Motif-Grafted Antibodies Containing the Replicative Interface of Cellular PrP Are Specific for PrPSc

• Published in: Proceedings of the National Academy of Sciences - PNAS 2004-07, Vol.101 (28), p.10404-10409
• Main Authors: Moroncini, Gianluca, Kanu, Nnennaya, Solforosi, Laura, Abalos, Gil, Telling, Glenn C., Head, Mark, Ironside, James, Brockes, Jeremy P., Burton, Dennis R., Williamson, R. Anthony, Chanock, Robert M.
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Antibodies; Antibodies, Monoclonal - genetics; Antibodies, Monoclonal - immunology; Antibody Specificity; Antigens; Biological Sciences; Creutzfeldt Jakob syndrome; Creutzfeldt-Jakob Syndrome - immunology; Cricetinae; Epitopes; Epitopes - genetics; Epitopes - immunology; Homogenization; Humans; Immunoglobulin G - genetics; Immunoglobulin G - immunology; Immunology; Immunoprecipitation; Mice; Molecular Sequence Data; Molecules; Prions; PrPC Proteins - genetics; PrPC Proteins - immunology; PrPSc Proteins - genetics; PrPSc Proteins - immunology; Reactivity; Scrapie - immunology; Spongiform encephalopathies; Tissue grafting
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.0403522101

Prion diseases are closely associated with the conversion of the cellular prion protein ( PrPC) to an abnormal conformer ( PrPSc) [Prusiner, S. B. (1998) Proc. Natl. Acad. Sci. USA 95, 13363-13383]. Monoclonal antibodies that bind epitopes comprising residues 96-104 and 133-158 of PrPCpotently inhibit this process, presumably by preventing heterodimeric association of PrPCand PrPSc, and suggest that these regions of PrPCmay be critical components of the PrPC- PrPScreplicative interface. We reasoned that transplanting PrP sequence corresponding to these regions into a suitable carrier molecule, such as an antibody, could impart specific recognition of disease-associated forms of PrP. To test this hypothesis, polypeptides containing PrP sequence between residues 89-112 or 136-158 were used to replace the extended heavy chain complementarity-determining region 3 of an IgG antibody specific for the envelope glycoprotein of HIV-1. Herein the resulting engineered PrP-IgGs are shown to bind specifically to infective fractions of PrP in mouse, human, and hamster prion-infected tissues, but not to PrPC, other cellular components, or the HIV-1 envelope. PrPScreactivity was abolished when the sequence of the PrP 89-112 and 136-158 grafts was mutated, scrambled, or N-terminally truncated. Our findings suggest that residues within the 89-112 and 136-158 segments of PrPCare key components of one face of the PrPC- PrPSccomplex. PrPSc-specific antibodies produced by the approach described may find widespread application in the study of prion biology and replication and in the detection of infectious prions in human and animal materials.