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Yu B, Sun W, Huang Z, Sun G, Li L, Gu J, Zheng M, Li X, Chun C, Hui Q, Wang X. Large-Scale Preparation of Highly Stable Recombinant Human Acidic Fibroblast Growth Factor in Escherichia coli BL21(DE3) plysS Strain. Front Bioeng Biotechnol 2021; 9:641505. [PMID: 33912546 PMCID: PMC8072344 DOI: 10.3389/fbioe.2021.641505] [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: 12/23/2020] [Accepted: 03/24/2021] [Indexed: 12/02/2022] Open
Abstract
In this study, the optimum human aFGF gene encoding haFGF135 was cloned in pET3c and transferred to Escherichia coli BL21(DE3) plysS. To enhance the yield of fermentation and the expression level of the target protein, the fermentation parameters, including temperature, pH, dissolved oxygen, glucose concentration, ammonium chloride concentration, induction time, and inducer (IPTG) concentration, were optimized. The optimized fermentation parameters were used in large-scale fermentation (30 L). Ion-exchange and heparin-affinity column chromatography techniques were used for separation and purification of rhaFGF135 protein. HPLC, isoelectric focusing electrophoresis, and mass spectrometry were used to detect the purity, isoelectric point, and molecular weight and peptide map of rhaFGF135 protein, respectively. Mitogenic activity of rhaFGF135 protein was detected in NIH-3T3 cells and a full-thickness injury wound diabetic rat model. The production and expression level of rhaFGF135 in the 30-L scale fermentation reached 80.4 ± 2.7 g/L culture and 37.8% ± 1.8%, respectively. The RP-HPLC and SDS-PAGE purity of the final rhaFGF135 product almost reached 100%, and the final pure protein yield was 158.6 ± 6.8 mg/L culture. Finally, the cell and animal experiments showed that rhaFGF135 retained a potent mitogenic activity. The large-scale process of rhaFGF135 production reported herein is relatively stable and time-saving, and thus, it can be used as an efficient and economic strategy for the synthesis of rhaFGF135 at the industrial level.
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Affiliation(s)
- Bingjieu Yu
- Wenzhou Medical University, Chashan University Park, Wenzhou, China
| | - Wenzhe Sun
- Wenzhou Medical University, Chashan University Park, Wenzhou, China
| | - Zhen Huang
- Wenzhou Medical University, Chashan University Park, Wenzhou, China
| | - Gang Sun
- Wenzhou Medical University, Chashan University Park, Wenzhou, China
| | - Le Li
- Wenzhou Medical University, Chashan University Park, Wenzhou, China
| | - Jiawei Gu
- Wenzhou Medical University, Chashan University Park, Wenzhou, China
| | - Mengying Zheng
- Wenzhou Medical University, Chashan University Park, Wenzhou, China
| | - Xiaokun Li
- Wenzhou Medical University, Chashan University Park, Wenzhou, China.,Engineering Laboratory of Zhejiang Province for Pharmaceutical Development of Growth Factors, Biomedical Collaborative Innovation Center of Wenzhou, Wenzhou, China
| | - ChangJu Chun
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Chonnam National University, Gwangju, South Korea
| | - Qi Hui
- Wenzhou Medical University, Chashan University Park, Wenzhou, China.,Engineering Laboratory of Zhejiang Province for Pharmaceutical Development of Growth Factors, Biomedical Collaborative Innovation Center of Wenzhou, Wenzhou, China
| | - Xiaojie Wang
- Wenzhou Medical University, Chashan University Park, Wenzhou, China.,Engineering Laboratory of Zhejiang Province for Pharmaceutical Development of Growth Factors, Biomedical Collaborative Innovation Center of Wenzhou, Wenzhou, China
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Chang CY, Lee KW, Wu CS, Huang YH, Chang HC, Chen CL, Li CT, Li MJ, Chang CF, Chen PW. Identification of sugar response complex in the metallothionein OsMT2b gene promoter for enhancement of foreign protein production in transgenic rice. PLANT CELL REPORTS 2019; 38:899-914. [PMID: 31004187 DOI: 10.1007/s00299-019-02411-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 04/12/2019] [Indexed: 06/09/2023]
Abstract
