Murine thyroiditis. 3. Influence of syngeneic and allogeneic thyroid antigen on induction of the disease.

Experimental autoimmune thyroiditis, characterized by thyroid antibodies (precipitating, haemagglutinating and complement fixing) and infiltration of the gland with mononuclear cells, was induced in inbred and randomly bred strains of mice, using thyroid extract from the same (syngeneic) or different (allogeneic) strains emulsified in sonicated Freund's complete adjuvant. The syngeneic antigen was much less efficacious than the allogeneic in inducing thyroid antibody and lesions. The subcutaneous route was more effective than intradermal immunization and pertussis vaccine decreased the incidence of the disease. Thyroid lesions and antibodies were found 9–14 days after immunization and were still present 3 months later. Differences, genetically determined, were observed in various inbred strains of mice in the degree of thyroid lesions as well as in the titre of thyroid antibody.