PhD student University of Sheffield, England, United Kingdom
Abstract: For human pluripotent stem cell (hPSC)-based therapies to enter routine clinical use, ensuring their efficacy and safety is critical. A significant challenge lies in the recurrent chromosomal abnormalities frequently acquired during hPSC in vitro expansion. These abnormalities lead to altered cell behaviours such as enhanced proliferation or reduced differentiation potential, raising concerns for hPSC usability in the clinic. Understanding the mechanisms driving these abnormal variants is essential for eliminating them from cultures. One proposed mechanism for variant emergence is mitotic error. hPSCs are known to exhibit poor mitotic fidelity compared to somatic cells or differentiated counterparts, likely due to an impaired mitotic checkpoint. However, the mechanisms of aneuploidy propagation and consequences of these in hPSCs, are still poorly understood. In this project, we explore chromosome mis-segregation in pluripotent versus isogenic differentiated cells. Using chemical and genetic manipulation techniques combined with timelapse microscopy, we study the acute and long-term cellular responses to aneuploidy induction. Additionally, using aforementioned techniques, we successfully generate a panel of novel aneuploid hPSC lines, and utilise these to study chromosome-specific effects of aneuploidy on cell fate and differentiation. This work provides critical insights into the origins and implications of chromosomal abnormalities in hPSCs, advancing our understanding of how to mitigate these risks for safe and effective clinical applications.
