title: A Contra Capture Protein Array Platform for Studying Post-translationally Modified (PTM) Auto-antigenomes.
abstract: Aberrant modifications of proteins occur during disease development and elicit disease-specific antibody responses. We have developed a protein array platform that enables the modification of many proteins in parallel and assesses their immunogenicity without the need to express, purify, and modify proteins individually. We used anticitrullinated protein antibodies (ACPAs) in rheumatoid arthritis (RA) as a model modification and profiled antibody responses to ∼190 citrullinated proteins in 20 RA patients. We observed unique antibody reactivity patterns in both clinical anticyclic citrullinated peptide assay positive (CCP+) and CCP- RA patients. At individual antigen levels, we detected antibodies against known citrullinated autoantigens and discovered and validated five novel antibodies against specific citrullinated antigens (osteopontin (SPP1), flap endonuclease (FEN1), insulin like growth factor binding protein 6 (IGFBP6), insulin like growth factor I (IGF1) and stanniocalcin-2 (STC2)) in RA patients. We also demonstrated the utility of our innovative array platform in the identification of immune-dominant epitope(s) for citrullinated antigens. We believe our platform will promote the study of post-translationally modified antigens at a breadth that has not been achieved before, by both identifying novel autoantigens and investigating their roles in disease development. The developed platforms can potentially be used to study many autoimmune disease-relevant modifications and their immunogenicity.
authors.affiliation: From the ‡Biodesign Institute, Center for Personalized Diagnostics, Arizona State University, Tempe, Arizona 85287;
authors.forename: Kailash
authors.initials: K
authors.lastname: Karthikeyan
authors.affiliation: From the ‡Biodesign Institute, Center for Personalized Diagnostics, Arizona State University, Tempe, Arizona 85287;
authors.forename: Kristi
authors.initials: K
authors.lastname: Barker
authors.affiliation: From the ‡Biodesign Institute, Center for Personalized Diagnostics, Arizona State University, Tempe, Arizona 85287;
authors.forename: Yanyang
authors.initials: Y
authors.lastname: Tang
authors.affiliation: §Engineering Arts LLC, Phoenix, Arizona 85076;
authors.forename: Peter
authors.initials: P
authors.lastname: Kahn
authors.affiliation: From the ‡Biodesign Institute, Center for Personalized Diagnostics, Arizona State University, Tempe, Arizona 85287; §Engineering Arts LLC, Phoenix, Arizona 85076;
authors.forename: Peter
authors.initials: P
authors.lastname: Wiktor
authors.affiliation: §Engineering Arts LLC, Phoenix, Arizona 85076;
authors.forename: Al
authors.initials: A
authors.lastname: Brunner
authors.affiliation: From the ‡Biodesign Institute, Center for Personalized Diagnostics, Arizona State University, Tempe, Arizona 85287;
authors.forename: Vinicius
authors.initials: V
authors.lastname: Knabben
authors.affiliation: From the ‡Biodesign Institute, Center for Personalized Diagnostics, Arizona State University, Tempe, Arizona 85287;
authors.forename: Bharath
authors.initials: B
authors.lastname: Takulapalli
authors.affiliation: ¶Benaroya Research Institute, Seattle, Washington 98101.
authors.forename: Jane
authors.initials: J
authors.lastname: Buckner
authors.affiliation: ¶Benaroya Research Institute, Seattle, Washington 98101.
authors.forename: Gerald
authors.initials: G
authors.lastname: Nepom
authors.affiliation: From the ‡Biodesign Institute, Center for Personalized Diagnostics, Arizona State University, Tempe, Arizona 85287;
authors.forename: Joshua
authors.initials: J
authors.lastname: LaBaer
authors.affiliation: From the ‡Biodesign Institute, Center for Personalized Diagnostics, Arizona State University, Tempe, Arizona 85287; Ji.Qiu@asu.edu.
authors.forename: Ji
authors.initials: J
authors.lastname: Qiu
mesh_terms: D001172:Arthritis, Rheumatoid / Q000276:immunology*; D001323:Autoantibodies / Q000378:metabolism*; D001324:Autoantigens / Q000276:immunology; D000939:Epitopes / Q000276:immunology; D006801:Humans; D010456:Peptides, Cyclic / Q000276:immunology*; D040081:Protein Array Analysis / Q000379:methods*; D011499:Protein Processing, Post-Translational
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D000939:Epitopes; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide