August 25, 2012
What Are Stem Cells?
What are stem cells?
Stem cells are unique cells with the great ability to become various types of cells. Stem cells can continue to divide for extended periods of time, but specifically, here are 3 unique properties of stem cells. First of all, most cells, such as skin cells, cannot replicate themselves after time. Stem cells are different. Stem cells are self-sustaining by replicating themselves for a much longer period of time. They are present both during embryonic development as embryonic stem cells, and in the adult body as adult stem cells.
Secondly, stem cells are non-specialized. Specialized cells have specific capabilities that allow them to perform certain tasks. For example, a red blood cell contains hemoglobin that allows it to carry oxygen. Stem cells have non-specialized capability and do not have tissue- specific structures to perform specialized functions.
Finally, stem cells can give rise to specialized cells. Stem cells go through a process called differentiation, and create special types of cells. Muscle cells versus skin cells or nerve skins and on and on.
So what are the differences between embryonic an adult stem cells?
Embryonic stem cells are the cells within the protective layer of the blastocyst. They are pluripotent, which means they can develop into any of the cells of the adult body. Researchers believe that, because they are pluripotent, and easy to grow, they have the best potential for replacing damaged or lost tissue or body parts. Also known as progenitor cells or somatic stem cells, adult stem cells are located, in small quantities, throughout the body and generate specialized cells for the area they are located. These cells do not renew themselves as well as embryonic stem cells. Still, if these cells are put in a different environment, they may produce a different type of cells from the originating cell.
Stem cell research is an active area of inquiry and scientists are discovering new characteristics of stem cells every day. Recent research indicated that multipotent stem cells from one type of tissue, in this case “blood”, might actually have the ability to generate cells for a different type of tissue like “nerves.” Scientists world wide are continuing to search for new sources of adult stem cells. Some of the locations where stem cells have been located include: bone marrow, skin, liver, blood, and the brain.
Some adult stem cells, which have already been used to treat illnesses, include hematopoietic stem cells and umbilical cord blood stem cells. Hematopoietic stem cells, however, are located in the bone marrow and form blood cells. They have been successfully used to treat blood disorders for younger patients. Umbilical cord blood stem cells are located in the blood of the umbilical cord after birth. Umbilical cord stem cells are similar to hematopeitetic stem cells in adults, but they are less mature and have much more potential to differentiate into various types of cells.