How Are Stem Cells Cultivated for Stem Cell Research?
Stem cell research has opened up a world of possibilities for the treatment of formerly untreatable diseases, diseases in which the best hope is to slow the progress of the disease or make patients suffering from them a little more comfortable. The symptoms of these diseases, such as Alzheimer’s disease, COPD and degenerative joint diseases, result in part from damaged or diseased cells in certain organs or tissues. Stem cell research is devoted to finding ways to renew and repair those organs and tissues using undifferentiated cells that can become specialized once they reach the diseased organ or tissue.
In Simpler Terms
Stem cells have the remarkable potential to develop into the many different types of cells the body needs during early life and growth. They are, in a sense, template cells – basic body cells that haven’t had all the important blanks filled in yet. Many of the body’s tissues have “adult stem cells” – stem cells that are unique to that organ or tissue, but not specifically specialized. Think of these cells as a partially filled out template that still has room for more customizations. They reproduce without limit as long as the person or animal is still alive. When each stem cell splits, the new cell has the potential to remain a stem cell or to become a specialized cell, such as a muscle cell, a red blood cell or a brain cell.
In most cases, stem cells taken from the body can only produce the type of cells needed by the organ or tissue from which they were taken. Embryonic stem cells, on the other hand, are like completely blank templates, ready to be customized as any type of cell the body needs.
Where Do We Get Stem Cells for Stem Cell Research?
Scientists cultivate stem cells in dishes in the laboratory, using nutrients and growth factors to encourage growth. Most of the stem cell lines in current use have been cultivated on a feeder layer of animal cells, but they may not be safe for use in human stem cell therapy. Researchers have recently produced the first embryonic stem cell lines grown on human feeder cells. Another group reports that they have cultivated stem cells without using any feeder cells.
Embryonic stem cells are harvested from human embryos that are between 3 and 5 days old, when they contain 150-250 cells. The embryos used come from eggs that were fertilized at in vitro fertilization clinics but that were not implanted. The stem cells are donated with informed consent from donors.
Recent evidence suggests that adult stem cells may not be as limited as once thought. Bone marrow cells, for example, may be able to produce bone or heart tissue. Research continues on this line of stem cell research. In addition, some scientists are transforming adult stem cells into embryonic stem cells via gene manipulation. Again, only further research will tell whether stem cells altered in this way will cause adverse effects to people treated with them.