De novo design of a nanoregulator for the dynamic restoration of ovarian tissue in cryopreservation and transplantation.

The cryopreservation and transplantation of ovarian tissue underscore its paramount importance in safeguarding reproductive capacity and ameliorating reproductive disorders. However, challenges persist in ovarian tissue cryopreservation and transplantation (OTC-T), including the risk of tissue damage and dysfunction. Consequently, there has been a compelling exploration into the realm of nanoregulators to refine and enhance these procedures. This review embarks on a meticulous examination of the intricate anatomical structure of the ovary and its microenvironment, thereby establishing a robust groundwork for the development of nanomodulators. It systematically categorizes nanoregulators and delves deeply into their functions and mechanisms, meticulously tailored for optimizing ovarian tissue cryopreservation and transplantation. Furthermore, the review imparts valuable insights into the practical applications and obstacles encountered in clinical settings associated with OTC-T. Moreover, the review advocates for the utilization of microbially derived nanomodulators as a potent therapeutic intervention in ovarian tissue cryopreservation. The progression of these approaches holds the promise of seamlessly integrating nanoregulators into OTC-T practices, thereby heralding a new era of expansive applications and auspicious prospects in this pivotal domain.

Delaying Reproductive Aging by Ovarian Tissue Cryopreservation and Transplantation: Is it Prime Time?

Ovarian tissue cryopreservation and autotransplantation can restore ovarian endocrine function and fertility and recently were changed from experimental to fertility preservation procedures for medical indications by the American Society of Reproductive Medicine. Such advances have resulted in discussions around the utility of ovarian cryopreservation in healthy women to preserve fertility and delay menopause or as a hormone replacement approach. Such 'elective' use of ovarian tissue cryopreservation requires a risk-benefit assessment. Here, we review evidence for and against the utility of ovarian tissue harvesting in healthy women, scrutinize recent and needed advances to enhance the feasibility of such an approach, and provide practice and future research guidelines.

Prevention and treatment of iatrogenic premature ovarian insufficiency:interpretation of the first Chinese guideline on ovarian tissue cryopreservation and transplantation / 《全球健康杂志（英文）》

In recent years,with the rapid development of medical research,cancer diagnosis and treatment technology have significantly improved young cancer patient's survival rate.Anticancer therapy such as chemotherapy,radiother-apy,or hematopoietic stem cell transplantation can lead to premature ovarian insufficiency.The endocrine and reproductive function of the ovary is critical to women's physical and mental health.Ovarian tissue cryopreser-vation and transplantation can protect not only female fertility but also preserve ovarian endocrine function.This paper interprets the guidelines for ovarian tissue cryopreservation and transplantation issued by the Chinese Society of Gynecological Endocrinology affiliated to the International Society of Gynecological Endocrinology.The purpose of this guideline's interpretation is to promote more medical workers to understand the technology of ovarian tissue cryopreservation and transplantation,which can provide patients with more choices of fertility protection methods and improve their quality of life.

Follicle activation is a significant and immediate cause of follicle loss after ovarian tissue transplantation.

PURPOSE: Extensive follicle loss has been demonstrated in ovarian grafts post transplantation, reducing their productivity and lifespan. Several mechanisms for this loss have been proposed, and this study aims to clarify when and how the massive follicle loss associated with transplantation of ovarian tissue graft occurs. An understanding of the mechanisms of follicle loss will pinpoint potential new targets for optimization and improvement of this important fertility preservation technique. METHODS: Frozen-thawed marmoset (n = 15), bovine (n = 37), and human (n = 46) ovarian cortical tissue strips were transplanted subcutaneously into immunodeficient castrated male mice for 3 or 7 days. Histological (H&E, Masson's trichrome) analysis and immunostaining (Ki-67, GDF9, cleaved caspase-3) were conducted to assess transplantation-associated follicle dynamics, with untransplanted frozen-thawed tissue serving as a negative control. RESULTS: Evidence of extensive primordial follicle (PMF) activation and loss was observed already 3 days post transplantation in marmoset, bovine, and human tissue grafts, compared to frozen-thawed untransplanted controls (p < 0.001). No significant additional PMF loss was observed 7 days post transplantation. Recovered grafts of all species showed markedly higher rates of proliferative activity and progression from dormant to growing follicles (Ki-67 and GDF9 staining) as well as higher growing/primordial (GF/PMF) ratio (p < 0.02) and higher collagen levels compared with untransplanted controls. CONCLUSIONS: This multi-species study demonstrates that follicle activation plays an important role in transplantation-induced follicle loss, and that it occurs within a very short time frame after grafting. These results underline the need to prevent this activation at the time of transplantation in order to retain the maximal possible follicle reserve and extend graft lifespan.

Ovarian tissue cryopreservation and transplantation / 대한산부인과학회지

This review focuses on the current options for fertility preservation in patients with high risk of premature ovarian failure. Available cryopreservation options include embryo cryopreservation, oocyte cryopreservation, and ovarian tissue cryopreservation. Ovarian tissue cryopreservation and transplantation has been tried for some time in animals, but only recently successful pregnancy and livebirth in human has been reported. Options of developing follicles and restoring fertility after ovarian tissue cryopreservation are autotransplantation, xenotransplantation, and tissue culture. This review discusses the merits and faults of each option and future directions for developing and standardizing the ovarian tissue cryopreservation and transplantation procedure, systemically covering previously published data.