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Yun Xu
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Perihan Mir
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Ann-Christin Krahl
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Katherine W Rogers
- Friedrich Miescher Laboratory of the Max Planck Society, 72076, Tübingen, Germany.,Division of Developmental Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Kateryna Maksymenko
- Max Planck Institute for Biology, 72076, Tübingen, Germany.,Friedrich Miescher Laboratory of the Max Planck Society, 72076, Tübingen, Germany
| | - Baubak Bajoghli
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Karl Welte
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Andrei N Lupas
- Max Planck Institute for Biology, 72076, Tübingen, Germany
| | - Patrick Müller
- Friedrich Miescher Laboratory of the Max Planck Society, 72076, Tübingen, Germany.,Department of Biology, University of Konstanz, 78464, Konstanz, Germany
| | - Mohammad ElGamacy
- Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, 72076, Tübingen, Germany. .,Friedrich Miescher Laboratory of the Max Planck Society, 72076, Tübingen, Germany. .,Heliopolis Biotechnology Ltd, Cambridge, CB24 9RX, UK. .,Max Planck Institute for Biology, 72076, Tübingen, Germany.
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Hernandez Alvarez B, Skokowa J, Coles M, Mir P, Nasri M, Maksymenko K, Weidmann L, Rogers KW, Welte K, Lupas AN, Müller P, ElGamacy M. Design of novel granulopoietic proteins by topological rescaffolding. PLoS Biol 2020; 18:e3000919. [PMID: 33351791 PMCID: PMC7755208 DOI: 10.1371/journal.pbio.3000919] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 11/24/2020] [Indexed: 11/18/2022] Open
Abstract
Computational protein design is rapidly becoming more powerful, and improving the accuracy of computational methods would greatly streamline protein engineering by eliminating the need for empirical optimization in the laboratory. In this work, we set out to design novel granulopoietic agents using a rescaffolding strategy with the goal of achieving simpler and more stable proteins. All of the 4 experimentally tested designs were folded, monomeric, and stable, while the 2 determined structures agreed with the design models within less than 2.5 Å. Despite the lack of significant topological or sequence similarity to their natural granulopoietic counterpart, 2 designs bound to the granulocyte colony-stimulating factor (G-CSF) receptor and exhibited potent, but delayed, in vitro proliferative activity in a G-CSF-dependent cell line. Interestingly, the designs also induced proliferation and differentiation of primary human hematopoietic stem cells into mature granulocytes, highlighting the utility of our approach to develop highly active therapeutic leads purely based on computational design. De novo designed cytokines that activate the G-CSF receptor show that the receptor-binding information can be encoded onto stable, miniaturised protein scaffolds that possess potent granulopoietic activity; such novel proteins provide for ideal candidates for protein-based therapeutics.
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Affiliation(s)
| | - Julia Skokowa
- University Hospital Tübingen, Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, Germany
- * E-mail: (JS); (ME)
| | - Murray Coles
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Perihan Mir
- University Hospital Tübingen, Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, Germany
| | - Masoud Nasri
- University Hospital Tübingen, Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, Germany
| | | | - Laura Weidmann
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | | | - Karl Welte
- University Hospital Tübingen, Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, Germany
| | - Andrei N. Lupas
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Patrick Müller
- University Hospital Tübingen, Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, Germany
- Friedrich Miescher Laboratory of the Max Planck Society Tübingen, Germany
| | - Mohammad ElGamacy
- Max Planck Institute for Developmental Biology, Tübingen, Germany
- University Hospital Tübingen, Division of Translational Oncology, Department of Hematology, Oncology, Clinical Immunology and Rheumatology, University Hospital Tübingen, Germany
- Friedrich Miescher Laboratory of the Max Planck Society Tübingen, Germany
- Heliopolis Biotechnology Ltd., London, United Kingdom
- * E-mail: (JS); (ME)
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Trottier AM, Druhan LJ, Kraft IL, Lance A, Feurstein S, Helgeson M, Segal JP, Das S, Avalos BR, Godley LA. Heterozygous germ line CSF3R variants as risk alleles for development of hematologic malignancies. Blood Adv 2020; 4:5269-5284. [PMID: 33108454 PMCID: PMC7594406 DOI: 10.1182/bloodadvances.2020002013] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 09/11/2020] [Indexed: 12/16/2022] Open
Abstract
Colony-stimulating factor 3 receptor (CSF3R) encodes the receptor for granulocyte colony-stimulating factor (G-CSF), a cytokine vital for granulocyte proliferation and differentiation. Acquired activating heterozygous variants in CSF3R are the main cause of chronic neutrophilic leukemia, a hyperproliferative disorder. In contrast, biallelic germ line hypomorphic variants in CSF3R are a rare cause of severe congenital neutropenia, a hypoproliferative condition. The impact of heterozygous germ line CSF3R variants, however, is unknown. We identified CSF3R as a new germ line hematologic malignancy predisposition gene through analysis of 832 next-generation sequencing tests conducted in 632 patients with hematologic malignancies. Among germ line CSF3R variants, 3 were abnormal in functional testing, indicating their deleterious nature. p.Trp547* was identified in 2 unrelated men with myelodysplastic syndromes diagnosed at 76 and 33 years of age, respectively. p.Trp547* is a loss-of-function nonsense variant in the extracellular domain that results in decreased CSF3R messenger RNA expression and abrogation of CSF3R surface expression and proliferative responses to G-CSF. p.Ala119Thr is a missense variant found in 2 patients with multiple myeloma and acute lymphoblastic leukemia, respectively. This variant is located between the extracellular immunoglobulin-like and cytokine receptor homology domains and results in decreased G-CSF sensitivity. p.Pro784Thr was identified in a 67-year-old man with multiple myeloma. p.Pro784Thr is a missense variant in the cytoplasmic domain that inhibits CSF3R internalization, producing a gain-of-function phenotype and G-CSF hypersensitivity. Our findings identify germ line heterozygous CSF3R variants as risk factors for development of myeloid and lymphoid malignancies.