A 146-bp sugar response complex MTSRC is identified in the promoter of rice metallothionein OsMT2b gene conferring high-level expression of luciferase reporter gene and bioactive recombinant haFGF in transgenic rice. A rice subfamily type 2 plant metallothionein (pMT) gene, OsMT2b, encoding a reactive oxygen species (ROS) scavenger protein, has been previously shown to exhibit the most abundant gene expression in young rice seedling. Expression of OsMT2b was found to be regulated negatively by ethylene and hydrogen peroxide in rice stem node under flooding stress, but little is known about its response to sugar depletion. In this study, transient expression assay and transgenic approach were employed to characterize the regulation of the OsMT2b gene expression in rice. We found that the expression of OsMT2b gene is induced by sugar starvation in both rice suspension cells and germinated embryos. Deletion analysis and functional assay of the OsMT2b promoter revealed that the 5'-flanking region of the OsMT2b between nucleotides - 351 and - 121, which contains the sugar response complex (- 266 to - 121, designated MTSRC) is responsible for high-level promoter activity under sugar starvation. It was also found that MTSRC significantly enhances the Act1 promoter activity in transgenic rice cells and seedlings. The modified Act1 promoter, Act1-MTSRC, was used to produce the recombinant human acidic fibroblast growth factor (haFGF) in rice cells. Our result shows that the bioactive recombinant haFGF is stably produced in transformed rice cell culture and yields are up to 2% of total medium proteins. Our studies reveal that MTSRC serves as a strong transcriptional activator and the Act1-MTSRC promoter can be applicable in establishing an efficient expression system for the high-level production of foreign proteins in transgenic rice cells and seedlings.
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Affiliation(s)
- Chia-Yu Chang
- Department of BioAgricultural Sciences, National Chiayi University, Chiayi, 60004, Taiwan
| | - Kuo-Wei Lee
- Department of BioAgricultural Sciences, National Chiayi University, Chiayi, 60004, Taiwan
| | - Chung-Shen Wu
- Department of BioAgricultural Sciences, National Chiayi University, Chiayi, 60004, Taiwan
| | - Yu-Hsing Huang
- Department of BioAgricultural Sciences, National Chiayi University, Chiayi, 60004, Taiwan
| | - Ho-Chun Chang
- Department of BioAgricultural Sciences, National Chiayi University, Chiayi, 60004, Taiwan
| | | | - Chen-Tung Li
- PRIT Biotech Co., Ltd., Chunan, 35053, Miaoli, Taiwan
| | - Min-Jeng Li
- Department of BioAgricultural Sciences, National Chiayi University, Chiayi, 60004, Taiwan
| | - Chung-Fu Chang
- Department of BioAgricultural Sciences, National Chiayi University, Chiayi, 60004, Taiwan
| | - Peng-Wen Chen
- Department of BioAgricultural Sciences, National Chiayi University, Chiayi, 60004, Taiwan.
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Fabrication of the FGF1-functionalized sericin hydrogels with cell proliferation activity for biomedical application using genetically engineered Bombyx mori (B. mori) silk. Acta Biomater 2018; 79:239-252. [PMID: 30149211 DOI: 10.1016/j.actbio.2018.08.031] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 08/21/2018] [Accepted: 08/23/2018] [Indexed: 12/28/2022]
Abstract
Sericin, as the major component of Bombyx mori silk, is a useful biomaterial for tissue engineering due to its hydrophilicity, biocompatibility and biodegradability. Here, we report the fabrication of a human acidic fibroblast growth factor (FGF1)-functionalized sericin hydrogel using a transgenic silkworm spun silk with FGF1 incorporated in its sericin layer. Sericin, together with FGF1, were simultaneously extracted from the silk fiber and then exposed to cold-induced hydrogel formation without additional crosslinking. The fabricated FGF1 sericin hydrogels demonstrated injectability, useful mechanical properties and a porous microstructure, which contributed to cell adhesion and survival. In addition, FGF1 achieved long-term storage in the sericin hydrogels over a wide