[Aggregation of human neutrophils induced by phytohemagglutinin]

Phytohemagglutinin-induced aggregation of circulating neutrophils was studied in 13 normal subjects. The interference caused by various drugs (vinblastine, cytochalasin B, indomethacin, nicardipine and flunarizine) was tested. The modifications in the aggregation values induced by these drugs are in favour of an evident dependence of the phenomenon upon the trans-membrane flow of calcium ions and the calmodulin function and of a limited dependence upon the microtubular function.