1
|
Lam SF, Shang X, Ghosh R. Membrane-Based Hybrid Method for Purifying PEGylated Proteins. MEMBRANES 2023; 13:182. [PMID: 36837684 PMCID: PMC9966431 DOI: 10.3390/membranes13020182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/18/2023] [Accepted: 01/30/2023] [Indexed: 06/18/2023]
Abstract
PEGylated proteins are usually purified using chromatographic methods, which are limited in terms of both speed and scalability. In this paper, we describe a microfiltration membrane-based hybrid method for purifying PEGylated proteins. Polyethylene glycol (or PEG) is a lower critical solution temperature polymer which undergoes phase transition in the presence of a lyotropic salt and forms micelle-like structures which are several microns in size. In the proposed hybrid method, the PEGylated proteins are first converted to their micellar form by the addition of a lyotropic salt (1.65 M ammonium sulfate). While the micelles are retained using a microfiltration membrane, soluble impurities such as the unmodified protein are washed out through the membrane. The PEGylated proteins thus retained by the membrane are recovered by solubilizing them by removing the lyotropic salt. Further, by precisely controlling the salt removal, the different PEGylated forms of the protein, i.e., mono-PEGylated and di-PEGylated forms, are fractionated from each other. Hybrid separation using two different types of microfiltration membrane devices, i.e., a stirred cell and a tangential flow filtration device, are examined in this paper. The membrane-based hybrid method for purifying PEGylated proteins is both fast and scalable.
Collapse
Affiliation(s)
| | | | - Raja Ghosh
- Correspondence: ; Tel.: +1-905-525-9140 (ext. 27415)
| |
Collapse
|
2
|
Mao L, Russell AJ, Carmali S. Moving Protein PEGylation from an Art to a Data Science. Bioconjug Chem 2022; 33:1643-1653. [PMID: 35994522 PMCID: PMC9501918 DOI: 10.1021/acs.bioconjchem.2c00262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
PEGylation is a well-established and clinically proven
half-life
extension strategy for protein delivery. Protein modification with
amine-reactive poly(ethylene glycol) (PEG) generates heterogeneous
and complex bioconjugate mixtures, often composed of several PEG positional
isomers with varied therapeutic efficacy. Laborious and costly experiments
for reaction optimization and purification are needed to generate
a therapeutically useful PEG conjugate. Kinetic models which accurately
predict the outcome of so-called “random” PEGylation
reactions provide an opportunity to bypass extensive wet lab experimentation
and streamline the bioconjugation process. In this study, we propose
a protein tertiary structure-dependent reactivity model that describes
the rate of protein-amine PEGylation and introduces “PEG chain
coverage” as a tangible metric to assess the shielding effect
of PEG chains. This structure-dependent reactivity model was implemented
into three models (linear, structure-based, and machine-learned) to
gain insight into how protein-specific molecular descriptors (exposed
surface areas, pKa, and surface charge)
impacted amine reactivity at each site. Linear and machine-learned
models demonstrated over 75% prediction accuracy with butylcholinesterase.
Model validation with Somavert, PEGASYS, and phenylalanine ammonia
lyase showed good correlation between predicted and experimentally
determined degrees of modification. Our structure-dependent reactivity
model was also able to simulate PEGylation progress curves and estimate
“PEGmer” distribution with accurate predictions across
different proteins, PEG linker chemistry, and PEG molecular weights.
Moreover, in-depth analysis of these simulated reaction curves highlighted
possible PEG conformational transitions (from dumbbell to brush) on the surface of lysozyme, as a function
of PEG molecular weight.
