Successful treatment for paraplegics: In the USA, the first trial run of stem cell therapy for patients with acute spinal cord injury started.
A new stem cell therapy could help paraplegic patients with a spinal cord injury in the future. For the first time, doctors at the "Shepherd Center" hospital in Atlanta underwent stem cell-based therapy. For this purpose, the partially paralyzed patient in the injured body region was preceded by nerve cells The affected patient had only had a significant injury to the spinal cord two weeks ago, so that he was sometimes unable to move.
Nerve cell precursors should develop in the back market and stimulate nerve processes to grow
The injected nerve-cell precursors are said to develop into so-called “oligodendrocytes” in the patient's spinal cord. These cells are responsible for the formation of myelin sheath around nerve cell processes. The myelin layer is a kind of insulation, which is also responsible for the conduction of the electrical impulses from the brain to the body parts as well as for the signals from the sensory receptors to the brain. The researchers and doctors hope that the injected cells will stimulate the severed nerve processes to grow. This would allow the injured signal lines to be put back together. The patient could regain sensations and control of the paralyzed areas of the body.
However, modern stem cell therapy is not without controversy among scientists. Regardless of ethical reservations, injecting stem cells can lead to undesirable side effects. As such, stem cells are very miraculous and can form any cell type. And because they do that, they shouldn't actually get back into the body. Because so-called teratoms can then form there. These are tumors in which all kinds of tissues can be found, from hair to eyes and teeth. Cell therapy is therefore only possible if these stemmed from stem cells and all other cells have been carefully separated. So far, however, this process has been almost impossible.
The first experiments on animals were successful
The biotechnology company "Geron" announced that it was possible to partially restore the mobility of mice injured on the back market in animal experiments by means of a test arrangement. So far, it is uncertain whether these results can actually be transferred to the human organism and what effects could result. The biotechnology group had previously registered a phase I trial with the FDA in early 2009. However, the U.S. health agency had denied approval because cysts had formed in the rodent's spinal cord after the transplant, and the company started a new study and resubmitted to the regulatory agency, and the FDA approved the new test results. In the new study, the company claimed that the cysts were common in spinal cord injuries anyway, and had no harmful effects on humansExperimental set-up and therapy changed accordingly so that fewer cysts form.
Test phase one of stem cell therapy in humans
This first intervention is therefore initially an experimental arrangement in humans. The focus here is not on the effectiveness of stem cell therapy, as is often assumed, but on whether side effects and complications arise. Although the scientists also want to check whether the patient's condition improves, tolerability and safety are the focus of the doctors. A further 9 out of 10 patients are now to receive stem cell therapy. It is important that the spinal cord injury to all patients was not more than two weeks ago.
If it was found that stem cell therapy does not produce any serious side effects, a second test phase is used to determine whether the effectiveness of the dose can be optimized. If the second phase of the test series is successful, the third and last phase follows. The final efficacy should then be demonstrated in a larger group of patients. Provided that all studies were actually successful, this means that stem cell therapy for acute spinal cord injury could only be offered in around 15 years.
The risk of tumors due to genetic defects is relatively high
However, the casually mentioned cysts cause scientific criticism. Stem cell therapy is far from uncontroversial. Other researchers point out the increased risk of cancer that can be triggered by injecting stem cells. Because that lurks in human DNA, which is also transmitted in embryonic stem cells. Because when cells are cloned, the body's own repair mechanism does not work. The result is genetic defects in the cells that are also transmitted during treatment. John Gearhart, stem cell researcher from the University of Pennsylvania told the Washington Post: "We absolutely need to find out how these cells behave in humans." With this, the expert expresses fears that tumors could form through stem cell therapy. Until now, it is not known whether the cells do what they are supposed to do. If they don't, the risk of mutations is high. (sb, October 13, 2010)
Stem cell therapy for spinal cord injury