Previously, we reported that administration of the pathogenic antigen, GPI325‐339, in combination with FTY720 efficiently suppressed the progression of GPI325‐339‐induced arthritis symptoms by induction of: (1) T cell apoptosis; (2) inhibitory molecule (CTLA‐4 and programmed death‐1) expressing non‐Treg cells; and (3) the expansion of Treg cells in inguinal LNs 14. The gene discussed is CTLA4; the disease is arthritic joint disease.