range of temperatures. Further, the sericin-FGF1 demonstrated sustained release to promote cell proliferation and wound healing. Furthermore, cellular inflammatory responses showed that the FGF1 sericin hydrogels exhibited biocompatibility and no immunogenicity. This study revealed the successful exploration of FGF1-functionalized sericin hydrogels as a new protein-based biomaterial to expand applications of FGF1 and sericin in tissue and medical engineering. Further, we demonstrated a strategy for the predesign of exogenous protein-functionalized sericin hydrogels through genetically modifying silk fibers as sources for their cost effective production at a large scale. STATEMENT OF SIGNIFICANCE Sericin from the Bombyx mori silk, is regarded as a desirable biomaterial for tissue engineering due to its hydrophilicity, biocompatibility and biodegradability. Genetically engineering the sericin with functional exogenous proteins would enhance its biofunctions and further expand its application in tissue engineering. In this study, we demonstrated a method to fabricate a human acidic fibroblast growth factor (FGF1)-functionalized sericin hydrogel using a transgenic silkworm spun silk with FGF1 incorporated in its sericin layer. The fabricated FGF1 sericin hydrogels demonstrated injectability, porous microstructure, biocompatibility and no immunogenicity which contributed to cell adhesion and survival. Remarkably, FGF1 could achieve a long-term stability in the sericin hydrogels over a wide range of temperatures and sustained release to promote cell proliferation and wound healing. This study revealed the successful exploration of FGF1-functionalized sericin hydrogels as a new protein-based biomaterial in tissue and medical engineering application, and provided a strategy for the predesign of exogenous protein-functionalized sericin hydrogels through genetically modifying silk fibers as sources for their cost effective production at a large scale.
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Stoykova P, Radkova M, Stoeva-Popova P, Atanasov N, Chassovnikarova T, Wang X, Iantcheva A, Vlahova M, Atanassov A. Expression of The Human Acidic Fibroblast Growth Factor in Transgenic Tomato and Safety Assessment of Transgenic Lines. BIOTECHNOL BIOTEC EQ 2014. [DOI: 10.5504/bbeq.2011.0021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Sletten T, Kostas M, Bober J, Sorensen V, Yadollahi M, Olsnes S, Tomala J, Otlewski J, Zakrzewska M, Wiedlocha A. Nucleolin regulates phosphorylation and nuclear export of fibroblast growth factor 1 (FGF1). PLoS One 2014; 9:e90687. [PMID: 24595027 PMCID: PMC3942467 DOI: 10.1371/journal.pone.0090687] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 02/04/2014] [Indexed: 11/19/2022] Open
Abstract
Extracellular fibroblast growth factor 1 (FGF1) acts through cell surface tyrosine kinase receptors, but FGF1 can also act directly in the cell nucleus, as a result of nuclear import of endogenously produced, non-secreted FGF1 or by transport of extracellular FGF1 via endosomes and cytosol into the nucleus. In the nucleus, FGF1 can be phosphorylated by protein kinase C δ (PKCδ), and this event induces nuclear export of FGF1. To identify intracellular targets of FGF1 we performed affinity pull-down assays and identified nucleolin, a nuclear multifunctional protein, as an interaction partner of FGF1. We confirmed a direct nucleolin-FGF1 interaction by surface plasmon resonance and identified residues of FGF1 involved in the binding to be located within the heparin binding site. To assess the biological role of the nucleolin-FGF1 interaction, we studied the intracellular trafficking of FGF1. In nucleolin depleted cells, exogenous FGF1 was endocytosed and translocated to the cytosol and nucleus, but FGF1 was not phosphorylated by PKCδ or exported from the nucleus. Using FGF1 mutants with reduced binding to nucleolin and a FGF1-phosphomimetic mutant, we showed that the nucleolin-FGF1 interaction is critical for the intranuclear phosphorylation of FGF1 by PKCδ and thereby the regulation of nuclear export of FGF1.
