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By Andrew Pollack
An oily mixture resembling salad dressing
that can blow up anthrax bacteria. A toxin detector made of
a slice of living rat brain on an electronic chip. A drug
that would kill all bacteria and another that would boost
a person's immune system to withstand any pathogen.
These are all ideas, some far off and
some surprisingly close at hand, that are being pursued in
what could become the nation's newest medical battle -- the
war against bioterrorism.
Since Sept. 11, the government has been
stepping up efforts to improve the nation's ability to respond
to a germ attack. Much of the focus has been on improving
the public health system's ability to spot an outbreak, quarantine
the infected and deliver medicines. Another focus has been
to accelerate production of vaccines for anthrax and smallpox.
But experts say it is also
necessary to develop much better technology to
detect, diagnose and treat biological agents. That is partly
because there are dozens of pathogens that might conceivably
be used in an attack, including some unnatural ones made by
genetic engineering, and it would be impractical to develop
vaccines for all of them.
A Pentagon advisory panel estimated it
would cost up to $3.2 billion to develop just eight vaccines.
So new approaches beyond vaccines are needed that can address
a wide range of possible agents.
"How do we deal not only with the
known and anticipated threats like anthrax, but also the ones
we haven't thought of?" said Dr. Stephen S. Morse, director
of the Center for Public Health Preparedness at Columbia University
and formerly manager of a Defense Department germ defense
research program. He said the approach of making vaccines
for individual pathogens "is needed, it has value, but
it's not sufficient for where we want to be in the future."
Dr. Andrea Branch, an associate professor
at Mount Sinai School of Medicine who has advised the Pentagon
on responding to germ warfare, said public health measures
might prevent an infection from spreading, but new medicines
are needed to treat those already infected.
Even before Sept. 11, dozens of biotechnology
companies and academic laboratories were working on projects
financed by the Pentagon or other government agencies to develop
new bio-defense techniques. Now, some of those doing such
work say they being urged
to speed up the pace, but also not to talk about
their work so much.
The new battle will be fought with the
tools of biotechnology, genomics and immunology. The genomes
of microbes can now be sequenced in a matter of weeks, giving
new insights into their structure. In the last two weeks one
group of scientists at Harvard Medical School reported finding
a gene variation that makes mice resistant to anthrax, and
another group said it had designed a molecule that protected
rats against normally lethal doses of anthrax toxin.
Indeed, unlike some other areas of defense-related
research, bio-defense work will have numerous civilian spinoffs,
since doctors must respond to new pathogens that arise naturally,
like H.I.V. and West Nile virus.
"The war's been on for as long as
people have been on this earth," said Dr. David A. Relman,
associate professor of medicine at Stanford. "It didn't
start on Sept. 11."
Dr. Relman is working on ways to identify
the pathogens in a biological attack. "These are products
that are going to be used by every clinician in the world,"
he said, "whereas detectors for sarin nerve gas are not
going to be used by your routine public health function."
Spurring much of the research has been
the Defense Advanced Research Projects Agency, or Darpa, the
Pentagon's central research organization. The agency spent
$166.8 million on biological defense research in the fiscal
year that ended last month. The work is mainly aimed at protecting
soldiers, though the same techniques could help civilians.
Other parts of the Defense Department
have their own research programs, as do other agencies. The
National Institutes of Health spent about $49.7
million on research for bio-defense last fiscal
year, the Centers for Disease Control and Prevention $46.6
million and the Department of Energy, which runs national
laboratories, $39.6 million, according to a report issued
last month by the General Accounting Office. All those figures
seem likely to grow in response to the Sept. 11 attacks.
Darpa prides itself on doing long- range,
highly innovative research that often fails but can have a
huge impact if it succeeds. It was Darpa research that eventually
led to development of the Internet and stealth aircraft. An
agency spokeswoman said no interviews on bioterrorism were
being given. But outsiders and the agency's own Web site paint
a picture of a wide range of projects, some fairly bizarre.
"There are times I say, `There's
no way this is going to work,' " said Dr. Carol Shoshkes
Reiss, a professor of biology at New York University who advises
Darpa. But some of the programs have made good progress, she
said.
