| ARMY STUDIES DNA
"GENE GUN" FOR VACCINE DELIVERY
"This is important when rapid vaccine
development is needed for a newly emerging disease threat or
possibly for a genetically engineered biological warfare
pathogen."
NOTE from Larry Scott, VA
Watchdog dot Org ... Haven't we been here before? This
sounds like a re-do of the vaccine injector guns that so many of
us had pressed against our arms years ago. Use our search
engine for more about
USAMRIID.
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Army studies DNA vaccine delivery system
By Lt.
Jennifer Cragg
Special to American Forces Press Service
WASHINGTON, D.C. - Army scientists are studying a new DNA vaccine
delivery method that will one day be needle-free and painless, a
senior Army research scientist at Fort Detrick, Md., said.
"DNA offers a number of advantages over conventional vaccine
approaches, especially with regard to biodefense vaccines," Connie
Schmaljohn, senior research scientist at the U.S. Army Medical
Research Institute of Infectious Diseases, told "Armed with
Science: Research and Applications for the Modern Military"
listeners during a May 27 audio webcast.
"This is important when rapid vaccine development is needed for a
newly emerging disease threat or possibly for a genetically
engineered biological warfare pathogen," added Schmaljohn, who
holds a doctorate in virology.
One of the newest DNA vaccine delivery methods relies on
technology known as the "gene gun," which is capable of delivering
the vaccine directly into cells. The needle-free vaccination
method is more cost-effective and less painful for the recipient.
"The
DNA is first coated onto very, very tiny gold beads, and those
gold beads with the DNA are then put inside of a plastic device
that's about the size of a small flashlight," she explained.
"Inside that device is also a little canister of compressed helium
gas. When the trigger of the gene gun device is pushed, the gas is
released and it propels the gold coated with the DNA out of the
device into the skin of the vaccine recipient."
USAMRIID is conducting a human study of DNA vaccines using this
delivery method. Schmaljohn's research team has isolated small
amounts of DNA from the Hantaan and Puumala viruses - known health
threats to U.S. troops stationed in Europe and Asia - to develop
the vaccines. Both vaccines are in Phase I clinical testing, the
first step toward licensure by the U.S. Food and Drug
Administration.
"Its main goal is actually to prove that the vaccine is safe in
humans, but of course, we're also interested in determining if
it's inducing an immune response," she added.
"The hantaviruses, once they infect humans, can cause one of two
serious human illnesses: hemorrhagic fever with renal syndrome,
which occurs in Asia and Europe, or hantavirus pulmonary syndrome,
which occurs in the Americas," Schmaljohn said.
USAMRIID is producing a DNA vaccine for the Asian and European
hantaviruses that can cause hemorrhagic fever with renal syndrome.
This disease first was recognized as a threat during the Korean
War.
"Today there's more than 100,000 cases of hemorrhagic fever with
renal syndrome each year, with the highest number occurring in
China, Russia ... Scandinavia and other parts of Europe,"
Schmaljohn said.
These viruses are found in many types of rodents, including rats,
field mice and meadow voles.
"They're transmitted to humans in the aerosols of rodent's urine,
feces and saliva," Schmaljohn explained. "The rodents that carry
these viruses are persistently infected, and they show no signs of
illness."
She added that over tens of thousands of years, these viruses and
rodents have formed a mutually exclusive relationship in which
both have adapted to one another. While the virus doesn't appear
to affect the rodents' health, the virus does pose significant
risk to humans.
Schmaljohn reminded "Armed with Science" listeners about the
importance of medical research to the health and well being of the
nation.
"Without continuously pushing the envelope of science, we will not
be able to adequately respond to new disease threats," she said.
Editor's note: Navy Lt. Jennifer Cragg serves in the Defense Media
Activity's Emerging Media Directorate.
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TOPICS:
veterans, veterans' benefits, VA, Department of Veterans' Affairs,
DNA, gene gun, vaccine, USAMRIID |