Restoration of autoimmune thyroiditis in bursectomized-irradiated OS chickens by bursa cells.

OS chickens were subjected to bursectomy, thymectomy, bursectomy-X-irradiation and bursectomy-X-irradiation followed by restoration with autologous bursa cells. The influence on the spontaneously occurring thyroiditis was studied. Less pronounced thyroiditis and thyroglobulin antibody formation was found in the bursectomized and bursectomized-irradiated but not in the thymectomized chickens. Bursectomized-irradiated chickens which had been reconstituted with autologous bursa cell suspensions showed total restoration of the thyroiditis. No restoration of thyroglobulin antibody forming capacity and only partial restoration of immunoglobulin level was observed. The results suggest a dual function of the bursa with regard to thyroid autoimmunity in OS chickens, one humoral and possibly hormonal, which is essential for thyroglobulin antibody formation and one cellular which is necessary for the development of the inflammatory lesions in the thyroid gland.