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Affiliation(s)
- Amy M Trottier
- Section of Hematology/Oncology, Department of Medicine, and
- University of Chicago Comprehensive Cancer Center, University of Chicago, Chicago, IL
| | - Lawrence J Druhan
- Department of Hematologic Oncology and Blood Disorders, Levine Cancer Institute, Atrium Health, Charlotte, NC; and
| | - Ira L Kraft
- Section of Hematology/Oncology, Department of Medicine, and
- University of Chicago Comprehensive Cancer Center, University of Chicago, Chicago, IL
- Internal Medicine-Pediatrics Residency Program, Department of Medicine
| | - Amanda Lance
- Department of Hematologic Oncology and Blood Disorders, Levine Cancer Institute, Atrium Health, Charlotte, NC; and
| | - Simone Feurstein
- Section of Hematology/Oncology, Department of Medicine, and
- University of Chicago Comprehensive Cancer Center, University of Chicago, Chicago, IL
| | | | - Jeremy P Segal
- Department of Pathology, University of Chicago, Chicago, IL
| | - Soma Das
- Department of Human Genetics, and
| | - Belinda R Avalos
- Department of Hematologic Oncology and Blood Disorders, Levine Cancer Institute, Atrium Health, Charlotte, NC; and
| | - Lucy A Godley
- Section of Hematology/Oncology, Department of Medicine, and
- University of Chicago Comprehensive Cancer Center, University of Chicago, Chicago, IL
- Department of Human Genetics, and
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Homology Modeling of an Alternative Splice Variant of Human Granulocyte Colony-Stimulating Factor, G-CSF Isoform D, and Study of Its Binding Properties by Molecular Docking. Int J Pept Res Ther 2020. [DOI: 10.1007/s10989-019-09814-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Katakura F, Nishiya K, Wentzel AS, Hino E, Miyamae J, Okano M, Wiegertjes GF, Moritomo T. Paralogs of Common Carp Granulocyte Colony-Stimulating Factor (G-CSF) Have Different Functions Regarding Development, Trafficking and Activation of Neutrophils. Front Immunol 2019; 10:255. [PMID: 30837998 PMCID: PMC6389648 DOI: 10.3389/fimmu.2019.00255] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 01/29/2019] [Indexed: 01/08/2023] Open
Abstract
Mammalian granulocyte colony-stimulating factor (G-CSF; CSF3) is a primary cytokine that promotes the development, mobilization, and activation of neutrophils and their precursors. Teleosts have been reported to possess two paralogs as a likely result of the teleost-wide whole genome duplication (WGD) event, but functional divergence of G-CSF paralogs remains poorly understood. Common carp are an allotetraploid species owing to an additional WGD event in the carp lineage and here, we report on genomic synteny, sequence similarity, and phylogeny of four common carp G-CSF paralogs (g-csfa1 and g-csfa2; g-csfb1 and g-csfb2). G-csfa1 and g-csfa2 show differential and relatively high gene expression levels, while g-csfb1 and g-csfb2 show low basal gene expression levels in most tissues. All paralogs are expressed higher in macrophages than in other leukocyte sub-types and are highly up-regulated by treatment of macrophages with mitogens. Recombinant G-CSFa1 and G-CSFb1 both promoted the proliferation of kidney hematopoietic cells, while only G-CSFb1 induced the differentiation of kidney cells along the neutrophil-lineage. Colony-forming unit assays revealed that G-CSFb1 alone stimulates the formation of CFU-G colonies from head- and trunk-kidney whereas the combination of G-CSFa1 and G-CSFb1 stimulates the formation of both CFU-G and CFU-GM colonies. Recombinant G-CSFa1 and G-CSFb1 also exhibit chemotactic activity against kidney neutrophils and up-regulation of cxcr1 mRNA expression was highest in neutrophils after G-CSFb1 stimulation. Furthermore, G-CSFb1 more than G-CSFa1 induced priming of kidney neutrophils through up-regulation of a NADPH-oxidase component p47 phox . In vivo administration of G-CSF paralogs increased the number of circulating blood neutrophils of carp. Our findings demonstrate that gene duplications in teleosts can lead to functional divergence between paralogs and shed light on the sub-functionalization of G-CSF paralogs in cyprinid fish.
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Affiliation(s)
- Fumihiko Katakura
- Laboratory of Comparative Immunology, Department of Veterinary Medicine, Nihon University, Fujisawa, Japan
| | - Kohei Nishiya
- Laboratory of Comparative Immunology, Department of Veterinary Medicine, Nihon University, Fujisawa, Japan
| | - Annelieke S. Wentzel
- Cell Biology and Immunology Group, Wageningen University & Research, Wageningen, Netherlands
| | - Erika Hino
- Laboratory of Comparative Immunology, Department of Veterinary Medicine, Nihon University, Fujisawa, Japan
| | - Jiro Miyamae
- Laboratory of Comparative Immunology, Department of Veterinary Medicine, Nihon University, Fujisawa, Japan
| | - Masaharu Okano
- Laboratory of Comparative Immunology, Department of Veterinary Medicine, Nihon University, Fujisawa, Japan
| | - Geert F. Wiegertjes
- Cell Biology and Immunology Group, Wageningen University & Research, Wageningen, Netherlands
- Aquaculture and Fisheries Group, Wageningen Institute of Animal Science, Wageningen University & Research, Wageningen, Netherlands
| | - Tadaaki Moritomo
- Laboratory of Comparative Immunology, Department of Veterinary Medicine, Nihon University, Fujisawa, Japan
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Siahmazgi MG, Khalili MAN, Ahmadpour F, Khodadadi S, Zeinoddini M. In Silico Design of Fusion Toxin DT 389GCSF and a Comparative Study. Curr Comput Aided Drug Des 2018; 16:238-244. [PMID: 30318000 DOI: 10.2174/1573409914666181012151242] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Revised: 09/27/2018] [Accepted: 10/06/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND Chemotherapy and radiotherapy have negative effects on normal tissues and they are very expensive and lengthy treatments. These disadvantages have recently attracted researchers to the new methods that specifically affect cancerous tissues and have lower damage to normal tissues. One of these methods is the use of intelligent recombinant fusion toxin. The fusion toxin DTGCSF, which consists of linked Diphtheria Toxin (DT) and Granulocyte Colony Stimulate Factor (GCSF), was first studied by Chadwick et al. in 1993 where HATPL linker provided the linking sequence between GCSF and the 486 amino acid sequences of DT. METHODS In this study, the fusion toxin DT389GCSF is evaluated for functional structure in silico. With the idea of the commercial fusion toxin of Ontak, the DT in this fusion protein is designed incomplete for 389 amino acids and is linked to the beginning of the GCSF cytokine via the SG4SM linker (DT389GCSF). The affinity of the DT389GCSF as a ligand with GCSF-R as receptor was compared with DT486GCSF as a ligand with GCSF-R as receptor. Both DT486GCSF and its receptor GCSF-R have been modeled by Easy Modeler2 software. Our fusion protein (DT389GCSF) and GCSF-R are modeled through Modeller software; all of the structures were confirmed by server MDWEB and VMD software. Then, the interaction studies between two proteins are done using protein-protein docking (HADDOCK 2.2 web server) for both the fusion protein in this study and DT486GCSF. RESULTS The HADDOCK results demonstrate that the interaction of DT389GCSF with GCSF-R is very different and has a more powerful interaction than DT486GCSF with GCSF-R. CONCLUSION HADDOCK web server is operative tools for evaluation of protein-protein interactions, therefore, in silico study of DT389GCSF will help with studying the function and the structure of these molecules. Moreover, DT389GCSF may have important new therapeutic applications.
