Speaker
Description
Studying the epigenetic landscape during the transition between pluripotency and the germline at multi-omics level enables to study the molecular basis of germ cell tumorigenesis and epigenetic inheritance. We recently developed and characterised a protocol to differentiate human pluripotent stem cells (hPSC) into Primordial Germ Cell-Like Cells (hPGCLC), and to go back again to pluripotency, deriving human Embryonic Germ Cell-Like Cells (hEGCLC) (Stucchi et al., biorXiv). This demonstrated the overlapping identities in terms of pluripotency and transcriptome between hPSC and hEGCLC and represents the first fully-defined and reproducible protocol to obtain hEGCLC.
To further characterise this cell type and its potency, we differentiated them into human cortical brain organoids (hCBO) and we are now investigating to which extent hEGCLC-derived CBO recapitulate human fetal cortex development, comparing them to hPSC-derived CBO. To this aim, we are characterizing this model at three different levels:
- At the transcriptomic level, by scRNAseq performed longitudinally at different timepoints (25, 50, 100, 200 and 300 days of differentiation);
- At the protein level, by 2D immunostaining for key neural markers;
- At the electrophysiological level, by Multi-Electrode Array (MEA).
The epigenetic dynamics that characterise hiPSC-to-hPGCLC-to-hEGCLC transition, recapitulate some of the key epigenetics changes occurring during the passage from one generation to the next. Combining this with the generation of CBOs from both hiPSC and hEGCLC represents a unique in vitro modelling strategy to study the inter-generational impact of environmental exposure on neurodevelopment.
By combining specific exposures, during hPGCLC differentiation, hiPSC-derived and hEGCLC-derived CBO differentiation, we are isolating the differential impact of environmental factors on parental and offspring neurodevelopmental outcomes, dissecting windows of vulnerability across parental prenatal and offspring prenatal periods.
Overall, this work will contribute to shed light on the impact of environmentally induced, epigenetically inherited changes on human neurodevelopment, providing scientific evidence to guide the reduction of adverse effects on present and future generations resulting from widespread environmental exposures.
