Stem cell transplantation can lead to a cure for hematopoietic diseases such as leukemia. The treatment is also known as a bone marrow transplant. The various blood cells are formed in the bone marrow. The principle of the therapy is to first remove the degenerated cells and replace them with healthy cells. Ideally, this allows the body to produce healthy blood again.
Here you will find further information as well as selected specialists and centers for stem cell transplantation.
Many patients suffering from leukemia or other blood diseases have high hopes for stem cell transplants.
This involves transferring the blood stem cells of a donor to the patient. Ideally, this "reset" of the disturbed blood formation makes a complete cure possible. The problem with stem cell transplantation is the search for a suitable bone marrow donor.
Stem cell transplantation is also called bone marrow transplantation.
The human organism is made up of individual cells, which together form the various organs. The individual cells have to fulfill different tasks: A skin cell on the nose must have a different composition than a cell in the large intestine or in the bone. After all, you can't use a molar tooth in the heart muscle.
The body knows which cells it needs in which place thanks to the blueprints laid down in the genetic code of the genome. It needs the stem cells in order to produce the right cells for the desired task. Stem cells are the starting point for the entire structure of the human organism.
There are also numerous specialized cell types in the blood, such as
Blood cells are not particularly long-lived and are therefore constantly being produced in the bone marrow. Special stem cells are located there, which are exclusively responsible for the production of different blood cells. If diseases (e.g. leukemia) lead to overproduction or the production of abnormal cells, this can have life-threatening consequences.
Ideally, a stem cell transplant will restore healthy blood formation © Henrie | AdobeStock
If doctors diagnose such a disease, they must decide on an appropriate therapy. This can vary greatly from person to person. The choice of therapy depends on the type of disease. The generic term leukemia includes a large number of different forms, all of which require a specific approach.
Lymphomas (malignant diseases of the lymphatic system) and certain diseases of the immune system can also respond to a stem cell transplant.
The idea behind the treatment is similar to resetting the operating system of a computer: the pathological and faulty production of blood cells is first stopped. Then the hematopoiesis is "restarted" with healthy stem cells.
First, the immune system and the bone marrow are treated with radiotherapy and/or chemotherapy. Ideally, all pathological cells should be destroyed. This first step is called conditioning.
The doctors then transfer healthy bone marrow to the patient through a vein. The blood stem cells contained in the stem cell donation settle in the medullary cavities of the patient's bones. Within a few weeks, they should have completely replaced the original bone marrow.
However, due to the elimination of the body's own immune system, there is a greatly increased risk of infection for the patient during this time. Rejection reactions to the foreign donor material can also occur.
Most people only talk about bone marrow transplants. However, this is not the only option for transferring blood stem cells.
In the past, bone marrow was taken from the donor under general anesthesia. For this purpose, a relatively large needle was inserted into the iliac crest (near the hip) and a corresponding amount of bone marrow was removed. This material was then processed in the laboratory and the stem cells were then administered to the recipient as in a blood transfusion.
The risk for the donor is very low - apart from the general anesthetic and the usual risks and side effects associated with it. The donor site may still be sore for a few days.
However, the word bone marrow transplant often causes misunderstandings among laypeople. It prevents many people from registering as donors at all. Many confuse bone marrow with spinal cord. But bone marrow transplantation has nothing to do with this. There is clearly no threat of paralysis or other risks that would be expected in a spinal cord operation.
This is why doctors today prefer to speak of stem cell transplantation.
However, there is now also another procedure for transferring blood stem cells: Peripheral stem cell harvesting. The required blood stem cells can be obtained directly from the donor's blood. This procedure is possible in around 80 percent of all cases.
For this purpose, the donor is given various medications before the collection, which encourage the stem cells to be flushed out into the bloodstream. The cells obtained in this way are then centrifuged and processed in the laboratory so that they can be administered to the patient.
Six to eight rounds of this so-called leukapheresis are usually necessary for a successful transplantation.
General anesthesia is not necessary for the donor in this case and the entire collection can be performed on an outpatient basis.
This procedure also appears to have therapeutic advantages: In many recipients, new blood formation is restored more quickly than with traditional bone marrow transplantation. However, for around 20 percent of donors, only a direct bone marrow donation is possible.
For the therapy to be successful, the new stem cells must be as compatible as possible with the patient. This is why it is so difficult to find a suitable donor. The aim is to identify a genetic twin.
If no donor can be found or if allogeneic transplantation is ruled out in principle, autologous transplantation can be attempted. This involves donating blood stem cells.
The patient's own blood stem cells are first removed during a remission (a phase of low disease activity). These can later be reimplanted. However, there is always a risk that pathological cells will re-enter the body in this way.
This form of treatment is mostly used for lymphomas and less frequently for acute and chronic leukemia.
Although all this is quite stressful for the patient and carries a high risk of infection, many patients have no other choice. After all, the procedure offers relatively good prospects of a cure in many cases, always depending on the individual case of the disease. Most patients therefore accept the risks and side effects.
For the donor, the procedure involves relatively little effort and risk. However, the search for a suitable stem cell donor remains the biggest challenge in the fight against leukemia and other blood diseases.
The Leading Medicine Guide's quality assurance is ensured by the following acceptance prerequisites.
