Molecular distribution of preformed thyroglobulin immune complexes.

Thyroglobulin anti-thyroglobulin immune complexes with human antibodies from four patient sera were performed in a wide range of antigen: antibody ratios and run in 5%-40% sucrose gradients. The fractionation showed simple distributions of thyroglobulin molecules in immune complexes, especially in far antigen and far antibody excess. A computer simulation analysis which utilized the experimental presumptions and assumed an association constant in the order of 10(9), showed a large degree of similarity to the experimental results. Thus, a thermodynamically simple explanation of immune complex formation did not contradict the experimental thyroglobulin anti-thyroglobulin complex formation.