Affimer reagents enable targeted delivery of therapeutic agents and RNA via virus-like particles
Sophie E. Roberts,
Heather L. Martin,
Danah Al-Qallaf,
Anna A. Tang,
Christian Tiede,
Thembaninkosi G. Gaule,
Albor Dobon-Alonso,
Ross Overman,
Sachin Shah,
Hadrien Peyret,
Keith Saunders,
Robin Bon,
Iain W. Manfield,
Sandra M. Bell,
George P. Lomonossoff,
Valerie Speirs,
Darren C. Tomlinson
Affiliations
Sophie E. Roberts
School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
Heather L. Martin
School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
Danah Al-Qallaf
School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
Anna A. Tang
School of Molecular and Cellular Biology, University of Leeds, Leeds, UK; Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds, UK
Christian Tiede
School of Molecular and Cellular Biology, University of Leeds, Leeds, UK; Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds, UK
Thembaninkosi G. Gaule
Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds, UK; Institutue of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds, UK
Albor Dobon-Alonso
Leaf Expression Systems, Norwich Research Park, Norwich, UK
Ross Overman
Leaf Expression Systems, Norwich Research Park, Norwich, UK
Sachin Shah
Department of Biochemistry and Metabolism, John Innes Centre, Norwich Research Park, Norwich, UK
Hadrien Peyret
Department of Biochemistry and Metabolism, John Innes Centre, Norwich Research Park, Norwich, UK
Keith Saunders
Department of Biochemistry and Metabolism, John Innes Centre, Norwich Research Park, Norwich, UK
Robin Bon
Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds, UK; Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds, UK
Iain W. Manfield
School of Molecular and Cellular Biology, University of Leeds, Leeds, UK; Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds, UK
Sandra M. Bell
Leeds Institute of Medical Research at St James’s, St James’s University Hospital, University of Leeds, Leeds, UK
George P. Lomonossoff
Department of Biochemistry and Metabolism, John Innes Centre, Norwich Research Park, Norwich, UK
Valerie Speirs
Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
Darren C. Tomlinson
School of Molecular and Cellular Biology, University of Leeds, Leeds, UK; Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds, UK; Corresponding author
Summary: Monoclonal antibodies have revolutionized therapies, but non-immunoglobulin scaffolds are becoming compelling alternatives owing to their adaptability. Their ability to be labeled with imaging or cytotoxic compounds and to create multimeric proteins is an attractive strategy for therapeutics. Focusing on HER2, a frequently overexpressed receptor in breast cancer, this study addresses some limitations of conventional targeting moieties by harnessing the potential of these scaffolds. HER2-binding Affimers were isolated and characterized, demonstrating potency as binding reagents and efficient internalization by HER2-overexpressing cells. Affimers conjugated with cytotoxic agent achieved dose-dependent reductions in cell viability within HER2-overexpressing cell lines. Bispecific Affimers, targeting HER2 and virus-like particles, facilitated efficient internalization of virus-like particles carrying enhanced green fluorescent protein (eGFP)-encoding RNA, leading to protein expression. Anti-HER2 affibody or designed ankyrin repeat protein (DARPin) fusion constructs with the anti-VLP Affimer further underscore the adaptability of this approach. This study demonstrates the versatility of scaffolds for precise delivery of cargos into cells, advancing biotechnology and therapeutic research.