원문정보
초록
영어
Covalent conjugation of poly(ethylene glycol) to therapeutic proteins increases their in vivo stability by protecting the protein from degradation, masking its immunogenic sites and reducing clearance [1]. Frequently, PEGylation results in non-site specificity and multiple attachments, which might mask or interfere with the receptor binding sites, causing a dramatic decrease in in-vivo bioactivity. To solve this problem, site-specific PEGylation has been employed [2]. Epidermal growth factor (EGF) has been used to control and accelerate the epidermal cell's proliferation [3]. In this study, we demonstrated the thiolation of EGF using 2·iminothiolane·HCl and PEGylation with PEG-SH, which could improve the binding interaction between a protein and PEG molecules to increase the PEGylation yield. The sites of PEGylation was identified through tryptic peptide mapping and matrix assisted laser desorption-time of flight (MALDI-TOF) mass
spectrometry. Also, by RP-HPLC we could confirm the existence of tri-, di-, mono-EGF
PEGylates and their purity levels. All PEGylates were identified by native-PAGE and RP-HPLC. From 2-DE result, there was no change in isoelectric point of the thiolated EGF PEGylates.