This Is MS Multiple Sclerosis Community: Knowledge & Support

Schwann cells are the myelin producing cells of the peripheral nervous system. Attempts have been made to transplant them into the central nervous system, but without much success. Using more immature Schwann cells, however, might be a way of overcoming some of the problems and raises an intriguing possibility: Schwann cells are not attacked during the MS disease process, so one day it might even be possible to remyelinate axons before the disease is cured, (that's just speculation on my part).

Schwann cell precursors: a favourable cell for myelin repair in the Central Nervous System.Woodhoo A, Sahni V, Gilson J, Setzu A, Franklin RJ, Blakemore WF, Mirsky R, Jessen KR.
Department of Anatomy and Developmental Biology, University College London, London andCambridge Centre for Brain Repair and Department of Veterinary Medicine, University of Cambridge, UK.

Cell transplant therapies are currently under active consideration for a number of degenerative diseases. In the immune-mediated demyelinating-neurodegenerative disease multiple sclerosis (MS), only the myelin sheaths of the CNS are lost, while Schwann cell myelin of the PNS remains normal. This, and the finding that Schwann cells can myelinate CNS axons, has focussed interest on Schwann cell transplants to repair myelin in MS. However, the experimental use of these cells for myelin repair in animal models has revealed a number of problems relating to the incompatibility between peripheral glial cells and the CNS glial environment. Here, we have tested whether these difficulties can be avoided by using an earlier stage of the Schwann cell lineage, the Schwann cell precursor (SCP). For direct comparison of these two cell types, we implanted Schwann cells from post-natal rat nerves and SCPs from embryo day 14 (E14) rat nerves into the CNS under various experimental conditions. Examination 1 and 2 months later showed that in the presence of naked CNS axons, both types of cell form myelin that antigenically and ultrastructurally resembles that formed by Schwann cells in peripheral nerves. In terms of every other parameter we studied, however, the cells in these two implants behaved remarkably differently. As expected from previous work, Schwann cell implants survive poorly unless the cells find axons to myelinate, the cells do not migrate significantly from the implantation site, fail to integrate with host oligodendrocytes and astrocytes, and form little myelin when challenged with astrocyte-rich environment in the retina. Following SCP implantation, on the other hand, the cells survive well, migrate through normal CNS tissue, interface smoothly and intimately with host glial cells and myelinate extensively among the astrocytes of the retina. Furthermore, when implanted at a distance from a demyelinated lesion, SCPs but not Schwann cells migrate through normal CNS tissue to reach the lesion and generate new myelin. These features of SCP implants are all likely to be helpful attributes for a myelin repair cell. Since these cells also form Schwann cell myelin that is arguably likely to be resistant to MS pathology, they share some of the main advantages of Schwann cells without suffering from the disadvantages that render Schwann cells less than ideal candidates for transplantation into MS lesions.

PMID: 17550908 [PubMed - as supplied by publisher

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Dom

Oh lookit that cute little face, I just want to pinch those cheeks!!

What, you just start posting again with no "I missed you guys" or "sorry I scared the bejesus out of everyone"??

HEY!! Take a minute right now and write your password down and tape it to the computer stand.

Good to have you back you ornery old scutter! (not sure what that means. Festus used to say that to Doc all the time and it was obvious that they were pals)

Bob

Hello there Bob,
I thought I'd sneak quietly in and hope nobody noticed! Actually, I did post something last night and wrote a little "it's good to be back" speech at the beginning of it, but almost immediately realised Ian had got there before me and deleted them again.
This website is almost impossible to get back into if you've lost all of your log in details, (even on my backup drive), and it was only by chance that a couple of bored neurons managed to summon up the strength to produce a feeble spark, and thus remember the important bits.
Anyway, it really is nice to be back,
Dom
PS. Please let go of my cheeks now.

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Dom

Gol darn, maybe Ian was serious about Arron having a lapse in judgment and making him senior moderator! Come to think of it, I've had a couple of nice parasite immunomodulation posts disapear recently too!

As with any situation there is a silver lining in this one. While most people might consider moral fiber a necessary virtue for a senior moderator, I find comfort in knowing that if I get kicked off the site I can bribe my way back in!

That was just a figure of speech Dom, I like girls! Why, are you available??
Bob

Sorry Bob, I didn't make myself very clear. What I meant to say was that I had placed a couple of posts about some news I thought I had discovered, and at the beginning had written a paragraph thanking everyone for their concern at my absence and the PM's they sent me. I then realised that Ian had already posted those news-items so I deleted my entry immediately. Following that, I thought I might as well just carry on posting as normal.

