Type-7: Fertility Protection in Cancer: Recovery of Whole Ovaries enabled by Next Gen Perfusion, Cryoprotection, and Nanowarming

There is a need and opportunity to improve the lives of the many tens of thousands of young cancer survivors annually, who face lifelong hormone imbalance and infertility due to cancer treatments that damage their reproductive organs. Ovary banking and autotransplantation has been proposed as a method to avoid irreversible damage, yet no clinical method exists to keep whole ovaries viable until re-implantation. Using carefully optimized protocols and effective cryoprotective agents, our team and others have successfully cryopreserved multiple tissues in an ice-free vitreous “glassy” or “amorphous” state, allowing for indefinite storage. Unfortunately, these advances in ice- free preservation had not been matched by similar advances to prevent damage from ice growth and/or fracturing during rewarming preventing viable banking. Recently, however, our Co-PI, Dr Bischof, demonstrated a scalable and biocompatible nanowarming technology using radiofrequency (RF)-excited iron oxide nanoparticles (IONPs) for ice and fracture avoidance that we demonstrated proof of concept of for vascularized whole ovaries during phase 1 and after. This program works to preserve fertility and hormone function for cancer survivors by developing nanowarming enabled cryobanking of whole human ovaries and ovarian tissue strips, for re-plantation following damaging chemo and radiation therapies. Combining nanowarming with recent advances in machine perfusion, optimized loading/unloading procedures, next generation non-toxic cryopreservation solutions, computational modeling, and powerful tissue imaging (e.g. cryomacroscopy, uCT, SWIFT-MRI), our approach leverages a convergence of state-of-the-art technologies to develop a comprehensive preservation protocol for reproductive organ protection that will maximize tissue viability. Building on the success in the feasibility phase, this project will deliver two primary products: (i) improved vitrification and re-warming strategy (compared to current gold-standard slow freezing) for preservation and banking of ovarian tissues for transplantation, (ii) comprehensive tools (including multi-thermic perfusion system), and protocol for recovery and successful banking and nanowarming of whole human ovaries to ultimately support whole ovary re-plantation (not possible with current methods). In addition, this project provides tools, equipment, solutions and protocols with highly- translatable technology toward banking of whole vital organs, and other vascular grafts, addressing widespread needs for breakthroughs in preservation – from improved cell and biospecimen preservation to whole organ banking. The project’s initial focus is to optimize preservation of human ovarian tissue strips followed by development of a comprehensive banking strategy for whole human ovaries. We will validate early in vitro success in two transplant models: (1) xenotransplantation of human ovarian tissue strips in nude mice, and (2) minimally invasive autotransplantation of nonhuman primate ovarian tissue strips from whole cryopreserved ovaries. Based on the results from Phase 1 with whole ovaries, and subsequent studies since then, we believe that we are close to a successful protocol for indefinite preservation of ovaries. Success of these novel approaches individually or in combination will likely enable further breakthroughs in oncofertility, biopreservation research, and clinical practice.