Collapse
Affiliation(s)
- Leran Mao
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Alan J Russell
- Amgen Inc., Thousand Oaks, California 91320, United States
| | - Sheiliza Carmali
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL United Kingdom
| |
Collapse
|
3
|
Sánchez-Trasviña C, Flores-Gatica M, Enriquez-Ochoa D, Rito-Palomares M, Mayolo-Deloisa K. Purification of Modified Therapeutic Proteins Available on the Market: An Analysis of Chromatography-Based Strategies. Front Bioeng Biotechnol 2021; 9:717326. [PMID: 34490225 PMCID: PMC8417561 DOI: 10.3389/fbioe.2021.717326] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Accepted: 08/09/2021] [Indexed: 02/02/2023] Open
Abstract
Proteins, which have inherent biorecognition properties, have long been used as therapeutic agents for the treatment of a wide variety of clinical indications. Protein modification through covalent attachment to different moieties improves the therapeutic's pharmacokinetic properties, affinity, stability, confers protection against proteolytic degradation, and increases circulation half-life. Nowadays, several modified therapeutic proteins, including PEGylated, Fc-fused, lipidated, albumin-fused, and glycosylated proteins have obtained regulatory approval for commercialization. During its manufacturing, the purification steps of the therapeutic agent are decisive to ensure the quality, effectiveness, potency, and safety of the final product. Due to the robustness, selectivity, and high resolution of chromatographic methods, these are recognized as the gold standard in the downstream processing of therapeutic proteins. Moreover, depending on the modification strategy, the protein will suffer different physicochemical changes, which must be considered to define a purification approach. This review aims to deeply analyze the purification methods employed for modified therapeutic proteins that are currently available on the market, to understand why the selected strategies were successful. Emphasis is placed on chromatographic methods since they govern the purification processes within the pharmaceutical industry. Furthermore, to discuss how the modification type strongly influences the purification strategy, the purification processes of three different modified versions of coagulation factor IX are contrasted.
Collapse
Affiliation(s)
- Calef Sánchez-Trasviña
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Centro de Biotecnología-FEMSA, Monterrey, Mexico
| | - Miguel Flores-Gatica
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Centro de Biotecnología-FEMSA, Monterrey, Mexico
| | - Daniela Enriquez-Ochoa
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Centro de Biotecnología-FEMSA, Monterrey, Mexico
| | - Marco Rito-Palomares
- Tecnologico de Monterrey, Escuela de Medicina y Ciencias de la Salud, Monterrey, Mexico
| | - Karla Mayolo-Deloisa
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Centro de Biotecnología-FEMSA, Monterrey, Mexico
| |
Collapse
|
4
|
Perspectives, Tendencies, and Guidelines in Affinity-Based Strategies for the Recovery and Purification of PEGylated Proteins. ADVANCES IN POLYMER TECHNOLOGY 2020. [DOI: 10.1155/2020/6163904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In recent years, the effective purification of PEGylated therapeutic proteins from reaction media has received particular attention. Although several techniques have been used, affinity-based strategies have been scarcely explored despite the fact that, after PEGylation, marked changes in the molecular affinity parameters of the modified molecules are observed. With this in mind, future contributions in the bioseparation of these polymer-protein conjugates are expected to exploit affinity in chromatographic and nonchromatographic techniques which will surely derive in the integration of different operations. However, this will only occur as novel ligands which are simultaneously found. As it will be mentioned, these novel ligands may be screened or designed. In both cases, computer-aided tools will support their identification or development. Additionally, ligand discovery by high-throughput screening (HTS) is believed to become a fast, economic, and informative technology that will aid in the mass production of ligands along with genetic engineering and related technologies. Therefore, besides analyzing the state of the art in affinity separation strategies for PEGylated molecules, this review proposes a basic guideline for the selection of adequate ligands to provide information and prospective on the future of affinity operations in solving this particular bioengineering problem.
