Previous to initiation of this study, it had not been shown that cryopreserved endothelial cells survive in vivo following penetrating keratoplasty in primates, though such a survival is suggested by in vitro studies and favorable clinical results. In this study, eight eyes of five monkeys received full-thickness corneal grafts using cryopreserved monkey donor tissue of sex opposite to that of the recipient. The eyes were removed at varying intervals from 5 to 22 weeks postoperatively, and sex chromatin patterns of the corneal endothelial cells were studied. Definite survival of cryopreserved donor endothelial cells or their progeny was observed in all of the eight eyes.
Bourne WM. In Vivo Survival of Cryopreserved Endothelial Cells in Primates. Arch Ophthalmol. 1974;92(2):146-148. doi:10.1001/archopht.1974.01010010152015