Table 1.

Shared characteristics between thyroid and stomach.

Embryological origin	Primitive gut for both thyroid and stomach
Cell features	Presence of cells polarity Cells characterized by apical microvilli
Biochemical features	Presence of Na+/I− symporter (sodium-iodide symporter) Presence of peroxidase isoenzymes (TPO and GPO)
Function	Ability to concentrate iodine Presence of antioxidative activities Secretion of mucinous glycoproteins: thyroglobulin and mucine
Pathogenesis	Cellular immune involvement Similarity of autoaggressive processes Mechanisms of cellular damage Expression of autoantigens and related cross-reacting autoantibodies
Pathology	Clinically related autoimmune disorders Peculiar associative clinical features