Collapse
|
5
|
Munasinghe A, Mathavan A, Mathavan A, Lin P, Colina CM. PEGylation within a confined hydrophobic cavity of a protein. Phys Chem Chem Phys 2019; 21:25584-25596. [PMID: 31720639 DOI: 10.1039/c9cp04387j] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The conjugation of polyethylene glycol (PEG) to proteins, known as PEGylation, has increasingly been employed to expand the efficacy of therapeutic drugs. Recently, research has emphasized the effect of the conjugation site on protein-polymer interactions. In this study, we performed atomistic molecular dynamics (MD) simulations of lysine 116 PEGylated bovine serum albumin (BSA) to illustrate how conjugation near a hydrophobic pocket affects the conjugate's dynamics and observed altered low mode vibrations in the protein. MD simulations were performed for a total of 1.5 μs for each PEG chain molecular mass from 2 to 20 kDa. Analysis of preferential PEG-BSA interactions showed that polymer behavior was also affected as proximity to the attractive protein surface patches promoted interactions in small (2 kDa) PEG chains, while the confined environment of the conjugation site reduced the expected BSA surface coverage when the polymer molecular mass increased to 10 kDa. This thorough analysis of PEG-BSA interactions and polymer dynamics increases the molecular understanding of site-specific PEGylation and enhances the use of protein-polymer conjugates as therapeutics.
Collapse
Affiliation(s)
- Aravinda Munasinghe
- Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
| | | | | | | | | |
Collapse
|
6
|
Chen G, Song W, Qi B, Ghosh R, Wan Y. Separation of human serum albumin and polyethylene glycol by electro-ultrafiltration. Biochem Eng J 2016. [DOI: 10.1016/j.bej.2016.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
7
|
Tan TRM, Hoi KM, Zhang P, Ng SK. Characterization of a Polyethylene Glycol-Amphotericin B Conjugate Loaded with Free AMB for Improved Antifungal Efficacy. PLoS One 2016; 11:e0152112. [PMID: 27008086 PMCID: PMC4805162 DOI: 10.1371/journal.pone.0152112] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 03/09/2016] [Indexed: 11/18/2022] Open
Abstract
Amphotericin B (AMB) is a highly hydrophobic antifungal, whose use is limited by its toxicity and poor solubility. To improve its solubility, AMB was reacted with a functionalized polyethylene glycol (PEG), yielding soluble complex AmB-PEG formulations that theoretically comprise of chemically conjugated AMB-PEG and free AMB that is physically associated with the conjugate. Reverse-phase chromatography and size exclusion chromatography methods using HPLC were developed to separate conjugated AMB-PEG and free AmB, enabling the further characterization of these formulations. Using HPLC and dynamic light scattering analyses, it was observed that the AMB-PEG 2 formulation, having a higher molar ratio of 2 AMB: 1 PEG, possesses more free AMB and has relatively larger particle diameters compared to the AMB-PEG 1 formulation, that consists of 1 AMB: 1 PEG. The identity of the conjugate was also verified using mass spectrometry. AMB-PEG 2 demonstrates improved antifungal efficacy relative to AMB-PEG 1, without a concurrent increase in in vitro toxicity to mammalian cells, implying that the additional loading of free AMB in the AMB-PEG formulation can potentially increase its therapeutic index. Compared to unconjugated AMB, AMB-PEG formulations are less toxic to mammalian cells in vitro, even though their MIC50 values are comparatively higher in a variety of fungal strains tested. Our in vitro results suggest that AMB-PEG 2 formulations are two times less toxic than unconjugated AMB with antifungal efficacy on Candida albicans and Cryptococcus neoformans.
Collapse
Affiliation(s)
- Tessa Rui Min Tan
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Kong Meng Hoi
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Peiqing Zhang
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Say Kong Ng
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
- Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore, Singapore
| |
Collapse
|
8
|
Baumann A, Tuerck D, Prabhu S, Dickmann L, Sims J. Pharmacokinetics, metabolism and distribution of PEGs and PEGylated proteins: quo vadis? Drug Discov Today 2014; 19:1623-31. [PMID: 24929223 DOI: 10.1016/j.drudis.2014.06.002] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 05/02/2014] [Accepted: 06/04/2014] [Indexed: 11/19/2022]
Abstract
The pharmacokinetics (PK), metabolism and biodistribution of polyethylene glycol (PEG) in PEGylated proteins are important to understand the increased cellular vacuolation reported in various tissues in animals. The tissue distribution profile of PEGylated proteins and 'metabolic' PEG is guided largely by absolute PEG load, PEG molecular weight and, where applicable, receptor-mediated uptake via the protein moiety. High molecular weight PEGs show slow renal clearance, and consequently have a greater potential to accumulate within cells. The intracellular nonbiodegradable PEG can accumulate within the lysosome ultimately causing distension and vacuolation observed by standard histological examinations. Improved bioanalytical methodologies will contribute to the identification of specific PK parameters including distribution behavior to support development of PEGylated proteins as therapeutics.
