SHAPE OSCILLATIONS - A FUNDAMENTAL RESPONSE OF HUMAN NEUTROPHILS STIMULATED BY CHEMOTACTIC PEPTIDES

Neutrophils undergo periodic cytoskeletal rearrangements that lead to cycles of shape change, ultimately resulting in cell translocation. Re peated stimulation of resting neutrophils with subsaturating chemoattr actant doses induced transient sinusoidal oscillations in neutrophil f ilamentous actin content at the second and subsequent stimulations, Os cillation frequencies increased with increasing concentration of the f irst stimulus, In contrast, neutrophils pretreated with the phosphatid ylinositol 3-kinase inhibitor (17-hydroxy)wortmannin displayed shape o scillations with the first stimulation, and the frequencies were indep endent of agonist type and dose, We demonstrate that oscillations in f ilamentous actin, which may be critical for neutrophil motility, can b e induced in untreated cells by natural peptide chemoattractants.