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Abstract
Introduction: PEGylation is a well-established technology for improving the therapeutic value of drugs by attaching polyethylene glycol (PEG). The first PEGylated enzyme products appeared on the market in the early 1990s; currently, more than 18 PEGylated products have been approved by Food and Drug Administration, which encompass various classes of drug molecules, such as enzymes, interferons, granulocyte colony-stimulating factors, hormones, antibody fragments, coagulation factors, oligonucleotide aptamers, synthetic peptides, and small organic molecules. Areas covered: While PEGylated products mainly comprise biologic drugs, such as recombinant proteins and enzymes, non-biologic drugs have recently emerged as a target for PEGylation. This review focuses on the recent development of PEGylated non-biologic drugs, such as small organic molecules, synthetic peptides, and aptamers. Expert opinion: Several PEGylated versions of anti-cancer drugs, opioid agonists, glucagon-like peptide-1 receptor agonists, and oligonucleotide aptamers are in active development stage, and it is likely that they will have a dramatic impact on the market. Although some safety concerns about PEG in clinical trials have been recently issued, PEGylation is still a commercially attractive proposition as a half-life extension technology for long-acting drug development.
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Affiliation(s)
- Eun Ji Park
- a College of Pharmacy , Chung-Ang University , Seoul , Republic of Korea.,b D&D Pharmatech , Seongnam , Republic of Korea
| | - Jiyoung Choi
- a College of Pharmacy , Chung-Ang University , Seoul , Republic of Korea
| | - Kang Choon Lee
- b D&D Pharmatech , Seongnam , Republic of Korea.,c College of Pharmacy , SungKyunKwan University , Suwon , Republic of Korea
| | - Dong Hee Na
- a College of Pharmacy , Chung-Ang University , Seoul , Republic of Korea
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2
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Park EJ, Na DH. Characterization of the Reversed-Phase Chromatographic Behavior of PEGylated Peptides Based on the Poly(ethylene glycol) Dispersity. Anal Chem 2016; 88:10848-10853. [DOI: 10.1021/acs.analchem.6b03577] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eun Ji Park
- College of Pharmacy and Research
Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Dong Hee Na
- College of Pharmacy and Research
Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 41566, Republic of Korea
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3
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Abstract
PEGylation is the covalent conjugation of PEG to therapeutic molecules. Protein PEGylation is a clinically proven approach for extending the circulation half-life and reducing the immunogenicity of protein therapeutics. Most clinically used PEGylated proteins are heterogeneous mixtures of PEG positional isomers conjugated to different residues on the protein main chain. Current research is focused to reduce product heterogeneity and to preserve bioactivity. Recent advances and possible future directions in PEGylation are described in this review. So far protein PEGylation has yielded more than 10 marketed products and in view of the lack of equally successful alternatives to extend the circulation half-life of proteins, PEGylation will still play a major role in drug delivery for many years to come.
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González M, Ceaglio NA, de los Milagros Bürgi M, Etcheverrigaray M, Kratje RB, Vaillard SE. Novel reactive PEG for amino group conjugation. RSC Adv 2015. [DOI: 10.1039/c5ra00758e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Activated mPEG carbonates are important reagents that have been widely used for the PEGylation of several peptides and proteins by means of stable urethane linkages.
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Affiliation(s)
- Marianela González
- Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
- CCT Santa Fe CONICET-UNL
- Colectora Ruta Nacional 168
- Santa Fe
- Argentina
| | - Natalia A. Ceaglio
- Laboratorio de Cultivos Celulares
- Facultad de Bioquímica y Ciencias Biológicas
- Universidad Nacional del Litoral
- Ciudad Universitaria
- Santa Fe
| | - M. de los Milagros Bürgi
- Laboratorio de Cultivos Celulares
- Facultad de Bioquímica y Ciencias Biológicas
- Universidad Nacional del Litoral
- Ciudad Universitaria
- Santa Fe
| | - Marina Etcheverrigaray
- Laboratorio de Cultivos Celulares
- Facultad de Bioquímica y Ciencias Biológicas
- Universidad Nacional del Litoral
- Ciudad Universitaria
- Santa Fe
| | - Ricardo B. Kratje
- Laboratorio de Cultivos Celulares
- Facultad de Bioquímica y Ciencias Biológicas
- Universidad Nacional del Litoral
- Ciudad Universitaria
- Santa Fe
| | - Santiago E. Vaillard
- Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
- CCT Santa Fe CONICET-UNL
- Colectora Ruta Nacional 168
- Santa Fe
- Argentina
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5
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Choubey AK, Dora CP, Bhatt TD, Gill MS, Suresh S. Development and evaluation of PEGylated Enoxaparin: A novel approach for enhanced anti-Xa activity. Bioorg Chem 2014; 54:1-6. [DOI: 10.1016/j.bioorg.2014.03.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 02/26/2014] [Accepted: 03/03/2014] [Indexed: 11/25/2022]
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6
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Yang Y, Bhandari KH, Panahifar A, Doschak MR. Synthesis, characterization and biodistribution studies of (125)I-radioiodinated di-PEGylated bone targeting salmon calcitonin analogue in healthy rats. Pharm Res 2013; 31:1146-57. [PMID: 24357414 DOI: 10.1007/s11095-013-1237-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 10/20/2013] [Indexed: 10/25/2022]
Abstract
PURPOSE The objective of this study was to prepare a bisphosphonate (BP) mediated bone targeting di-PEGylated salmon calcitonin analogue sCT-2(PEG-BP) as a novel bone targeting pharmaceutical. METHODS HPLC was used for isolation of sCT-2(PEG-BP) from the reaction mixture, followed by determination of possible PEGylation sites by trypsin digestion. Stability of the compound over time, bone mineral affinity using hydroxyapatite, and biodistribution in normal rats after radiolabeling of sCT-2(PEG-BP) or control sCT with (125)I was evaluated. RESULTS PEGylated sCT analogues were synthesized, and sCT-2(PEG-BP) was isolated by HPLC and confirmed by MALDI-TOF and ICP-MS. MALDI-TOF analysis of trypsinized fragments suggested Cys(1) (or Lys(11)) and Lys(18) to be the two PEGylation sites. Bone mineral affinity test showed sCT-2(PEG-BP) or (125)I-sCT-2(PEG-BP) exhibited significantly increased bone mineral affinity over sCT or (125)I-sCT, respectively. sCT-2(PEG-BP) remained stable for at least 1 month. In vivo biodistribution study showed significantly increased bone retention and prolonged plasma circulation time for sCT-2(PEG-BP) compared to the control sCT. CONCLUSION Those results support sCT-2(PEG-BP) as a promising new drug candidate for the treatment of resorptive and/or maladaptive bone conditions, such as Osteoporosis, Osteoarthritis, Rheumatoid Arthritis, Paget's disease and bone cancers.
