stem cell sources

Sources of stem cells

There are different types of stem cells. Each type of stem cells has its own scope, there are several possibilities for research and play other public discussions. Below is a list of sources of stem cells.

1. Embryonic stem cells
This meant stem cells from fertilized eggs or embryos are removed. Embryonic stem cells can still develop into any body cell. A fertilized egg grows into a complete human being after all.

Embryonic stem cells are not used for treatments. They still used for research on (in) fertility and the development of organs like the heart.

In the Netherlands, only embryonic stem cells extracted from embryos left over from fertility treatments. Embryos are allowed under the Embryo research is not specifically made.

Cloning of twins
When a sperm fertilizes an egg an embryo is created. The embryo gets half of the genetic material of the father and half from mother. This creates a new, unique person.

If you are an early embryo consisting of two parts, both parts can yield a completely healthy person. This occurs naturally when identical twins. But in the lab this could in theory be repeated many more times, so you speak of cloning. It is forbidden to clone, ie these clones in the uterus back into place.

Cloning in science
Normally receives an embryo, as mentioned by both parents half the genetic material, so again volldige a new set of results. But in the laboratory is also the complete set of genetic material from, for example a skin cell into an empty egg placed. The egg has the same genetic material as the owner of the skin cell.

This is often referred to as the science of cloning is discussed. Researchers would like to get stem cells from an embryo that, as in normal embryos. When these stem cells can be cultured tissues ever, these same genetic material could have if the patient, eliminating disposal would take place.

It has so far not succeeded in an oocyte containing genetic material from a donor clone. Korean scientists have published it into several highly regarded scientific journals, but turned out that the results were fraudulent.

Therapeutic or reproductive?
If you have a cloned egg is used to make stem cells for medical purposes, it is called therapeutic cloning. The clone was made for someone to heal them. In practice, this never happened.

When a cloned egg is placed in eem uterus can grow there, like Dolly and Snuppy. This is called reproductive cloning. The clone is made to a individue of the owner of the genetic material to reproduce.

Reproductive human cloning is banned worldwide.

2. Adult stem cells
Adult stem cells still occur in the body of children and adults. They are called adults to indicate that they are more developed than embryonic stem cells. Adult stem cells can often until every cell in the body where they are developing. But not for every body, as embryonic stem cells. Almost daily, new types of adult stem cells discovered. Sum concerns stem cells into organs where they were not seen, but often they are slightly different species from what is known so far.

Adult stem cells are already being used in the treatment of leukemia, metabolic disorders and zelfzame Several hereditary anemia. This relates to stem cells from bone marrow and umbilical cord. These stem cells can have all the blood cells from forming.

Adult stem cells that can more
Research is often focused on the properties of adult stem cells embryonic stem cells to give back. Firstly because the use of embryonic stem cell research and therapy is controversial and an alternative route could take many objections. Another advantage is that this custom of the patient's own adult stem cells originate, so a treatment with no immune cell reaction.

Researcher at the University of Minnesota has found evidence that the bone marrow cells are also mature stamm that it can form many different tissues, like embryonic stem cells.

But since the discovery of these cells, called MAPC's, it proved difficult to repeat the research. Moreover, there is debate about the reliability of the published results.

3. Stem cells from cord blood
Also, cord blood and umbilical cord itself are a rich source of stem cells. These cells are adult stem cells. They have the same potential as stem cells from bone marrow. One advantage is that the decrease of these cells is painless and that they are less likely rejection reactions.

Parents can the stem cells from the umbilical cord to save a stem cell bank. There is a difference in store for general use and storage for personal use.

4. Stem cells grown from skin cells
In the autumn of 2007, Japanese and American researchers have succeeded in by 'reprogramming' of human skin cells to create cells in the laboratory is indistinguishable from embryonic stem cells.

Scottish researchers let them know the technique used to make Dolly the sheep, not to investigate people. They found the new technique better suited. Technical, as well as there is not need eggs.

The new technique is still very new and it is hard to predict what the utility will be. But in theory, stem cells are programmed an ideal alternative to embryonic stem cells, where embryos are used. There are many objections to ethsiche.

The first cells with DNA of patients have already been made, which is very soon after the discovery of the principle. Cells with DNA of patients are very important for stem cell research into diseases specific to do.

In theory the technique could also be applied to other body cells, but so far have used skin cells.