"How Far Have We Reached with Regards to Our Endeavours in Testicular Tissue Transplantation Along with in Vitro Spermatogenesis After Success in Animals - A Systematic Review"

After reviewing the role of very small stem cells role in both male and female fertility with regards to oncofertility, here we tried to explore what can be done with regards to more problems in relation to male infertility say cases of azoospermia, in cases of transgender males, especially oncofertility where prepubertal boys are concerned. Here we have reviewed work done on testicular tissue preservation and transplantation in both adult and prepubertal boys, more so research that has been successfully conducted in animals and whatever is the latest research on humanbeings. We conducted a systematic review utilizing pubmed search engine, google scholar, embase, Cochrane library, web of science and looked for MeSH terms like Spermatogonial Stem Cells; cryopreservation; males undergoing therapy for malignancies both prepubertal and adults; transgender females; kline felter syndrome; azoospermia with maturation arrest; testicular tissue cryopreservation; testicular tissue immature; mature testicular tissue; autologous transplantation; xenografting; various animal species like nonhuman primate studies; rodent; from 1990-2020 till date. We found a total of 1250 articles out of which we selected 100 articles for this review. No meta-analysis was conducted. Once safety has been achieved after animal studies time has come for this to reach the clinical scenario. The best that has been achieved in humans is cryopreservation of immature testicular tissue in prepubertal boys although till now no successful sperm production in humans has been reported. We are waiting for the day when even males having round spermatids might be utilized and how we can utilize SSC’s, VSEL’s present in niche around the sertoli cells as reviewed earlier and hopefully that day is not far.

Keywords: Spermatogonial Stem Cells; cryopreservation; transgender females; immature testicular tissue cryopreservation; Cell Suspension; Xenografting; Aoutologous transplantation.