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Affiliation(s)
- Yang Yang
- Pharmaceutical Orthopaedic Research Laboratory Faculty of Pharmacy & Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2E1, Canada
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Forstenlehner IC, Holzmann J, Scheffler K, Wieder W, Toll H, Huber CG. A direct-infusion- and HPLC-ESI-Orbitrap-MS approach for the characterization of intact PEGylated proteins. Anal Chem 2013; 86:826-34. [PMID: 24308604 DOI: 10.1021/ac403390y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The characterization of proteins modified with poly(ethylene glycol) (PEG), such as recombinant human granulocyte-colony stimulating factor (PEGylated rhG-CSF or pegfilgrastim), by electrospray ionization-mass spectrometry (ESI-MS) constitutes a challenge due to the overlapping protein charge state pattern and PEG polydispersity. In order to minimize spectral overlaps, charge reduction by means of the addition of amine was applied. Method development for direct-infusion measurements, carried out on an ESI-time-of-flight (ESI-TOF) instrument, demonstrated the potential of triethylamine (TEA) for shifting the charge state pattern toward lower-charged species and of formic acid (FA) for causing higher charging. After successful method transfer to the LTQ Orbitrap XL instrument, isotopically resolved mass spectra could be acquired. With a median mass accuracy of 1.26 ppm, a number-average monoisotopic molecular mass of 40074.64 Da was determined for pegfilgrastim. The direct comparison of three Orbitrap mass spectrometers, namely the LTQ Orbitrap XL, the Exactive, and the Q Exactive, demonstrated that online interfacing to high performance liquid chromatography (HPLC) was only feasible with the Q Exactive, which offers adequate spectral quality on a time scale compatible with chromatographic separation (i.e., 0.2 min acquisition time per chromatographic peak). Finally, the applicability of both direct-infusion Orbitrap MS and HPLC interfaced to Orbitrap MS was demonstrated for the detection of methionine oxidation in pegfilgrastim. Singly, doubly, and triply oxidized species were readily resolved in the chromatogram, while their oxidation status was easily determined from the mass shifts observed in the deconvoluted mass spectra.
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Affiliation(s)
- Ines C Forstenlehner
- Department of Molecular Biology, Division of Chemistry and Bioanalytics, University of Salzburg , Hellbrunnerstrasse 34, 5020 Salzburg, Austria
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Determination of the molecular weight of poly(ethylene glycol) in biological samples by reversed-phase LC–MS with in-source fragmentation. Anal Bioanal Chem 2013; 405:4283-7. [DOI: 10.1007/s00216-013-6795-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 01/22/2013] [Accepted: 01/25/2013] [Indexed: 10/27/2022]
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9
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Structural stability–chromatographic retention relationship on exenatide diastereomer separation. Anal Bioanal Chem 2012; 404:2437-44. [DOI: 10.1007/s00216-012-6352-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 08/03/2012] [Accepted: 08/13/2012] [Indexed: 10/27/2022]
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10
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Jones MW, Mantovani G, Blindauer CA, Ryan SM, Wang X, Brayden DJ, Haddleton DM. Direct peptide bioconjugation/PEGylation at tyrosine with linear and branched polymeric diazonium salts. J Am Chem Soc 2012; 134:7406-13. [PMID: 22494012 DOI: 10.1021/ja211855q] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Direct polymer conjugation at peptide tyrosine residues is described. In this study Tyr residues of both leucine enkephalin and salmon calcitonin (sCT) were targeted using appropriate diazonium salt-terminated linear monomethoxy poly(ethylene glycol)s (mPEGs) and poly(mPEG) methacrylate prepared by atom transfer radical polymerization. Judicious choice of the reaction conditions-pH, stoichiometry, and chemical structure of diazonium salt-led to a high degree of site-specificity in the conjugation reaction, even in the presence of competitive peptide amino acid targets such as histidine, lysines, and N-terminal amine. In vitro studies showed that conjugation of mPEG(2000) to sCT did not affect the peptide's ability to increase intracellular cAMP induced in T47D human breast cancer cells bearing sCT receptors. Preliminary in vivo investigation showed preserved ability to reduce [Ca(2+)] plasma levels by mPEG(2000)-sCT conjugate in rat animal models.
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Affiliation(s)
- Mathew W Jones
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK
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11
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In Vitro and In Vivo Characterisation of PEG-Lipid-Based Micellar Complexes of Salmon Calcitonin for Pulmonary Delivery. Pharm Res 2012; 29:1425-34. [DOI: 10.1007/s11095-012-0688-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Accepted: 01/17/2012] [Indexed: 11/26/2022]
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Cheng TL, Chuang KH, Chen BM, Roffler SR. Analytical Measurement of PEGylated Molecules. Bioconjug Chem 2012; 23:881-99. [DOI: 10.1021/bc200478w] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tian-Lu Cheng
- Department of Biomedical Science
and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Kuo-Hsiang Chuang
- Department of Biomedical Science
and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Bing-Mae Chen
- Institute
of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Steve R. Roffler
- Institute
of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
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Mero A, Clementi C, Veronese FM, Pasut G. Covalent conjugation of poly(ethylene glycol) to proteins and peptides: strategies and methods. Methods Mol Biol 2011; 751:95-129. [PMID: 21674328 DOI: 10.1007/978-1-61779-151-2_8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
PEGylation, the covalent linking of PEG chains, has become the leading drug delivery approach for proteins. This technique initiated its first steps almost 40 years ago, and since then, a variety of methods and strategies for protein-polymer coupling have been devised. PEGylation can give a number of relevant advantages to the conjugated protein, such as an important in vivo half-life prolongation, a reduction or an abolishment of immunogenicity, and a reduction of aggregation. Furthermore, the technique has demonstrated a great degree of versatility and efficacy--not only PEG-protein conjugates have reached the commercial marketplace (with nine types of derivatives), but a PEG-aptamer and PEGylated liposomes are now also available. Most of this success is due to the development of several PEGylation strategies and to the large selection of PEGylating agents presently at hand for researchers. Nevertheless, this technique still requires a certain level of familiarity and knowledge in order to achieve a positive outcome for a PEGylation project. To draw general guidelines for conducting PEGylation studies is not always easy or even possible because such experiments often require case-by-case optimization. On the other hand, several common methods can be used as starting examples for the development of tailor-made coupling conditions. Therefore, this chapter aims to provide a basic introduction to a wide range of PEGylation procedures for those researchers who may not be familiar with this field.
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Mero A, Schiavon M, Veronese FM, Pasut G. A new method to increase selectivity of transglutaminase mediated PEGylation of salmon calcitonin and human growth hormone. J Control Release 2011; 154:27-34. [DOI: 10.1016/j.jconrel.2011.04.024] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 04/13/2011] [Accepted: 04/22/2011] [Indexed: 10/18/2022]
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Chih HW, Gikanga B, Yang Y, Zhang B. Identification of Amino Acid Residues Responsible for the Release of Free Drug from an Antibody–Drug Conjugate Utilizing Lysine–Succinimidyl Ester Chemistry. J Pharm Sci 2011; 100:2518-25. [DOI: 10.1002/jps.22485] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Revised: 09/14/2010] [Accepted: 12/19/2010] [Indexed: 11/10/2022]
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Fee CJ, Van Alstine JM. Purification of PEGylated Proteins. METHODS OF BIOCHEMICAL ANALYSIS 2011; 54:339-62. [DOI: 10.1002/9780470939932.ch14] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Newa M, Bhandari KH, Tang L, Kalvapalle R, Suresh M, Doschak MR. Antibody-mediated "universal" osteoclast targeting platform using calcitonin as a model drug. Pharm Res 2011; 28:1131-43. [PMID: 21301934 PMCID: PMC3073043 DOI: 10.1007/s11095-011-0376-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Accepted: 01/19/2011] [Indexed: 11/30/2022]
Abstract
Purpose To generate and characterize a specific monoclonal antibody (mAb) against recombinant human RANK receptor and to develop an antiresorptive strategy using this mAb as an osteoclast-targeting platform that selectively targets osteoclast cells whilst delivering an attached (i.e. chemically conjugated) active drug cargo. Methods Using hybridoma technology, we generated a specific monoclonal antibody (mAb) against recombinant human RANK receptor and characterized by SDS PAGE, ELISA, Western Blot and immunocytochemistry, then synthesized osteoclast-targeting bioconjugates of salmon calcitonin (sCT) using this antibody by generating thiol groups on mAb using 2-Iminothiolane and subsequently reacting them with sCT-PEG-MAL synthesised from sCT and NHS-PEG-MAL. To test the efficacy of the conjugate in vitro, osteoclasts were generated from precursor RAW 264.7 cells by dosing with the cytokines macrophage-colony-stimulating factor (M-CSF), and RANK Ligand (RANKL) and TRAP activity assay, Resorption Pit Assay, TRAP staining were performed. Cytotoxicity of the mAb-sCT conjugate was also evaluated in RAW 264.7 cells; sCT bioactivity and CTR binding potential were evaluated by in vitro intracellular cAMP stimulation assay in human T47D breast cancer cells. Results Generation of antibody against human RANK receptor was confirmed by SDS PAGE, ELISA and Western Blot. Immunocytochemistry confirmed the osteoclast targeting potential of the antibody. Successful conjugation of the antibody with sCT was confirmed by SDS PAGE and ELISA.Multinucleated osteoclast formation was confirmed by staining for tartrate-resistant acid phosphatase (TRAP). Conjugate functionality was confirmed by TRAP activity and Resorption Pit assay, showing the inhibitory effect on osteoclast differentiation. cAMP assay confirmed the retention of calcitonin bioactivity after conjugation. Conclusions Our strategy offers the potential for a “universal” osteoclast-targeting platform—one that targets the RANK receptor on osteoclast cells by simply altering the conjugated cargo in order to affect the specific regulation of osteoclast cells.
