Expanded Potential Stem Cells Established in Pigs and Humans

A new approach has enabled researchers to create Expanded Potential Stem Cells (EPSCs) of both pig and human cells. These stem cells have the features of the very first cells in the developing embryo and can develop into any type of cell. The new research, published today in Nature Cell Biology, offers incredible potential for studying human development and regenerative medicine.

Stem cells have the ability to develop into other cell types, and existing stem cell lines are already extremely useful for research into development, disease, and treatments. However, currently available stem cell lines have limitations, and until now, it has also not been possible to create embryonic stem cells from pigs.

“Scientists have been attempting to derive porcine embryonic stem cells for decades without much success,” says senior author Pentao Liu of HKUMed. “With our Expanded Potential Stem Cell technology, we have now successfully derived and characterized stem cells from porcine preimplantation embryos. We have also established similar human stem cells.”

EPSCs come from culturing cells from the earliest stage of development, when the fertilized egg has only divided into 4 or 8 cells and the cells retain some totipotency—the ability to produce all cell types.

“These EPSC stem cells possess developmental potency that is not generally seen in conventional embryonic or induced pluripotent stem cells,” explains first author Xuefei Gao, also of HKUMed. “They have the potential to produce all embryonic and extra-embryonic cell lines—including those in the placenta and yolk sac, turning back the development clock to the very earliest cell type. These cells will enable researchers to study early embryonic development, miscarriage, and developmental disorders.”

The first EPSCs were created in 2017 when the group targeted key molecular pathways during very early development in mice. At these early developmental stages, mammalian species are very similar and the cells are like a blank sheet of paper. This study has shown that it is possible to use the same approach to create both human and pig EPSCs.

“Our porcine EPSCs isolated from pig embryos are the first well-characterized pig cell lines worldwide,” says coauthor Monika Nowak-Imialek of the Friedrich Loeffler Institute. “EPSC’s great potential to develop into any type of cell provides important implications for developmental biology, regenerative medicine, organ transplantation, disease modeling, and screening for drugs.”