For Linda Cauley, flu season is an annual reminder of the importance of her work. Cauley studies cellular mechanisms that provide protection against influenza and other respiratory infections.
A flu shot - an injection of killed virus - is currently the best way to get protection against the flu, but these vaccines are not perfect, says Cauley, an assistant professor of immunology at the Health Center.
She is working to identify cellular targets for a vaccine that could supplement the current vaccines.
Two types of vaccine are currently used for controlling influenza infections.
The most common vaccine is made from killed virus, which is given by injection; the other contains live, weakened virus that is given as a nasal spray.
"Killed influenza viruses are expensive and slow to produce," says Cauley.
She says there is always some guesswork involved in identifying the appropriate strains to include in the vaccine each year.
Live viruses, on the other hand, may not be appropriate for some patients, including small children and elderly people, who are less able to develop protective anti-bodies.
"What we are trying to do is identify cellular targets for a slightly different vaccine approach," says Cauley.
The strategy involves studying memory cells - CD8 T cells - that help the body defend itself against disease by remembering prior exposure to infectious organisms, such as the flu virus.
"Unfortunately, cellular immunity to viral infections lasts only a few months. An important goal of my lab is to determine why the protective immunity declines so rapidly."
| Linda Cauley, an assistant professor of immunology, is conducting research on cells that help the body protect itself against disease.
|Photo by Peter Morenus
Respiratory viruses like the flu tend to be quick-change artists that rapidly change their outer protein coat, says Cauley.
CD8 T cells, which can 'see' or identify internal viral proteins, seem to be able to provide protection as long as they are in the right place at the right time.
"Our data suggest that protection fails when the cells don't stay in the right place and lose the properties that enable them to kill other infected cells that are virus factories," she says.
"If we can identify the mechanisms that control T cell movements, we may be able to prolong their protective abilities."
The model she and her colleagues are studying has implications for other quick-changing virus infections, such as HIV, says Cauley.
"Our work is in its earliest ages, but our long-term goal is to provide a new vaccine that could supplement the current ones," she says.
"A huge number of people must be vaccinated to prevent a pandemic. A long-lasting vaccine that protects against changing strains would be an extremely useful tool in this battle."