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Affiliation(s)
- Madhuri Newa
- Faculty of Pharmacy & Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta T6G2N8, Canada
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Ruanjaikaen K, Zydney AL. Purification of singly PEGylated α-lactalbumin using charged ultrafiltration membranes. Biotechnol Bioeng 2010; 108:822-9. [PMID: 21404256 DOI: 10.1002/bit.22991] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Revised: 10/09/2010] [Accepted: 10/15/2010] [Indexed: 11/12/2022]
Abstract
One of the challenges in producing a PEGylated therapeutic protein is that the PEGylation reaction typically generates a mixture of both singly and multiply PEGylated species. The objective of this study was to examine the feasibility of using ultrafiltration for the purification of a singly PEGylated protein from the multiply PEGylated conjugates. Data were obtained with α-lactalbumin that was PEGylated with a 20 kDa activated PEG, with the ultrafiltration performed over a range of pH and ionic strength using both unmodified and negatively charged composite regenerated cellulose membranes. Purification of the singly PEGylated α-lactalbumin from the multiply PEGylated species was accomplished using a diafiltration process with a negatively charged membrane at pH 5 and an ionic strength of 0.4 mM, conditions that maximized the electrostatic exclusion of the multiply PEGylated species from the charged membrane. The diafiltration process provided more than 97% yield with greater than 20-fold purification between the singly and doubly PEGylated proteins and nearly complete removal of the more heavily PEGylated species. The singly PEGylated α-lactalbumin was recovered as a dilute filtrate solution, although this dilution could be eliminated using a cascade filtration or the final product could be re-concentrated in a second ultrafiltration as part of the final formulation. These results demonstrate the feasibility of using ultrafiltration for the purification of singly PEGylated protein therapeutics.
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Affiliation(s)
- Krisada Ruanjaikaen
- Department of Chemical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
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PK/PD modelling of comb-shaped PEGylated salmon calcitonin conjugates of differing molecular weights. J Control Release 2010; 149:126-32. [PMID: 20946924 DOI: 10.1016/j.jconrel.2010.10.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 09/29/2010] [Accepted: 10/03/2010] [Indexed: 11/23/2022]
Abstract
Salmon calcitonin (sCT) was conjugated via cysteine-1 to novel comb-shaped end-functionalised (poly(PEG) methyl ether methacrylate) (sCT-P) polymers, to yield conjugates of total molecular weights (MW) inclusive of sCT: 6.5, 9.5, 23 and 40kDa. The conjugates were characterised by HPLC and their in vitro and in vivo bioactivity was measured by cAMP assay on human T47D cells and following intravenous (i.v.) injection to rats, respectively. Stability against endopeptidases, rat serum and liver homogenates was assessed. There were linear and exponential relationships between conjugate MW with potency and efficacy respectively, however the largest MW conjugate still retained 70% of E(max) and an EC(50) of 3.7nM. In vivo, while free sCT and the conjugates reduced serum [calcium] to a maximum of 15-30% over 240 min, the half-life (T(1/2)) was increased and the area under the curve (AUC) was extended in proportion to conjugate MW. Likewise, the polymer conferred protection on sCT against attack by trypsin, chymotrypsin, elastase, rat serum and liver homogenates, with the best protection afforded by sCT-P (40kDa). Mathematical modelling accurately predicted the MW relationships to in vitro efficacy, potency, in vivo PK and enzymatic stability. With a significant increase in T(1/2) for sCT, the 40kDa MW comb-shaped PEG conjugate of sCT may have potential as a long-acting injectable formulation.
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21
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Fractionation of different PEGylated forms of a protein by chromatography using environment-responsive membranes. J Chromatogr A 2010; 1217:5595-601. [DOI: 10.1016/j.chroma.2010.06.061] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Revised: 06/21/2010] [Accepted: 06/23/2010] [Indexed: 11/20/2022]
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22
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Lu X, Gough PC, DeFelippis MR, Huang L. Elucidation of PEGylation site with a combined approach of in-source fragmentation and CID MS/MS. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:810-818. [PMID: 20189826 DOI: 10.1016/j.jasms.2010.01.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2009] [Revised: 01/11/2010] [Accepted: 01/11/2010] [Indexed: 05/28/2023]
Abstract
Poly(ethylene glycol) (PEG)ylation of peptides and proteins creates significant challenges for detailed structural characterization, such as PEG heterogeneity, site of addition and number of attached PEGylated moieties. Recently, we published a novel LC/MS methodology with a post-column addition of amines to obtain accurate masses of PEGylated peptides and proteins. The accurate masses can be used to assign the structures and number of attached PEGs [15], but the PEGylation site remains unclear in situations where multiple potential attachments are involved. Here, we present a methodology combining in-source fragmentation (ISF) with CID-MS/MS to elucidate the PEGylated sites in PEGylated products. All PEGylated samples, either prepared in acidic solution, or collected from a RP-HPLC stream, were first ionized via ISF to produce products containing small PEG fragment attachment, and then those fragment ions obtained were sequenced via CID MS/MS to deduce the PEGylation site. The methodology was successfully applied to PEGylated glucagon and IgG4 antibody light chain, which demonstrated that the small PEG fragments attached were stable during the CID activation.
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Affiliation(s)
- Xiaojun Lu
- Bioproduct Research and Development, Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USA
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23
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Wang X, Tian Y, Lin H, Zang L. Preparation and characterization of PEGylated terlipressin. J Appl Polym Sci 2010. [DOI: 10.1002/app.31876] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Jones MW, Mantovani G, Ryan SM, Wang X, Brayden DJ, Haddleton DM. Phosphine-mediated one-pot thiol-ene "click" approach to polymer-protein conjugates. Chem Commun (Camb) 2009:5272-4. [PMID: 19707643 DOI: 10.1039/b906865a] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We employ water-soluble organic phosphines as key reagents in a one-pot synthetic protocol where a (poly)peptide disulfide bridge is first reduced followed by subsequent reaction of the two thiols in situ with poly(monomethoxy ethylene glycol)(meth)acrylates (p(mPEG)(M)A); we use salmon calcitonin (sCT) as a disulfide bridge-containing peptide, which contains a disulfide bridge-Cys1-Cys7-that can be reduced to give two sulfhydryl units available for thiol functionalisation; bioactivity is retained.
