The testis and tissue transplantation: historical aspects.

Transplantation experiments involving the testis have been performed since the days of John Hunter, who transplanted a testis into the belly of a hen. The first person to use the testis as a site of transplantation appears to have been Sand, who found in 1919 that an ovary transplanted into the substance of the testis developed follicles. By 1970, there was considerable evidence that the testis under some circumstances was a relatively favorable site for graft survival. However, much of the evidence was equivocal, and the immunological privilege was by no means complete.