Nude mouse interim host model for human parathyroid grafts. Part III. Mechanism of modification of allograft antigenicity.

The alterations of number and DR antigen expression of antigen presenting cells (APCs) in human PTG grafts during the interim hosting period were analyzed. The results were as follows: 1) In C-PTG grafts, the APC number was reduced obviously within 100 days in the interim host. In F-PTG and A-PTG grafts, the APC number was increased at 30 d of interim hosting, and then decreased gradually. 2) No obvious change in D-related (DR) antigen expression of individual APCs was seen in C-PTG and F-PTG grafts. In A-PTG grafts, DR antigen expression was increased at 30 d of interim hosting, but then dropped gradually and asynchronously.