Thursday, March 11, 2010

Prions

The wet lab today was excellent, not least because I successfully removed a cow's spinal cord on the first go. With a grapefruit spoon. The sheep's spinal cord was trickier, and I'm afraid I shaved off half the section I was supposed to be retrieving, but hey, I found the tonsils! And the retropharyngeal lymph nodes too. An entire year of anatomy and it took a fresh sheep head to make me realize where the darn things are located. It becomes much more relevant when you are trying to obtain samples for very specific histologic testing. In anatomy, it was just, "tell the difference between fifteen different pinkish squishy bits of tissue."

I don't think any of the heads we were working with were scrapie-positive (though with sheep, you never know), but the demo head did come from a deer with CWD symptoms. I have been in the same room with prions...

If only prions weren't so potentially super-super-scary, they would be an awesome thing to study. However, as it is, they seem a little too subtle for working with. In some ways, they are in the same category with tuberculosis and smallpox; the deadly diseases that are so subtle that they've already escaped control again (granted, smallpox has been declared eliminated. But the book Demon in the Freezer makes a pretty convincing case that it would be too easy for it to make a reappearance).

I think this is what makes parasitology so appealing on one level: all you have to do is look, and if the worms are there you'll see them. And you can even remove them by hand if all else fails (sometimes). They make us squirm, but it is productive squirming! Prions, on the other hand, are virtually undetectable and insidious. They can't be killed, they can't be stopped, all you can do is avoid them and try to make sure they don't spread. Which is why CWD is a scary thing, for all that its impact hasn't really been seen yet. Deer across the country are seeding the ground with prions, and no one knows what's going to happen. But the impact, if any, is so glacially slow in becoming apparent that very little action is being taken.

Brr. Yeah, it was an excellent wet lab, but not the sort of stuff that makes you sleep soundly at night.

1 comment:

Sal said...

That sounds awesome...I can't wait till vet school. I am a more hands on kinda guy, so I know what you mean by actually having to find stuff to figure out where it is :) Labs are fun.