And yes: horribly, permanently, distressingly available

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Dom

Either way, welcome back Dom. I can't quite put my finger on it, but your posts now have a kind of new computer je ne sais quoi about them...

I know that is french, but what does it mean?

My posts now have the added sheen of Windows Vista which, incidentally, has an excellent speech recognition program already built in – it's tucked away out of sight in the accessories menu, but it could be really useful for anyone who finds typing a bit of a chore or completely impossible.

" Je ne sais quoi", is French for, " what the *?#@!! was my password?"

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Dom

Hi Dom,
Considering you are the prim and proper Englishman type I should have given you the benefit of the doubt. You have redeemed yourself!

I hate to be so conniving but that worked exactly as I planned. I wanted to make that public because since you've posted the picture of Sean Connery in his youth, you wouldn't believe the number of hot thisisms chicks who have asked me if that "hunk" was available. Now the situation is out of my hands. If there are stalkers among them.........well, that would just be an added bonus!!

Bob

I always perk up when I see someone's studying both the CNS and PNS together, because I've been diagnosed with both MS and a hereditary peripheral neuropathy, HNPP. I'm pretty much demyelinating all over the place. I also have other relatives dx'd with MS or HNPP (Coincidence?), but so far I'm the only one with both.

I know remyelination always seems like a good idea, but my myelin-hungry system would probably just gobble these cells back up again and spit out a new lesion.

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Dx'd with MS & HNPP (hereditary peripheral neuropathy) 7/03 but must have had MS for 30 yrs before that. I've never taken meds for MS or MS symptoms except 1 yr experiment on LDN. (I found diet, exercise, sleep, humor, music help me the most.)

Hi euphoniaa,

I just read the medline explanation of HNPP because I wasn't familiar with it but I still don't know how much of a problem it is in itself.

Among your relatives who have HNPP alone, has it been debilitating...or maybe it's better to say "how debilitating has it been"?

Just out of curiousity...and if you don't mind, what were you diagnosed with first (MS or HNPP) and how do they diagnose HNPP and how certain is a diagnosis of HNPP?

Thanks,
Bob

My dad was dx'd with HNPP by genetic testing (a missing myelin gene) years ago and I've read that 50% of their offspring will have it as well. I was sent to the same specialist (a physiatrist) when I mentioned to my doc that I had a tremor in one finger. EMGs showed carpal tunnel-like blockage, leading him to suspect HNPP, but he also sent me for an MRI of the brain and c-spine. The next day he said that he was almost 100% sure I also had MS due to my brainful of lesions.

Subsequent testing by a neuro (LP, evoked potentials) confirmed MS, and more EMGs confirmed very probable HNPP due to carpal tunnel in both wrists and both elbows. I have no idea how my 2 cousins were dx'd with MS and HNPP. I only recently found out about my cousin's HNPP and haven't talked to him yet.

Dad uses an AFO for footdrop, takes Neurontin for nerve pain, and can barely make it from the house to the car using a walker, but he's also in his 80s. One of my neuros said it's impossible to tell whether my tremor is due to MS or HNPP, and I use a cane for footdrop. MS or HNPP? Who knows?

I got my first cell phone a while back, made a 10 minute call, and by the time I was done my right arm was completely numb all the way to my elbow. It took 2 weeks for the numbness to gradually go away. That's HNPP.

HNPP can easily be diagnosed with a genetic test, but they understand it even less than they do MS so it's underdiagnosed and untreatable. It's progressive, but not always disabling.

Although the CNS claims the really important nerves like the brain, spine, optic nerve, all the rest of our nerves are peripheral nerves. It's entirely possible that every one of my symptoms can be attributed to HNPP rather than MS, but we'll never know for sure. MS trumps HNPP with neuros.

Here's some more info:

http://millercenter.uchicago.edu/learna ... hnpp.shtml

http://www.geneclinics.org/profiles/hnpp/details.html

I'm sure this is more than you wanted to know... Sorry.

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Dx'd with MS & HNPP (hereditary peripheral neuropathy) 7/03 but must have had MS for 30 yrs before that. I've never taken meds for MS or MS symptoms except 1 yr experiment on LDN. (I found diet, exercise, sleep, humor, music help me the most.)