Article
Effects of Pseudomonas aeruginosa elastase on alveolar epithelial permeability in guinea pigs
Infection and Immunity
(1990)
Abstract
Elastase-deficient mutants of Pseudomonas aeruginosa are less virulent than the wild type and are easily
cleared from the lungs of guinea pigs. The effect of P. aeruginosa elastase on lung epithelium, however, is not
yet understood. We addressed the hypothesis that breach of the epithelial barrier by elastase from P.
aeruginosa allows invading organisms and toxic substances to penetrate the interstitium. We measured the
clearance of aerosolized technetium-labeled albumin (molecular weight, 69,000) from the lungs of anesthetized
guinea pigs with the aid of a gamma camera and a dedicated computer. Aerosols of the elastase (0.1 to 5 ,ug)
increased the rate of clearance of labeled albumin from the lungs in proportion to the elastase dose. Electron
microscopic studies using horseradish peroxidase as a tracer revealed that elastase interrupts intercellular tight
junctions of the epithelial lining, thereby increasing the permeability to macromolecules. The amounts of
elastase used in this report did not cause interstitial or alveolar edema, as determined by both postmortem
extravascular lung water volume measurement and morphological examination. The data indicate that the
elastase is a potentially important virulence factor in acute lung infection.
Keywords
- immunology,
- infectious diseases
Disciplines
Publication Date
February, 1990
Citation Information
Azghani, A.O., Connelly, J.C., Peterson, B. T., Gray, L.D., Collins, M.L., and Johnson, A.R., 1990. Effects of Pseudomonas aeruginosa elastase on alveolar epithelial permeability in guinea pigs. Infection & Immunity, 58: 433-438.