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Affiliation(s)
- Torunn Sletten
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Norway
| | - Michal Kostas
- Department of Protein Biotechnology, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Joanna Bober
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Vigdis Sorensen
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Norway
| | - Mandana Yadollahi
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Norway
| | - Sjur Olsnes
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Norway
| | - Justyna Tomala
- Department of Protein Biotechnology, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Jacek Otlewski
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Malgorzata Zakrzewska
- Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
| | - Antoni Wiedlocha
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Norway
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Matsuo K, Hong JS, Tabayashi N, Ito A, Masuta C, Matsumura T. Development of Cucumber mosaic virus as a vector modifiable for different host species to produce therapeutic proteins. PLANTA 2007; 225:277-86. [PMID: 16821041 DOI: 10.1007/s00425-006-0346-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Accepted: 06/09/2006] [Indexed: 05/10/2023]
Abstract
We have developed Cucumber mosaic virus (CMV) as a plant virus vector especially for production of pharmaceutical proteins. The CMV vector is a vector modifiable for different host plants and does not require further engineering steps. CMV contains three genomic RNA molecules (RNAs 1-3) necessary for infectivity. With this system, instead of creating different vector constructs for each plant we use, we take advantage of the formation of pseudrecombinants between two CMV isolates by simply reassembling a vector construct (RNA 2 base) and an RNA molecule containing the host determinant (mostly RNA 3). In this study, the gene for acidic fibroblast growth factor (aFGF), one of the human cytokines, was cloned under the control of the subgenomic promoter for RNA 4A of the CMV-based vector, C2-H1. Infected Nicotiana benthamiana plants produced aFGF at levels up to 5-8% of the total soluble protein. The tobacco-produced aFGF was purified, and its biological activity was confirmed. Using this system, which provides a versatile and viable strategy for the production of therapeutic proteins in plants, we also demonstrated a high level of aFGF in Glycine max (soybean) and Arabidopsis thaliana.
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Affiliation(s)
- Kouki Matsuo
- National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Sapporo, Japan
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Volkin DB, Middaugh CR. The characterization, stabilization, and formulation of acidic fibroblast growth factor. PHARMACEUTICAL BIOTECHNOLOGY 2002; 9:181-217. [PMID: 8914192 DOI: 10.1007/0-306-47452-2_3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- D B Volkin
- Department of Vaccine Pharmaceutical Research, Merck Research Laboratories, West Point, Pennsylvania 19486, USA
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Chamberlain CG, McAvoy JW. Fibre differentiation and polarity in the mammalian lens: a key role for FGF. Prog Retin Eye Res 1997. [DOI: 10.1016/s1350-9462(96)00034-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Mühlhauser J, Pili R, Merrill MJ, Maeda H, Passaniti A, Crystal RG, Capogrossi MC. In vivo angiogenesis induced by recombinant adenovirus vectors coding either for secreted or nonsecreted forms of acidic fibroblast growth factor. Hum Gene Ther 1995; 6:1457-65. [PMID: 8573618 DOI: 10.1089/hum.1995.6.11-1457] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
In vivo gene transfer of angiogenic growth factors represents a potential approach to the treatment of ischemic diseases. The present study examined the in vitro and in vivo effects of two replication-deficient recombinant adenovirus (Ad) vectors coding for human acidic fibroblast growth factor (aFGF1-154). One vector codes for the nonsecreted form of the peptide (AdCMV.aFGF1-154), and the other vector codes for a recombinant, secreted form (AdCMV.sp+aFGF1-154). AdCMV.NLS beta gal, an adenovirus vector coding for beta-galactosidase (beta-Gal), was used as a control. Assessment of proliferation of starved human umbilical vein endothelial cells infected with AdCMV.aFGF1-154 and AdCMV.sp+aFGF1-154 (20 pfu/cell) showed approximately 6- and 10-fold increase in cell number over control, respectively. Infection with AdCMV.sp+aFGF1-154 and with AdCMV.aFGF1-154 enhanced endothelial cell differentiation into capillary-like structures in vitro. However, this effect was significantly more pronounced with AdCMV.sp+aFGF1-154 than with AdCMV.aFGF1-154. Angiogenesis in vivo was assessed by injecting subcutaneously into mice 750 microliters of reconstituted basement membrane proteins (Matrigel) and the Ad vectors (2 x 10(8) pfu). After 14 days, there was histologic evidence of neovascularization in the animal's tissue surrounding the Matrigel plugs with AdCMV.aFGF1-154 and AdCMV.sp+aFGF1-154. Further, the hemoglobin content of the Matrigel plugs with AdCMV.aFGF1-154 and with AdCMV.sp+aFGF1-154 was, respectively, 2.3- and 2.6-fold higher than with AdCMV.NLS beta gal. Together, these observations support the concept that adenovirus vectors coding for various forms of acidic FGF1-154 may be used to induce angiogenesis in vivo and may provide a new therapeutic approach to ischemic diseases.
