Human Brain Cells Are Grown In Mice

By injecting human embryonic stem cells into the brains of fetal mice inside the womb, scientists in California have created living mice with working human brain cells inside their skulls.

The research offers the first proof that human embryonic stem cells -- vaunted for their potential to turn into every kind of human cell, at least in laboratory dishes -- can become functional human brain cells inside a living animal, reaching out to make connections with surrounding brain cells.

The human cells had no apparent impact on the animals' behavior. About 100,000 cells were injected into each animal and just a fraction survived in their new hosts. That means the animals' brains were still more than 99 percent mouse -- a precaution that helped avoid ethical objections to creating animals that were "too human."

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"Let's say you're in the last stages of research before testing a new drug in humans," said lead researcher Fred Gage of the Salk Institute for Biological Sciences in La Jolla, Calif. "This could help tell you what effect it will have on human neurons inside a brain."



http://www.washingtonpost.com/wp-dyn/content/article/2005/12/12/AR2005121201388.html

Bill Oreilly could increase his IQ.

Then George W. Bush could increase his.

That's right. He'd say, "I want steak."

...it would figure out how to open the fridge himself. Mine already did. She helped herself to a whole chicken one night a few weeks back. Now we have to keep a cinder block in front of the refrigerator door...

FEAR the day when dogs figure out the secret of 'doors'!

brain cells went. :)

brain cells went. :)

Hahahahahaha.... very good.

Seriously though.."no apparent impact" is a pretty mushy statement. The vast array of available behavioral, emotional and psychological changes aren't very "observable" in people, never mind mice.

(The mice will probably begin their campaign by falsifying the results of tests of lab mice.)

about this statement:
"Let's say you're in the last stages of research before testing a new drug in humans," said lead researcher Fred Gage of the Salk Institute for Biological Sciences in La Jolla, Calif. "This could help tell you what effect it will have on human neurons inside a brain."

Will it? Or will it tell you only what effect the drug will have on human neurons inside a mouse's brain. How do they know that the results of these sorts of experiments are generalizable to humans, even though it's human brain cells they will test? In other words, would the condition of being a human brain cell, but located in a mouse's brain, be substantially different than that of being a human brain cell within a human brain, and so the effects of the drug in question upon those human brain cells within a mouse's brain might not be applicable to humans? Wouldn't there be, for instance, brain chemicals present, unique to mice, operating on the human brain cells within the mouse brain, that could skew the results? Such an intervening variable could really be a problem for these studies, it seems to me.

The cells migrated into the forebrain, where they grew only to the size of mouse neurons. Most extraordinary, Gage said, was that they connected to others and were firing -- though it is still unclear if they fire in electrical patterns typical of mouse or human cells.

So, are those cells really human anymore, if they appear to be taking on the characteristics of mouse brain cells?

This isn't a critcism of the idea of stem cell research, which in theory I support. I've just never read some of the details, and these questions do arise. Does anyone else know if these issues have already been addressed by the scientists?

Won't it be too big?

It's interesting that the cells migrated to the front part of the brain - isn't the frontal cortex of humans where all the higher reasoning happens?