People with cystic fibrosis are prone to lung infections with Pseudomonas aeruginosa, making a vaccine against the germ an attractive prospect. There isn’t a human vaccine yet, but there maybe soon.

In mice, a vaccine made up of outer proteins from P. aeruginosa fused to viral proteins induced an immune response and protected the animals against fatal infections with the bacteria, report Dr. Ronald G. Crystal, at Cornell University in New York, and colleagues there and at GenVec Inc., in Bethesda, Maryland.

Mice immunized with the vaccine developed immune cells that specifically targeted the Pseudomonas protein.

Repeated immunization with the vaccine boosted the response further, according to the researchers’ article in the Journal of Clinical Investigation.

While unvaccinated mice died within three days of a normally lethal challenge with P. aeruginosa, 80 percent of immunized mice survived for more than two weeks.

Crystal’s group suggests that their vaccine strategy might work for other organisms, too.

SOURCE: Journal of Clinical Investigation, online April 1, 2005.