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Affiliation(s)
- J Mühlhauser
- Gene Therapy Unit, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
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10
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Nham SU, Kim HS, Lee YI. Overexpression and purification of full-length acidic fibroblast growth factor inE.coli. Biotechnol Lett 1994. [DOI: 10.1007/bf00136467] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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11
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Manske M, Bade EG. Growth factor-induced cell migration: biology and methods of analysis. INTERNATIONAL REVIEW OF CYTOLOGY 1994; 155:49-96. [PMID: 7860215 DOI: 10.1016/s0074-7696(08)62096-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- M Manske
- Arbeitsgruppe Zellbiologie-Tumorbiologie, Fakultät für Biologie, Universität Konstanz, Germany
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12
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Volkin DB, Verticelli AM, Marfia KE, Burke CJ, Mach H, Middaugh CR. Sucralfate and soluble sucrose octasulfate bind and stabilize acidic fibroblast growth factor. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1203:18-26. [PMID: 7692970 DOI: 10.1016/0167-4838(93)90031-l] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The actions of the anti-ulcer drug sucralfate have been proposed to be mediated through interaction with fibroblast growth factors (Folkman, J., Szabo, S., Strovroff, M., McNeil, P., Li, W. and Shing, Y. (1991) Ann. Surg. 214, 414-427). We show here that acidic fibroblast growth factor (aFGF; FGF-1) binds in vitro to both the soluble potassium salt and the insoluble aluminum salt of sucrose octasulfate, as demonstrated by a variety of biophysical techniques. Similar to the well-described interaction and stabilization of aFGF by heparin, soluble sucrose octasulfate (SOS) stabilizes aFGF against thermal, urea and acidic pH-induced unfolding as determined by a combination of circular dichroism, fluorescence spectroscopy and differential scanning calorimetry. In addition, SOS also enhances the mitogenic activity of aFGF and partially protects the protein's three cysteine residues from copper-catalyzed oxidation. SOS competes with heparin and suramin for the aFGF polyanion binding site as measured by both fluorescence and light scattering based competitive binding assays. Front-face fluorescence measurements show that the native, folded form of aFGF binds to the insoluble aluminum salt of sucrose octasulfate (sucralfate). Moreover, sucralfate stabilizes aFGF against thermal and acidic pH-induced unfolding to the same extent as observed with SOS. Thus, due to their high charge density, SOS and sucralfate bind and stabilize aFGF via interaction with the aFGF polyanion binding site.
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Affiliation(s)
- D B Volkin
- Department of Pharmaceutical Research, Merck Research Laboratories, West Point, PA 19486
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Burke CJ, Volkin DB, Mach H, Middaugh CR. Effect of polyanions on the unfolding of acidic fibroblast growth factor. Biochemistry 1993; 32:6419-26. [PMID: 7686045 DOI: 10.1021/bi00076a015] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The urea-induced unfolding of acidic fibroblast growth factor (aFGF) in the presence and absence of various polyanions has been quantitatively examined by fluorescence spectroscopy. In the absence of a stabilizing polyanion, the apparent free energy of unfolding of aFGF is 6.5 kcal mol-1. The presence of equimolar or greater amounts of heparin stabilizes aFGF from unfolding by more than 2.5 kcal mol-1 and slows the rate of unfolding by greater than 2000-fold. The ability of heparin to stabilize aFGF is critically dependent upon many factors including the number of aFGF molecules bound to the heparin chain, ionic strength, temperature, and the extent of sulfation of the polysaccharide. The presence of similar amounts of other polyanions such as sulfated beta-cyclodextrin or heparan sulfate also stabilizes aFGF to a similar extent as heparin. Additional experiments demonstrate that increasing charge density enhances the ability of polyanions such as sulfated beta-cyclodextrins, phosphorylated inositols, and modified heparins to protect aFGF from urea-induced unfolding.
