Increased hypodense eosinophils after activation with PAF-acether and calcium ionophore in asthmatic subjects.
Eosinophils play a major role in the pathogenesis of bronchial asthma. In this study, we examined the density characteristics of blood eosinophils from 9 normal healthy individuals and 9 allergic asthmatic patients. Furthermore, the effect of platelet-activating factor, a potent mediator of inflammation, and calcium ionophore, A23187, on the density of normodense eosinophils (density > 1.085 g/ml) has also been examined. Initially, asthmatic patients had 27.0 +/- 1.1% eosinophils of lighter density (density < or = 1.081 g/ml), significantly greater than that in the normal individuals (7.5 +/- 0.5%). After exposure to platelet-activating factor (1 microM) or calcium ionophore (A23187, 1 microgram/ml), the normodense eosinophils switched to hypodense in both groups: 16.7 +/- 2.1% and 54.2 +/- 3.7%, respectively, in normal individuals, and 30.6 +/- 5.7% and 77.4 +/- 2.3%, respectively, in asthmatic patients. These data demonstrated that a certain percentage of normodense eosinophils from asthmatics and normal subjects switched to hypodense after activation with platelet-activating factor or calcium ionophore. Furthermore, eosinophils from asthmatics switched to a greater degree than in normal subjects, suggesting that the normodense eosinophils in asthmatics become primed probably by endogenously released mediators.
Agrawal
D K
DK
Allergic Disease Center, Creighton University School of Medicine, Omaha, Nebraska 68178, USA.
Sarmiento
E U
EU
Nabe
M
M
Miyagawa
H
H
Townley
R G
RG
D000328:Adult; D001249:Asthma / Q000097:blood*; D000001:Calcimycin / Q000494:pharmacology*; D002499:Centrifugation, Density Gradient; D004804:Eosinophils / Q000187:drug effects / Q000473:pathology*; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000494:pharmacology*; D007476:Ionophores / Q000494:pharmacology*; D007958:Leukocyte Count; D008297:Male; D010972:Platelet Activating Factor / Q000031:analogs & derivatives / Q000494:pharmacology*
D018836:Inflammation Mediators; D007476:Ionophores; C029271:O-deacetyl platelet activating factor; D010972:Platelet Activating Factor; D000001:Calcimycin