invisible-man

When sitting around drinking late at night, the conversation inevitably turns to superpowers and which one everyone wants.

Aside from a super healing factor and flight, one of the top picks is surely invisibility–though usually for some pretty diabolical reasons, like stealing your neighbor’s newspaper.

While we’re still not quite at the level of full-on invisibility cloaks, scientists have developed a way to make cells transparent! Invisible Woman this isn’t, but maybe it’s enough to sneak a midnight snack?

(Warning: some images may not be for the squeamish.)

Probably not even that, but researchers at the Riken Center for Developmental Biology were able to make a mouse’s brain transparent enough to use two-photon excitation microscopy and confocal laser scanning microscopy. They were able to get detailed images of individual corpus callosum—the neural fibers that connect the left and right hemispheres of the brain.

  • How they did it

Using fructose found in honey and fruit, along with some water and dashes of other ingredients, researchers created “SeeDB,” short for See Deep Brain, which turns cells transparent. More importantly, it does not cause serious damage to the cells or cause swelling. Basically, it leaves the cells pretty much as they are—but transparent! It takes about three days for the reagent to work. Afterwards, cells look like this:

▼From top to bottom: Mouse embryo, neonatal mouse, adult mouse brain

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  • Why they did it

For many of us, this probably seems like a big “so what?” It’s not really effective for invisibility (unless you’re only 6 mm thick), so why would we want this? Well, while the average person probably doesn’t have access to all that fancy microscopy equipment, transparency of cells helps out researchers who DO have access to it.

▼Video of 6mm of mouse’s brain, using continuous optical tomography

▼Video of a 3-D cross section of 6mm of a mouse’s brain, taken with two-photon excitation microscopy

Apparently, and I’m going to have to take their word on this, current microscopy only allows scientists to see about 100 micrometers into living cells. Obviously, this isn’t going to let you really “peer into the mind” of anything. By making cells transparent, they’re able to get images of up to 6 mm! Which is an improvement of 600 percent in case you’ve forgotten how many micrometers are in a millimeter. (It’s 1,000, according to the Internet. Because I had no idea.)

▼Two-photon excitation microscopy with a custom made lenses and a cross section of the 6 mm scanned

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Using this technique, scientists are able to capture images of brains in action, helping map out neural path ways and letting them take closer looks at stuff like the olfactory bulb. Who knows what this information could lead to! Cologne that doesn’t smell like giraffe farts would be nice…

  • What’s next

This isn’t just for brains though. The scientists were even able to turn a mouse embryo almost completely invisible (as you saw above). I assume that this is for research purposes, since it would allow them to inject tracers and watch directly how the body develops, and not for more nefarious designs. Like training invisible mouse ninjas. (Or maybe both!?)

▼Left image is of the olfactory bulb mitral cell dendrite from the side, middle image is also of the olfactory bulb mitral cell dendrite from the top, and the right image is of olfactory nerve axons.

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But there’s still a lot of work to be done with the old noggin’. The researchers who developed SeeDB believe that this will be useful for analyzing and developing connectomes (basically brain maps) in addition to helping us better understand developmental biology and developing “3-D biology.”

Okay, that last one sounds like something James Cameron dreamt up while sea sick and puking into the ocean.

Source: Riken Center for Developmental Biology (detailed paper, press release)