CHARACTERIZATION OF ANTI-THYROGLOBULIN FACTORS IN HUMAN SERUM

Abstract

Sera from 118 patients with a variety of diseases were examined for anti-thyroglobulin activity by the agglutination of red blood cells treated with tannic acid and coated with human thyroglobulin. Anti-thyroglobulin activity was found most commonly but not exclusively in patients with clinical evidence of chronic thyroiditis. The serum factors responsible for anti-thyroglobulin activity were characterized in detail in seven sera, including four from patients with chronic thyroiditis. Anti-thyroglobulin activity was found only in the gamma-globulin fraction of the serum proteins. The activity was found to be a single component with the sedimentation characteristics of 6.6S gamma-globulins in five sera. In two sera, however, anti-thyroglobulin activity was found in two components with the sedimentation characteristics of 6.6S and 18S gamma-globulins, respectively. The 6.6S and 18S types of anti-thyroglobulin activity could be separated and their recognition facilitated by anion-exchange cellulose chromatography. Chromatographic sepa-ration, in addition, made possible quantitative measurement of each of the two types of activity. The possible role of antigen and host factors in determining the type of antibody response was briefly considered. No common clinical feature in the two patients producing 18S anti-thyro-globulin antibodies could be found which would distinguish these two patients from the 6.6S antibody-producing patients.