Effects of time and immunization on the animal model of Graves' disease

Objective: To investigate the effects of time and immunization frequency of administration of Ad-TSHR289 on the development of a Graves' disease (GD) animal model. Methods: BALB/c mice were injected with Ad-TSHR289 or Ad-lacz twice (5 week) or thrice (10 week) at three-weekly intervals. Blood and thyroid glands were obtained 2 weeks or 4 weeks after injection. Total thyroxine (TT4) and thyrotropin receptor autoantibody (TRAb) levels were measured by radioimmunoassay (RIA). Results: TRAb significantly increased in all the mice injected with Ad-TSHR289 compared with the controls. The incidence of GD was 56% (9/16) in 5-week model group and 75% (9/12) in 10-week model group. The consistency between serum TT4 level and histological changes of the thyroid was 50% in 5-week model group and 100% in 10-week model group, respectively. Conclusion: Ten-week intervention is more effective than 5-week one in inducing a GD animal model. Intervention time and immunization frequency are two important factors affecting the development of a GD animal model induced by Ad-TSHR289.