Polymorphonuclear leukocytes (PMN)and soluble or particulate matter interact, to produce chemiluminescence (CL)which links to activation of the oxidative metabolism of the cells. While studying the characteristics of the CL induced by antibody-coated crude membrane fragments of K562 tumor cells, the result was observed that PMN were not triggered to a CL response in the absence of antibodies or the fragments. Furthermore, the fact that Cl could be inhibited by colchicine which disturb the integrity of the PMN cytoskeleton, indicate that the cytoskeleton is linked to Fc receptor binding or signal transduction. The luminol-enhanced CL was dependent on the presence of calcium and hydroxyl radicals were involved.