An Insulin-like Thymic Factor: A Preliminary Report

Previous studies have indicated that AKR strain mice develop hypoglycemia and thymic enlargement in association with spontaneous lymphatic leukemia. Histologic, biologic and immunologic studies of the thymus in the AKR mouse and other vertebrate species have shown that the reticular cells and Hassal's bodies secrete or store an insulin-like material. These data coupled with the embryological origin of the thymus suggest that it functions as an endocrine organ. The implications of these findings are discussed.