Restart the immune system for rheumatism

Stem cell transplantation in severe rheumatism: Restart the immune system

09/22/2013

In severe rheumatic diseases, stem cell transplantation can help. Radical chemotherapy first destroys almost all defense cells of the misguided immune system.

Immune system out of control
A kind of admission control protects our body against the entry of unwanted pathogens. Only cells that carry on their surface the most specific protein combination of every human being, are from the immune system „recessed“. This biological defense system removes foreign substances that have entered the body and can also destroy damaged endogenous cells. The immune system is vital and man is armed against most infections. However, this control sometimes gets out of control and fights instead of foreign bacteria and viruses then endogenous cells.

Autoimmune disease with varying severity
One speaks in such cases of autoimmune diseases. The symptoms, ranging from mild to sometimes even life-threatening, depend, among other things, on which cells are controlled by the immune system. Rheumatic diseases are also included. Symptoms and severity are very different and depending on which proteins are repelled by the immune system, it can lead to the well-known joint complaints or even to an involvement of the skin, kidneys and other organs.

Unclear why some people get rheumatism
So far, it is unclear in many areas, why some people get rheumatism and others do not. But some risk factors are known that affect both the onset of rheumatic diseases and the individual relapses. „Genetic factors play a role, but also external influences such as infections, stress, hormones and sunlight“, said Falk Hiepe, Senior Physician at the Medical Clinic focusing on Rheumatology and Clinical Immunology at the Berlin Charité. Rheumatic diseases have particularly serious consequences if they „systemic“ run, so if disease consequences occur in many parts of the body. Thus, in addition to the joints, skin and kidneys can be affected very often as well as kidney failure. In addition, there is a risk of circulatory disorders and functional limitations in the heart, lungs and in the gastrointestinal tract.

Consistent treatment important
In order to avoid impending progressive organ damage, a consistent treatment is particularly important in such diseases. For some cases, however, there are no helping drugs and so doctors came to a known from cancer treatment method, stem cell transplantation. Hiepe and his colleagues from the Charité reported on this extraordinary method at the last congress of the German Society for Rheumatology (DGRh) in Heidelberg and Mannheim. However, this only comes into question for a few patients. Only if the organ involvement causes serious long-term damage and medication can not stop the progression of the disease, try stem cell transplantation. According to Hiepe often with good results: „Some of our patients have not had a boost in over ten years.“

Exchange of the immune system
The patients owe their sudden improvement to the almost complete replacement of the immune system. After all, radical chemotherapy destroys almost all defense cells, including those needed. However, since healthy defense cells are still needed urgently, you will be provided with a pre-chemo blood collection. This is called a so-called „autologous“ Stem cell transplantation, since the stem cells come from the patient himself. Since a sufficient number of these cells can not be found so easily in the blood, their production in the bone marrow is artificially stimulated. The resulting high number of stem cells in the blood stream then ends up in the blood bank, which serves as the basis for the subsequent transplantation. From this blood, harmful autoimmune cells and other blood cells are removed to leave a stem cell-rich mixture which can be transplanted after chemotherapy.

Disease activity returns after treatment
The stem cells should then find their way into the bone marrow to build a new, healthy immune system there and without autoimmune cells. So far the theory. But a few autoimmune cells may be left behind despite chemo and careful sorting. „It can not be excluded that a small proportion of autoimmune cells in the body is retained, nor that a few autoimmune cells are transmitted by the stem cell therapy“, so Hiepe. „What we can say, however, is that the disease activity usually decreases significantly as a result of the treatment.“

Success also in neurology
Similar achievements have been made in another area of ​​medicine, neurology. For example, autologous stem cell transplantation may be useful in multiple sclerosis, but is rarely used here. „Treatment will only be considered if multiple sclerosis is in an early, very active stage with many relapses and other treatment methods have little effect“, said the neurologist Lutz Harms, expert for multiple sclerosis at the Berlin Charité. The reason why this method is rarely used depends on the progress of other treatments, such as the administration of specific antibodies directed against autoimmune cells. According to Harms, this treatment is therefore an absolutely experimental therapy that would be suitable for very few multiple sclerosis patients at all.

Stem cell therapies are viewed critically
Some neurologists warn against stem cell therapies. The German Society of Neurology (DGN), for example, advises against these expensive and unchecked stem cell therapies for neurological diseases. „Although stem cells have great potential in the development of new therapies, it is still urgently advised against their use in humans“, said Professor Alexander Storch at the DGN Congress. There are many expensive treatments in private clinics and practices that promise more than they hold. „There is no stem cell therapy for neurological diseases yet. "

Side effects in the foreground
For many rheumatic diseases, new methods are also used. Thus, more specific drugs promise better results here in the future, because the main problem of previously used drugs is that they dampen the entire defense system and often bring many side effects with years of use. „While no treatment was available in the past and the people concerned were therefore primarily struggling with the serious consequences of the disease, nowadays the side effects of the drugs are often in the foreground“, so Hiepe.

One year for new defense system
However, these drugs would still remain vital until now, because without them, the body's own destruction would continue to progress, possibly even with severe organ damage. Patients, however, must expect a certain susceptibility to infection even after a stem cell transplant, even if they no longer need immunosuppressants after treatment. In the chemotherapy, almost the entire defense system was finally turned off and the construction of a completely new body defense takes time. Hiepe explains that one has to expect at least one year for this process. In the future, it should be possible with the help of new drugs, targeted to destroy autoimmune cells, without doing the actual body defenses damage. Because even if a few defense cells could develop into misguided autoimmune cells, the rest are still doing a vital service to their health. (Ad)