title: Establishment of a simple and quantitative immunospot assay for detecting anti-type II collagen antibody using an infrared fluorescence imaging system (IFIS).
abstract: Antibodies to type II collagen (col II) have been detected in patients with rheumatoid arthritis and in animal models of collagen induced arthritis. Here, we describe a novel method to detect anti-col II antibodies using an immunospot assay with an infrared fluorescence imaging system. This method showed very high sensitivity and specificity, and was simple, with low background levels. It also showed higher reproducibility and linearity, with a dynamic range of approximately 500-fold, than the conventional immunospot assay with enhanced chemiluminescence detection. Using this method we were able to demonstrate the antibody affinity maturation process in mice immunized with col II. In these immunized mice, although cross-reactive antibodies reacting with other collagen species were detected in earlier stages of immunization, the titers of cross-reactive antibodies rapidly diminished after the antigen boost, concomitantly with the elevation of the anti-col II antibody. The method and its possible applications are discussed.
authors.affiliation: Department of Molecular and Cellular Biology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan.
authors.forename: Shusuke
authors.initials: S
authors.lastname: Ota
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kanazawa
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Takanobu
authors.initials: T
authors.lastname: Otsuka
authors.forename: Takashi
authors.initials: T
authors.lastname: Okamoto
mesh_terms: D000818:Animals; D000915:Antibody Affinity / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000175:diagnosis* / Q000276:immunology; D001323:Autoantibodies / Q000097:blood*; D024043:Collagen Type II / Q000276:immunology*; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods*; D007259:Infrared Rays; D051379:Mice; D012680:Sensitivity and Specificity
chemical_list: D001323:Autoantibodies; D024043:Collagen Type II