Collapse
|
9
|
Ruanjaikaen K, Zydney AL. Intermolecular interactions during ultrafiltration of pegylated proteins. Biotechnol Prog 2013; 29:655-63. [PMID: 23436792 DOI: 10.1002/btpr.1709] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 01/27/2013] [Indexed: 11/10/2022]
Abstract
Recent studies have demonstrated the feasibility of using membrane ultrafiltration for the purification of pegylated proteins; however, the separations have all been performed at relatively low protein concentrations where intermolecular interactions are unimportant. The objective of this study was to examine the behavior at higher PEG concentrations and to develop an appropriate theoretical framework to describe the effects of intermolecular interactions. Ultrafiltration experiments were performed using pegylated α-lactalbumin as a model protein with both neutral and charged composite regenerated cellulose membranes. The transmission of the pegylated α-lactalbumin, PEG, and α-lactalbumin all increase with increasing PEG concentration due to the increase in the solute partition coefficient arising from unfavorable intermolecular interactions in the bulk solution. The experimental results were in good agreement with a simple model that accounts for the change in Gibbs free energy associated with these intermolecular interactions, including the effects of concentration polarization on the local solute concentrations upstream of the membrane. These intermolecular interactions are shown to cause a greater than expected loss of pegylated product in a batch ultrafiltration system, and they alter the yield and purification factor that can be achieved during a diafiltration process to remove unreacted PEG.
Collapse
Affiliation(s)
- Krisada Ruanjaikaen
- Dept. of Chemical Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | | |
Collapse
|
10
|
González M, Grau RJ, Vaillard SE. New method for the synthesis and purification of branched mPEG2lys. REACT FUNCT POLYM 2012. [DOI: 10.1016/j.reactfunctpolym.2011.10.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
|
11
|
Pai SS, Hammouda B, Hong K, Pozzo DC, Przybycien TM, Tilton RD. The Conformation of the Poly(ethylene glycol) Chain in Mono-PEGylated Lysozyme and Mono-PEGylated Human Growth Hormone. Bioconjug Chem 2011; 22:2317-23. [DOI: 10.1021/bc2003583] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Boualem Hammouda
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg,
Maryland 20899, United States
| | - Kunlun Hong
- Center for Nanophase Materials
Sciences and Chemical Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Danilo C. Pozzo
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195,
United States
| | | | | |
Collapse
|
12
|
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.
Collapse
|
13
|
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]
|
14
|
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.
Collapse
Affiliation(s)
- Krisada Ruanjaikaen
- Department of Chemical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | | |
Collapse
|
15
|
Affiliation(s)
- Simona Jevsevar
- Lek Pharmaceuticals d.d., a Sandoz Company, Biopharmaceuticals, Ljubljana, Slovenia.
| | | | | |
Collapse
|
16
|
Aimar P, Meireles M. Calibration of ultrafiltration membranes against size exclusion chromatography columns. J Memb Sci 2010. [DOI: 10.1016/j.memsci.2009.09.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
17
|
Latulippe DR, Molek JR, Zydney AL. Importance of Biopolymer Molecular Flexibility in Ultrafiltration Processes. Ind Eng Chem Res 2008. [DOI: 10.1021/ie8005337] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- David R. Latulippe
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Jessica R. Molek
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Andrew L. Zydney
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802
| |
Collapse
|
18
|
Cheng YC, Bianco CL, Sandler SI, Lenhoff AM. Salting-Out of Lysozyme and Ovalbumin from Mixtures: Predicting Precipitation Performance from Protein−Protein Interactions. Ind Eng Chem Res 2008. [DOI: 10.1021/ie071462p] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yu-Chia Cheng
- Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716
| | - Carolina L. Bianco
- Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716
| | - Stanley I. Sandler
- Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716
| | - Abraham M. Lenhoff
- Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716
| |
Collapse
|
19
|
Veronese FM, Pasut G. PEGylation: Posttranslational bioengineering of protein biotherapeutics. DRUG DISCOVERY TODAY. TECHNOLOGIES 2008; 5:e57-e64. [PMID: 24981092 DOI: 10.1016/j.ddtec.2009.02.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Polymer conjugation, especially by poly(ethylene glycol), has become a leading technology for the delivery of proteins. Nowadays, biotech drugs represent an increasing share of the new approved drugs, but their use is often prevented by drawbacks and safety concern. In particular, short in vivo half-life and immunogenicity are significant problems faced by the researchers dealing with the development of protein and peptide drugs. The chemical linking of a polymer to the protein surface has proved effective in prolonging protein blood circulation and reducing the immunogenicity by decreasing renal clearance and shielding immunogenic epitopes, respectively. So far, PEGylation has already led to nine marketed conjugates with great therapeutic success.:
Collapse
Affiliation(s)
- Francesco M Veronese
- Department of Pharmaceutical Sciences, University of Padua, via F. Marzolo 5, 35131 Padua, Italy.
| | - Gianfranco Pasut
- Department of Pharmaceutical Sciences, University of Padua, via F. Marzolo 5, 35131 Padua, Italy.
| |
Collapse
|
20
|
Fee CJ. Size comparison between proteins PEGylated with branched and linear poly(ethylene glycol) molecules. Biotechnol Bioeng 2007; 98:725-31. [PMID: 17461424 DOI: 10.1002/bit.21482] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Therapeutic proteins conjugated with branched poly(ethylene glycol) (PEG) have extended in vivo circulation half-lives compared to linear PEG-proteins, thought to be due partly to a greater hydrodynamic volume of branched PEG-proteins, which reduces the glomerular sieving coefficient. In this paper, viscosity radii of PEGylated alpha-lactalbumin (M(r) = 14.2 kDa) and bovine serum albumin (M(r) = 67 kDa) prepared with linear and branched PEGs (with nominal molecular weights 5, 10, 20 and 40 kDa) were compared experimentally using size exclusion chromatography (SEC). PEG adduct:protein molecular weight ratios of the PEGylated proteins covered the range 1:12 to 6:1. Direct comparisons of experimentally measured viscosity radii were found to be misleading due to differences between actual and nominal molecular weights of the PEG reagents used. Comparison with predicted viscosity radii shows that there is no significant difference between the viscosity radii of branched and linear PEG-proteins having the same total molecular weight of PEG adducts. Therefore, longer in vivo circulation half-lives of branched PEG-proteins compared to linear PEG-proteins are not explained by size difference. It is also calculated that the molecular size cut-off for glomerular filtration, 60 A for a 30 kDa PEG, matches the 30-50 A size range for the pores of the glomerular basement membrane. Finally, it is confirmed that prediction of PEG-protein viscosity radii should be based upon conservation of the total PEG adduct surface area to volume ratio for both linear and branched PEG-proteins regardless of PEGylation extent.
Collapse
Affiliation(s)
- Conan J Fee
- Department of Chemical & Process Engineering, University of Canterbury, Private Bag 4800, Christchurch 8020, New Zealand.