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Affiliation(s)
| | | | - Fathollah Ahmadpour
- Trauma Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran
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Recombinant Filgrastim (BK0023) Pharmacodynamics and Pharmacokinetics After Single and Multiple Escalating Doses in an Equivalence Study in Healthy Men. Clin Drug Investig 2015; 35:533-45. [DOI: 10.1007/s40261-015-0310-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Fibroblast growth factor-peptide promotes bone marrow recovery after irradiation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012. [PMID: 22879028 DOI: 10.1007/978-1-4614-4989-8_22] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Various members of the fibroblast growth factor (FGF) family mitigate radiation-induced damage. We designed and synthesized the binding domain peptide of FGF-2 (FGF-P) with a dimer form resistant to peptidase and examined its mitigatory effect on murine bone marrow cells. NIH Swiss mice were exposed to different doses of total body irradiation (TBI) and treated with ten doses of 5 mg/kg FGF-P. We achieved the following results: (1) FGF-P stimulated the growth of bone marrow cells harvested from mice exposed to 3 Gy; (2) on day 25 after 6 Gy TBI, the number of leukocytes and granulocytes was higher in the FGF-P group than in the vehicle-alone group; (3) FGF-P significantly increased the number of pro-B and pre-B cells; and (4) FGF-P treatment in vivo increased the long-term hematopoietic stem cells (LT-HSC) in bone marrow. These data reveal the underlying mechanism by which FGF-P rescued a significant percentage of the exposed mice. The increase of LT-HSC in bone marrow leads to a concomitant increase of pro-B and pre-B cells followed by leukocytes and granulocytes, which in turn enhance immunity against infection.
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Sequential gain of mutations in severe congenital neutropenia progressing to acute myeloid leukemia. Blood 2012; 119:5071-7. [PMID: 22371884 DOI: 10.1182/blood-2012-01-406116] [Citation(s) in RCA: 136] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Severe congenital neutropenia (SCN) is a BM failure syndrome with a high risk of progression to acute myeloid leukemia (AML). The underlying genetic changes involved in SCN evolution to AML are largely unknown. We obtained serial hematopoietic samples from an SCN patient who developed AML 17 years after the initiation of G-CSF treatment. Next- generation sequencing was performed to identify mutations during disease progression. In the AML phase, we found 12 acquired nonsynonymous mutations. Three of these, in CSF3R, LLGL2, and ZC3H18, co-occurred in a subpopulation of progenitor cells already in the early SCN phase. This population expanded over time, whereas clones harboring only CSF3R mutations disappeared from the BM. The other 9 mutations were only apparent in the AML cells and affected known AML-associated genes (RUNX1 and ASXL1) and chromatin remodelers (SUZ12 and EP300). In addition, a novel CSF3R mutation that conferred autonomous proliferation to myeloid progenitors was found. We conclude that progression from SCN to AML is a multistep process, with distinct mutations arising early during the SCN phase and others later in AML development. The sequential gain of 2 CSF3R mutations implicates abnormal G-CSF signaling as a driver of leukemic transformation in this case of SCN.
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Jiang Y, Jiang W, Qiu Y, Dai W. Effect of a structurally modified human granulocyte colony stimulating factor, G-CSFa, on leukopenia in mice and monkeys. J Hematol Oncol 2011; 4:28. [PMID: 21668998 PMCID: PMC3130716 DOI: 10.1186/1756-8722-4-28] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 06/13/2011] [Indexed: 11/13/2022] Open
Abstract
Background Granulocyte colony stimulating factor (G-CSF) regulates survival, proliferation, and differentiation of neutrophilic granulocyte precursors, Recombinant G-CSF has been used for the treatment of congenital and therapy-induced neutropenia and stem cell mobilization. Due to its intrinsic instability, recombinant G-CSF needs to be excessively and/or frequently administered to patients in order to maintain a plasma concentration high enough to achieve therapeutic effects. Therefore, there is a need for the development of G-CSF derivatives that are more stable and active in vivo. Methods Using site-direct mutagenesis and recombinant DNA technology, a structurally modified derivative of human G-CSF termed G-CSFa was obtained. G-CSFa contains alanine 17 (instead of cysteine 17 as in wild-type G-CSF) as well as four additional amino acids including methionine, arginine, glycine, and serine at the amino-terminus. Purified recombinant G-CSFa was tested for its in vitro activity using cell-based assays and in vivo activity using both murine and primate animal models. Results In vitro studies demonstrated that G-CSFa, expressed in and purified from E. coli, induced a much higher proliferation rate than that of wild-type G-CSF at the same concentrations. In vivo studies showed that G-CSFa significantly increased the number of peripheral blood leukocytes in cesium-137 irradiated mice or monkeys with neutropenia after administration of clyclophosphamide. In addition, G-CSFa increased neutrophil counts to a higher level in monkeys with a concomitant slower declining rate than that of G-CSF, indicating a longer half-life of G-CSFa. Bone marrow smear analysis also confirmed that G-CSFa was more potent than G-CSF in the induction of granulopoiesis in bone marrows of myelo-suppressed monkeys. Conclusion G-CSFa, a structurally modified form of G-CSF, is more potent in stimulating proliferation and differentiation of myeloid cells of the granulocytic lineage than the wild-type counterpart both in vitro and in vivo. G-CSFa can be explored for the development of a new generation of recombinant therapeutic drug for leukopenia.
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11
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Huang YS, Wen XF, Wu YL, Wang YF, Fan M, Yang ZY, Liu W, Zhou LF. Engineering a pharmacologically superior form of granulocyte-colony-stimulating factor by fusion with gelatin-like-protein polymer. Eur J Pharm Biopharm 2009; 74:435-41. [PMID: 19995603 DOI: 10.1016/j.ejpb.2009.12.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 12/01/2009] [Accepted: 12/02/2009] [Indexed: 10/20/2022]
Abstract
The plasma half-life of therapeutic proteins is a critical factor in many clinical applications. Therefore, new strategies to prolong plasma half-life of long-acting peptides and protein drugs are in high demand. Here, we designed an artificial gelatin-like protein (GLK) and fused this hydrophilic GLK polymer to granulocyte-colony-stimulating factor (G-CSF) to generate a chimeric GLK/G-CSF fusion protein. The genetically engineered recombinant GLK/G-CSF (rGLK/G-CSF) fusion protein was purified from Pichia pastoris. In vitro studies demonstrated that rGLK/G-CSF possessed an enlarged hydrodynamic radius, improved thermal stability and retained full bioactivity compared to unfused G-CSF. Following a single subcutaneous administration to rats, the rGLK/G-CSF fusion protein displayed a slower plasma clearance rate and stimulated greater and longer lasting increases in circulating white blood cells than G-CSF. Our findings indicate that fusion with this artificial, hydrophilic, GLK polymer provides many advantages in the construction of a potent hematopoietic factor with extended plasma half-life. This approach could be easily applied to other therapeutic proteins and have important clinical applications.