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Affiliation(s)
- Mathew W Jones
- Department of Chemistry, University of Warwick, Coventry, UKCV4 7AL
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Cheng W, Lim LY. Synthesis, Characterization and In Vivo Activity of Salmon Calcitonin Coconjugated With Lipid and Polyethylene Glycol. J Pharm Sci 2009; 98:1438-51. [DOI: 10.1002/jps.21524] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Chae SY, Chun YG, Lee S, Jin CH, Lee ES, Lee KC, Youn YS. Pharmacokinetic and pharmacodynamic evaluation of site-specific PEGylated glucagon-like peptide-1 analogs as flexible postprandial-glucose controllers. J Pharm Sci 2009; 98:1556-67. [DOI: 10.1002/jps.21532] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Ryan SM, Wang X, Mantovani G, Sayers CT, Haddleton DM, Brayden DJ. Conjugation of salmon calcitonin to a combed-shaped end functionalized poly(poly(ethylene glycol) methyl ether methacrylate) yields a bioactive stable conjugate. J Control Release 2009; 135:51-9. [PMID: 19168100 DOI: 10.1016/j.jconrel.2008.12.014] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2008] [Revised: 12/11/2008] [Accepted: 12/17/2008] [Indexed: 11/19/2022]
Abstract
Salmon calcitonin (sCT) was conjugated via its N-terminal cysteine to a comb-shaped end-functionalized poly(poly(ethylene glycol) methyl ether methacrylate) (PolyPEG, 6.5 kDa), and to linear PEG (5 kDa). Conjugate molecular weight and purity was assessed by SEC-HPLC and MALDI-TOF MS. Bioactivity of conjugates was measured by cyclic AMP assay in T47D cells. Calcium and calcitonin levels were measured in rats following intravenous injections. Stability of conjugates was tested against serine proteases, intestinal and liver homogenates and serum. Cytotoxicity of conjugates was assessed by lactate dehydrogenase (LDH) assay and by haemolytic assay of rat red blood cells. Results showed that the two conjugates were of high purity with molecular weights similar to predictions. Both conjugates retained more than 85% bioactivity in vitro and had nanomolar EC(50) values similar to sCT. While both sCT-PolyPEG(6.5 K) and sCT-PEG(5 K) were resistant to metabolism by serine proteases, homogenates and serum, PolyPEG (6.5 K) was more so. Although both conjugates reduced serum calcium to levels similar to those achieved with sCT, PolyPEG(6.5 K) extended the T(1/2) and AUC of serum sCT over values achieved with sCT-PEG and sCT itself. None of PolyPEG, PEG or methacrylic acid displayed significant cytotoxicity. PolyPEG may therefore have potential to improve pharmacokinetic profiles of injected peptides.
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Affiliation(s)
- Sinéad M Ryan
- UCD School of Agriculture, Food Science and Veterinary Medicine and UCD Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
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Huang L, Gough PC, DeFelippis MR. Characterization of Poly(ethylene glycol) and PEGylated Products by LC/MS with Postcolumn Addition of Amines. Anal Chem 2008; 81:567-77. [DOI: 10.1021/ac801711u] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lihua Huang
- Bioproduct Research & Development, Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285
| | - P. Clayton Gough
- Bioproduct Research & Development, Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285
| | - Michael R. DeFelippis
- Bioproduct Research & Development, Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285
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Hee Na D, Seok Youn Y, Bok Lee I, Ji Park E, Jeon Park C, Choon Lee K. Effect of Molecular Size of PEGylated Recombinant Human Epidermal Growth Factor on the Biological Activity and Stability in Rat Wound Tissue. Pharm Dev Technol 2008; 11:513-9. [PMID: 17101522 DOI: 10.1080/10837450600941053] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The purpose of this study was to investigate the effect of size of polyethylene glycol (PEG) conjugated to recombinant human epidermal growth factor (rhEGF) on its stability in skin wound tissue and in vitro biological activity to find the desirable conjugate as topical therapeutic agent for wound healing. Site-specific PEGylation at N-terminus of rhEGF was performed with monomethoxy PEG-Butyraldehyde derivatives (MW 2, 5, and 20 kDa). Mono-PEG-rhEGFs retained 60-70% of biological activity of native rhEGF, and the effect of PEG size was not significant. The improvement of stability in the rat skin wound tissue was dependent on the increase of the PEG size attached. The degradation half-lives of native rhEGF, mono-PEG-2K-, -5K-, and -20K-rhEGFs were 1.1, 3.1, 5.2, and 41.5 hr, respectively. Therefore, mono-PEG-20K-rhEGF was considered to be the most desirable in terms of the increase of stability and the preservation of biological activity. This study suggests that the high molecular weight PEG at N-terminus of rhEGF would give a satisfactory stabilizing effect and thus may improve therapeutic efficacy in clinical use.
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Affiliation(s)
- Dong Hee Na
- College of Pharmacy, Kyungsung University, Nam-Ku, Busan, Korea
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Mansoor S, Youn YS, Lee KC. Oral Delivery of Mono-PEGylated sCT (Lys18) in Rats: Regional Difference in Stability and Hypocalcemic Effect. Pharm Dev Technol 2008; 10:389-96. [PMID: 16176019 DOI: 10.1081/pdt-65686] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In the in vitro experiment using a luminal, mucosal, and fecal fluid/extract from jejunum and colon of a rat, Lys18-residue modified mono-PEG(2k)-sCT (Lys18-PEG(2K)-sCT) exhibited a longer half-life than salmon calcitonin (sCT) in a colonic fluid and its extract. A physical adsorption study showed that Lys18-PEG(2K)-sCT had lower adsorption in the feces than sCT over an 8-hr period. An absorption study of the sCT and Lys18-PEG(2K)-sCT from the jejunum and colon using an in situ closed-loop technique in anesthetized rats showed a dose-dependent reduction in the plasma Ca2+ level but to a certain limit. Furthermore, the hypocalcemic response by intracolonic administration was significantly higher than the intrajejunal one, demonstrating that the colon had better absorption. In particular, Lys18-PEG(2K)-sCT (5 microg/rats) produced the most pronounced hypocalcemia after the intracolonic administration, which resulted in a sustained reduction in the serum calcium level over an 8-hr period, with a maximum reduction (% max(d)) of 38% after 4 hr. The overall reduction in the serum calcium levels, which was expressed as the net change in the AUC relative to the control over an 8-hr period, was 25.51 +/- 3.38 for Lys18-PEG(2K)-sCT. The relative pharmacological bioavailability of the intracolonically administered Lys18-PEG(2K)-sCT was 2.1-fold higher than sCT and the absolute pharmacological bioavailability was 73.59% of i.v.-injected sCT in an 8-hr period. Overall, this study highlights the feasibility of the oral delivery of Lys18-PEG(2K)-sCT in achieving a sustained calcium-lowering effect.
