Local impairment of anti-neutrophil elastase capacity in community-acquired pneumonia.
Protease-antiprotease balance in 17 patients with unilateral community-acquired pneumonia (CAP) was characterized (day 6+/-0.8). Levels and activities of alpha-1 antitrypsin (A1AT), secretory leucoprotease inhibitor (SLPI), and neutrophil elastase (NE) were quantified. Lobes were designated as infected or uninvolved according to the presence of an infiltrate on chest radiograph. NE levels in infected lobes were higher than those in uninvolved lobes, and NE levels were significantly elevated in both, compared with that in control lobes (n=18; P<.01). A1AT and SLPI levels were similar in infected and uninvolved lobes and were significantly elevated, compared with those in control lobes (P<.05 and P<.005, respectively). Anti-NE activity in infected lobes was less than that in control or uninvolved lobes (P<.05); values in the latter 2 were similar. Free NE was detected in 7 of the infected samples, indicating that anti-NE capacity is impaired. Both A1AT and SLPI were cleaved or complexed in infected lobes, and A1AT was oxidized in infected lobes. We conclude that mean elastase levels are increased and that mean anti-elastase capacity is decreased in pneumonic lobes.
Greene
Catherine
C
Respiratory Research Division, Department of Medicine, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin, Ireland. cmgreene@rcsi.ie
Taggart
Clifford
C
Lowe
Gregory
G
Gallagher
Paula
P
McElvaney
Noel
N
O'Neill
Shane
S
D000328:Adult; D000368:Aged; D000818:Animals; D017714:Community-Acquired Infections / Q000276:immunology / Q000378:metabolism*; D004848:Epithelium / Q000276:immunology; D005260:Female; D006801:Humans; D019272:Leukocyte Elastase / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D008168:Lung / Q000166:cytology / Q000201:enzymology / Q000276:immunology / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D020556:Neutrophil Infiltration; D009504:Neutrophils / Q000276:immunology; D011018:Pneumonia, Pneumococcal / Q000276:immunology / Q000378:metabolism*; D053491:Proteinase Inhibitory Proteins, Secretory; D011506:Proteins; D011956:Receptors, Cell Surface / Q000378:metabolism*; D053481:Secretory Leukocyte Peptidase Inhibitor; D000515:alpha 1-Antitrypsin / Q000378:metabolism*
D053491:Proteinase Inhibitory Proteins, Secretory; D011506:Proteins; D011956:Receptors, Cell Surface; C506814:SLPI protein, human; D053481:Secretory Leukocyte Peptidase Inhibitor; D000515:alpha 1-Antitrypsin; D019272:Leukocyte Elastase