Tuesday, November 20, 2007

Another big hurdle.

Two research groups form human embryonic human stem cells from somatic tissues.

The actual data can be found here and here.

Woooo boy. This is potentially a big jackpot for science, as it would have a twofold effect. One, the techniques described are fairly simple where any cell lab with tissue culture facilities could likely generate these lines. Two, it would probably get the religiously outraged off the backs of scientists as well. I say probably because it's unclear whether a embryonic-like stem cell line still qualifies as life in need of protection, considering the bizarre demarcations they currently use are rather arbitrary.

A couple observations.

First, both techniques use an ecotropic retrovirus, which is probably completely out of the question for therapeutic use. There's nothing to inactivate this in the system described. Perhaps more of a concern is the cocktail of genes used, where both labs use a pair of oncogenes, or cancer-promoters. Naturally these kind of genes encourage the kind of proliferation you see in stem cells, but it clearly could pose a more immediate danger in the body.

More importantly, while these findings are very exciting, it remains to be seen how viable they are in the pursuit of stem cell therapies, which is the endgame scenario for this research. Until the process is entirely vetted it should not be hailed as some singular panacea to the controversial debate, and is likely to generate new problems that were out of reach previously.

Friday, November 09, 2007

When one of my cultures die, I die a little inside, too.

Scientists construct a stem cell scaffold from seaweed products.

Now, as compared to yesterday's antics, this kind of technology is taking a credible step towards legitimate therapeutic applications. Stem cells in culture are notoriously picky; they typically like to be fed only from one side, need to have their media changed routinely and need to be grown on special membrane substrates. Ostensibly, this presents a problem in the body, where such furnishings are unlikely to be found. An inert scaffold presents its own problems - what happens when you need to take the construction equipment out after everything has grown over?

Ashton, created the device from a material known as alginate. Alginate is a complex carbohydrate found naturally in brown seaweed. When mixed with calcium, alginate gels into a rigid, three-dimensional mesh.

This is a real clever synergy of biochemistry, materials science and engineering. I'd call it the great grandson of the modern disposable diaper, another life saving invention.

Thursday, November 08, 2007


Hey, Ladies.

Are you worried your monthly miracle is going down the drain? Literally? C'elle to the resuce! For a mere $1500 a year this company will take your glorious discharge and all its potential stem cells and keep it nice and safe in the event you might want it back, to, uh....well really, there's nothing you can do with it right now.

Honestly, this venture is long on optimism and short on evidence. Their product is hope, not an actual scientific technique.

But let's not be too hasty, as Dave Foley from the Kids in the Hall once said...

Cause after all, what is it? a cluster of blood vessels, awaiting a fertilized egg. Providing a safe warm place for that egg to grow. And if a life does not occur, the whole thing is flushed away, and the cycle begins again. Now is that anything to be ashamed of or disgusted by? No, this is the nesting stuff of humanity!

That's why the woman I shall love will be able to menstruate as fully and freely as she desires. Even if her monthly flow should build in intensity to a raging rust colored torrent! An unbridled river of life giving blood flowing from between her legs! An awesome cataract plunging off the edge of our couch. I wouldn't be fazed! No, no, even if coureur de bois would come up stream, battling the rapids, and singing a 'jaunty song'! I would take no offense, rather I would ford across that mighty womanly river, and fetch herbal tea and Pamprin. And then I would mop her brow and admire her fecundity. For I...Have A Good Attitude....Towards MENSTRUATION!

Wednesday, November 07, 2007

Taste the Brainbow

Stem cells may secret brain repair substance. What happens when you take a deficient rodent brain and inject it with stem cells? Brain rescue, at least in Alzheimer's-like mice models. This is a more elaborate variation on seminal work from last year.

Rather, the group speculates that the transplanted cells secreted protective neurotrophins, proteins that promote cell survival by keeping neurons from inducing apoptosis (programmed cell death).

What's interesting here is how malleable the system is. The brain is no different than the muscle or the skin in that it can respond to simple biochemical stimuli. Hook and levers, people, hooks and levers.

LaFerla's team genetically engineered mice to lose cells in their hippocampus, a region in the forebrain important for short-term memory formation. These mice were about twice as likely than unaltered rodents to fail a test of their ability to discern whether an object in a cage had been moved since their previous visit.

It would be interesting to see what kind of effect this model would have on the amygdala, the repository of emotional responses and almost always the first target of dementia diseases like Alzheimer's. However, I suppose it is difficult to tell if a mouse if more or less sad than the day before, and they aren't too forthright with that information.

The next step is to isolate this neurotrophin and throw it into a series of in vitro models, see what kinds of things pop up. A little combinatorial chemistry could begin to define what molecular appendage is the business end.

The chances of succumbing to a dementia like Alzheimer's has risen from about 1 in 6 to over 1 in 5 with our slowly creeping increase in life expectancy. With a tsunami of Baby Boomers turning 60, a sense of urgency is likely going to flock towards work of this nature very soon.