A recent project conducted by Dr. Mark Post, reached a milestone last month when journalists were treated to the first stem cell hamburger. Actually, meat pattie is probably a better description as they skimped on the bun, the tomato, lettuce and special sauce. Considering that the project cost approximately 250,000 euros you would have thought they might have thrown a few gherkins in.
This is just the latest use of stems cells, all be it, non human stem cells. The outcome of this experiment suggests that in the distant future we may not have a need for cows. Whether that is good news for bovines or not is another question for another time. In this article we are more concerned with the uses of human stem cells and specifically the sources of human stem cells.
Stems Cells – What’s The Big Idea ?
Stem cells can be grown into any tissue in the human body. That’s the theory at this stage but hopefully a reality for people who want this research to progress as quickly as possible.
This will allow scientists to experiment on these cells to learn how to solve common illnesses and diseases. This will allow them to develop drugs (or other solutions) to these illnesses faster than they currently do.
Furthermore, body tissues and organs may be able to be grown in a “test tube” or “petri dish” and later transplanted into people with failing organs, thus prolonging their lives.
So in short, stem cell research could solve many common illnesses and prolong human life.
Sounds good but there are ethical issues. The principal issue is that the stem cells are taken from a live human embryo. Whilst there is some debate about this being true, for people against the use of stem cells, it’s the thin end of the wedge. It will lead to sanctioned murder in the name of scientific progress.
With this in mind are there other sources of stem cells that get round the ethical issue ?
There sure is.
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.
Induced Pluripotent Stem (IPS) cells
These are stem cells that are taken from adult somatic cells so there is no need to use embyronic stem cells. The somatic cells are taken from a grown adult and inducing a “forced” expression of specific genes so that the cells are altered. Induced stem cells are often taken from the following parts of the body :
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.
IPS cells have also been made from adult stomach, liver, skin cells
Given the potential that stem cell research holds to solving illnesses and prolonging life, it seems that using these ethically sound options could be the way forward.