oligodendrocytes

The 28 February 2004 issue of New Scientist contains a page 17 article on multiple sclerosis which makes me aware of a type of cell I knew nothing about, an 'oligodendrocyte,' which according to the article produces the mylein sheath that nerve cells need. Apparently a 14-year-old girl died of a bout of MS and they autopsied her and found that the oligodendrocytes were dying. This argues against the theory that the immune system was attacking the sheath.

I don't at this time know if sheath loss is an issue in ALS. I kind of get the impression that the motor nerves die, and that of course results in some myelin shedding. But I don't think there is a major theory that the motor neurons lose their sheath and that kills them. So, while interesting, this aticle about the oligodendrocytes may not be relevant.

Also in that issue, on page 27, is an ironically amusing article about the possibility of creating bionic limbs which would move naturally in response to the signals from the nervous system. That's all very fine for Christopher Reeve, but if your motor neurons are dead, as in ALS, it's kind of useless.