Blog on the "Spinal Repair" Jasper Dog story on the BBC
The full paper is open access and available here.
A nice commentary by James Guest is available here, (but you may have to pay for that!).
I have been told that some of my tweets looked a bit negative? ...that is totally wrong, this is an exciting area of research and I believe it is very possible that, eventually, we will have some treatments start to appear. But the rub is in the word "eventually" :-(
My negativity is in the reporting. The media are building the work up beyond its own conclusions and really should keep calm and take the opportunity to educate the public, not dumb it all down.
I first heard about this work many years ago (a talk with one of these authors in fact) and it's authors are smart and thoughtful scientists. Pretty much any limitation you would think of, they are perfectly aware of... but they are doing their best!
Some points, feel free to correct me in the comments if I have something wrong!:
(1) Long tract function failed to improve. I.e., there is basically a set of "master neurones" in the CNS which project all the way from the brain to the level of the hind limbs, bladder etc. I would be pretty delighted to see paralysed dogs walk again too (obviously!)... but if we are to have paraplegic humans walk again we would probably need these neurones repaired. Sadly there was no evidence of this. That's not surprising of course. If you chop a motor nerve... I would have expected that whilst the top end may survive, the bottom end (below the damage) will just shrivel up and die... (so you have an obvious worm analogy here) therefore, what is the poor old implanted cell supposed to do? It doesn't really just need to bridge a little gap... it would have to cause an entirely new "end bit" to grow. That's a tougher ask of course. So if the damage is way up the cord... it would have to grow down several inches. If you are lucky... the lesion is right at the point where the descending neurones synapse (connect to) the final neurone. The final neurones then head straight out of the cord and innervate (connect to) the actual muscle. If that was the case... it may be possible for the new "growth" to simply make a new connection within the spinal cord.
(2) So what did improve? Co-ordination between front and hind limbs. This is a more tricky parameter to assess...... to start with... motor movements of a hind limb (of a dog/cat) on a treadmill will actually be generate locally? i..e., if you pull the leg back it will, to a certain degree spring back and forth by reflex actions . This is sometimes referred to as "spinal walking" (Spinal walking physiology paper). It is not real walking [video]. So it looks like walking although it isn't. So the co-ordination is actually quite a subtle thing to measure. It isn't really even understood exactly how it works either, but there are various nerves which run between each of the four limbs and it appears that these are the ones, if any, which have improved.
(3) Could the statistics be flawed I hear you ask.... Well of course there is one way in which trials easily can be fudged, but that won't be the case here!! ...if you ran enough trials, by pure chance you could expect that one trial would throw up an apparently statistically significant result. You could just then publish that one and say nothing about the others! ...I'm sure that this is not the case with this this one (well I'm not sure, but I simply can't believe that would be the case!!!!)
Final thoughts.... Jasper was lovely!!! I wish him well and I sure hope he has a long and spritely life!
Olfactory ensheathing cells on Wikipedia
Neurone = the individual cell
Nerve = the whole nerve bundle
CNS = central nervous system.
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