Cells, Fetal

ON THE BASIS of National Institutes of Health guidelines, a human fetal stem cell is defined as a cell derived from either a human embryo or a fetus harvested after abortion, whether intentional or incidental. However, this définition fails to highlight the primary difference between embryonic and fetal stem cells. This difference is a question of degree of multipotency. Where the embryonic stem cell is considered to be pluripotent—able to differentiate into any cell type in the human body—most fetal cells are believed to only be multipotent to a limited degree. To put it into layperson's terms, an embryonic stem cell is like the seed of a plant, whereas a fetal cell is a sprout. The seed could grow into any plant type, but the ...