Fig. 1

Indirect IF on unfixed thyroid tissue. a Pattern produced by a normal serum: the cytoplasm of thyrocites and the thyroglobulin inside the follicles are negative, the fluorescence is concentrated in the connective tissue between the thyroid follicles (arrow). b Pattern produced by a serum of a patient with high titers of TMA and TgAbs: the cytoplasm of the thyrocites is diffusely and intensively stained and the substance inside the follicles is also intensively stained. c Pattern produced by a serum of a patient with high titers of TMA: the cytoplasm of the thyrocites is diffusely and intensively stained and the substance inside the follicles is negative. d Pattern produced by a serum of a patient with low titers of TMA: a weak positivity is present in the cytoplasm of thyrocites with reaction in the apical rim of thyrocites where the microsomal antigen is concentrated (arrow). e Pattern produced by a serum of a patient with high titers of mitochondria Abs: the serum shows a granular pattern of cytoplasm of thyrocites and the reaction is concentrated in scattered cells rich in mitochondria (see arrow). f Pattern produced by a serum of a patient with high titers of anti-nuclear Abs: the reaction is positive on the nuclei of thyrocites