Adenosine A(3) receptor stimulation inhibits migration of human eosinophils

Activation of adenosine A(3) receptors (A(3)-R) produced a dose-dependent reduction in the chemotaxis of human eosinophils to platelet-activating factor (PAF), RANTES, and leukotriene B-4 (LTB4) to a maximum of 58, 48, and 52%, respectively (P < 0.02), This effect was completely reversed by selective A(3)-R antagonists, In contrast, activation of A(1) or A(2a)-R did not affect PAF-induced eosinophil chemotaxis, PAF up-regulated the expression of CD11b/CD18, downregulated L-selectin, and also increased F-actin assembly in eosinophils. The expression of these activation markers was not influenced by A(3)-R, A(2a), or A(1)-R stimulation, Activation of A(3)-R may play an important role in inflammation by inhibiting eosinophil migration.