Early evaluation of survival of the transplanted ovaries through ultrasound molecular imaging via targeted nanobubbles.

Ovarian survival after transplantation is key to determining the success and efficacy of ovarian tissue cryopreservation and transplantation (OTCP). However, non-invasive monitoring of ovarian survival in the early stages of ovarian transplantation remains a great challenge. Anti-Müllerian hormone (AMH) is a survival factor that can promote the growth of follicles and has been recognized as an ovarian tissue-specific marker. In this study, we developed AMH-targeted nanobubbles (NB) by integrating an AMH antibody onto the surface of NBs. The resulting NB exhibited a high affinity for ovarian granulosa cells in vitro and a significantly enhanced ultrasound signal in transplanted ovaries relative to the non-targeted NBs. Notably, the difference in enhanced ultrasonic signals became more significant with the increase in time after transplantation from 3 to 10 days, indicating a gradually enhanced AMH expression along with the increase in transplant time. These results were further confirmed by immunohistochemical staining and western immunoblotting analyses. In conclusion, our study offers a promising non-invasive tool to monitor ovarian survival in the early stages following transplantation.