(gently) break on through to the other side

November 10, 2015 11:26 PM

Toronto researchers cross the blood-brain barrier for the first time. Dr. Todd Mainprize used a focused ultrasound technique, developed with collaborator Dr. Kullervo Hynynen and others, to non-invasively cross the blood-brain barrier to selectively and directly deliver a chemotherapeutic drug to a glioma. (Globe & Mail x 2). "Mainprize says the method could be used for all sorts of brain conditions besides cancer. "There are possibilities of delivering new chemicals and therapies for depression, Alzheimer's disease, stem cells," he said." (CTV)

"Here’s how it works: Medication is first introduced into a patient’s bloodstream – in this case, a chemotherapy drug called liposomal doxorubicin. Next, microbubbles, or tiny air bubbles, which are typically used as a contrast medium to enhance visibility in ultrasound imaging, are intravenously delivered into the bloodstream. Using MRI to locate their target area, doctors then send focused ultrasound waves, causing the microbubbles in the brain’s capillaries to expand and contract. This expansion and contraction creates little tears in the cling film-like layer of endothelial cells of the blood-brain barrier, allowing the drug molecules to pass through into the brain to the targeted areas." (G&M x 2)

(Sunnybrook Health Sciences Centre media release)

The trial, sponsored by InSightec, is still recruiting participants.

Ultrasound has also been used to non-invasively remove amyloid-beta plaques, the hallmark of Alzheimer's disease in humans, from the brains of mice.

posted by cotton dress sock (10 comments total)

huh. i've never really understood all this. but doesn't this also mean that other stuff can also pass through at the same time? in particular, white blood cells? as i said, i really don't understand this stuff (i know i should google, but frankly, shit's terrifying and i'm just sitting here wondering whether to press post and, if so, if i'm even going to come back to read replies, never mind start actively searching for bad news), but i thought one of the weird things about MS was that somehow white blood cells get through this barrier and start munching away at the CNS. so wouldn't this have a risk of giving people MS? (and, well, a whole pile of other diseases, i guess).
posted by andrewcooke at 2:19 AM on November 11, 2015

White blood cells are quite large, compared to single molecules. It says in the second link that the microbubbles themselves don't pass through the blood-brain barrier, which implies that the tiny tears are smaller than the bubbles that cause them. Presumably only very small things like the molecules of a drug can slip through the tears before they heal in 8-12 hours.
posted by Kevin Street at 2:47 AM on November 11, 2015 [3 favorites]

I got course of preemptive chemotherapy for potential metastasis in my brain in parallel with the ordinary chemo for my lymphoma. It was injected intrathecally (into the spinal fluid, between vertebrae) due to the above transport problems over the blood-brain barrier. It was both one of the most painful experiences of my life and horrifying. I would have actual nightmares about it. Hopefully this won't be as common in the future.
posted by groda at 3:58 AM on November 11, 2015 [6 favorites]

The best part is, after the procedure was completed, it turned out everybody's phone was fully charged.
posted by escabeche at 4:45 AM on November 11, 2015 [13 favorites]

Holy crap, you go science. For me this is up there with stuff like "using a virus shell to deliver medicine" and "growing an ear on a mouse's back" level of wow.
posted by Theta States at 7:01 AM on November 11, 2015 [4 favorites]

"Literal Breakthrough"
posted by shenkerism at 7:55 AM on November 11, 2015 [3 favorites]

This technology is a plot point in the podcast The Message. http://www.metafilter.com/154150/The-Message
posted by Obscure Reference at 10:57 AM on November 11, 2015 [1 favorite]

"Literal Breakthrough"

By doctor Nomen Omen Fingers Crossed!

(But seriously, this is absolutely fascinating. Sometimes I really love living in the future.)
posted by hat_eater at 12:21 PM on November 11, 2015

But seriously that inventor who wants to charge cellphones with this technology? Then someone mentioned it is probably weapons research, and here it is. A minute dose, barely detectable, driven straight to the brain, by passing a doorway, or a machine passing overhead.

However one of the brighter things science came up with is, chemo before surgery to curtail metastases from breach of the cancer. What with the yeast that makes opiates and this and that, I might make a tinfoil/copper hat.
posted by Oyéah at 1:01 PM on November 11, 2015

Obscure Reference, I came here to point out the same thing. And, as Insightec was founded by GE Health, The Message is starting to seem like it was greenlit by Jack Donaghy.
posted by MarchHare at 4:52 AM on November 15, 2015