Characterization of an antibody scFv that recognizes fibrillar insulin and beta-amyloid using atomic force microscopy.
Fibrillar amyloid is the hallmark feature of many protein aggregation diseases, such as Alzheimer's and Parkinson's diseases. A monoclonal single-chain variable fragment (scFv) targeting insulin fibrils was isolated using phage display technology and an atomic force microscopy (AFM) mica substrate. Specific targeting of the scFv to insulin fibrils but not monomers or other small oligomeric forms, under similar conditions, was demonstrated both by enzyme-linked immunosorbent assays and AFM recognition imaging. The scFv also recognizes beta-amyloid fibrils, a hallmark feature of Alzheimer's disease. The results suggest that the isolated scFv possibly targets a shared fibrillar motif-probably the cross-beta-sheet characteristic of amyloid fibrils. The techniques outlined here provide additional tools to further study the process of fibril formation. The scFvs isolated can have potential use as diagnostic or therapeutic reagents for protein aggregation diseases.
Marcus
Warren D
WD
Department of Physics and Astronomy, Arizona State University, Tempe, Arizona. wdmarcus@alum.mit.edu
Wang
Hongda
H
Lindsay
Stuart M
SM
Sierks
Michael R
MR
D016229:Amyloid beta-Peptides / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007128:Immunoglobulin Fragments / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D007328:Insulin / Q000276:immunology*; D018625:Microscopy, Atomic Force / Q000379:methods*; D016297:Mutagenesis, Site-Directed
D016229:Amyloid beta-Peptides; D007128:Immunoglobulin Fragments; D007328:Insulin