7-6

Figure 7-6 Some of the proposed mechanisms which could produce thyroid damage in AITD. Emperipolesis is the movement of lymphocytes and macrophages between epithelial cells and occurs in many organs such as gut, bronchus, and thyroid. The existence of interepithelial cells with immunoreactive potential is obviously relevant to an understanding of how autoantigens at the luminal surface of the thyroid cells may be exposed to allow recognition. (From Weetman AP, McGregor AM. Endocrine Rev 5: 309-355, 1984 ).