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Affiliation(s)
- Yan-Shan Huang
- Department of Cell Biology, Zhejiang University, Hangzhou, China
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12
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Le Saux S, Rousseau F, Barbier F, Ravon E, Grimaud L, Danger Y, Froger J, Chevalier S, Gascan H. Molecular dissection of human interleukin-31-mediated signal transduction through site-directed mutagenesis. J Biol Chem 2009; 285:3470-7. [PMID: 19920145 DOI: 10.1074/jbc.m109.049189] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Interleukin (IL)-31 is a recently described cytokine, preferentially produced by T helper 2 lymphocytes and associated with skin diseases, such as atopic dermatitis. IL-31 is a member of the four alpha-helix bundle cytokine family and is related to the IL-6 subgroup. Its heterodimeric membrane receptor is composed of the gp130-like receptor (GPL) subunit associated to the oncostatin M receptor subunit. We identified critical amino acids implicated in the ligand receptor interaction by computational analysis combined with site-directed mutagenesis. Six IL-31 residues selected for their putative involvement in cytokine receptor contact sites were alanine-substituted, and the corresponding proteins were expressed in mammalian and bacterial systems. Biochemical, membrane binding, cell signaling, and cell proliferation analyses showed that mutation E44A, E106A, or H110A abolished IL-31 binding to GPL and the subsequent signaling events. A second ligand receptor-binding site involved Lys(134), with alanine substitution leading to a protein that still binds GPL, but is unable to recruit the second receptor subunit and the subsequent signaling pathways. The results indicate that IL-31 recognizes its receptor complex through two different binding sites, and we propose a three-dimensional model for IL-31.
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Affiliation(s)
- Sabine Le Saux
- Unité Mixte INSERM 564, Bâtiment Monteclair, 4 rue Larrey, 49933 Angers Cedex 09, France
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13
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Abstract
Recent structural information for complexes of cytokine receptor ectodomains bound to their ligands has significantly expanded our understanding of the macromolecular topology and ligand recognition mechanisms used by our three principal shared cytokine signaling receptors-gp130, gamma(c), and beta(c). The gp130 family receptors intricately coordinate three structurally unique cytokine-binding sites on their four-helix bundle cytokine ligands to assemble multimeric signaling complexes. These organizing principles serve as topological blueprints for the entire gp130 family of cytokines. Novel structures of gamma(c) and beta(c) complexes show us new twists, such as the use of a nonstandard sushi-type alpha receptors for IL-2 and IL-15 in assembling quaternary gamma(c) signaling complexes and an antiparallel interlocked dimer in the GM-CSF signaling complex with beta(c). Unlike gp130, which appears to recognize vastly different cytokine surfaces in chemically unique fashions for each ligand, the gamma(c)-dependent cytokines appear to seek out some semblance of a knobs-in-holes shape recognition code in order to engage gamma(c) in related fashions. We discuss the structural similarities and differences between these three shared cytokine receptors, as well as the implications for transmembrane signaling.
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Affiliation(s)
- Xinquan Wang
- Howard Hughes Medical Institute, Stanford University School of Medicine, Departments of Molecular and Cellular Physiology, and Structural Biology, Stanford, California 94305, USA.
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14
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Pharmacologic rationale for early G-CSF prophylaxis in cancer patients and role of pharmacogenetics in treatment optimization. Crit Rev Oncol Hematol 2008; 72:21-44. [PMID: 19111474 DOI: 10.1016/j.critrevonc.2008.10.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2008] [Revised: 10/14/2008] [Accepted: 10/22/2008] [Indexed: 11/22/2022] Open
Abstract
The use of recombinant human granulocyte colony stimulating factors (G-CSF) has become an integral part of supportive care during cytotoxic chemotherapy. Current guidelines recommend the use of G-CSF in patients with substantial risk of febrile neutropenia. However, little consensus exists about optimal timing and tailoring of this therapy. Based on the known effects of chemotherapy and G-CSF on bone marrow compartments, we propose a model that supports the prophylactic rather than therapeutic use of G-CSF therapy. In addition, several genetic alterations in G-CSF signalling pathway have been described. These genetic variants may predict the risk of febrile neutropenia and response to G-CSF. Thus, future pharmacogenetic/omics studies in this field are warranted. Through the identification of patients at risk and the knowledge of biological basis for optimal timing, hopefully we should soon be able to improve the application of the existing guidelines for G-CSF therapy and patient's prognosis.
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15
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Peelman F, Iserentant H, De Smet AS, Vandekerckhove J, Zabeau L, Tavernier J. Mapping of binding site III in the leptin receptor and modeling of a hexameric leptin.leptin receptor complex. J Biol Chem 2006; 281:15496-504. [PMID: 16540470 DOI: 10.1074/jbc.m512622200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The leptin.leptin receptor (LR) system shows strong similarities to the long chain cytokine interleukin-6 (IL-6) and granulocyte colony-stimulating factor (G-CSF) cytokine.cytokine receptor systems. The IL-6 family cytokines interact with their receptors through three different binding sites (I-III). We demonstrated previously that leptin has similar binding sites I-III and mapped the interactions between binding site II and cytokine receptor homology domain II (CRH2) (Peelman, F., Van Beneden, K., Zabeau, L., Iserentant, H., Ulrichts, P., Defeau, D., Verhee, A., Catteeuw, D., Elewaut, D., and Tavernier, J. (2004) J. Biol. Chem. 279, 41038-41046). In this study, we built homology models for the CRH1 and Ig-like domains of the LR. The Ig-like domain shows a large conserved surface patch in the beta-sheet formed by beta-strands 3, 6, and 7. Mutations in this patch almost completely abolished the leptin-induced STAT3-dependent reporter activity. We propose that a conserved cluster of residues Leu370, Ala407, Tyr409, His417, and His418 forms the center of binding site III of the LR. We built a hexameric leptin.LR complex model based on the hexameric IL-6 complex. In this model, a conserved hydrophobic protuberance of Val36, Thr37, Phe41, and Phe43 in the A-B loop of leptin fits perfectly in the CRH2 domain, corresponding to the IL-6 alpha-receptor, and forms the center of binding site I. The 2:4 hexameric leptin.LR complex offers a rational explanation for mutagenesis studies and residue conservation.
