Chips used for biomarker profiling on the IMPACT platform. (a) Images of an IMPACT synovial antigen chip 1 probed with sera derived from a patient with RA. Fluoresence was captured with a charge-coupled device camera and quantified by software analysis. The images are false color representations of the fluorescence signals detected. Blue represents low, green intermediate, yellow high, and white the highest levels of fluorescence. The upper chip image is enhanced in the lower image by conversion of the lowest 5% of signals to black and the top 5% of signals to white, with the color scale adjusted accordingly. The rheumatoid arthritis sample analyzed exhibits very high levels of autoantibody reactivity to fibrinogen A (616-635) (Cit 621, 627, 630), vimentin (58-77) (Cit 64, 69, 71), and profilaggrin (293-310) (Cit 301, 302)), and low levels of antibody reactivity to fibrinogen A (31-50) (Cit 35, 38, 42), biglycan (247-266), and histone 2B/e (1-20). (b) List of chips and their components.