Adult stem cell

Adult stem cells are undifferentiated cells, found throughout the body after development, that multiply by cell division to replenish dying cells and regenerate damaged tissues. Also known as somatic stem cells, they can be found in children, as well as adults.

Characteristics

Adult stem cells have two important characteristics that distinguish them from other cells:

1. They are unspecialized cells capable of renewing themselves through cell division, sometimes after long periods of inactivity.
2. Under certain physiologic or experimental conditions, they can be induced to become tissue- or organ-specific cells with special functions.

Types

There are several known types of adult stem cells. These include:

1. Hematopoietic stem cells: Found in the bone marrow and blood, these cells give rise to all the types of blood cells: red blood cells, white blood cells, and platelets.
2. Mesenchymal stem cells: These cells are found in the bone marrow and can differentiate into a variety of cell types, including bone cells, cartilage cells, and fat cells.
3. Neural stem cells: Found in the brain, these cells can give rise to neurons and other cells of the nervous system.
4. Epithelial stem cells: These cells are found in the lining of the digestive tract and in the skin, and they give rise to the various types of epithelial cells.

Research and Clinical Use

Research on adult stem cells has generated a great deal of excitement. Scientists have found adult stem cells in more tissues than they once thought possible. This finding has led researchers and clinicians to ask whether adult stem cells could be used for transplants. In fact, adult hematopoietic, or blood-forming, stem cells from bone marrow have been used in transplants for more than 40 years.

See Also

• Stem cell
• Embryonic stem cell
• Induced pluripotent stem cell
• Stem cell treatments