Among the most unusual projects is one
at the University of Montana to train bees to sniff out chemical
or biological agents. Dr. Michel Baudry, a professor of biological
sciences at the University of Southern California, is trying
to build a sensor by putting a slice of rat brain on top of
an electronic chip that can sense the brain tissue's reaction
when exposed to a harmful substance. This is the high-tech
equivalent of the canary in the coal mine.
The Department of Energy has also been
working on biological and chemical agent sensors that might
monitor the air in public places. A major challenge is to
avoid false alarms, which would cause needless evacuations,
disruptions and panic. A monitor that continuously sniffs
the air for biological agents might take 100 million measurements
a year, and even one or two false alarms might be unacceptable,
the Energy Department says.
But sensing an infectious agent or toxin
is just the first step.
There must also be ways to determine
if people are infected and to identify the pathogen involved
-- and to do it quickly. Many germs produce symptoms similar
to the flu, making it hard
to tell there has been an attack. Moreover, in
some cases, by the time the symptoms appear, the infection
has spread and those infected are beyond treatment.
Cepheid, a biotechnology company in Sunnyvale,
Calif., hopes to supply the Army with prototypes of a device
that can do a genetic test for a pathogen in 30 minutes, compared
with the hours or days it now takes.
But some bugs do not immediately go into
the blood or other bodily fluids that can be easily sampled.
"In the body the bugs have to amplify
to a certain level before you can detect them," said
Dr. C. Richard Lyons, an associate professor of medicine at
the University of New Mexico Health Sciences Center in Albuquerque.
"It may be too late at that point."
Dr. Lyons said a quicker approach might
be to analyze an infected person's response to the pathogen
rather than try to isolate the bug itself. The levels of various
proteins in the blood, which could be measured in minutes,
might be different for different types of pathogens, he said.
Dr. Relman at Stanford hopes to identify
which genes in human cells are turned on or off in response
to exposure to different agents. "We do know that gene
expression patterns change very quickly in response to an
infection," he said.
Other projects aim at preventing
infections or treating them once they occur. Dr.
James R. Baker Jr. at the University of Michigan has developed
what he and colleagues jokingly refer to as a salad dressing
that can kill many types of microbes, including hardy anthrax
spores.
They say the disinfectant concoction,
made of microscopic droplets of soybean oil suspended in water,
is safe enough to apply to the skin or to equipment, to spray
into the nose to stave off infection and even drink in small
quantities.
Dr. Baker explained that when some regular
salad dressings are shaken, bubbles of oil get dispersed in
the water. Those bubbles contain energy from the shaking,
which is stored as surface tension. This energy is released
when the oil droplets coalesce again.
Dr. Baker's disinfectant has extremely
tiny bubbles, about 200 billionths of a meter across, which
have extremely high energy but are prevented from coalescing
by detergent. "But a bacterium is like a big oil droplet
and they coalesce with it and blow it up," he said.
Ted Annis, chief executive of NanoBio,
a company set up to sell the product, said it could be ready
to use in six months if the company can get $5 million to
complete its testing.
Isis Pharmaceuticals in Carlsbad, Calif.,
is trying to develop drugs that can kill virtually all bacteria.
"There are molecular common denominators of life, and
if we find them and make drugs that bind to them, then it
won't matter what bug is used and how it's been modified,"
said Dr. David J. Ecker, a vice president in charge of the
project.
Dr. Ecker said the company had found stretches
of RNA, a key molecule of life, that are common to all bacteria
and to a wide variety of viruses as well. But he said the
Defense Department would not let him discuss how close the
company is to finding drugs that could disable this RNA. Another
effort is to improve the
human immune system to help a person withstand
all pathogens.
Dr. Arthur M. Krieg, a medical professor
at the University of Iowa and chief scientific officer at
Coley Pharmaceutical Group in Wellesley, Mass., believes that
certain DNA sequences common in bacteria but not in people
are recognized by the human immune system as a sign of infection.
So giving these DNA segments as a drug might put the immune
system on high alert.
Of course, biotechnology can be used not
only for defense but for offense. Terrorists might try to
use genetic engineering to make pathogens resistant to common
antibiotics or vaccines or even to create entirely new pathogens.
So new defenses might always be needed.
"The image I have in my mind was
who was going to develop the bomb first, Germany or the United
States," said Dr. Branch of Mount Sinai. "Now there
is a different kind of race."
New
York Times October 9, 2001
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