Evaluation of a new polyvalent Pseudomonas vaccine in respiratory infections

Abstract

A new polyvalent cell wall extract, P. aeruginosa vaccine (PEV-01), was evaluated by using a guinea pig model of experimental Psedomonas pneumonia. Guinea pigs routinely developed 4-fold rises in serum hemagglutinating Pseudomonas antibodies after 4 vaccine injections given over 2 wk. Vaccinated animals survived an intratracheal Pseudomonas challenge (1 .times. 108 colony-forming units) significantly better (13 of 14 survived) than did a control group (5 of 14 survived) (P < 0.01). Clearance of viable Pseudomonas from lung tissue was significantly better in vaccinees than controls at 3 h (P < 0.02) and 6 h (P < 0.05) after infection. Gross and histological examinations of lung tissue revealed less pulmonary tissue damage in vaccinated aniamls following Pseudomonas infection. PEV-01 Pseudomonas vaccine appears capable of eliciting a specific protective response in the guinea pig respiratory tract.