Activation of neutrophil like HL-60 cells by prostaglandin E(2)

The effect of prostaglandins on neutrophil activation has been studied using the human promyelocytic leukemic cell line HL-60, differentiated with dimethyl sulfoxide (DMSO). Prostaglandin E-2 (PGE(2)) directly stimulated HL-60 cell aggregation with an EC50 value of 30 nM. Studies with prostanoid receptor-selective agonists suggest that the activation of HL-60 cells by PGE, was mediated via the EP2 receptor. Human neutrophils did not aggregate in response to PGE(2), but PGE(2) inhibited the N-formyl-methionyl-leucyl-phenylalanine (FMLP)-stimulated increase in intracellular calcium ([Ca2+](i)) in both neutrophils and HL-60 cells. In contrast with the aggregation response to FMLP, the aggregation response of HL-60 cells to PGE(2) was independent of extracellular calcium and did not involve mobilization of intracellular calcium.