February 6, 2013
The Most Common Sources of Stem Cells Today
In this century, although things can happen at the speed of thought, there remain many diseases that cannot be treated effectively through conventional methods. Diseases like Alzheimer’s and Parkinson’s continue to plague modern man. .Foro a large population of people afflicted with these diseases and many others, stem cell therapy provides a glimmer of hope. However, there has been a lot of controversy surrounding stem cell research and therapy; much of it arising from the misconception that all stem cells come from human embryos.
Current Approved Sources of Stem Cells
Specifically, for transplantation purposes, stem cells can be extracted or harvested from the following sources: the umbilical cord blood from newborns, the bloodstream which is also referred to as peripheral blood, and bone marrow. Another source linked to cord blood that is being studied today is the placenta or afterbirth which is usually considered medical waste.
Umbilical cord blood
Of all stem cells, umbilical cord stem cells present the least problems in terms of ethics and legality. After birth, blood that is left in the placenta and the detached umbilical cord is simply taken, stored and frozen for later use. Though the harvest from umbilical cords is quite small, each stem cell gathered from cord blood has a greater capacity to form more blood cells than those gathered from adult bone marrow.
Sometimes people who need a stem cell transplant cannot find a well-matched donor. In this instance, umbilical blood cord may be the answer. So far, most cord blood transplants have been done on children and smaller adults but studies are being conducted to be able to use cord blood for transplants in larger adults.
Stem Cells from Bloodstream
A few days before stem cells are harvested from the bloodstream or peripheral blood, the donor is given substances that promote stem cell growth and causes them to migrate into the blood. During the extraction process, a catheter is inserted into the donor’s vein; the blood then flows from this tube directly to a machine which separates the stem cells from the blood. The rest of the blood flows back into the donor’s system; the isolated stem cells are filtered, stored and frozen until the transplant is performed. This is a process that takes hours and it is one that may need to be repeated for several days until a sufficient amount of stem cells have been harvested.
After the patient has undergone either chemo or radiation or both, the harvested stem cells are infused into the patient’s bloodstream. These travel to the bone marrow where they become engrafted. The stem cells then grow and make new normal blood cells. Evidence of new normal blood cells is usually found in the patient’s blood a few days sooner when the transplant comes from blood stream stem cells than when bone marrow stem cells are used.
Bone Marrow Stem Cells
The bone marrow, the spongy tissue found at the center of bones, is responsible for making red blood cells that circulate in the system and white blood cells which fight infection. The bone marrow is a very rich source of stem cells; particularly the marrow in the pelvic bone.
To extract bone marrow, a large needle is inserted into the back of the hip bone so that the thick liquid marrow can be pulled out. This is done repeatedly until sufficient marrow has been harvested. The marrow is then filtered, stored and frozen in bags with a special solution till it can be used. Donors go through this evidently painful process under general anesthesia so they do not feel any pain. Care is take to ensure that they do not suffer from infection after the procedure.
Having the three sources of stem cells is a great advantage in the medical field today and research is being aggressively undertaken to make sure that all options are explored to arrive at effective treatments. As more and more people receive the benefits of stem cell therapy, no doubt the support for stem cell research will grow and making full use of stem cell sources can be further maximized.