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Affiliation(s)
- C J Burke
- Department of Pharmaceutical Research, Merck Research Laboratories, West Point, Pennsylvania 19486
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Tsai PK, Volkin DB, Dabora JM, Thompson KC, Bruner MW, Gress JO, Matuszewska B, Keogan M, Bondi JV, Middaugh CR. Formulation design of acidic fibroblast growth factor. Pharm Res 1993; 10:649-59. [PMID: 7686672 DOI: 10.1023/a:1018939228201] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The design of an aqueous formulation for acidic fibroblast growth factor (aFGF) requires an understanding of the type of compounds that can either directly or indirectly stabilize the protein. To this end, spectrophotometric turbidity measurements were initially employed to screen the ability of polyanionic ligands, less specific compounds, and variations in solution conditions (temperature and pH) to stabilize aFGF against heat-induced aggregation. It was found that in addition to the well-known protection of aFGF by heparin, a surprisingly wide variety of polyanions (including small sulfated and phosphorylated compounds) also stabilizes aFGF. These polyanionic ligands are capable of raising the temperature at which the protein unfolds by 15-30 degrees C. Many commonly used excipients were also observed to stabilize aFGF in both the presence and the absence of heparin. High concentrations of some of these less specific agents are also able to increase the temperature of aFGF thermal unfolding by as much as 6-12 degrees C as shown by circular dichroism and differential scanning calorimetry. Other compounds were found which protect the chemically labile cysteine residues of aFGF from oxidation. Aqueous formulations of aFGF were thus designed to contain both a polyanionic ligand that enhances structural integrity by binding to the protein and chelating agents (e.g., EDTA) to prevent metal ion-catalyzed oxidation of cysteine residues. While room-temperature storage (30 degrees C) leads to rapid inactivation of aFGF in physiological buffer alone, several of these aFGF formulations are stable in vitro for at least 3 months at 30 degrees C. Three aFGF topical formulations were examined in an impaired diabetic mouse model and were found to be equally capable of accelerating wound healing.
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Affiliation(s)
- P K Tsai
- Department of Pharmaceutical Research, Merck Research Laboratory, West Point, Pennsylvania 19486
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15
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Schulz MW, Chamberlain CG, de Iongh RU, McAvoy JW. Acidic and basic FGF in ocular media and lens: implications for lens polarity and growth patterns. Development 1993; 118:117-26. [PMID: 7690700 DOI: 10.1242/dev.118.1.117] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have shown previously that FGF induces lens epithelial cells in explant culture to proliferate, migrate and differentiate into fibre cells in a progressive concentration-dependent manner. In situ, these processes occur in a distinct anterior-posterior pattern in clearly defined regions of the lens. Thus anterior-posterior differences in the bio-availability of FGF in the lens environment may play a role in determining lens polarity and growth patterns. In this study, using heparin chromatography and western blotting (or ELISA), we established that both acidic and basic FGF are present in the aqueous and vitreous (the ocular media that bathe the anterior and posterior compartments of the lens, respectively). In addition, substantially more FGF was recovered from vitreous than from aqueous. Both forms of FGF were also detected in lens fibre cells and capsule. A truncated form of basic FGF (less than 20 × 10(3) M(r)) predominated in every case with traces of higher M(r) forms in lens cells. For acidic FGF, the classical full-length form (about 20 × 10(3) M(r)) predominated in lens cells and a truncated form was found in vitreous. The capsule contained a higher M(r) form. Using our explant system, we also tested the biological activity of ocular media and FGF fractions obtained from vitreous and lens cells. Vitreous but not aqueous contained fibre-differentiating activity. Furthermore, virtually all the fibre-differentiating activity of vitreous was shown to be FGF-associated, as follows: (a) this activity remained associated with FGF during fractionation of vitreous by heparin and Mono-S chromatography and (b) the activity of the major FGF-containing fraction was blocked by antibodies to acidic and basic FGF. Posterior, but not anterior, capsule was shown to have mitogenic activity, which was neutralised by FGF antibodies and associated only with the cellular surface. These results support our hypothesis that FGF is involved in determining the behaviour of lens cells in situ. In particular, a key role for FGF in determining lens polarity and growth patterns is suggested by the anterior-posterior differences in the bio-availability of FGF in the ocular media and capsule.
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Affiliation(s)
- M W Schulz
- Department of Anatomy and Histology, University of Sydney, NSW Australia
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