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First results of a Zurich clinical trial with paraplegics, 12.09.2012

Can stem cells help paraplegic patients? Which cells are safe to use? In an attempt to find some of the answers, Armin Curt from the University Hospital Balgrist and his team have injected stem cells within the scope of a strictly defined clinical study last year. Armin Curt presented the first results at a conference in London.

Increased sensitivity
The cells that were used are progenitor cells cultured from fetal brain tissue by the Californian company StemCells. The cells were injected in intact nerve tissue directly above or beyond the test persons’ almost entirely severed spinal cord. According to Curt, in the months following the injection, two of the patients - one significantly more than the other, developed a degree of sensitivity to temperature changes and touch in parts of the body between torso and navel which were completely insensitive prior to the trial.

This was reported by the patients themselves on the one hand. On the other hand, via electrodes fixed on the patient’s head, it was possible to establish that the nervous stimulus caused by touching the skin was actually transmitted to the brain. The stimuli must have been retransmitted via the spinal cord, underlines Curt. The results observed are indeed astonishing. However, it is not proven at all that the observed improvements are due to the injected cells. It is known for a spinal cord not completely severed to spontaneously start retransmitting stimuli in the months following the injury and for the patient to recover some sensitivity.
At present it is not clear either what effect exactly the injected cells may have had. The most probable explanation, according to Martin Schwab from the Institute of Brain Research of the University of Zurich, is that they produced molecules which encouraged or initiated regeneration of the damaged nerve tissue. For many years now, Schwab’s research focus has been on molecular biological mechanisms for improving therapies against paraplegia. It is also conceivable, although much less frequent based on the results on animals, that regeneration of the protective myelin coating which is essential for the transmission of stimuli was stimulated. Or, that new nerve cells were generated which then entered in contact with the existing ones.

Many unanswered questions
Curt and Schwab both insist that the results presented do not provide proof yet of the effectiveness of stem cell therapy against paraplegia. There is no basis for the promise of a new treatment. At the same time, says Curt, no negative secondary effects were registered until nine months after the trial and the patients will remain under observation during another four years. Based on the encouraging results, the Zurich research team will go on to treat another nine paraplegic patients within the scope of a clinical trial already approved by Swissmedic, the Swiss agency for the authorization and supervision of therapeutic products .

Translation of an article published in German in the 'Neue Zürcher Zeitung' on 12 September 2012.
Read the original article in German>>