An astounding 80% of childhood cancer patients survive into adulthood, but nearly one half of boys who survive childhood cancer grow into men with either infertility or reduced fertility. This is because chemotherapy and radiation treatments often damage the cells which will eventually be responsible for producing sperm.
For these young boys, hope for assuring their future fertility lies in preservation of their testicular tissues before treatment. This preservation is common, but no clinical techniques for actually restoring fertility with these tissues have been developed – but now, University of Pittsburgh fertility researchers are seeking to validate one such technique for clinical use. Their paper describing the experiment was published earlier this year in Science.
Previously, success had been seen in grafting pre-pubertal testicular tissue from one species of mammal into that of another, which ended up producing both functional sperm and live offspring. Additionally, earlier work in nonhuman primates saw successful sperm production after immature testicular tissues were grafted back onto the individual from which they originated, an approach referred to as autologous grafting.
The Pittsburgh researchers bridged the gap between these two approaches by performing autologous grafting of immature testicular tissue in rhesus macaques, producing viable sperm as well as restoring testosterone production. Using assisted reproductive technology, the sperm was then used to produce the first primate offspring from a father with autologously grafted testes. She was named “Grady”, for graft-derived baby.
Grady’s birth story is one which will give hope to thousands of cancer survivors and likely many more to come. This accomplishment has made autologous grafting seem like a real possibility as a clinical therapy to return fertility to men who underwent cancer treatment as children in the near future.