

Scientists Make Mice Immune to Radiation - miles
http://www.dotmed.com/news/story/10571/

======
Udo
As has become standard in science articles, this one too is highly
sensationalistic and potentially misleading.

NO is, in low doses, a signaling molecule used by the body to facilitate
intercellular communication. Similarly to ischemic attacks (as in strokes),
what follows acute radiation exposure is a massive disruption of normal cell
operations. There are, to use a bit of programmer lingo here, "checksums" in
place to detect these kinds of disruptions and to shut down affected cells
immediately. This is essentially like a segmentation fault or any other kind
of fatal exception, and it's called apoptosis.

During normal conditions, apoptosis signaling pathways are essential to weed
out cells that aren't functioning properly. During massive crisis, however,
this mechanism kills people, because it is suddenly triggered in a large
amount of cells. That's what kills stroke and heart attack victims (if they
survive the incident itself). The body simply doesn't know that in this case
it would be life-saving if it kept corrupted cells alive.

A similar thing happens with acute radiation poisoning: cells die en masse,
usually the mucosae are affected the worst, leading to massive shock and
internal bleeding. This particular research apparently focuses on halting
these apoptosis pathways, so the body doesn't self destruct.

Yes, that's essential. However, there is a price to pay that the article
almost completely ignores. While interfering with the cell death signal saves
you from immediate death, it does nothing to repair damaged porteins and DNA.

~~~
miles
As has become standard in strongly-upvoted HN posts, this one too is highly
sensationalistic and potentially misleading.

I am genuinely sorry to be so snarky, but I am _really_ tired of scientific-
sounding arguments (like the "Why I am not worried about Japan’s nuclear
reactors" article) being automatically credited on this site.

 _"While interfering with the cell death signal saves you from immediate
death, it does nothing to repair damaged porteins and DNA."_

Did you bother to read the second page?

"Also, a bigger mystery is figuring out how, by blocking this pathway, cells
are able to fix the damaged DNA within. Dr. Isenberg says they know that
following radiation exposure, the DNA is scrambled, but somehow, with this
treatment, the cells are able to get themselves right."

"'It's not that we're blocking radiation from hitting the tissue,' he says.
'Somehow...they repair themselves, and go about their business.'"

~~~
Udo
The article flat-out lies about achieving radiation immunity. Claims like
these are extremely representative examples of misleading sensationalism.
There is simply no room for discussion about the central point: the article is
making statements that are provably wrong. After that come the smaller claims
they make, several of which sound highly dubious to me, especially your
favorite one here:

> _"'It's not that we're blocking radiation from hitting the tissue,' he says.
> 'Somehow...they repair themselves, and go about their business.'"_

I strongly suspect there is no data to support this statement. We have known
about small-scale repairs for a few years now, but this statement goes far
beyond that. With the radiation doses involved, this phenomenon would require
the reconstruction of information that is quite simply lost from the genome.
Of course it is possible that many of these cells "go about their business",
but that's not the same as assuming they have somehow repaired themselves.

As far as being " _automatically credited on this site_ " I think you should
give the other users a little more credit, and perhaps tone down your blanket
judgements a little at the same time. Just because I made a few " _scientific-
sounding arguments_ " doesn't mean I'm automatically wrong. The article claims
immunity from radiation which is total gibberish. As far as the alleged
complete self-repair goes, there are plenty of reasons to be extremely weary
about this as well.

By the way, I think I made it clear in the original post how important
research like this is. At the same time I believe it's even more important not
to misrepresent findings.

------
miles
FTA: _In mice, when Dr. Isenberg and his team introduced a drug that prevented
a protein, thrombospondin-1, from binding to a surface cell receptor called
CD47, the animals could endure almost unheard-of doses of radiation with
virtually no ill effects._

This is from late 2009. Does anyone have an update on this research? Would
obviously be a great boon if it was equally effective in humans.

~~~
biot
It would be ironic if this therapy causes increased risk of cancer, for which
chemotherapy then has little effect. Then again, if the resistance is
temporary I imagine some workers in Fukushima might benefit from this once
it's been demonstrated safe enough.

~~~
kajecounterhack
Go to the second page

"Perhaps equally exciting, Dr. Isenberg and his team found that while his
technique protected healthy cells from damage, it actually increased the
effectiveness of radiation treatments on cancer cells."

~~~
bedris
This could also be due to the fact that CD47 blockade allows preferential
phagocytosis of cancer cells by macrophages [1,2] so it might not be solely
radiation sensitivity that is leading to the clearance of the tumor cells.

[1] <http://www.ncbi.nlm.nih.gov/pubmed/19632179>

[2] <http://www.ncbi.nlm.nih.gov/pubmed/19632178>

------
possibilistic
I don't really buy this. There's simply no way that messing with the NO
pathway can prevent DNA degradation resulting from radiation exposure. I'm not
familiar with irradiation units and how they correlate to DNA damage, but all
amounts are harmful to the molecule. Ionizing radiation damage can be fixed
via repair pathways, but it's simply a function of probability as to when this
machinery fails in a critical location.

The paper might be interesting to read, though, especially if it got cited. As
always, news articles tend to inflate claims and miss the point entirely.

~~~
Joakal
Look to nature surviving so well in Chernobyl?

~~~
smackay
Nature is doing so well around Chernobyl because of the lack of humans. I
don't have a reference to hand but I beleive that the birds in the area have a
high rate of genetic defects and low reproductive success. That fact that the
environment seems to be doing well is a statement of how much impact humans
have on their surroundings.

~~~
copper
Yes, I remember that one: [http://www.physorg.com/news/2011-02-chernobyl-
birds-smaller-...](http://www.physorg.com/news/2011-02-chernobyl-birds-
smaller-brains.html)

Rereading it, it seems that the effects seen on the birds are seen in humans
too, but at higher contamination levels.

------
bedris
Here is the original Sci Transl Med (2008) paper:
[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2811586/?tool=pu...](http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2811586/?tool=pubmed)

And here is a follow-up paper in Am J Pathol (2008):
[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2543077/?tool=pu...](http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2543077/?tool=pubmed)

Both are freely available at the links provided.

------
Tichy
How am I supposed to mutate into a superhero if radiation has no effect?

~~~
reitzensteinm
I know you're joking, but from what Udo is saying, it seems like this is
stopping the body from killing off corrupted cells. So if anything, this would
actually be a step closer to super hero mutation.

~~~
flipbrad
Not really. It's a step closer to randomly dispersed neoplasia/tumours popping
up around your body!

step closer to have super hero mutant children, perhaps, if it's keeping your
gonads alive but mutant.

~~~
reitzensteinm
Well, to be fair, a step closer doesn't mean it's not still basically
impossible... but you're right, children are a far more likely vector.

------
masklinn
So coppelions are real?