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Affiliation(s)
- Frank Peelman
- Department of Medical Protein Research, Flanders Interuniversity Institute for Biotechnology, Ghent, Belgium
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16
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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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17
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Honjo E, Tamada T, Maeda Y, Koshiba T, Matsukura Y, Okamoto T, Ishibashi M, Tokunaga M, Kuroki R. Crystallization of a 2:2 complex of granulocyte-colony stimulating factor (GCSF) with the ligand-binding region of the GCSF receptor. Acta Crystallogr Sect F Struct Biol Cryst Commun 2005; 61:788-90. [PMID: 16511159 PMCID: PMC1952362 DOI: 10.1107/s1744309105023080] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2005] [Accepted: 07/19/2005] [Indexed: 11/11/2022]
Abstract
The granulocyte-colony stimulating factor (GCSF) receptor receives signals for regulating the maturation, proliferation and differentiation of the precursor cells of neutrophilic granulocytes. The signalling complex composed of two GCSFs (GCSF, 19 kDa) and two GCSF receptors (GCSFR, 34 kDa) consisting of an Ig-like domain and a cytokine-receptor homologous (CRH) domain was crystallized. A crystal of the complex was grown in 1.0 M sodium formate and 0.1 M sodium acetate pH 4.6 and belongs to space group P4(1)2(1)2 (or its enantiomorph P4(3)2(1)2), with unit-cell parameters a = b = 110.1, c = 331.8 A. Unfortunately, this crystal form did not diffract beyond 5 A resolution. Since the heterogeneity of GCSF receptor appeared to prevent the growth of good-quality crystals, the GCSF receptor was fractionated by anion-exchange chromatography. Crystals of the GCSF-fractionated GCSF receptor complex were grown as a new crystal form in 0.2 M ammonium phosphate. This new crystal form diffracted to beyond 3.0 A resolution and belonged to space group P3(1)21 (or its enantiomorph P3(2)21), with unit-cell parameters a = b = 134.8, c = 105.7 A.
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Affiliation(s)
- Eijiro Honjo
- Pharmaceutical Research Laboratory, Kirin Brewery Co. Ltd, 3 Miyahara-cho, Takasaki 370-1295, Japan
| | - Taro Tamada
- Pharmaceutical Research Laboratory, Kirin Brewery Co. Ltd, 3 Miyahara-cho, Takasaki 370-1295, Japan
| | - Yoshitake Maeda
- Pharmaceutical Research Laboratory, Kirin Brewery Co. Ltd, 3 Miyahara-cho, Takasaki 370-1295, Japan
| | - Takumi Koshiba
- Central Laboratories for Key Technology, Kirin Brewery Co. Ltd, 1-13-5 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Yasuko Matsukura
- Pharmaceutical Research Laboratory, Kirin Brewery Co. Ltd, 3 Miyahara-cho, Takasaki 370-1295, Japan
| | - Tomoyuki Okamoto
- Pharmaceutical Research Laboratory, Kirin Brewery Co. Ltd, 3 Miyahara-cho, Takasaki 370-1295, Japan
| | - 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
- Pharmaceutical Research Laboratory, Kirin Brewery Co. Ltd, 3 Miyahara-cho, Takasaki 370-1295, Japan
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18
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Hermanns HM, Müller-Newen G, Heinrich PC, Haan S. Bow to your partner for signaling. Nat Struct Mol Biol 2005; 12:476-8. [PMID: 15933731 DOI: 10.1038/nsmb0605-476] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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19
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Iserentant H, Peelman F, Defeau D, Vandekerckhove J, Zabeau L, Tavernier J. Mapping of the interface between leptin and the leptin receptor CRH2 domain. J Cell Sci 2005; 118:2519-27. [PMID: 15923664 DOI: 10.1242/jcs.02386] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Despite the impact of the leptin system on body weight and other physiologic processes, little is known about the binding of leptin to its receptor. The extracellular domain of the leptin receptor consists of two cytokine receptor homology (CRH) domains separated by an immunoglobulin-like domain, and followed by two juxtamembrane fibronectin type III modules. The CRH2 domain functions as a high-affinity binding site for leptin, and we previously demonstrated interaction with helices A and C of leptin. In this work, we constructed a homology model for the leptin/CRH2 complex and performed a detailed mutation analysis of the CRH2/leptin interface. Using both cell-based and in vitro binding assays using the isolated CRH2 domain, we show the critical role of hydrophobic interactions between Leu 13 and Leu 86 of leptin and Leu 504 in CRH2 in leptin binding and signalling. This binding pattern closely resembles the interaction of other four-helix bundle long chain cytokines with the CRH domain of their cognate receptors.
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Affiliation(s)
- Hannes Iserentant
- Flanders Interuniversity Institute for Biotechnology, Department of Medical Protein Research (VIB09), Ghent University, Faculty of Medicine and Health Sciences, Baertsoenkaai 3, 9000 Ghent, Belgium
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20
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Arima K, Sato K, Tanaka G, Kanaji S, Terada T, Honjo E, Kuroki R, Matsuo Y, Izuhara K. Characterization of the interaction between interleukin-13 and interleukin-13 receptors. J Biol Chem 2005; 280:24915-22. [PMID: 15870068 DOI: 10.1074/jbc.m502571200] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Interleukin-13 (IL-13) possesses two types of receptor: the heterodimer, composed of the IL-13Ralpha1 chain (IL-13Ralpha1) and the IL-4Ralpha chain (IL-4Ralpha), transducing the IL-13 signals; and the IL-13Ralpha2 chain (IL-13Ralpha2), acting as a nonsignaling "decoy" receptor. Extracellular portions of both IL-13Ralpha1 and IL-13Ralpha2 are composed of three fibronectin type III domains, D1, D2, and D3, of which the last two comprise the cytokine receptor homology modules (CRHs), a common structure of the class I cytokine receptor superfamily. Thus far, there has been no information about the critical amino acids of the CRHs or the role of the D1 domains of IL-13Ralpha1 and IL-13Ralpha2 in binding to IL-13. In this study, we first built the homology modeling of the IL-13.hIL-13 receptor complexes and then predicted the amino acids involved in binding to IL-13. By incorporating mutations into these amino acids, we identified Tyr-207, Asp-271, Tyr-315, and Asp-318 in the CRH of human IL-13Ralpha2, and Leu-319 and Tyr-321 in the CRH of human IL-13Ralpha1, as critical residues for binding to IL-13. Tyr-315 in IL-13Ralpha2 and Leu-319 in IL-13Ralpha1 are positionally conserved hydrophobic amino acid residues. Furthermore, by using D1 domain-deleted mutants, we found that the D1 domain is needed for the expression of IL-13Ralpha2, but not IL-13Ralpha1, and that the D1 domain of IL-13Ralpha1 is important for binding to IL-13, but not to IL-4. These results provide the basis for a precise understanding of the interaction between IL-13 and its receptors.
