Schematic picture of the mBSA model of antigen induced arthritis, treatment regime and adoptive transfer experiment.

A) Balb/c (n = 69) mice were immunized subcutaneously against mBSA on day 0 (200 μg/mouse) and day 7 (100 μg/mouse). On day 21, arthritis was induced by a single intraarticular injection of mBSA (30 μg/mouse). Daily Flt3L (n = 33) or sham (n = 36) treatment was started 4 days (day -4) before the first immunization and continued throughout the experiment. Three independent experiments were preformed. B) For adoptive transfer experiment mice were treated with Flt3L (n = 25) or sham (21) for 14 days and immunized with mBSA on day 0 and day 7. At day 10, splenic CD11c+ (DCs) and T cells were isolated and transferred intravenously into naïve recipient mice (group1 n = 10; group2 n = 10 group3 n = 11 group4 n = 9). Mice were left for 11 days before arthritis induction by intraarticular injection of mBSA. Mice were sacrificed one week after arthritis induction. Two independent adoptive transfer experiments were preformed.