PhD Scientific Days 2026

Molecular Medicine 4.

Prediction of Implantation Success Using a Complex Animal Model for Embryo-Endometrial Crosstalk

Name of the presenter

Nagy, Bence

Institute/workplace of the presenter

Institute of Genetics, Cell- and Immunbiology

Authors

Bence Nagy¹, Zoltán Bognár², Timea Judit Csabai², Gergely Berta², Nóra Fekete¹, Éva Pállinger¹
1: Institute of Genetics, Cell- and Immunobiology, Semmelweis University, Budapest, Hungary
2: Department of Medical Biology, Medical School, University of Pécs, Pécs, Hungary

Text of the abstract

Introduction
The efficacy of assisted reproductive technologies is significantly affected by the timing of embryo transfer. However, there is no widely accepted biomarker that can identify the window of implantation. Deviating by 12 hours from the optimal transfer time decreases the likelihood of successful implantation by around 45%.
Aims
This study aims to conduct a comprehensive molecular analysis of embryo-endometrium communication, focusing on soluble mediators derived from the endometrium, as well as extracellular vesicle (EV) patterns and the implantation-associated transcriptome.
Methods
A murine animal model was used to characterise the pre-receptive and receptive phases of the endometrium. Samples were collected at 2.5 and 4.5 days post-coitum (dpc). Serum progesterone levels and endometrial progesterone receptor expression were assessed. Uterine lavage was used to analyse cytokines and extracellular vesicles (EVs). The expression levels of implantation-associated adhesion molecules were determined by RT-PCR.
Results
The investigated analytes can differentiate between the pre-receptive and receptive phases of the endometrium. At 2.5 dpc, significantly higher amounts of EVs expressing CD24, CD29, CD326, CD44, CD49b, CD49a and CD66 could be determined. In contrast, at 4.5 dpc, the concentrations of proinflammatory IL-6, IFN-γ and MCP-1 significantly decreased, while CD44, CD81 and CD29 were significantly upregulated.
Conclusion
These findings demonstrate clear molecular differences between receptive and non-receptive phases, suggesting that uterine lavage analysis may provide a basis for identifying noninvasive biomarkers of implantation in humans.
Funding
This work was supported by the National Laboratory on Human Reproduction. Project no. RRF-2.3.1-21-2022-00012, titled "National Laboratory on Human Reproduction," was conducted with backing from the European Union's Recovery and Resilience Facility under the Széchenyi Plan Plus Program. The project received funding from the HUN-REN Hungarian Research Network and STIA_2024 (19279/PMKP/2025). Project no. TKP-2021-EGA-10 was executed with support from the National Research, Development, and Innovation Fund of Hungary, which was funded under the TKP-2021-EGA program. The PTE Medical School (Szolcsányi Foundation) supported the work.