Extracellular toxins of Pseudomonas aeruginosa. III. Radioimmunoassay for detection of alkaline protease.

A sensitive and specific solid phase radioimmunoassay (RIA) for detection of the alkaline protease (AP) of Pseudomonas aeruginosa (PA) was developed and the RIA was used to assay 10 PA strains of various origin and serotype. A great strain variability of AP production was found which differed from 180 to 0.1 microgram per ml of culture supernatant fluid (CSF). The AP concentrations were compared to the total proteolytic activity of the CSF and the results were discussed in relation to cystic fibrosis patients suffering from chronical PA lung infections.