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Affiliation(s)
- Kazuhiko Arima
- Division of Medical Biochemistry, Department of Biomolecular Sciences, Center for Comprehensive Community Medicine, Saga Medical School, Saga 849-8501, Japan
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21
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Boulanger MJ, Garcia KC. Shared cytokine signaling receptors: structural insights from the gp130 system. ACTA ACUST UNITED AC 2004; 68:107-46. [PMID: 15500860 DOI: 10.1016/s0065-3233(04)68004-1] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The vast majority of cytokine signaling is mediated by "shared" receptors that form central signaling components of higher-order complexes incorporating ligand-specific receptors. These include the common gamma chain (gamma(c)), common beta chain (beta(c)), and gp130, as well as others. These receptors have the dual tasks of cross-reactive cytokine recognition, and formation of precisely oriented multimeric signaling assemblies. Currently, detailed structural information on a shared receptor complex exists only for gp130, which is a highly pleiotropic shared cytokine signaling receptor essential for mammalian cell growth and homeostasis. To date, more than 10 different four-helix bundle ligands have been identified that incorporate gp130, or one of its close relatives such as LIF receptor, into functional oligomeric signaling complexes. In this review we summarize our current knowledge of shared receptor recognition and activation, with a focus on gp130. We discuss recent structural and functional information to analyze overall architectural assemblies of gp130 cytokine complexes and probe the basis for the extreme cross-reactivity of gp130 for its multiple cytokine ligands.
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Affiliation(s)
- Martin J Boulanger
- Department of Microbiology, Stanford University School of Medicine, Stanford, California 94305-5124, USA
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22
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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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23
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Peelman F, Van Beneden K, Zabeau L, Iserentant H, Ulrichts P, Defeau D, Verhee A, Catteeuw D, Elewaut D, Tavernier J. Mapping of the Leptin Binding Sites and Design of a Leptin Antagonist. J Biol Chem 2004; 279:41038-46. [PMID: 15213225 DOI: 10.1074/jbc.m404962200] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The leptin/leptin receptor system shows strong similarities to the long-chain cytokine interleukin-6 (IL-6) and granulocyte colony-stimulating factor cytokine/receptor systems. The IL-6 family cytokines interact with their receptors through three different binding sites I-III. The leptin structure was superposed on the crystal structures of several long-chain cytokines, and a series of leptin mutants was generated focusing on binding sites I-III. The effect of the mutations on leptin receptor (LR) signaling and on binding to the membrane proximal cytokine receptor homology domain (CRH2) of the LR was determined. Mutations in binding site I at the C terminus of helix D show a modest effect on signaling and do not affect binding to CRH2. Binding site II is composed of residues at the surface of helices A and C. Mutations in this site impair binding to CRH2 but have only limited effect on signaling. Site III mutations around the N terminus of helix D impair receptor activation without affecting binding to CRH2. We identified an S120A/T121A mutant in binding site III, which lacks any signaling capacity, but which still binds to CRH2 with wild type affinity. This leptin mutant behaves as a potent leptin antagonist both in vitro and in vivo.
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Affiliation(s)
- Frank Peelman
- Department of Medical Protein Research, Faculty of Medicine and Health Sciences, Flanders Interuniversity Institute for Biotechnology, VIB09, Ghent University, Albert Baertsoenkaai 3, Belgium
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24
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Mine S, Koshiba T, Honjo E, Okamoto T, Tamada T, Maeda Y, Matsukura Y, Horie A, Ishibashi M, Sato M, Azuma M, Tokunaga M, Nitta K, Kuroki R. Thermodynamic analysis of the activation mechanism of the GCSF receptor induced by ligand binding. Biochemistry 2004; 43:2458-64. [PMID: 14992583 DOI: 10.1021/bi0356855] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The granulocyte colony-stimulating factor receptor (GCSFR), containing the Ig-like domain (Ig) and cytokine receptor homologous region (CRH), was prepared as a preformed dimer (Ig-CRH-Fc)(2) after fusion to the mouse Fc region via an eight-residue linker (approximately 55 A). Monomer Ig-CRH was also prepared after the Fc region was removed from (Ig-CRH-Fc)(2). GCSF binding to Ig-CRH and (Ig-CRH-Fc)(2) was investigated using light scattering and isothermal titration calorimetry. The average molecular mass determined by light scattering showed that both Ig-CRH and (Ig-CRH-Fc)(2) formed a 2:2 dimer with GCSF. Moreover, isothermal titration calorimetry showed that the thermodynamic parameters upon binding of GCSF to Ig-CRH and (Ig-CRH-Fc)(2) were comparable, suggesting a similar binding stoichiometry and interface [including similar buried surface area (5700-6000 A(2))] despite the presence of the eight-residue linker. The buried surface area is much larger than that calculated from our previous report of the crystal structure of the GCSF-CRH complex [Aritomi, M., et al. (1999) Nature 401, 713-717], suggesting a substantial contribution of the Ig domain to GCSF binding. The data also indicate that the distance (55 A) between two CRH domains in the 2:2 complex is much shorter than in our previous model (approximately 90 A) predicted from the same crystal structure of the GCSF-CRH complex.
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Affiliation(s)
- Shouhei Mine
- Pharmaceutical Research Laboratories, Kirin Brewery Company Ltd., 3 Miyahara-cho, Takasaki 370-1295, Japan
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25
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Oshima Y, Tojo A, Fujimura A, Niho Y, Asano S. Potent receptor-mediated cytotoxicity of granulocyte colony-stimulating factor-Pseudomonas exotoxin, a fusion protein against myeloid leukemia cells. Biochem Biophys Res Commun 2004; 319:582-9. [PMID: 15178446 DOI: 10.1016/j.bbrc.2004.05.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2004] [Indexed: 11/16/2022]
Abstract
A chimeric toxin in which the cell-surface binding domain of Pseudomonas exotoxin A was replaced with mature human granulocyte colony-stimulating factor (G-CSF) was produced in Escherichia coli, purified and tested for its biological activity on the human G-CSF-responsive myeloid leukemia cell line, UT7/GR. This fusion protein, termed G-CSF-PE40, showed potent cytotoxicity in the cell line in a dose-dependent manner. G-CSF-PE40 displaced binding of biotinylated G-CSF to its receptor, and the cytotoxicity of G-CSF-PE40 was neutralized by an excess of wild-type G-CSF, indicating the receptor-mediated effects of this chimeric toxin. When G-CSF-PE40 was injected into normal mice, they showed transient neutropenia but no significant changes in the numbers of red blood cells or platelets. Furthermore, G-CSF-PE40 prolonged the survival of mice transplanted with syngeneic myeloid leukemia cells. These observations suggest that G-CSF-PE40 may be useful in targeted therapy of myeloid leukemia cells expressing G-CSF receptors.
