Biotin receptor-mediated intracellular delivery of synthetic polypeptide-protein complexes

Li, H.; Bruce, G.; Childerhouse, N.; Keegan, G.; Mantovani, G.; Stolnik, S.

Abstract

Pulmonary delivery offers a non-invasive route for the administration of biotherapeutics. In this context, understanding and control of a transport into, and across cellular barriers is central to the design of delivery systems. Here, we report our study on receptor mediated delivery of protein cargo by a formulation comprising sub-300 nm sized non-covalent protein complexes with biotin-conjugated PEG-poly(glutamic acid) (biotin-PEG2k-b-GA10) and PEG2k-b-GA30 copolymers blend as targeting and complexing functionalities. Designed complexes achieve intracellular delivery of the cargo in lung derived A549 epithelial cells in vitro via sodium-dependent multivitamin transporter (biotin receptor). We further show that biotin receptor driven endocytosis preferentially involves dynamin- and caveolae-dependent vesicular internalization, switching the transport pathway away from predominantly clathrin-dependent entry of free protein. Significantly for a protective intracellular delivery of biotherapeutics based on non-covalent complexation with polymeric excipients, the study provides evidence of intracellular presence of the complexing copolymer; demonstrated exploiting biotin in biotin-PEG2k-b-GA10 copolymer as a tag for binding with fluorescently labelled avidin. Moreover, analysis of intracellular localization of constitutive species shortly following cellular internalization suggests a co-localization of biotin-PEG2k-b-GA10 copolymer and protein constitutive species. The study demonstrates intracellular delivery of biotin targeted non-covalent complexes with a protein cargo, the result with important implications in a design of enabling technology platforms for protective, receptor mediated intracellular delivery of biotherapeutics.

Citation

Li, H., Bruce, G., Childerhouse, N., Keegan, G., Mantovani, G., & Stolnik, S. (2023). Biotin receptor-mediated intracellular delivery of synthetic polypeptide-protein complexes. Journal of Controlled Release, 357, 333-341. https://doi.org/10.1016/j.jconrel.2023.03.051

• Journal Article Type: Article
• Acceptance Date: May 1, 2023
• Online Publication Date: Apr 8, 2023
• Publication Date: May 1, 2023
• Deposit Date: Apr 1, 2025
• Publicly Available Date: Apr 8, 2025
• Journal: Journal of Controlled Release
• Print ISSN: 0168-3659
• Electronic ISSN: 1873-4995
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 357
• Article Number: https://doi.org/10.1016/j.jconrel.2023.03.051
• Pages: 333-341
• DOI: https://doi.org/10.1016/j.jconrel.2023.03.051
• Keywords: Intracellular protein delivery, Polymer complexes, Biotin targeting, Endocytosis, Lung delivery
• Public URL: https://nottingham-repository.worktribe.com/output/47272086
• Publisher URL: https://doi.org/10.1016/j.jconrel.2023.03.051
• Other Repo URL: https://doi.org/10.1016/j.jconrel.2023.03.051