Activity of pulmonary edema fluid interleukin-8 bound to alpha(2)-macroglobulin in patients with acute lung injury.
The formation of alpha(2)-macroglobulin (alpha(2)-M)/interleukin-8 (IL-8) complexes may influence the biological activity of IL-8 and the quantitative assessment of IL-8 activity. Therefore, in this study, concentrations of free IL-8 and IL-8 complexes with alpha(2)-M were measured in pulmonary edema fluid samples from patients with acute lung injury/acute respiratory distress syndrome (ALI/ARDS) and compared with control patients with hydrostatic pulmonary edema. Patients with ALI/ARDS had significantly higher concentrations of alpha(2)-M (P < 0.01) as well as alpha(2)-M/IL-8 complexes (P < 0.05). Because a substantial amount of IL-8 is complexed to alpha(2)-M, standard assays of free IL-8 may significantly underestimate the concentration of biologically active IL-8 in the distal air spaces of patients with ALI/ARDS. Furthermore, IL-8 bound to alpha(2)-M retained its biological activity, and this fraction of IL-8 was protected from proteolytic degradation. Thus complex formation may modulate the acute inflammatory process in the lung.
Kurdowska
Anna K
AK
Department of Biochemistry, University of Texas Health Center, Tyler, Texas 75708, USA. anna.kurdowska@uthct.edu
Geiser
Thomas K
TK
Alden
Susanne M
SM
Dziadek
Bozena R
BR
Noble
James M
JM
Nuckton
Thomas J
TJ
Matthay
Michael A
MA
D000208:Acute Disease; D015633:Extravascular Lung Water / Q000276:immunology / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D016209:Interleukin-8 / Q000378:metabolism*; D016676:Macrophages, Alveolar / Q000276:immunology; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism; D010196:Pancreatic Elastase / Q000378:metabolism; D011654:Pulmonary Edema / Q000276:immunology* / Q000378:metabolism*; D012128:Respiratory Distress Syndrome / Q000276:immunology / Q000378:metabolism; D000511:alpha-Macroglobulins / Q000378:metabolism*
D016209:Interleukin-8; D000511:alpha-Macroglobulins; D010196:Pancreatic Elastase