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Affiliation(s)
- Yasuo Oshima
- Department of Hematology/Oncology, The Institutes of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
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26
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van de Geijn GJM, Aarts LHJ, Erkeland SJ, Prasher JM, Touw IP. Granulocyte colony-stimulating factor and its receptor in normal hematopoietic cell development and myeloid disease. Rev Physiol Biochem Pharmacol 2004; 149:53-71. [PMID: 12687405 DOI: 10.1007/s10254-003-0014-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Hematopoiesis, the process of blood cell formation, is orchestrated by cytokines and growth factors that stimulate the expansion of different progenitor cell subsets and regulate their survival and differentiation into mature blood cells. Granulocyte colony-stimulating factor (G-CSF) is the major hematopoietic growth factor involved in the control of neutrophil development. G-CSF is now applied on a routine basis in the clinic for treatment of congenital and acquired neutropenias. G-CSF activates a receptor of the hematopoietin receptor superfamily, the G-CSF receptor (G-CSF-R), which subsequently triggers multiple signaling mechanisms. Here we review how these mechanisms contribute to the specific responses of hematopoietic cells to G-CSF and how perturbations in the function of the G-CSF-R are implicated in various types of myeloid disease.
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Affiliation(s)
- G J M van de Geijn
- Department of Hematology, Erasmus University Medical Center, PO Box 1738, 3000 DR Rotterdam, The Netherlands
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27
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Zhu QS, Robinson LJ, Roginskaya V, Corey SJ. G-CSF-induced tyrosine phosphorylation of Gab2 is Lyn kinase dependent and associated with enhanced Akt and differentiative, not proliferative, responses. Blood 2003; 103:3305-12. [PMID: 14656892 DOI: 10.1182/blood-2003-06-1861] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The granulocyte colony-stimulating factor receptor (G-CSFR) transduces intracellular signals for myeloid cell proliferation, survival, and differentiation through the recruitment of nonreceptor protein tyrosine kinases Lyn and janus kinase 2 (Jak2). This results in the tyrosine phosphorylation of a small set of positive and negative adapters and effectors. Grb2-associated binder-2 (Gab2) is a newly described adapter molecule, preferentially expressed in hematopoietic cells and associated with phosphatidylinositol 3 (PI3) kinase. Studies suggest that Gab2 plays both positive and negative roles in cytokine receptor signaling. To investigate the role Gab2 plays in G-CSF receptor-mediated signaling, we have analyzed its activation state and correlated that with wild-type and mutant G-CSF receptors stably expressed in the murine factor-dependent Ba/F3 cell lines. G-CSF-induced tyrosine phosphorylation of Gab2 occurred in the wild-type and single Y-to-F mutants (Y704F, Y729F, and Y744F), but not in the ADA and W650R loss-of-function mutants. Cells expressing truncated proximal G-CSFR, the tyrosine-null (Y4F) G-CSFR, or Y764F mutant receptors had decreased phosphorylation of Gab2. Specific inhibitors of Src kinase (PD173 and PP1) but not Jak2 kinase (AG490) blocked Gab2 phosphorylation. Phosphorylation of Gab2 occurred in wild-type, but not Lyn-deficient, G-CSFR-transfected DT40 B cells. These data propose that Lyn, not Jak2, phosphorylates Gab2 and that maximal phosphorylation of Gab2 requires Y764, a Grb2-binding site. Serine phosphorylation of Akt, a marker of PI3-kinase activity, was detected in both wild-type and truncated proximal domain receptors, but not in the ADA and W650R mutants. Levels of phospho-Akt and phospho-extracellular signal-regulated kinase (phospho-ERK) were greater in proximal truncated than in wild-type G-CSFR cells, suggesting that Gab2 is dissociated from PI3 kinase or ERK activities. Overexpression of Gab2 enhanced the phosphorylation state of Akt, but not of ERK. This inhibited the proliferation of wild-type and truncated G-CSFR-transfected Ba/F3 cells and enhanced their myeloid differentiation. All together, these data indicate that G-CSF treatment leads to Lyn-mediated tyrosine phosphorylation of Gab2, which may serve as an important intermediate of enhanced Akt activity and myeloid differentiation, not growth/survival response.
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Affiliation(s)
- Quan-Sheng Zhu
- Division of Pediatrics, University of Texas M.D. Anderson Cancer, Houston, TX 77030, USA
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28
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Aarts LHJ, Roovers O, Ward AC, Touw IP. Receptor activation and 2 distinct COOH-terminal motifs control G-CSF receptor distribution and internalization kinetics. Blood 2003; 103:571-9. [PMID: 14512302 DOI: 10.1182/blood-2003-07-2250] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
We have studied the intracellular distribution and internalization kinetics of the granulocyte colony-stimulating factor receptor (G-CSF-R) in living cells using fusion constructs of wild-type or mutant G-CSF-R and enhanced green fluorescent protein (EGFP). Under steady-state conditions the G-CSF-R localized predominantly to the Golgi apparatus, late endosomes, and lysosomes, with only low expression on the plasma membrane, resulting from spontaneous internalization. Internalization of the G-CSF-R was significantly accelerated by addition of G-CSF. This ligand-induced switch from slow to rapid internalization required the presence of G-CSF-R residue Trp650, previously shown to be essential for its signaling ability. Both spontaneous and ligand-induced internalization depended on 2 distinct amino acid stretches in the G-CSF-R COOH-terminus: 749-755, containing a dileucine internalization motif, and 756-769. Mutation of Ser749 at position -4 of the dileucine motif to Ala significantly reduced the rate of ligand-induced internalization. In contrast, mutation of Ser749 did not affect spontaneous G-CSF-R internalization, suggesting the involvement of a serine-threonine kinase specifically in ligand-accelerated internalization of the G-CSF-R. COOH-terminal truncation mutants of G-CSF-R, found in severe congenital neutropenia, lack the internalization motifs and were completely defective in both spontaneous and ligand-induced internalization. As a result, these mutants showed constitutively high cell-surface expression.
