Active and passive immunization with the Pseudomonas V antigen protects against type III intoxication and lung injury

Pseudomonas aeruginosa is an opportunistic bacterial pathogen that can caus e fatal acute lung infections in critically ill individuals. Damage to the lung epithelium is associated with the expression of toxins that are direct ly injected into eukaryotic cells through a type Ill-mediated secretion and translocation mechanism. Here we show that the P. aeruginosa homolog of th e Yersinia V antigen, PcrV, is involved in the translocation of type III to xins. Vaccination against PcrV ensured the survival of challenged mice and decreased lung inflammation and injury. Antibodies to PcrV inhibited the tr anslocation of type III toxins.