title: Antibody recognition of a human chorionic gonadotropin epitope (hCGbeta66-80) depends on local structure retained in the free peptide.
abstract: Human chorionic gonadotropin (hCG) is an important biomarker in pregnancy and oncology, where it is routinely detected and quantified by specific immunoassays. Intelligent epitope selection is essential to achieving the required assay performance. We present binding affinity measurements demonstrating that a typical β3-loop-specific monoclonal antibody (8G5) is highly selective in competitive immunoassays and distinguishes between hCGβ(66-80) and the closely related luteinizing hormone (LH) fragment LHβ(86-100), which differ only by a single amino acid residue. A combination of optical spectroscopic measurements and atomistic computer simulations on these free peptides reveals differences in turn type stabilized by specific hydrogen bonding motifs. We propose that these structural differences are the basis for the observed selectivity in the full protein.
authors: School of Physics, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, Scotland, United Kingdom.
authors: Craig R
authors: CR
authors: Gregor
authors: Eleonora
authors: E
authors: Cerasoli
authors: James
authors: J
authors: Schouten
authors: Jascindra
authors: J
authors: Ravi
authors: Jerry
authors: J
authors: Slootstra
authors: Adrian
authors: A
authors: Horgan
authors: Glenn J
authors: GJ
authors: Martyna
authors: Maxim G
authors: MG
authors: Ryadnov
authors: Paul
authors: P
authors: Davis
authors: Jason
authors: J
authors: Crain
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