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Affiliation(s)
- Lambertus H J Aarts
- Institute of Hematology, Erasmus University Medical Center, Rotterdam, The Netherlands
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Diveu C, Lelièvre E, Perret D, Lak-Hal AHL, Froger J, Guillet C, Chevalier S, Rousseau F, Wesa A, Preisser L, Chabbert M, Gauchat JF, Galy A, Gascan H, Morel A. GPL, a novel cytokine receptor related to GP130 and leukemia inhibitory factor receptor. J Biol Chem 2003; 278:49850-9. [PMID: 14504285 DOI: 10.1074/jbc.m307286200] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We describe a novel cytokine receptor named GP130 Like receptor, or GPL, that displays similarities with the interleukin-6 and interleukin-12 family of signaling receptors. Four different isoforms diverging in their carboxyl terminus were isolated, corresponding to proteins encompassing 560, 610, 626, and 745 amino acids. Sequences included a signal peptide of 32 amino acids, followed by a cytokine binding domain containing four conserved cysteines, a WSDWS motif, and a region consisting of three fibronectin type III domain repeats. No immunoglobulin-like module was identified in the GPL sequences. The intracellular part of longer isoforms contained a proline-rich region defining a box1 motif for interaction with the Janus kinases. The Gpl gene is organized in 15 exons and is located on 5q11.2 in tandem with the gp130 gene. Both genes were only separated by 24 kilobases, with opposite transcriptional orientations. The GPL receptor displayed a 28% identity with gp130. Specific GPL transcripts were observed in tissues involved in reproduction. Transcripts were also found in blood cells and in bone marrow, revealing expression of GPL in all of the myelomonocytic lineage, from hematopoietic stem cells to activated dendritic cells. In monocytes and dendritic cells, expression of GPL was strongly up-regulated by interferon-gamma, indicating a possible involvement of GPL in Th1-type immune responses. The molecular basis of cell signaling mediated by GPL was studied using chimeric receptors where external portions of alpha or beta interleukin-5 receptor subunits were fused to the internal portion of GPL or of related receptors. Results indicated that association of GPL to the intracellular portions of gp130, or LIF receptor, allowed the signaling cascade.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antigens, CD/chemistry
- Base Sequence
- COS Cells
- Chromosomes, Human, Pair 5
- Cloning, Molecular
- Cytokine Receptor gp130
- Cytokines/metabolism
- Cytoplasm/metabolism
- Dimerization
- Drosophila
- Exons
- Glycoside Hydrolases/metabolism
- Humans
- Interferon-gamma/metabolism
- Interleukin-12/metabolism
- Interleukin-5/metabolism
- Interleukin-6/metabolism
- Leukemia Inhibitory Factor Receptor alpha Subunit
- Membrane Glycoproteins/chemistry
- Models, Biological
- Molecular Sequence Data
- Peptides/chemistry
- Phylogeny
- Protein Isoforms
- Protein Structure, Tertiary
- RNA, Messenger/metabolism
- Receptors, Cytokine/chemistry
- Receptors, Cytokine/physiology
- Receptors, OSM-LIF
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Homology, Amino Acid
- Signal Transduction
- Th1 Cells/metabolism
- Tissue Distribution
- Transcription, Genetic
- U937 Cells
- Up-Regulation
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Plun-Favreau H, Perret D, Diveu C, Froger J, Chevalier S, Lelièvre E, Gascan H, Chabbert M. Leukemia inhibitory factor (LIF), cardiotrophin-1, and oncostatin M share structural binding determinants in the immunoglobulin-like domain of LIF receptor. J Biol Chem 2003; 278:27169-79. [PMID: 12707269 DOI: 10.1074/jbc.m303168200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Leukemia inhibitory factor (LIF), cardiotrophin-1 (CT-1), and oncostatin M (OSM) are four helix bundle cytokines acting through a common heterodimeric receptor composed of gp130 and LIF receptor (LIFR). Binding to LIFR occurs through a binding site characterized by an FXXK motif located at the N terminus of helix D (site III). The immunoglobulin (Ig)-like domain of LIFR was modeled, and the physico-chemical properties of its Connolly surface were analyzed. This analysis revealed an area displaying properties complementary to those of the LIF site III. Two residues of the Ig-like domain of LIFR, Asp214 and Phe284, formed a mirror image of the FXXK motif. Engineered LIFR mutants in which either or both of these two residues were mutated to alanine were transfected in Ba/F3 cells already containing gp130. The F284A mutation impaired the biological response induced by LIF and CT-1, whereas the response to OSM remained unchanged. The Asp214 mutation did not alter the functional responses. The D214A/F284A double mutation, however, totally impaired cellular proliferation to LIF and CT-1 and partially impaired OSM-induced proliferation with a 20-fold increase in EC50. These results were corroborated by the analysis of STAT3 phosphorylation and Scatchard analysis of cytokine binding to Ba/F3 cells. Molecular modeling of the complex of LIF with the Ig-like domain of LIFR provides a clue for the superadditivity of the D214A/F284A double mutation. Our results indicate that LIF, CT-1, and OSM share an overlapping binding site located in the Ig-like domain of LIFR. The different behaviors of LIF and CT-1, on one side, and of OSM, on the other side, can be related to the different affinity of their site III for LIFR.
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Affiliation(s)
- Hélène Plun-Favreau
- INSERM U564, Centre Hospitalier Universitaire d'Angers, 4 rue Larrey, 49033 Angers, France
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31
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Zabeau L, Lavens D, Peelman F, Eyckerman S, Vandekerckhove J, Tavernier J. The ins and outs of leptin receptor activation. FEBS Lett 2003; 546:45-50. [PMID: 12829235 DOI: 10.1016/s0014-5793(03)00440-x] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The adipocyte-derived hormone leptin signals the status of body energy stores by activating its receptor in hypothalamic nuclei. In contrast to the initial expectations, leptin treatment of human obesity was largely unsuccessful. One explanation for this is the marked leptin resistance, which likely operates in part at the receptor level. The leptin receptor is a member of the class I cytokine receptor family, which uses the Janus kinase/signal transducer and activator of transcription pathway as a major signaling route. In this review, we focus on the molecular mechanisms underlying leptin receptor activation. Different modes of leptin-induced clustering of the ectodomains and the subsequent signaling events will be discussed.
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Affiliation(s)
- Lennart Zabeau
- The Flanders Interuniversity Institute for Biotechnology, Department of Medical Protein Research (VIB9), Ghent University, Faculty of Medicine and Health Sciences, Baertsoenkaai 3, B-9000 Ghent, Belgium
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32
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Bitard J, Daburon S, Duplomb L, Blanchard F, Vuisio P, Jacques Y, Godard A, Heath JK, Moreau JF, Taupin JL. Mutations in the immunoglobulin-like domain of gp190, the leukemia inhibitory factor (LIF) receptor, increase or decrease its affinity for LIF. J Biol Chem 2003; 278:16253-61. [PMID: 12601009 DOI: 10.1074/jbc.m207193200] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The leukemia inhibitory factor (LIF) receptor comprises the low affinity binding chain gp190 and the high affinity converter gp130. The ectodomain of gp190 is among the most complex in the hematopoietin receptor family, because it contains two typical cytokine receptor homology domains separated by an immunoglobulin-like (Ig-like) domain. Human and murine gp190 proteins share 76% homology, but murine gp190 binds human LIF with a much higher affinity, a property attributed to the Ig-like domain. Using alanine-scanning mutagenesis of the Ig-like domain, we mapped a LIF binding site at its carboxyl terminus, mainly involving residue Phe-328. Mutation of selected residues into their orthologs in the murine receptor (Q251E and N321D) significantly increased the affinity for human LIF. Interestingly, these residues, although localized at both the amino and carboxyl terminus, make a spatially unique LIF binding site in a structural model of the Ig-like module. These results demonstrate definitively the role of the Ig-like domain in LIF binding and the potential to modulate receptor affinity in this family with very limited amino acid changes.
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Affiliation(s)
- Juliette Bitard
- CNRS UMR 5540, Université de Bordeaux 2, 146 rue Léo Saignat, 33076 Bordeaux, France
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33
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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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34
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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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