Determination of thyroid antimicrosomal antibodies by solid-phase radioimmunoassay

Thyroid antimicrosomal antibodies have been detected in patient's serum by immunofluorescence and hemagglutination techniques as well as by radioimmunoassay. The aim was to introduce the solid-phase radioimmunoassay for thyroid antimicrosomal antibodies determination. The microsomal fraction was adsorbed on the walls of polystyrene tubes. In the next stage patient's serum was added. The retention of antibodies bound to microsomes on the tube walls was detected by adding 125I-protein A. The occurrence of antimicrosomal antibodies in the group of patients with Graves' disease was 88%; in case of myxedema autoantibodies were found in 70%. In patients with chronic thyroiditis antimicrosomal antibodies were present in 90% and in the group of non-toxic goiter the incidence was 25%. In the control group antimicrosomal antibodies were found in 8%. The solid-phase radioimmunoassay for thyroid antimicrosomal antibody determination proved to be a useful, sensitive and reproducible method for clinical studies. (author)