Qa-2 siRNA deteriorated BD symptoms. For each mouse, 500 nmol each of control siRNA or Qa-2 siRNA in 200 ml of 5% glucose solution was intraperitoneally injected four times with three day intervals, and the symptoms were photographed (A) and the severity score was analyzed (B) two days after the last injection. The severity was lower in Qa-2 siRNA injected BD mice when compared to control siRNA injected BD mice, although this change was not significant. The disease score was estimated according to the Patients Index Score, Behcet's disease current activity form 2006, ICBD. The symptoms of BD mice deteriorated after treatment with Qa-2 siRNA. Deterioration occurred in three of six BD mice (A). When treated with control siRNA, the deterioration occurred in one of six mice, while no change was observed in any of the mice injected with 5% glucose.