title: Cell stimulation with optically manipulated microsources.
abstract: Molecular gradients are important for various biological processes including the polarization of tissues and cells during embryogenesis and chemotaxis. Investigations of these phenomena require control over the chemical microenvironment of cells. We present a technique to set up molecular concentration patterns that are chemically, spatially and temporally flexible. Our strategy uses optically manipulated microsources, which steadily release molecules. Our technique enables the control of molecular concentrations over length scales down to about 1 microm and timescales from fractions of a second to an hour. We demonstrate this technique by manipulating the motility of single human neutrophils. We induced directed cell polarization and migration with microsources loaded with the chemoattractant formyl-methionine-leucine-phenylalanine. Furthermore, we triggered highly localized retraction of lamellipodia and redirection of polarization and migration with microsources releasing cytochalasin D, an inhibitor of actin polymerization.
authors.affiliation: Department of Mechanical Engineering, Yale University, New Haven, Connecticut, USA. holger.kress@yale.edu
authors.forename: Holger
authors.initials: H
authors.lastname: Kress
authors.forename: Jin-Gyu
authors.initials: JG
authors.lastname: Park
authors.forename: Cecile O
authors.initials: CO
authors.lastname: Mejean
authors.forename: Jason D
authors.initials: JD
authors.lastname: Forster
authors.forename: Jason
authors.initials: J
authors.lastname: Park
authors.forename: Spencer S
authors.initials: SS
authors.lastname: Walse
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Dianqing
authors.initials: D
authors.lastname: Wu
authors.forename: Orion D
authors.initials: OD
authors.lastname: Weiner
authors.forename: Tarek M
authors.initials: TM
authors.lastname: Fahmy
authors.forename: Eric R
authors.initials: ER
authors.lastname: Dufresne
mesh_terms: D002465:Cell Movement / Q000187:drug effects; D016764:Cell Polarity / Q000187:drug effects; D006801:Humans; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000166:cytology* / Q000187:drug effects; D055095:Optics and Photonics
chemical_list: D009240:N-Formylmethionine Leucyl-Phenylalanine