Expression of VLA-4 on eosinophils decreases in patients with eosinophilia.
BACKGROUND
It is assumed that the very late antigen-4 (VLA-4) plays a key role in selective migration and accumulation of eosinophils to the allergic inflammatory focus. The regulatory mechanism for VLA-4 expression is poorly understood, as is its relationship between other adhesion molecules.


OBJECTIVE
The aim of the study was to elucidate the relationship between VLA-4 expression and the activation of eosinophils.


METHODS
The surface expression of VLA-4, Mac-1, ICAM-1, CD4, CD25, CD69, CD89, IL-5 receptor and GM-CSF receptor on eosinophils isolated from the peripheral blood of 15 patients with eosinophilia and 16 healthy volunteers was measured.


RESULTS
The surface expression of VLA-4 presented in mean fluorescent intensity by flow-cytometric analysis showed a significant decrease in the patients with eosinophilia (>700 eosinophils/microl) compared to that of the subjects without eosinophilia. On the other hand, the surface expression of Mac-1 was significantly increased in the patients with eosinophilia. There was an inverse correlation between the expression of VLA-4 and that of Mac-1 (r = -0.81) on the eosinophils obtained from the patients with eosinophilia.


CONCLUSIONS
The changes on the surface expressions of Mac-1 and VLA-4 may be indicating the activation of eosinophils in the patients with eosinophilia and may contribute to their migration to the allergic inflammatory focus.
Kayaba
H
H
Central Clinical Laboratory, Akita University Hospital, Akita, Japan. kayaba@yukari.hos.akita-u.ac.jp
Yamada
Y
Y
Cui
C H
CH
Saito
N
N
Honda
K
K
Kobayashi
Y
Y
Urayama
O
O
Chihara
J
J
D000328:Adult; D002478:Cells, Cultured; D002648:Child; D004802:Eosinophilia / Q000175:diagnosis / Q000276:immunology*; D004804:Eosinophils / Q000276:immunology*; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000175:diagnosis / Q000276:immunology; D039041:Integrin alpha4beta1; D016023:Integrins / Q000378:metabolism*; D016177:Macrophage-1 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D016201:Receptors, Lymphocyte Homing / Q000378:metabolism*
D039041:Integrin alpha4beta1; D016023:Integrins; D016177:Macrophage-1 Antigen; D016201:Receptors, Lymphocyte Homing