Doctoral defence Artjom Stepanjuk: “Function of adhesion molecules and signalling pathways in human endometrial and embryonic models"

On April 25 at 12:15 Artjom Stepanjuk will defend his doctoral thesis "Function of adhesion molecules and signalling pathways in human endometrial and embryonic models“ (in Cell Biology).

Supervisors:
Professor Andres Salumets, University of Tartu
Associate Professor Emeritus Sulev Ingerpuu, University of Tartu
Associate Professor Maire Peters, University of Tartu

Opponent:
Associate Professor Damian Oscar Muzzio, University of Greifswald, Germany

Summary:
This doctoral thesis explores molecular mechanisms regulating female fertility. The research identifies novel molecular pathways involved in endometrial physiology and early embryoid body development using molecular biology techniques such as gene expression analysis, protein assays, in vitro models, and histological approaches. Understanding these mechanisms provides crucial insights into reproductive health.

Key findings reveal that mucins play a significant role in endometrial receptivity. Specifically, MUC20 expression increases in the mid-secretory endometrium, suggesting a regulatory interaction with the MET receptor, influencing epithelial cell adhesion and morphogenesis. Another critical discovery involves the role of ROCK2 kinase in decidualisation, a process essential for endometrial preparation before implantation. Elevated ROCK2 expression and activity drive changes in stromal cells through the ROCK/LIMK/cofilin pathway, promoting a secretory phenotype necessary for implantation.

Given ethical constraints on human embryo manipulation, alternative models such as embryoid bodies provide valuable insights. This study demonstrates that blocking integrin β1 disrupts embryoid body formation in vitro, underscoring its essential role in cell adhesion. Despite these contributions, the study has limitations, as direct cell-to-cell interactions remain hypothetical, and no clinical trials validate the findings. However, the research advances endometrial and implantation biology knowledge, paving the way for improved infertility diagnostics and therapies.

Future work should explore the molecular interactions between the decidualised endometrium and embryo in greater depth. Understanding epithelial-mesenchymal transitions in endometrial cells is crucial for grasping the complex dynamics of implantation. While many questions remain, this research highlights the intricate and fundamental nature of embryo implantation, a process vital for human reproduction.

The defence can be followed in Zoom (Meeting ID: 914 8117 3075, Passcode: 889363).