Flu Breakthrough: The Search for a Universal Vaccine
Tired of having to get a different flu shot -- or two -- every year? Someday one shot may protect us against all the strains.
The History of the Flu Shot
The 1918 pandemic was particularly vexing to doctors because they had
nothing at their disposal to prevent or treat it. Researchers didn't even
discover the influenza virus until 1933, and a working vaccine wasn't released
until a decade later. Even today, with 21st century medical technology at our
disposal, flu vaccination involves a lot of guesswork and uncertainty.
Researchers from around the world have to look at flu surveillance reports
several months in advance, anticipate which strain will be prevalent in the
coming season, and hope their prediction is correct. They still haven't been
able to create one vaccine that can target all strains for all seasons.
But that might be about to change.
Last spring, Marasco made a huge breakthrough -- he finally hit on the flu
virus's weakness. On the virus's surface sits a lollipop-shaped protein called
hemagglutinin, which enables it to break into human cells and make us sick.
Current flu vaccines trigger the immune system to launch an antibody attack
against the most obvious target on that lollipop -- the big head at the top --
but that head is able to continually change and evade attack. Marasco has
discovered human antibodies that instead target the stalk of the hemagglutinin
protein, which is less likely to change and stays constant in different flu
So far, the antibodies he's discovered have neutralized most flu strains
tested. The next step is to get a drug based on these antibodies into clinical
trials, which could happen as early as 2011, he says. If all goes well,
Marasco's discovery could lead to the very first universal and long-lasting flu
vaccine -- and the end of the seasonal flu shot ritual.
The Search for a Cold Cure
Meanwhile, in a laboratory at the University of Maryland School of Medicine,
medicine and physiology professor Stephen B. Liggett, MD, is trying to crack
the case of another public nuisance: the common cold. Doctors have been trying
to cure this menace for almost as long as people have been getting colds, which
is as far back as anyone can remember.
Trying to understand what makes all of the cold virus strains tick has not
been easy. For Liggett and his research team, it was a meticulous and
time-consuming task to sequence the genome of nearly 100 different strains of
human rhinovirus -- the virus responsible for most colds. Decoding the 7,500
DNA bases that make up each strain is helping them understand the virus's
design, family history, and vulnerabilities.
What Liggett's team has learned is that many cold viruses are related. On
the rhinovirus family tree are about 10 groups of closely related viruses.
That's good news, because it means that antiviral drugs could potentially be
developed to target families of viruses, rather than trying to treat each
individual strain. The bad news is that if two different cold virus strains
infect the same person with a cold, they can swap genetic material to make a
new strain. This means each cold virus has the potential to quickly produce new