New models, new questions? Navigating the use of stem cell-based embryo models

A group of experts, including reNEW’s Associate Professor Nienke de Graeff, Professor Niels Geijsen and Professor Megan Munsie presented a White Paper on research, technological development and regulation of stem cell-based embryo models (SCBEMs). The White Paper, published in Human Reproduction, provides a framework to guide this emerging field.

The discovery that SCBEMs made from pluripotent stem cells can recapitulate some of the essential events of early human development raises unprecedented opportunities for researchers. These models can shine light on various developmental stages and embryo implantation and thereby have high potential to help address global health challenges such as infertility, pregnancy loss or congenital conditions. As the models become more sophisticated, they are also becoming more similar to human embryos created from fertilization. With these increasingly complex and relevant SCBEMs being developed, it is also increasingly important that ethical and legal questions around their use are addressed.

A group effort
Over 40 international experts worked together to fulfil this need. “This White Paper originates from a meeting of researchers at the Institut Pasteur in Paris in November 2024,” said De Graeff. “Since this meeting, the group expanded and worked towards a consensus that could be shared with the field.”

Importantly, the White Paper provides researchers and policy makers with an overview of SCBEMs. The authors describe characteristics, applications and advantages of the various models, but also reflect on relevant differences between SCBEMs and real embryos as this has strong impact on how they are used.

A guide for SCBEMs
Building on this overview, the experts subsequently elaborate on the legal and ethical considerations around SCBEMs and come up with several recommendations to support the sustainable and responsible use of SCBEMs.

“These recommendations entail amongst others the establishment of a distinct legal and ethical status for SCBEMs. This will help frame the distinction between embryo research and existing regulation and how the field should be governed going forward,” Munsie said.

Moving forward
The White Paper emphasizes that addressing the ethical and regulatory questions around SCBEMs requires continuous dialogue and adaptation to the latest developments in the field. Reflecting reNEW’s leading role in these efforts, De Graeff and Munsie have successfully secured further funding from the Lorentz Center for a workshop around this topic. The workshop will take place in Leiden later this year and brings together participants from various career stages, geographical regions and disciplines from across the life sciences, policy and bioethics to discuss the latest developments in SCBEM research.