Specific binding of IL-8 to rabbit alpha-macroglobulin modulates IL-8 function in the lung.
OBJECTIVE
The purpose of this study was to compare chemotactic activity of IL-8 alone with that of IL-8 reacted with rabbit alpha-macroglobulins (alphaM) in vivo.


METHODS
Initially the binding of recombinant human IL-8 (rhIL-8) to rabbit alphaM was studied. 125I-labeled rhIL-8 was incubated with alphaM, and electrophoresed on native 5% gels or SDS-polyacrylamide 4-20% gradient gels. Next, rhIL-8 or rhIL-8 bound to alphaM was administered via an endotracheal tube to rabbit's lungs.


METHODS
An endotracheal tube was wedged into a segment of the lobe of each lung, and a sample instilled through the tube into this segment. After 4 h the lungs were lavaged.


RESULTS
rhIL-8 bound to alphaM retained its full chemotactic activity in vitro but exhibited a diminished ability to induce the influx of neutrophils into the rabbit lung.


CONCLUSIONS
The data suggest that alphaM may facilitate IL-8 clearance from the lung.
Kurdowska
A
A
Department of Biochemistry, University of Texas Health Center, Tyler 75708, USA. anna.kurdowska@uthct.edu
Fujisawa
N
N
Peterson
B
B
Carr
F K
FK
Noble
J M
JM
Alden
S M
SM
Miller
E J
EJ
Teodorescu
M
M
D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology; D002634:Chemotaxis, Leukocyte; D004591:Electrophoresis, Polyacrylamide Gel; D016209:Interleukin-8 / Q000378:metabolism* / Q000502:physiology*; D008168:Lung / Q000276:immunology*; D020556:Neutrophil Infiltration; D009504:Neutrophils / Q000276:immunology; D011817:Rabbits; D011994:Recombinant Proteins / Q000378:metabolism; D000511:alpha-Macroglobulins / Q000378:metabolism* / Q000502:physiology*
D016209:Interleukin-8; D011994:Recombinant Proteins; D000511:alpha-Macroglobulins