Laboratory researchers have developed a new way to cripple a virulent class of microbes that have become increasingly resistant to antibiotics and continue to kill hundreds of thousands of hospital patients every year. The discovery, based on experiments with laboratory mice, provides immunization against the Pseudomonas aeruginosa bacterium, suggesting a fresh alternative to antibiotics in the fight against the microbes responsible for most hospital-acquired pneumonia deaths. The bacteria kill half the hospital patients they infect.
The new finding led by scientists at the University of California San Francisco and the Medical College of Wisconsin is reported in the April issue of Nature Medicine. A commentary on the research and its significance appears in the same issue.
Nationally, more than two billion dollars a year are spent combating hospital pneumonia, a condition most often contracted by patients already under intensive care.
The Pseudomonas species targeted in the research is also responsible for the untreatable lung inflammations which devastate the lives of half a million people with cystic fibrosis. In addition, it belongs to the same group of gram-negative bacteria as E. coli, Salmonella, and the microbe responsible for plague, all of which may be candidates for the same immunization strategy developed by the scientific team.
"All these species utilize the same combination of proteins to deliver deadly toxins to host cells," says Jeanine Wiener-Kronish, MD, professor of anesthesiology and medicine UC San Francisco and one of the senior authors on the Nature Medicine paper. "We have developed an antibody against one of these proteins and shown that it blocks Pseudomonas from injecting toxins into lung cells. This antibody may well provide immunization against these other bacteria species too."
Senior author on the Nature Medicine paper is Dara W. Frank, PhD, professor of
microbiology and molecular genetics at the Medical Coll
Contact: Wallace Ravven
University of California - San Francisco