Background: C-C chemokines and adhesion molecules expressed on eosinophils play an important role in the pathology of allergic inflammatory disease. C-C chemokines such as eotaxin or RANTES are involved in beta(2) integrin expression on purified eosinophils; so far we have no data on unpurified eosinophils in the peripheral blood. We measured beta(1) and beta(2) integrin activation after stimulation with eotaxin or RANTES in vitro using whole-blood flow-cytometric analysis.
Methods: Heparinized whole blood obtained from allergic patients with eosinophilia or normal subjects was diluted with the same volume of RPMI 1640, and then cells were incubated in the presence or absence of PMA/ionomycin or chemokines for 45 min at 37 degrees C. After hemolyzation with lysing solution, expression of CD11b, CD11a, CD18 and CD49d on eosinophils was measured using flow cytometry.
Results: The expression of CD11b, CD11a and CD18 in allergic patients was significantly higher than that in normal subjects. CD11b and CD18 expression showed a significant increase after stimulation with C-C chemokines, which was remarkable in allergic patients.
Conclusion: Eosinophils in the blood of allergic patients exhibited a higher expression of beta(2) integrins and were more sensitive to RANTES and eotaxin than those of normal subjects.
Copyright 2005 S. Karger AG, Basel.