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Latest Wall Street Journal
column is on how anti-virals outwit natural selection:
Draco, who wrote Athens's first constitution in about 620 B.C.,
decreed that just about every crime should be punishable by death,
because that was what petty criminals deserved and he could think
of no harsher penalty for serious criminals. "Draconian" means
indiscriminate as well as harsh.
So it is appropriate that the word "Draco" has been appropriated
by the inventor of the first antiviral treatment that promises to
work against all viruses. Until now, if antivirals worked at all,
they were specific to particular viruses or even strains of virus:
protease inhibitors for HIV, Tamiflu for some forms of flu and, of
course, particular vaccines to prevent particular viral
John S. Dykes
In this context, Draco stands for Double-stranded RNA Activated
Caspase Oligomeriser. The "Dra" bit refers to a telltale sign of
viral infection-double-stranded RNA molecules-while the "co" bit
concerns the mechanism by which a cell commits suicide if so
infected. In the lab,writes its inventor, Todd Rider of MIT's
Lincoln Laboratory, "we have demonstrated that Dracos are effective
against viruses with DNA, dsRNA, positive-sense ssRNA, and
negative-sense ssRNA genomes; enveloped and nonenveloped viruses;
viruses that replicate in the cytoplasm and viruses that replicate
in the nucleus; human, bat and rodent viruses; and viruses that use
a variety of cellular receptors."
In other words, at the lab bench, just about any virus will get
the death sentence from Draco-from the petty rhinovirus that causes
the common cold to the homicidal dengue fever. That's draconian.
Moreover, it does not just seem to work in cells in a petri dish:
In live mice infected with H1N1 influenza, Draco cured the animals.
It sounds very promising, though there is much safety and efficacy
testing to go before it can be given to patients.
Given that Dr. Rider's Draco combines some of our existing
molecular tricks in a new configuration, it raises a question that
often nags at me when miracle cures are discovered within the body
itself: If it works so well, why didn't evolution equip our cells
with it as a defense against disease? Interferon, for instance, was
hailed as a cancer cure two decades ago, though in due course it
Those cures that do not disappoint, like antibiotics, are
foreign to our cells' metabolism. Penicillin was the special
bacterium-killing invention of a fungus, so we had to wait until
Alexander Fleming left the laboratory window open in 1928 before we
could borrow it as a medicine.
What is new in Dr. Rider's approach is to link the "Dra" to the
"co." Why did natural selection not think of that itself in some
I don't know the answer. Most of the viruses that cause serious
disease disable our native defense mechanisms. They may target the
double-strand recognition system or the cell-suicide pathway (or
both). A virus usually keeps a cell from killing itself by
interfering with the start of the chain of cause and effect that
leads to suicide, whereas Dr. Rider has used a later link to keep
that mechanism on-a link that viruses mostly do not attack.
Most likely, the evolutionary explanation for Dr. Rider's
ability to do better than Mother Nature is that there is no way to
get there from here. Inside the normal cell, the "Dra" bit is just
so separate and different from the "co" bit that no accidental
mutation has ever put them together.