What Are Fetal Stem Cells?

Stem cells are cells that can potentially reproduce into any kind of cell. Stem cells can be harvested from developing fetuses that have been created in vitro or from aborted embryos less than 5 days old. There are also stem cells in adult tissue, but this type of stem cell is limited as to the type of cell it can produce. Stem cells are capable of maturing into any kind of cell, or of regenerating damaged cells; therefore, stem cells can be used to treat a variety of degenerative illnesses such as Parkinson's disease, Alzheimer's disease and arthritis, as well as injuries and disabilities from burns, spinal cord damage and traumatic brain injuries.

Pluripotent Cells

• The stem cells harvested from fetuses are called pluripotent. This means they have the potential to develop into any type of human cell. Pluripotent stem cells come from the inner cells of a blastocyst (a 4 to 5 day old embryo), though scientists can also create stem cells from tissue taken from older embryos. In theory, these stem cells can divide indefinitely, as long as the organism is alive. When a stem cell divides, it creates two daughter cells which can become either stem cells or another type of cell, like blood, skin or liver. Pluripotent cells are cultured in a laboratory to produce more lines of pluripotent cells.

Hematopoietic Cells

• Hematopoietic cells are fetal stem cells harvested from the blood in the umbilical cord after a baby is born. These cells are most likely to produce blood cells, so their medical use is limited. However, they can be quite effective in treating blood diseases like leukemia and many types of anemia. Parents of babies with these diseases, or who have genetic predispositions to these diseases, can have the umbilical cord blood frozen in case the cells are needed in the future.

Multipotent Cells

• Stem cells in adult tissue are called multipotent. This means they have the ability to regenerate new cells, but the type of cell they can produce is limited. There are very few stem cells in an adult body, and their capacity for regeneration is not as great as that of embryonic stem cells. Multipotent stem cells are not constantly dividing. Instead, they wait until there is a need to produce more cells, either from injury or illness, and begin regenerating tissue. Multipotent cells have been used for over 40 years in bone marrow transplants and for treating leukemia, and new uses are currently being researched.

Medical Uses

• Once a fetal stem cell has been harvested, it has the potential to live indefinitely in the laboratory. Scientists can culture more stem cells to be frozen for future use or shared with other scientists. Research for stem cell therapy is ongoing, but scientists believe they have the potential to create human organs from stem cells, as well as treat burns, paralysis from injuries and degenerative diseases of the brain, nerves and muscles.

Ethical Debate

• Until now, most stem cell research has been conducted on rats because of the ongoing ethical debate of harvesting cells from human embryos and fetuses. However, existing human stem cell lines were all derived from embryos created in vitro at fertility clinics that otherwise would have been thrown away. In 2009, President Barack Obama signed an executive order restoring federal funding for stem cell research.