Murine iPSCs were transduced with the retroviral construct MiDR, MiDR-FoxP3, or MiDR-TCR-FoxP3 and were co-cultured on the OP9-DL1/DL4/I-Ab cells. On day 7, the gene-transduced cells (3 × 106/mouse) were adoptively transferred into female C57BL/6 mice that were induced with AIA two weeks after the cell transfer. On the day following arthritis induction, the arthritis severity was monitored by measurement of the knee diameter. (A-C) Percent increase in knee diameter. Increase in knee diameter was calculated based on preinjection knee diameter for each mouse before injection on day 0. Arthritis score was evaluated by examining both knees in a blinded manner; each knee was assigned a score (0: no visible swelling or discoloration; 1: visible swelling with or without discoloration; 2: moderate swelling with discoloration; 3: severe swelling with discoloration). In each group, five mice were used, and data are representative of three independent experiments. Data are represented as the mean ± SD. (D) The mean scoring on day 7 for both knees from five mice. Data are represented as the mean ± SD from three independent experiments (** p< 0.01, *** p< 0.001, two-way ANOVA).