Project description:Vitrification is a method for long-term biological sample cryopreservation without causing intra- and extra-cellular ice formation. We recently established a novel closed vitrification system to cryopreserve mouse ovarian follicles. Using the 3D alginate hydrogel encapsulated in vitro follicle growth (eIVFG) method, we have demonstrated that compared to freshly-harvested follicles, vitrified follicles have normal follicle and oocyte reproductive outcomes. Our recent study further demonstrated the faithful preservation of molecular signatures of follicle-stimulating hormone (FSH)-stimulated follicle maturation in vitrified follicles. However, it is unknown whether ovulation, another crucial gonadotropin-dependent follicular event, and involved ovulatory gene regulatory pathways are well conserved in vitrified follicles. Fresh and vitrified follicles grown for 8 days by eIVFG were collected at 0, 1, 4 and 8-hour post human chorionic gonadotropin (hCG) treatment for the single-follicle RNA sequencing. Principal component analysis (PCA) and Pearson’s correlation analysis revealed that vitrified follicles have similar transcriptomic profiles to fresh follicles. Furthermore, the expression of several genes essential for ovulation were comparable between vitrified and fresh follicles. In summary, these results demonstrate that our closed vitrification system preserves follicular transcriptomic dynamics during ex vivo ovulation. Together with our previous findings that vitrification preserves FSH-stimulated follicle maturation, the integration of vitrification of immature follicles and eIVFG has a great potential to serve as an additional fertilization preservation approach for young cancer patients and endangerers species. Moreover, follicle vitrification enables a high-content ovarian follicle biobank, which can greatly improve the throughput of eIVFG for studying ovulation biology, anovulatory disease, toxicology, and novel contraceptive drug development targeting ovulation.
Project description:The rupture of ovarian follicles during ovulation is a crucial and intricate process essential for procreation, yet the molecular mechanisms behind this process are not fully understood. Here, we use high-resolution spatial transcriptomics to reveal the spatiotemporal regulation of cell-type-specific molecular programs driving follicle maturation and rupture during hormone-induced ovulation.
Project description:Ovulation refers to the process when the ovarian surface-facing wall of a preovulatory follicle ruptures and releases the cumulus oocyte complex (COC) into the oviduct or fallopian tube in response to hormonal cues. In parallel, the unruptured wall of the follicle within the ovary transitions to becoming a progesterone-producing corpus luteum. Ovulation is essential for fertilization and eventual pregnancy. Disruption of ovulation, whether purposefully through contraceptive intervention or idiopathically in cases of anovulatory infertility, has translational implications for human health. Importantly, key processes of ovulation, including follicle rupture and luteinization, are recapitulated in models of ex vivo ovulation despite the absence of an intact hypothalamic-pituitary-gonadal axis and intra-ovarian cues. In our study, we used an ex vivo ovulation model to identify functional and molecular differences between distinct regions of the follicle wall, which we refer to as the ruptured and unruptured sides. We observed that the unruptured side of the follicle wall exhibits hallmarks of luteinization after ovulation while the ruptured side exhibits signs of cell death. RNA-sequencing of these specific follicle regions revealed 2,099 differentially expressed genes between follicle sides without hCG exposure and 1,673 between follicle sides 12 hours post-hCG, which were further validated in vivo. We found enriched pathways that recapitulate known ovulation biology, including oxidative stress on the ruptured side and angiogenesis on the unruptured side. We also identified previously unappreciated pathways that may play an important role in ovulation, such as amino acid transport and Jag-Notch signaling on the ruptured side, as well as metal ion processing and IL-11 signaling on the unruptured side. Ultimately our studies demonstrate that our ex vivo model recapitulates known in vivo ovarian biology, identifies pathways that may be novel regulators of ovulation and luteinization, and may have future translational applications for the study of ovulatory disorders and the development of novel non-hormonal contraceptives.
Project description:Prospective, open labelled, multicenter trial to evaluate the feasibility of ex vivo culture 3D (chemogram obtaining) on biopsies in order to estimate the predictive value of this technique for treatment response in patients treated by two different chemotherapies (FOLFOX or FOLFIRI) for colorectal cancer.
Project description:The study aims to:
1. Achieve molecular imaging of EGFR in patients with colorectal neoplasia in vivo using confocal laser endomicroscopy.
2. Compare the results of in vivo EGFR-specific molecular imaging with CLE and ex vivo immunohistochemistry .