Immune responses to thyroglobulin in experimental allergic thyroiditis.

Guinea-pigs immunized with homologous thyroglobulin in complete Freund's adjuvant were observed for lesions in the thyroid gland, and for development of specific delayed type skin hypersensitivity. Their blood leucocytes were examined for specific sensitivity in vitro by determining the inhibition of migration in the presence of thyroglobulin. Serum was tested for humoral antibodies by the passive haemagglutination technique. There was a significant correlation between the development of thyroiditis and the intensity of the skin reactions. No relationship was observed between the presence of thyroiditis and leucocyte sensitivity nor between thyroiditis and circulating antibodies. On the other hand serum antibody titres were correlated to the degree of leucocyte sensitivity. Thyroglobulin inhibited the migration of cells from normal animals in the presence of plasma from thyroglobulin-sensitized animals. The activity of sensitized plasma disappeared when diluted 1:10 in normal plasma irrespective of the serum antibody titre. Guinea-pigs immunized with thyroglobulin or kidney antigen in complete Freund's adjuvant and tested for skin or leucocyte hypersensitivity showed specific but no cross reactivity to the two preparations.