title: Rational design of potent domain antibody inhibitors of amyloid fibril assembly.
abstract: Antibodies hold significant potential for inhibiting toxic protein aggregation associated with conformational disorders such as Alzheimer's and Huntington's diseases. However, near-stoichiometric antibody concentrations are typically required to completely inhibit protein aggregation. We posited that the molecular interactions mediating amyloid fibril formation could be harnessed to generate antibodies with potent antiaggregation. Here we report that grafting small amyloidogenic peptides (6-10 residues) into the complementarity-determining regions of a single-domain (V(H)) antibody yields potent domain antibody inhibitors of amyloid formation. Grafted AMyloid-Motif AntiBODIES (gammabodies) presenting hydrophobic peptides from Aβ (Alzheimer's disease), α-Synuclein (Parkinson's disease), and islet amyloid polypeptide (type 2 diabetes) inhibit fibril assembly of each corresponding polypeptide at low substoichiometric concentrations (1:10 gammabody:monomer molar ratio). In contrast, sequence- and conformation-specific antibodies that were obtained via immunization are unable to prevent fibrillization at the same substoichiometric concentrations. Gammabodies prevent amyloid formation by converting monomers and/or fibrillar intermediates into small complexes that are unstructured and benign. We expect that our antibody design approach--which eliminates the need for immunization or screening to identify sequence-specific domain antibody inhibitors--can be readily extended to generate potent aggregation inhibitors of other amyloidogenic polypeptides linked to human disease.
authors.affiliation: Center for Biotechnology and Interdisciplinary Studies, Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
authors.forename: Ali Reza A
authors.initials: AR
authors.lastname: Ladiwala
authors.forename: Moumita
authors.initials: M
authors.lastname: Bhattacharya
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Perchiacca
authors.forename: Ping
authors.initials: P
authors.lastname: Cao
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Raleigh
authors.forename: Andisheh
authors.initials: A
authors.lastname: Abedini
authors.forename: Ann Marie
authors.initials: AM
authors.lastname: Schmidt
authors.forename: Jobin
authors.initials: J
authors.lastname: Varkey
authors.forename: Ralf
authors.initials: R
authors.lastname: Langen
authors.forename: Peter M
authors.initials: PM
authors.lastname: Tessier
mesh_terms: D000595:Amino Acid Sequence; D000682:Amyloid / Q000037:antagonists & inhibitors*; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D052160:Benzothiazoles; D002850:Chromatography, Gel; D002942:Circular Dichroism; D003001:Cloning, Molecular; D015195:Drug Design; D004591:Electrophoresis, Polyacrylamide Gel; D005453:Fluorescence; D006801:Humans; D015151:Immunoblotting; D058228:Islet Amyloid Polypeptide / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D008969:Molecular Sequence Data; D015202:Protein Engineering / Q000379:methods*; D061905:Single-Domain Antibodies / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D013844:Thiazoles; D051844:alpha-Synuclein / Q000378:metabolism*
chemical_list: D000682:Amyloid; D016229:Amyloid beta-Peptides; D052160:Benzothiazoles; D058228:Islet Amyloid Polypeptide; D061905:Single-Domain Antibodies; D013844:Thiazoles; D051844:alpha-Synuclein; C009462:thioflavin T