Transplantation of human endocrine tissues to nude mice: a suitable in vivo model for the study of pathomechanisms involved in autoimmune thyroid diseases.

After transplantation of human tissue to nu/nu mice the human lymphocytes disappear. In this context, interestingly, the DR-expression is not detectable anymore after transplantation of the tissues from patients with autoimmune thyrotoxicosis and cancer. Neopterin release was only demonstrable when T-lymphocytes from patients with autoimmune thyrotoxicosis or PHA-stimulated lymphocytes were added, independently of the presence of DR-expression in the used culture tissues. These results seem to exclude a functional role of DR-expression as a trigger mechanism of autoimmunity. It is supposed that DR-priming on epithelial cells is mediated by kinine production of activated T-lymphocytes or macrophages.