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Affiliation(s)
- Saffar Mansoor
- Drug Targeting Laboratory, College of Pharmacy, SungKyunKwan University, Suwon City, Korea
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Improved intrapulmonary delivery of site-specific PEGylated salmon calcitonin: optimization by PEG size selection. J Control Release 2007; 125:68-75. [PMID: 18023905 DOI: 10.1016/j.jconrel.2007.10.008] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2007] [Revised: 10/10/2007] [Accepted: 10/14/2007] [Indexed: 11/21/2022]
Abstract
The purpose of this study was to demonstrate the biological potentials of PEGylated salmon calcitonin (PEG-sCT) derivatives administered intratracheally and their dependences on PEG Mw (1, 2, 5 kDa). Initially, three different PEG-sCT derivatives were site-specifically synthesized by attaching PEG to the Lys(18)-amine. In an attempt to examine the pulmonary feasibilities of these derivatives, the following evaluations were undertaken to determine their; (i) proteolytic resistances to pulmonary enzymes, (ii) bioactivities, and (iii) pulmonary pharmacokinetic and pharmacologic profiles. The results obtained showed that the pulmonary stabilities and pharmacokinetic properties of these derivatives were greatly improved by increasing PEG Mw. PEG-sCTs had 10.5-, 40.1-, and 1066.0-fold greater stabilities than that of sCT in rat lung homogenates. Moreover, all pharmacokinetic parameters (AUC(inf), C(max), t(1/2), and others) of these derivatives in endotracheally cannulated rats were significantly improved by PEGylation. Specifically, C(max) values increased on increasing PEG Mw, i.e., 78.1+/-21.1, 102.9+/-9.1, and 115.2+/-5.7 for 1, 2, 5 kDa, respectively, vs. 54.8+/-3.9 ng/mL for sCT. Their circulating t(1/2) values also increased to 53.9+/-6.0, 100.7+/-21.7, and 119.4+/-13.7 min, respectively, vs. 34.6+/-7.6 min for sCT. Despite having the best properties, Lys(18)-PEG(5k)-sCT was found to have significantly lower hypocalcemic efficacy than other PEG-sCTs, probably due to its reduced intrinsic bioactivity ( approximately 30% vs. sCT). Rather, Lys(18)-PEG(2k)-sCT showed the most promising pulmonary potential because of its well-preserved bioactivity (>80% of sCT). Taken together, our findings suggest that the site-specific substitution to peptides like sCT with a PEG of an appropriate size offers optimized therapeutic potential by dual advantages, i.e., (i) increased proteolytic stability and (ii) extended circulating half-life in terms of intrapulmonary delivery.
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Choi HK, Chun MK, Lee SH, Jang MH, Kim HD, Jung CS, Oh SY. In vitro and in vivo study of poly(ethylene glycol) conjugated ketoprofen to extend the duration of action. Int J Pharm 2007; 341:50-7. [PMID: 17517483 DOI: 10.1016/j.ijpharm.2007.03.045] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2006] [Revised: 02/15/2007] [Accepted: 03/29/2007] [Indexed: 11/22/2022]
Abstract
Ketoprofen-polyethylene glycol (PEG) conjugates (KPEG) were prepared and their potential as a prolonged release system was investigated. Three KPEG conjugates were synthesized from ketoprofen and methoxy PEG with three different molecular weights by esterification in the presence of DCC. The KPEG conjugates were characterized by FT-IR and (1)H NMR spectroscopy. The rate of hydrolysis profile showed a specific acid-base catalysis pattern with a minimum at pH 4-5. The pharmacokinetic study after the intravenous and intramuscular administration of KPEG750 showed that the plasma levels of KP increased slowly and reached a maximum concentration at later time. The AUC of KPEG750 was higher than that after administering an equivalent dose of ketoprofen except 40mg/kg dose of intramuscular administration. The tail-flick experiment and paw edema test after intramuscular administration showed that KPEG750 had extended analgesic and anti-inflammatory effects compared with ketoprofen. These results suggest that KPEG could be a promising NSAID prodrug with an extended pharmacological effect owing to delayed-release of parent drug.
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MESH Headings
- Animals
- Anti-Inflammatory Agents, Non-Steroidal/administration & dosage
- Anti-Inflammatory Agents, Non-Steroidal/blood
- Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis
- Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics
- Carrageenan
- Chemistry, Pharmaceutical
- Delayed-Action Preparations
- Dicyclohexylcarbodiimide/chemistry
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Drug Carriers
- Drug Compounding
- Hydrogen-Ion Concentration
- Hydrolysis
- Inflammation/chemically induced
- Inflammation/prevention & control
- Injections, Intramuscular
- Injections, Intravenous
- Ketoprofen/administration & dosage
- Ketoprofen/analogs & derivatives
- Ketoprofen/blood
- Ketoprofen/chemical synthesis
- Ketoprofen/pharmacokinetics
- Magnetic Resonance Spectroscopy
- Male
- Molecular Weight
- Pain Measurement
- Pain Threshold/drug effects
- Polyethylene Glycols/chemistry
- Prodrugs/administration & dosage
- Prodrugs/chemical synthesis
- Prodrugs/pharmacokinetics
- Rats
- Rats, Sprague-Dawley
- Solubility
- Spectroscopy, Fourier Transform Infrared
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Affiliation(s)
- Hoo-Kyun Choi
- BK21 Project Team, School of Pharmacy, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju 501-759, Republic of Korea
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NODAKE Y, SAKAKIBARA R, YAMASAKI N. Overview of the Lysozyme-Monomethoxypolyethylene Glycol Conjugate as a Model for Protein Tailoring. KOBUNSHI RONBUNSHU 2007. [DOI: 10.1295/koron.64.716] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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34
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Youn YS, Na DH, Lee KC. High-yield production of biologically active mono-PEGylated salmon calcitonin by site-specific PEGylation. J Control Release 2006; 117:371-9. [PMID: 17207880 DOI: 10.1016/j.jconrel.2006.11.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2006] [Revised: 10/24/2006] [Accepted: 11/14/2006] [Indexed: 11/27/2022]
Abstract
The purpose of this study was to develop and optimize a unique one-pot, two-step site-specific PEGylation method suitable for the high-yield production of mono-PEGylated (Lys(18)) salmon calcitonin (Lys(18)-PEG-sCT), which was previously demonstrated to have superior pharmaceutical properties to other conjugates. For the site-specific PEGylation, this study used the sCT derivative (FMOC(1,11)-sCT), which was FMOC protected at Cys(1)- and Lys(11)-amines among three PEGylation sites including Lys(18)-amine. This PEGylation process was achieved by the consecutive one-pot, two-step reaction: (i) the PEG conjugation to FMOC(1,11)-sCT; and (ii) the subsequent deprotection of FMOC group from the PEGylated FMOC(1,11)-sCT. The optimized reaction resulted in the high production yield of Lys(18)-PEG-sCT (about 86%), compared with that from conventional non-specific PEGylation (about 18%). The prepared Lys(18)-PEG-sCT conjugate showed improved biological stability without the loss in the in vitro and in vivo biological activity by PEGylation. Consequently, this site-specific PEGylation using an FMOC protection/deprotection strategy showed great usefulness in the production of the most promising Lys(18)-PEG-sCT conjugate with a high yield.
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Affiliation(s)
- Yu Seok Youn
- Drug Targeting Laboratory, College of Pharmacy, SungKyunKwan University, 300 Chonchon-dong, Jangan-ku, Suwon City 440-746, Korea
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35
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Youn YS, Chae SY, Lee S, Jeon JE, Shin HG, Lee KC. Evaluation of therapeutic potentials of site-specific PEGylated glucagon-like peptide-1 isomers as a type 2 anti-diabetic treatment: Insulinotropic activity, glucose-stabilizing capability, and proteolytic stability. Biochem Pharmacol 2006; 73:84-93. [PMID: 17054919 DOI: 10.1016/j.bcp.2006.09.013] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Revised: 09/06/2006] [Accepted: 09/08/2006] [Indexed: 11/26/2022]
Abstract
PEGylation has been considered to be a good biotechnique for improving the therapeutic value of glucagon-like peptide-1 (GLP-1) analogs for the treatment of type 2 diabetes. Despite the attractive anti-diabetic potentials, GLP-1 does not exert its full biological action because of its extremely short life-time in vivo due to rapid proteolytic degradation. Here, the enzyme-resistant mono-PEGylated GLP-1 isomers substituted at Lys(26)- or Lys(34)-amine were prepared through a newly devised site-specific PEGylation process using a maleic anhydride-protection/deprotection method. The therapeutic potentials of these site-specific PEGylated GLP-1 isomers (Lys(26)- or Lys(34)-PEG-GLP-1) along with His(7)-(N-terminus) PEG-GLP-1 were evaluated by examining their insulinotropic activity, glucose-stabilizing capability, and proteolytic stability. Lys(34)-PEG-GLP-1 was found to have the well-preserved insulinotropic activity (93% efficacy versus GLP-1) in isolated rat pancreatic islets. Furthermore, Lys(34)-PEG-GLP-1 showed the most prominent glucose-stabilizing capability, evaluated via an oral glucose tolerance test in db/db mice by considering the following three crucial factors: (i) maximum blood glucose level (BGL), (ii) required time to lower the BGL below 100mg/dl, and (iii) total hypoglycemic degree. Additionally, Lys(34)-PEG-GLP-1 had longer half-lives than the other PEGylated GLP-1s in the dipeptidyl peptidase IV (DPP IV) inhibitor-treated liver or kidney homogenate, and its stability against DPP IV was also comparable to that of Lys(26)-PEG-GLP-1. Taken together, Lys(34)-PEG-GLP-1 displayed the promising characteristics in all evaluations versus His(7)- or Lys(26)-PEG-GLP-1. This site-specific PEGylated GLP-1 analog would have therapeutic usefulness for treating type 2 diabetes on account of the well-preserved insulinotropic activity, the increased proteolytic stability, and thereby the improved glucose-stabilizing capability.