| |
Collapse
|
21
|
Asgeirsson D, Venturoli D, Fries E, Rippe B, Rippe C. Glomerular sieving of three neutral polysaccharides, polyethylene oxide and bikunin in rat. Effects of molecular size and conformation. Acta Physiol (Oxf) 2007; 191:237-46. [PMID: 17935524 DOI: 10.1111/j.1748-1716.2007.01733.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM Polysaccharides and many other non-protein polymers generally have a more open, flexible and asymmetrical structure compared with globular proteins. For a given molecular weight (MW), the Stokes-Einstein radius (a(e)) of the following polymers increases in the order: Ficoll < dextran <or= pullulan < polyethylene oxide (PEO). We have tested the hypothesis that such an increase in 'molecular extension' will increase the molecule's glomerular permeability. Thus, we investigated the glomerular sieving coefficients (theta) of the mentioned polymers and of the negatively charged and extended protein bikunin. METHODS In anaesthetized Wistar rats, glomerular sieving curves were generated for each FITC-labelled polymer from their respective concentration in urine and plasma, determined by size exclusion chromatography. The theta for bikunin was measured using a tissue uptake technique. RESULTS For a molecule of a(e) = 55 A (cf. IgG), theta increased in the order: Ficoll (0.00035 +/- 0.000013) < dextran (0.022 +/- 0.0029) < pullulan (0.033 +/- 0.0024) < PEO (0.12 +/- 0.0055). For a(e) = 36 A (cf. albumin) the order was: Ficoll (0.076 +/- 0.0061) < dextran (0.45 +/- 0.037) = pullulan (0.45 +/- 0.021) < PEO (0.65 +/- 0.0076). theta for bikunin (0.089 +/- 0.0045) was 150 times higher than that of albumin, having an equivalent a(e) and net negative charge. CONCLUSION From these results it is concluded that for flexible and asymmetric macromolecules, their degree of glomerular hyperpermeability is proportional to their degree of 'molecular extension'. Thus, compared with globular proteins, the polysaccharides investigated, including Ficoll, were found to be hyperpermeable across the glomerular filter in vivo.
Collapse
Affiliation(s)
- D Asgeirsson
- Department of Nephrology, Clinical Sciences, University Hospital of Lund, Lund, Sweden.
| | | | | | | | | |
Collapse
|
22
|
Monitoring the structural alterations induced in β-lactoglobulin during ultrafiltration: learning from chemical and thermal denaturation phenomena. J Memb Sci 2007. [DOI: 10.1016/j.memsci.2007.05.027] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
23
|
Pabst TM, Buckley JJ, Ramasubramanyan N, Hunter AK. Comparison of strong anion-exchangers for the purification of a PEGylated protein. J Chromatogr A 2007; 1147:172-82. [PMID: 17346720 DOI: 10.1016/j.chroma.2007.02.051] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2006] [Revised: 02/12/2007] [Accepted: 02/15/2007] [Indexed: 11/20/2022]
Abstract
We have studied the effect of protein PEGylation on ion-exchange adsorption using bovine serum albumin as a model system. The free sulfhydryl group of BSA, located on cysteine 34, was PEGylated using the maleimido-PEG chemistry. Several different BSA preparations were screened for extent of reaction using a 30 kDa PEG reagent. The highest yielding BSA preparation was PEGylated using linear 12 kDa and 30 kDa PEG reagents at the 1 liter scale. The PEGylated reaction mixture was purified by anion-exchange gradient elution chromatography to remove native protein and aggregates. Purity following anion-exchange chromatography was >90% as determined by analytical size exclusion chromatography. The elution salt concentration decreased with increasing PEG chain length. Breakthrough studies on six commercially available anion-exchange stationary phases with purified PEG-BSA conjugates confirm a very large decrease in dynamic binding capacity compared to the native protein. The decrease in dynamic binding capacity is likely due to modulation of electrostatic interactions caused by the neutral PEG chain and increased mass transfer resistance associated with the large size of the molecule. Of the stationary phases evaluated, the open porous structure of the agarose based ion-exchangers resulted in the highest dynamic binding capacities for the PEG-BSA conjugates. Frontal analysis experiments demonstrate use of this technique for purification of PEGylated proteins. A stationary phase that tended to exclude the large PEG-BSA conjugate was very efficient in removing native protein from a crude reaction mixture by frontal analysis.
Collapse
Affiliation(s)
- Timothy M Pabst
- Pfizer Inc., Global Biologics, 700 Chesterfield Village Parkway, Chesterfield, MO 63017, USA
| | | | | | | |
Collapse
|