Common protective antigen (OEP) of Pseudomonas aeruginosa.

Prior immunization of mice with the protein moiety of the endotoxin (OEP) of Pseudomonas aeruginosa isolated by Homma and his associates [1, 2], can protect mice against infection with any of 21 standard strains belonging to Fisher's immunotypes and Homma's serotypes. It is also confirmed that there is found a significant protection in mice each injected with 0.1 ml of anti-OEP rabbit serum against challenge with each of 7 strains of Fisher's immunotypes. It has been revealed through the OEP-HA, agar gel diffusion and indirect fluorescent antibody tests that OEP is an antigen existing serologically in common in P. aeruginosa.