Murine interferon-gamma enhances resistance to infection with strains of Pseudomonas aeruginosa in mice.

This study focused on the role of recombinant murine interferon-gamma (rMuIFN-gamma) in modulating resistance to infections produced by Pseudomonas aeruginosa in mice. CBA/C mice were treated with rMuIFN-gamma, exposed to thermal injury, and challenged with P. aeruginosa organisms. Survival of infected, burned mice was determined over a period of 14 days and compared with control animals not receiving rMuIFN-gamma. Two clinical isolates of P. aeruginosa that differed originally in the ability to produce metalloproteases, were used to infect the mice. When the mice were pretreated with rMuIFN-gamma before the infection, no statistically significant differences in survival were observed with either of the two strains of bacteria compared to controls. However, when mice were pretreated and injected therapeutically with rMuIFN-gamma (continued receipt of rMuIFN-gamma after infection), there was a significant protective effect in animals infected with one of the strains of P. aeruginosa. We conclude that rMuIFN-gamma may be useful in treating infections with certain strains of P. aeruginosa in mice.