The role of the elastase of Pseudomonas aeruginosa in experimental infection

Abstract

The characteristic vascular lesion described in human systemic infections due to P. aeruginosa has been experimentally produced in mice infected with this microorganism. Since a prominent microscopic finding in the experimental vascular lesions is the destruction of the elastic laminae, the elastase produced by the same pathogenic strain of P. aeruginosa was assayed against elastin in vitro. The in vitro studies indicate that the enzymatic activity is near its optimum at physiologic pH and temperature, and activity is only slightly inhibited by normal human serum. Sera from patients with extensive burns, some infected with P. aeruginosa, and from `vaccinated' human subjects all contained low levels of serum elastase inhibitor similar to normal persons.