Neutrophil margination, sequestration, and emigration in the lungs of L-selectin-deficient mice.
These studies tested the hypothesis that L-selectin plays a role in neutrophil traffic in the lungs, particularly in neutrophil margination, sequestration, and emigration, using L-selectin-deficient mice. No defect in neutrophil margination within either capillaries or arterioles and venules was observed in uninflamed lungs of L-selectin-deficient mice. The initial rapid sequestration of neutrophils within the pulmonary capillaries 1 min after intravascular injection of complement fragments was not prevented. In contrast, L-selectin did contribute to the prolonged neutrophil sequestration (> or = 5 min). Interestingly, neutrophil accumulation within noncapillary microvessels required L-selectin at both 1 and 5 min after complement injection. During bacterial pneumonias, L-selectin played a role in neutrophil accumulation within noncapillary microvessels in response to either Escherichia coli or Streptococcus pneumoniae and within capillaries in response to E. coli but not S. pneumoniae. However, L-selectin was not required for emigration of neutrophils or edema in response to either organism. These studies demonstrate a role for L-selectin in the prolonged sequestration of neutrophils in response to intravascular complement fragments, in the intracapillary accumulation of neutrophils during E. coli-induced pneumonia, and in the accumulation of neutrophils within noncapillary microvessels when induced by either intravascular complement fragments or
Doyle
N A
NA
Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
Bhagwan
S D
SD
Meek
B B
BB
Kutkoski
G J
GJ
Steeber
D A
DA
Tedder
T F
TF
Doerschuk
C M
CM
D000818:Animals; D001160:Arterioles / Q000276:immunology; D002196:Capillaries / Q000276:immunology; D002448:Cell Adhesion / Q000235:genetics* / Q000276:immunology*; D002465:Cell Movement / Q000235:genetics* / Q000276:immunology*; D003165:Complement System Proteins / Q000494:pharmacology; D004487:Edema / Q000276:immunology; D004926:Escherichia coli; D007249:Inflammation / Q000235:genetics*; D019041:L-Selectin / Q000235:genetics*; D007958:Leukocyte Count; D008168:Lung / Q000276:immunology*; D051379:Mice; D008817:Mice, Mutant Strains; D016296:Mutagenesis; D009504:Neutrophils / Q000276:immunology* / Q000502:physiology*; D018410:Pneumonia, Bacterial / Q000276:immunology; D013296:Streptococcus pneumoniae; D014699:Venules / Q000276:immunology
D019041:L-Selectin; D003165:Complement System Proteins