Kinetics of leukocyte sequestration in the lungs of acutely septic primates: a study using 111In-labeled autologous leukocytes.
To further clarify the role of leukocytes in the pathogenesis of ARDS, we studied the localization and kinetics of leukocyte migration using 111In-labeled autologous white cell scans (111In wbc scans) in four primates made acutely septic with infusions of Escherichia coli. Whole body images were obtained with a gamma camera and were acquired on computer every 15 min beginning immediately after the E. coli infusion. Simultaneous measurements of C5a and peripheral blood leukocyte count were also obtained. Within 5 min of initiating sepsis, three major events occurred: complement activation as measured by the production of C5a, a profound fall in peripheral leukocyte count, and a significant increase in the sequestration of leukocytes in the lungs. The pulmonary sequestration reached a peak at 15 min with a mean of 152% of baseline activity. This sequestration consisted of a population that was predominantly neutrophils. Damage to the pulmonary capillary endothelium was demonstrated by an increase in extravascular lung water. The results support a role for neutrophils and complement as mediators in the pathogenesis of ARDS.
Hangen
D H
DH
Department of Respiratory Medicine, Stanford University Medical Center, California 94305-5208.
Segall
G M
GM
Harney
E W
EW
Stevens
J H
JH
McDougall
I R
IR
Raffin
T A
TA
D000208:Acute Disease; D000818:Animals; D007205:Indium Radioisotopes; D007958:Leukocyte Count; D007962:Leukocytes / Q000502:physiology*; D008168:Lung / Q000473:pathology*; D008252:Macaca fascicularis; D008297:Male; D012128:Respiratory Distress Syndrome / Q000209:etiology*; D018805:Sepsis / Q000473:pathology*
D007205:Indium Radioisotopes