Decrease of thyroid antibodies during pregnancy.

The behavior of serum anti-thyroglobulin (Abs-Tg) and antimicrosomal antibodies (Abs-Mc) was examined during and after normal pregnancies. The antibodies titer decreases as pregnancy progresses; they cross the placenta and are present in the fetal serum. Infants' thyroid function is not affected by this transplacentar transfer.

Receptors for fluoresceinated human thyroglobulin in peripheral blood lymphocytes.

Fluoresceinated human native and desialylated thyroglobulin were incubated with peripheral blood lymphocytes. 1% of the lymphocytes, in twenty samples from normal human blood donors, showed a bright granular fluorescence where neither the number nor pattern of fluorescence differed from lymphocytes from the blood of thyroiditis patients. Fluoresceinated albumin and gamma-globulin did not bind to the lymphocytes, and a 500-fold excess of native non-fluoresceinated thyroglobulin inhibited the binding and pre-incubation with anti-IgM serum abolished it.

Immunological properties of Tg carbohydrates: enhancement of Tg immunoreaction by removal of sialic acid.

Immunoreaction of desialylated and native thyroglobulin was compared in sera of patients with anti-thyroglobulin antibodies by radioimmunoassay with 125I-labelled thyroglobulin. Two human thyroglobulins were iodinated both in vivo and by lactoperoxidase. After desialylation enhancement of immunoreaction was observed in several sera ranging from marginal to more than 100%.