EXORep · EXOsomes as a new strategy in Assisted Reproductive Technologies: tracing maternal nanomessengers to improve pregnancy outcomes

EXOsomes as a new strategy in Assisted Reproductive Technologies: tracing maternal nanomessengers to improve pregnancy outcomes

Assisted reproductive technologies (ART) have come a long way in the last 30 years both in animals and humans and are well established in the clinical practice. In vitro embryo production (IVP) is performed and transfer of embryos at the blastocyst stage to achieve successful pregnancy. However, even after improvements of the technology, the quality of IVP embryos is still lower compared to the in vivo ones. The lack of embryo-maternal interactions and the maternal signals in the in vitro embryo culture conditions have been postulated as the main reason for the lower embryo quality. Recently, a new mechanism has been proposed pointing at the potential role of extracellular vesicles (EVs) as important mediators of the early embryo-maternal crosstalk. EVs are present in various biofluids and carry different biomolecules such as proteins, nucleic acids (different types of RNAs and DNA), lipids, and metabolites that provide a snapshot of the parental cells at the time of secretion but also transfer specific signaling and regulatory molecules. For example, the EVs’ molecular cargo has been used as biomarkers for diagnosis and prognosis of cancer and other diseases in recent years. Therefore, in the present project, we hypothesized that the oviductal environment as the first site of interactions between the mother and the early embryo, and particularly the oviductal EVs (oEVs) could be important for optimal embryo development. The main objective of this project was to investigate the potentials of oEVs to improve IVP conditions to achieve better pregnancy rates in dairy cattle, but also in humans. The bovine model was used because of its similarities to human during early embryo development. To reach this overall objective, the following specific objectives were addressed: Objective 1. Analysis of oEVs in response to the embryo and its different stages of development (before and after genome activation). Objective 2. Analysis of oEVs in response to good or poor-quality embryos. Objective 3. Identification of crucial molecules contained in oEVs involved in the support of embryo development. Objective 4. Evaluation of the potential ability of oEVs’ to improve ART outcomes.

Data: CORDIS, © European Union