Development of Chemotaxis and Formyl Peptide Binding in Human Promyelocytic Leukemia Cell Line (HL60)

Abstract

Abstract

HL60 lack motile behavior in general, as shown by failure to undergo random migration, chemotaxis, or phagokinesis. Upon induction with 1% DMSO, HL60 undergo myeloid differentiation and display motile behavior as measured by these three assays. Random migration and chemotaxis first appear 48 hr after DMSO induction and increase in magnitude over a 6-day period. Although lower in absolute magnitude, the chemotactic response of induced HL60 is similar to mature PMN. DMSO-treated HL60 respond chemotactically to formylpeptides, pepstatin, bacterial supernatants, and ZAS but fail to respond to GHG or VGSG. HL60 and PMN also show similar dose–response curves to formyl peptides. Uninduced HL60 lack specific [³H]FMLP binding. Specific [³H]FMLP binding appears coincidental with chemotaxis after 48 hr in 1% DMSO and both increase in parallel throughout the induction time course. These data further support the role of specific membrane receptors and cell locomotion in general in the maturation of the chemotactic response.