Helping Resolve Part of the Stem Cell Debate
Thursday, March 02, 2006 - Stem Cell Guru
The article below, authored by Dr. Grant Morrow, Medical Director of the Columbus Children's Research Institute at Children's Hospital is a useful primer for anyone visiting this blog for the first time and who requires a brief overview of the diffrences between embryonic and adult stem cells. One glaring omission, however, is the simple fact that adult stem cells can also be harvested from a patient's own blood in addition to bone marrow.
Human stem cells have unique characteristics. For one, they are unspecialized in the sense that they don't perform a specific function in the body until they are stimulated to change. For example, cells that help the heart beat or produce insulin.
This ability gives them enormous potential to treat diseases. One might characterize the fertilized egg as the ultimate stem cell because it eventually differentiates into a complete human being.
There are two types of stem cells - embryonic and adult.
Embryonic stem cells are present at the fourth to fifth day after fertilization. Because these cells can divide and renew themselves in the laboratory for a long time, they can be grown in large enough numbers to treat a variety of diseases. They also have the greatest potential to differentiate into various types of specialized cells.
Adult stem cells, on the other hand, are located in various organs and help maintain and repair them.
Adult stem cells, however, cannot renew themselves as much in the laboratory and do not have the potential to differentiate into other cells as completely as embryonic stem cells.
In the 1960s, researchers discovered that adult bone marrow contained stem cells that could differentiate into any blood-cell type of the body. As a result, bone-marrow transplants have become effective, standard treatment in many patients with cancer.
However, obtaining bone marrow stem cells requires matching donor and patient and performing an operation to obtain the bone marrow.
Blood from a newborn's umbilical cord contains large numbers of stem cells that can be used as an alternative source. Cord cells act as adult rather than embryonic stem cells.
Since cord blood is routinely discarded, its use for transplantation should minimize ethical concerns.
Researchers have compared the use of bone marrow versus cord blood cells to treat cancer and found that both approaches were equally effective.
A major advantage of cord stem cells is that they can be grown in the laboratory, and matched and stored for future use.
Solving the technical and ethical issues regarding the use of stem cells will require more research, but the discovery that cord blood can be one additional source of adult stem cells is a major advance.
How we harness and use the greater potential of embryonic stem cells is an issue that will require time to resolve.
Human stem cells have unique characteristics. For one, they are unspecialized in the sense that they don't perform a specific function in the body until they are stimulated to change. For example, cells that help the heart beat or produce insulin.
This ability gives them enormous potential to treat diseases. One might characterize the fertilized egg as the ultimate stem cell because it eventually differentiates into a complete human being.
There are two types of stem cells - embryonic and adult.
Embryonic stem cells are present at the fourth to fifth day after fertilization. Because these cells can divide and renew themselves in the laboratory for a long time, they can be grown in large enough numbers to treat a variety of diseases. They also have the greatest potential to differentiate into various types of specialized cells.
Adult stem cells, on the other hand, are located in various organs and help maintain and repair them.
Adult stem cells, however, cannot renew themselves as much in the laboratory and do not have the potential to differentiate into other cells as completely as embryonic stem cells.
In the 1960s, researchers discovered that adult bone marrow contained stem cells that could differentiate into any blood-cell type of the body. As a result, bone-marrow transplants have become effective, standard treatment in many patients with cancer.
However, obtaining bone marrow stem cells requires matching donor and patient and performing an operation to obtain the bone marrow.
Blood from a newborn's umbilical cord contains large numbers of stem cells that can be used as an alternative source. Cord cells act as adult rather than embryonic stem cells.
Since cord blood is routinely discarded, its use for transplantation should minimize ethical concerns.
Researchers have compared the use of bone marrow versus cord blood cells to treat cancer and found that both approaches were equally effective.
A major advantage of cord stem cells is that they can be grown in the laboratory, and matched and stored for future use.
Solving the technical and ethical issues regarding the use of stem cells will require more research, but the discovery that cord blood can be one additional source of adult stem cells is a major advance.
How we harness and use the greater potential of embryonic stem cells is an issue that will require time to resolve.
Site Feed
0 Comments:
Post a Comment
<< Home