Expression of proteins for various cytokines in the synovial membrane of rats with AIA. Expression of protein was assessed before the induction of antigen-induced arthritis (AIA) (day 0) or afterwards (at 6 hours and on days 1, 3, and 6). Data were originally expressed as ng/mg total protein and then related to values of day 0 (fold change; peak values in ng/mg total protein are indicated for 6 hours). Values are means; vertical bars indicate the standard error of the mean (n = 5 to 6 rats for each time point). *P ≤ 0.05 in comparison with day 0; +P ≤ in comparison with the preceding date.