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Affiliation(s)
- Yu Seok Youn
- Drug Targeting Laboratory, College of Pharmacy, SungKyunKwan University, 300 Chonchon-dong, Jangan-ku, Suwon City 440-746, Republic of Korea
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Youn YS, Jung JY, Oh SH, Yoo SD, Lee KC. Improved intestinal delivery of salmon calcitonin by Lys18-amine specific PEGylation: stability, permeability, pharmacokinetic behavior and in vivo hypocalcemic efficacy. J Control Release 2006; 114:334-42. [PMID: 16884808 DOI: 10.1016/j.jconrel.2006.06.007] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2006] [Revised: 06/07/2006] [Accepted: 06/09/2006] [Indexed: 11/23/2022]
Abstract
Peptides like salmon calcitonin (sCT) are subjected to aggressive proteolytic attack by various intestinal enzymes, and fractions that enter the systemic circulation via the intestinal route are rapidly inactivated by tissue accumulation and glomerular filtration. Here, we describe the beneficial effects of the Lys(18)-amine specific PEGylation of sCT on the intestinal delivery of sCT. Two key properties were enhanced by the PEGylation process: (i) the resistance of sCT to intestinal enzymes and (ii) the systemic clearance of sCT that had entered the circulation. Initially, we evaluated the cAMP-secreting activities of PEG(2K)-sCT isomers substituted at Cys(1)-, Lys(11)- or Lys(18)-amine position in T47D cells, and found that sCT PEGylated at Lys(18)-amine (Lys(18)-PEG(2K)-sCT) had the highest bioactivity. We then investigated the stability of Lys(18)-PEG(2K)-sCT in the presence of intestinal enzymes, its abilities to traverse the intestinal membrane, its pharmacokinetic behavior and in vivo hypocalcemic efficacy. Results show that Lys(18)-PEG(2K)-sCT has significantly increased resistance to pancreatic peptidases and brush-border peptidases. Despite the molecular size increase caused by PEGylation, Lys(18)-PEG(2K)-sCT was found to have an intestinal permeability similar to that of unmodified sCT (p>0.59) over an apical concentration range 12.5-100 microM in a Caco-2 cell monolayer transport system. In particular, tissue distribution results showed that (125)I-labeled Lys(18)-PEG(2K)-sCT markedly resists liver accumulation and glomerular filtration; levels were reduced by 75% and 50% vs. sCT. Finally, the hypocalcemic efficacy of intestinally administered Lys(18)-PEG(2K)-sCT, measured as total serum calcium in a rat model, was 5.8 and 3.0 times that of sCT at 100 and 200 IU/kg (p<0.025). Our findings suggest that this site-specific conjugation of peptides with PEG of proper size enhances pharmacokinetic properties by increasing their abilities to resist both proteolysis and systemic clearance without significantly reducing their membrane permeabilities or bioactivities. We believe that this concept, namely, dual effects by PEGylation, has great potential value because it presents a practical means of enhancing the efficacies of the peroral/intestinal pharmacologic route.
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Affiliation(s)
- Yu Seok Youn
- Drug Targeting Laboratory, College of Pharmacy, SungKyunKwan University, 300, Chonchon-dong, Jangan-ku, Suwon City 440-746, South Korea
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38
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Gámez A, Sarkissian CN, Wang L, Kim W, Straub M, Patch MG, Chen L, Striepeke S, Fitzpatrick P, Lemontt JF, O'Neill C, Scriver CR, Stevens RC. Development of pegylated forms of recombinant Rhodosporidium toruloides phenylalanine ammonia-lyase for the treatment of classical phenylketonuria. Mol Ther 2005; 11:986-9. [PMID: 15922970 DOI: 10.1016/j.ymthe.2005.02.013] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2005] [Revised: 02/04/2005] [Accepted: 02/05/2005] [Indexed: 11/28/2022] Open
Abstract
Phenylketonuria (PKU) is a metabolic disorder due primarily to mutations in the PAH gene that impair both phenylalanine hydroxylase activity and disposal of l-phenylalanine from the normal diet. Excess phenylalanine is toxic to cognitive development and a low-phenylalanine diet prevents mental retardation, but it is a difficult therapeutic option. Previous studies with recombinant phenylalanine ammonia-lyase, PAL, demonstrated pharmacologic and physiologic proofs of principle for PAL as an alternative therapy for PKU but its immunogenicity was problematic. From a series of formulations of linear and branched polyethylene glycols chemically conjugated to PAL, we have created a parenteral therapeutic agent for PKU treatment. All the pegylated molecules were fully characterized in vitro and the most promising formulations were then tested in vivo in the PKU mouse model. The linear 20-kDa PEG-PAL combination abolished in vivo immunogenicity after repeated challenge while retaining full catabolic activity against phenylalanine, suggesting potential as a novel PKU therapeutic.
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Affiliation(s)
- Alejandra Gámez
- Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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Youn YS, Na DH, Yoo SD, Song SC, Lee KC. Carbohydrate-specifically polyethylene glycol-modified ricin A-chain with improved therapeutic potential. Int J Biochem Cell Biol 2005; 37:1525-33. [PMID: 15833282 DOI: 10.1016/j.biocel.2005.01.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2004] [Revised: 01/03/2005] [Accepted: 01/13/2005] [Indexed: 10/25/2022]
Abstract
Ricin A-chain, which exhibits excellent cytotoxicity to tumor cells, has been widely used as an immunotoxin source. However, it has the fatal shortcoming of poor pharmacokinetics due to the tremendous liver uptake via carbohydrate-mediated recognition. Modification of proteins with polyethylene glycol, PEGylation, has the advantages of shielding the specific sites and prolonging the biological half-life. In this study, the carbohydrate-specific PEGylation of ricin A-chain was considered to be a novel approach to overcome this limitation. The carbohydrate group of ricin A-chain was oxidized by sodium m-periodate and further specifically conjugated with hydrazide-derivatized PEG. For a comparative study, the PEGylated ricin A-chain at amino groups was prepared using the hydroxysuccinimide ester-derivatized PEG. The carbohydrate-specifically PEGylated ricin A-chain showed a markedly lower liver uptake and systemic clearance compared with the amine-directly PEGylated ricin A-chain as well as the unmodified ricin A-chain. Furthermore, carbohydrate-specifically PEGylated ricin A-chain showed a significantly higher in vitro ribosome-inactivating activity than the amine-directly PEGylated ricin A-chain. These findings clearly demonstrate that the carbohydrate-specificity as well as PEGylation plays an important role in improving the in vivo pharmacokinetic properties and in vitro bioactivity. Therefore, these results suggest that the therapeutic use of immunotoxins constructed using this carbohydrate-specifically PEGylated ricin A-chain has potential as a cancer therapy.
