Expression of AR in donor and grafted tissue. A, Three-month-old donor tissue. B, Six-month-old donor tissue. C, Graft from 3-month-old donor recovered from untreated mouse. D, Graft from 6-month-old donor recovered from untreated mouse. E, Graft from 3-month-old donor recovered from gonadotropin-treated mouse. F, Graft from 6-month-old donor recovered from gonadotropin-treated mouse. AR expression was apparent in Leydig cells in donor tissue and grafts recovered from untreated mice (A-D, arrowheads) whereas AR was expressed strongly in Sertoli cells in grafts recovered from treated mice (E and F, arrows). Bar, 50 μm.