Engineering of Bispecific Affinity Proteins with High Affinity for ERBB2 and Adaptable Binding to Albumin
2014 (English)In: PLoS ONE, ISSN 1932-6203, Vol. 9, no 8, e103094- p.Article in journal (Refereed) Published
The epidermal growth factor receptor 2, ERBB2, is a well-validated target for cancer diagnostics and therapy. Recent studies suggest that the over-expression of this receptor in various cancers might also be exploited for antibody-based payload delivery, e. g. antibody drug conjugates. In such strategies, the full-length antibody format is probably not required for therapeutic effect and smaller tumor-specific affinity proteins might be an alternative. However, small proteins and peptides generally suffer from fast excretion through the kidneys, and thereby require frequent administration in order to maintain a therapeutic concentration. In an attempt aimed at combining ERBB2-targeting with antibody-like pharmacokinetic properties in a small protein format, we have engineered bispecific ERBB2-binding proteins that are based on a small albumin-binding domain. Phage display selection against ERBB2 was used for identification of a lead candidate, followed by affinity maturation using second-generation libraries. Cell surface display and flow-cytometric sorting allowed stringent selection of top candidates from pools pre-enriched by phage display. Several affinity-matured molecules were shown to bind human ERBB2 with sub-nanomolar affinity while retaining the interaction with human serum albumin. Moreover, parallel selections against ERBB2 in the presence of human serum albumin identified several amino acid substitutions that dramatically modulate the albumin affinity, which could provide a convenient means to control the pharmacokinetics. The new affinity proteins competed for ERBB2-binding with the monoclonal antibody trastuzumab and recognized the native receptor on a human cancer cell line. Hence, high affinity tumor targeting and tunable albumin binding were combined in one small adaptable protein.
Place, publisher, year, edition, pages
2014. Vol. 9, no 8, e103094- p.
albumin, albumin binding domain derived affinity protein, epidermal growth factor receptor 2, epitope, peptides and proteins, trastuzumab, unclassified drug, amino acid sequence, amino acid substitution, antigen binding, article, binding affinity, binding site, controlled study, DNA sequence, fluorescence activated cell sorting, nonhuman, protein binding, protein domain, protein engineering, protein expression, protein protein interaction, protein purification, protein targeting
IdentifiersURN: urn:nbn:se:kth:diva-149967DOI: 10.1371/journal.pone.0103094ISI: 000339812700014ScopusID: 2-s2.0-84905457095OAI: oai:DiVA.org:kth-149967DiVA: diva2:743573
FunderSwedish Research CouncilThe Royal Swedish Academy of Sciences
QC 201409042014-09-042014-08-292016-05-10Bibliographically approved