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Affiliation(s)
- Yu Seok Youn
- Drug Targeting Laboratory, College of Pharmacy, SungKyunKwan University, 300 Chonchon-dong, Jangan-ku, Suwon City 440-746, South Korea
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Shin BS, Jung JH, Lee KC, Yoo SD. Nasal absorption and pharmacokinetic disposition of salmon calcitonin modified with low molecular weight polyethylene glycol. Chem Pharm Bull (Tokyo) 2005; 52:957-60. [PMID: 15304989 DOI: 10.1248/cpb.52.957] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study was performed to examine the absorption potential of polyethylene glycol (PEG)-modified salmon calcitonin (sCT) in rats administered via the nasal route. Previous studies have used relatively high molecular weight polyethylene glycols (e.g., > or =5000 daltons) for PEG-modification of sCT to provide increased metabolic stability and biological half-life. Unlike these studies, the present study utilized a low molecular weight succinimidyl-propionated monomethoxy-poly(ethylene glycol) (MW 2000). It was hypothesized that the potential for membrane transport would not be significantly altered due to a relatively small increase in the molecular size while the metabolic stability would be enhanced due to resistance to proteolytic degradation. After PEG-modification of sCT, the mono-PEG positional isomer (mono-PEG2k-sCT) was separated from di-PEG2k-sCT, tri-PEG2k-sCT, and unmodified sCT by size exclusion chromatography. The mono-PEG2k-sCT and unmodified sCT were radioiodinated, and the resulting 125I-sCT and 125I-mono-PEG2k-sCT were separated from free iodine by RP HPLC and confirmed by MALDI-TOF MS. The 125I-sCT and 125I-mono-PEG2k-sCT were administered to rats via the nasal route, and serial blood, tissue, and urine samples were taken for up to 36 h for the determination of radioactivity. Mono-PEG2k-sCT exhibited significantly increased AUC (20,638 vs. 3,650 ng.min/ml), tmax (520 vs. 77 min), and t1/2,lambdaz (923 vs. 199 min) compared with unmodified sCT. This study demonstrates that mono-PEG2k-sCT is absorbed systemically when given by the intranasal route, exhibiting altered absorption kinetics compared with unmodified sCT.
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Youn YS, Na DH, Yoo SD, Song SC, Lee KC. Chromatographic separation and mass spectrometric identification of positional isomers of polyethylene glycol-modified growth hormone-releasing factor (1-29). J Chromatogr A 2004; 1061:45-9. [PMID: 15633743 DOI: 10.1016/j.chroma.2004.10.062] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A one-step chromatographic method capable of separating all isomers of polyethylene glycol (PEG)-growth hormone-releasing factor (GRF) (1-29) conjugates was developed. The unmodified GRF (1-29) and seven different isomers of PEG-GRF (1-29) conjugates were separated by using a simple reversed-phase HPLC method depending on the differences of hydrophobicity due to the number and site of PEG attachment. The PEGylation sites of all isomers of PEG-GRF (1-29) conjugates were identified by determining the molecular masses of the Lys-C digested fragments with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. This study is a first report for the separation of all PEG-conjugate isomers and would be useful for further studies to find the promising conjugate by evaluating biological activity and stability of each isomer.
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Affiliation(s)
- Yu Seok Youn
- Drug Targeting Laboratory, College of Pharmacy, SungKyunKwan University, 300 Chonchon-dong, Jangan-ku, Suwon City 440-746, South Korea
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Affiliation(s)
- Samantha Lien
- Dept of Protein Engineering, Genentech, 1 DNA Way, South San Francisco, CA 94080, USA
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Gámez A, Wang L, Straub M, Patch MG, Stevens RC. Toward PKU Enzyme Replacement Therapy: PEGylation with Activity Retention for Three Forms of Recombinant Phenylalanine Hydroxylase. Mol Ther 2004; 9:124-9. [PMID: 14741785 DOI: 10.1016/j.ymthe.2003.11.002] [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: 10/26/2022] Open
Abstract
Phenylketonuria (PKU) is a disease in which phenylalanine and phenylalanine-derived metabolites build up to neurotoxic levels due to mutations in the phenylalanine hydroxylase gene (PAH). Enzyme replacement therapy is a viable option to supply active PAH. However, the inherent protease sensitivity and potential immunogenicity of PAH have precluded adoption of this approach. In this report, we have used polyethylene glycol derivatization (PEGylation) to produce protected forms of PAH for potential therapeutic use. Three recombinantly produced PAH enzymes were reacted with activated PEG species, with the aim of developing a stable and active PKU enzyme replacement. Tetrameric full-length human PAH, dimeric double-truncated (DeltaN102-DeltaC428) human PAH, and monomeric Chromobacterium violaceum PAH were PEGylated with succinimidyl succinate polyethylene glycol of molecular weight 5000 or 20,000 Da. Characterization of the PEGylated species was accomplished with MALDI-TOF mass spectrometry, SDS-PAGE, and specific activity measurements using ESI mass spectrometry. All PEG-derivatized PAH species retained catalytic activity, and, at low numbers of PEG molecules attached, these PEGylated PAH proteins were found to be more active and more stable than their non-derivatized PAH counterparts.
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Affiliation(s)
- Alejandra Gámez
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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Na DH, Murty SB, Lee KC, Thanoo BC, DeLuca PP. Preparation and stability of poly(ethylene glycol) (PEG)ylated octreotide for application to microsphere delivery. AAPS PharmSciTech 2003; 4:E72. [PMID: 15198567 PMCID: PMC2750665 DOI: 10.1208/pt040472] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The purpose of this study was to prepare poly(ethylene glycol) (PEG)ylated octreotide and investigate the stability against acylation by polyester polymers such as poly(lactic acid) and poly(lactic-co-glycolic acid). Octreotide was modified by reaction with monomethoxy PEG-propionaldehyde (molecular weight 5,000) in the presence of sodium cyanoborohydride. The mono-PEGylated fraction was isolated by reversed-phase high-performance liquid chromatography (HPLC) and characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Circular dichroism demonstrated no significant secondary structural differences between mono-PEGylated octreotide (mono-PEG-octreotide) and intact octreotide. As a test system for the stability study against acylation reaction, lactic acid (LA) solutions with various concentrations and pH values were prepared with water dilution and subsequent accelerated equilibration at 90 degrees C for 24 hours. Native octreotide was found to be acylated in all the diluted LA solutions with different concentrations (42.5%, 21.3%, and 8.5%, wt/wt) and pH values (2.25, 1.47, and 1.85, respectively). The remaining amounts of intact octreotide continuously decreased to 50% through 30 days of incubation at 37 degrees C. MALDI-TOF MS identified the octreotide to be acylated by LA units. However, acylation reaction of mono-PEG-octreotide in LA solutions was negligible, and the remaining amounts of intact one through 30 days of incubation in LA solutions were also comparable to the initial concentration. These data suggest that mono-PEG-octreotide may prevent the acylation reaction in degrading PLA microspheres and possibly serve as a new source for somatostatin microsphere formulation.
