Cooper, Chris E and Bird, M and Sheng, X and Simons, M and Ronda, L and Mozzarelli, A and Reeder, Brandon J (2022) Stability of a Novel PEGylation Site on a Putative Haemoglobin-Based Oxygen Carrier. In: Oxygen Transport to Tissue XLIII, 2021-07-27 - 2021-07-30, Online.
Cooper, Chris E and Bird, M and Sheng, X and Simons, M and Ronda, L and Mozzarelli, A and Reeder, Brandon J (2022) Stability of a Novel PEGylation Site on a Putative Haemoglobin-Based Oxygen Carrier. In: Oxygen Transport to Tissue XLIII, 2021-07-27 - 2021-07-30, Online.
Cooper, Chris E and Bird, M and Sheng, X and Simons, M and Ronda, L and Mozzarelli, A and Reeder, Brandon J (2022) Stability of a Novel PEGylation Site on a Putative Haemoglobin-Based Oxygen Carrier. In: Oxygen Transport to Tissue XLIII, 2021-07-27 - 2021-07-30, Online.
Abstract
PEGylation of protein sulfhydryl residues is a common method used to create a stable drug conjugate to enhance vascular retention times. We recently created a putative haemoglobin-based oxygen carrier using maleimide-PEG to selectively modify a single engineered cysteine residue in the α subunit (αAla19Cys). However, maleimide-PEG adducts are subject to deconjugation via retro-Michael reactions, with consequent cross-conjugation to endogenous plasma thiols such as those found on human serum albumin or glutathione. In previous studies mono-sulfone-PEG adducts have been shown to be less susceptible to deconjugation. We therefore compared the stability of our maleimide-PEG Hb adduct with one created using a mono-sulfone PEG. The corresponding mono-sulfone-PEG adduct was significantly more stable when incubated at 37 °C for 7 days in the presence of 1 mM reduced glutathione, 20 mg/mL human serum albumin, or human serum. In all cases haemoglobin treated with mono-sulfone-PEG retained >90% of its conjugation whereas maleimide-PEG showed significant deconjugation, especially in the presence of 1 mM reduced glutathione where <70% of the maleimide-PEG conjugate remained intact. Although maleimide-PEGylation of Hb seems adequate for an oxygen therapeutic intended for acute use, if longer vascular retention is required reagents such as mono-sulfone-PEG may be more appropriate.
Item Type: | Conference or Workshop Item (Paper) |
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Uncontrolled Keywords: | Excipients; Glutathione; Hemoglobins; Humans; Maleimides; Oxygen; Polyethylene Glycols; Serum Albumin, Human; Sulfhydryl Compounds |
Divisions: | Faculty of Science and Health Faculty of Science and Health > Life Sciences, School of |
SWORD Depositor: | Unnamed user with email elements@essex.ac.uk |
Depositing User: | Unnamed user with email elements@essex.ac.uk |
Date Deposited: | 10 Mar 2025 11:33 |
Last Modified: | 10 Mar 2025 11:37 |
URI: | http://repository.essex.ac.uk/id/eprint/36304 |
Available files
Filename: 2022 AEMB.pdf
Licence: Creative Commons: Attribution 4.0