Studies on Organ Specificity

Abstract

Summary The interactions between human sera and human and monkey thyroid antigens were studied by the fluorescent antibody method, complement fixation, and tanned cell hemagglutination. Three types of antibodies which stain human thyroids were demonstrated in human sera by the fluorescent antibody method. The antigens are characterized by staining of: a) thyroid colloid, b) cytoplasm of thyroid epithelium, and c) thyroid nuclei. Antibodies to thyroid colloid and to the cytoplasm of thyroid epithelium frequently occur together. Some sera appear to contain only antibodies to the cytoplasm of the thyroid epithelium. Antibodies to thyroid colloid and to the cytoplasm of thyroid epithelium were further differentiated by: a) differences in the chemical stability of the two antigens, b) selective removal of antibodies which stain thyroid colloid by adsorption with thyroglobulin. Sera which stained the cytoplasm of thyroid epithelial cells by the fluorescent antibody method also fixed complement with human thyroid microsome, to a lesser extent with human thyroid mitochondrial fraction and not at all with the nuclear fraction. Adsorption of sera, even with well washed microsomes, removed both the cell and the colloid staining antibodies. Immunofluorescent staining of the cytoplasm of thyroid epithelium occurred with the patient's own thyroid sections in three cases thus confirming the autoantibody nature of the reaction. All sera which stained thyroid colloid by the fluorescent antibody method also gave strong hemagglutination reactions. The converse was not always true. Hemagglutination occurred with the patient's own thyroid extracts in two cases thus confirming the autoantibody nature of this type of reaction. One of 17 sera studied stained all three thyroid consituents, the colloid, the cytoplasm of the epithelial cells, and the thyroid nuclei. Nuclear staining and colloid staining antibodies were removed by selective adsorption. Sera containing nuclear antibodies (mostly from patients with lupus erythematosus) stained no other component of thryoid sections but stained nuclei of all organs. Pathologic diagnosis and serologic findings were compared in 46 thyroidectomized patients. Thyroglobulin autoantibodies occurred in all chronic nonspecific thyroiditis cases. No other generalization could be made.