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Affiliation(s)
- Dong Hee Na
- />Faculty of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, 40536 Lexington, KY
| | - Santos B. Murty
- />Faculty of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, 40536 Lexington, KY
| | - Kang Choon Lee
- />Drug Targeting Laboratory, College of Pharmacy, SungKyunKwan University, 440-746 Suwon, Korea
| | | | - Patrick P. DeLuca
- />Faculty of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, 40536 Lexington, KY
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Wang Y, Dou H, Cao C, Zhang N, Ma J, Mao J, Wu H. Solution structure and biological activity of recombinant salmon calcitonin S-sulfonated analog. Biochem Biophys Res Commun 2003; 306:582-9. [PMID: 12804605 DOI: 10.1016/s0006-291x(03)01028-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Salmon calcitonin S-sulfonated analog (abbreviated as [S-SO(3)(-)]rsCT) was prepared by introducing two sulfonic groups into the side chains of Cys1 and Cys7 of recombinant salmon calcitonin. The hypocalcemic potency of this open-chain analog is 5500IU/mg, which is about 30% higher than that (4500IU/mg) of the wild type. The solution conformation of [S-SO(3)(-)]rsCT was studied in aqueous trifluoroethanol solution by CD, 2D-NMR spectroscopy, and distance geometry calculations. In the mixture of 60% TFE and 40% water, the peptide assumes an amphipathic alpha-helix in the region of residues 4-22, which is one turn longer than that of the native sCT. The structural feature analysis of the peptide revealed the presence of hydrophobic surface composed of five hydrophobic side chains of residues Leu4, Leu9, Leu12, Leu16, and Leu19, and a network of salt-bridges that consisted of a tetrad of oppositely charged side chains (Cys7-SO(3)(-)-Lys11(+)-Glu15(-)-Lys18(+)). The multiple salt bridges resulted in the stabilization of the longer amphipathic alpha-helix. Meanwhile, the higher hypocalcemic potency of the peptide could be attributed to the array of hydrophobic side chains of five leucine residues of the amphipathic alpha-helix.
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Affiliation(s)
- Yuefeng Wang
- State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, 200032, Shanghai, PR China
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46
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Lee H, Jang IH, Ryu SH, Park TG. N-terminal site-specific mono-PEGylation of epidermal growth factor. Pharm Res 2003; 20:818-25. [PMID: 12751640 DOI: 10.1023/a:1023402123119] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE N-terminal site-specific mono-PEGylation of recombinant human epidermal growth factor (EGF) was accomplished using polyethyleneglycol (PEG) derivatives (Mw = 2000 and 5000) through a reactive terminal aldehyde group. METHODS The site-specific PEG conjugation was conducted ata slightly acidic pH condition (pH 5.5). The mono-PEGylation was targeted to an alpha-amine group at the N-terminal end of EGF to minimize reduction of biologic activity. Tryptic digestion mapping and MALDI-TOF MS techniques were applied to show the occurrence of mono-PEGylation at the N-terminus of EGF. RESULTS The site-specific mono-PEGylated EGF, when compared with native EGF, fully retained its in vitro biologic activities such a cell proliferation and intracellular signal transduction. This revealed that although a synthetic polymer of a PEG was covalently conjugated to EGF, the internalized complex of PEGylated EGF-receptor within cells did not hamper the intracellular signal transduction events. The PEGylated EGF also exhibited a prolonged circulation in blood stream in vivo and markedly enhanced physical stability whe incubated with tissue homogenate. CONCLUSION N-terminally mono-PEGylated EGF shows increased physical stability while retaining its biologic activity.
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Affiliation(s)
- Haeshin Lee
- Department of Biologic Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea
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47
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Na DH, Youn YS, Lee KC. Optimization of the PEGylation process of a peptide by monitoring with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2003; 17:2241-2244. [PMID: 14515324 DOI: 10.1002/rcm.1175] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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48
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Lee H, Park TG. A novel method for identifying PEGylation sites of protein using biotinylated PEG derivatives. J Pharm Sci 2003; 92:97-103. [PMID: 12486686 DOI: 10.1002/jps.10270] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The identification of PEGylation sites is essential in the characterization of PEGylated therapeutic proteins. This report describes a simple and novel method of finding poly(ethylene glycol) (PEG) conjugation sites in PEGylated proteins by using a hetero-functional biotin-PEG-N-hydroxyl succinimide derivative. PEGylated lysozyme species having a biotin moiety at each PEG chain end were separated and digested by trypsin. Among the digested lysozyme fragments, biotin-terminated PEGylated peptide fragments were purified by a monomeric avidin immobilized column. Their mass was analyzed by matrix-assisted laser desorption ionization time of flight mass spectrometry, directly indicating that PEG was conjugated to lysine 33, 97, 116 residues. Reversed-phase high-pressure liquid chromatography results for the PEGylated peptide fragments exhibited that PEGylation occurred preferentially at lysine 33> lysine 97> lysine 116.
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Affiliation(s)
- Haeshin Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea (South)
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Nodake Y, Iwasaki K, Yamasaki N. Interactions of a lysozyme-monomethoxypolyethylene glycol conjugate with lipopolysaccharides and lipid bilayers and effects of conjugate on gram-negative bacteria. Biosci Biotechnol Biochem 2002; 66:1848-52. [PMID: 12400682 DOI: 10.1271/bbb.66.1848] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We have been studying a lysozyme derivative, called mPEG-lysozyme, in which Lys 33 is bound with a monomethoxypolyethylene glycol derivative. Here, we examined the surface hydrophobicity of the derivative and also its interactions with lipopolysaccharides and lipid bilayers. These properties may affect the antimicrobial activity of mPEG-lysozyme toward Gram-negative microorganisms. The lysozyme derivative had more than 150% of the antimicrobial activity for such microorganisms with that of native lysozyme taken to be 100%. Spectroscopic analyses indicated that mPEG-lysozyme bound to lipopolysaccharides with higher affinity than lysozyme, because of the high surface hydrophobicity of the derivative. In an experiment on carboxyfluorescein-leakage, mPEG-lysozyme strongly interacted with liposomes constructed from phosphatidylcholine, releasing carboxyfluorescein from the liposomes more effectively than lysozyme did. mPEG-lysozyme may perturb the outer membrane of Gram-negative microorganisms, gaining itself access to the peptidoglycan layers of the bacterium.
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Affiliation(s)
- Yuichi Nodake
- Division of Bioresource and Bioenvironmental Sciences, Graduate School of Kyushu University, Fukuoka, Japan.
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50
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Lee H, Park TG. Preparation and characterization of mono-PEGylated epidermal growth factor: evaluation of in vitro biologic activity. Pharm Res 2002; 19:845-51. [PMID: 12134956 DOI: 10.1023/a:1016113117851] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE To isolate mono-PEGylated epidermal growth factor (EGF) isoforms, identify the site of PEGylation, and evaluate the biologic activity of each isoform. METHODS EGF was PEGylated with an NHS-PEG derivative (Mw 3,400). Mono-PEGylated EGF fraction was separated by gel-filtration HPLC and three mono-PEGylated EGF isoforms were purified by RP-HPLC. Tryptic digestion mapping of both EGF and mono-PEGylated EGF isoforms was performed to identify the PEGylation sites using RP-HPLC. The digested fragments were also analyzed by matrix-assisted laser desorption and ionization time of flight (MALDI-TOF) mass spectroscopy for further verification of the three PEG conjugation sites. The biologic activity of positional isoforms was evaluated by a cell proliferation assay and a receptor tyrosine kinase activity assay to determine the effect of PEGylation site on its activity. RESULTS Mono-PEGylated EGF was composed of three positional isomers. Tryptic digestion mapping and MALDI-TOF analysis permitted the identification of the PEGylated site of the three isoforms at N-terminus. Lysine 28, and Lysine 48. PEG-N-terminus EGF, among the three positional isomers, showed the highest activity in a cell proliferation assay and in a receptor-binding assay. CONCLUSION This study demonstrates that biologic activities of mono-PEGylated EGF isomers are highly dependent upon the site of PEGylation in EGF.
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Affiliation(s)
- Haeshin Lee
- Department of Biologic Sciences Korea Advanced Institute of Science and Technology, Taejon
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