title: Molecular aspects of microparticle phagocytosis by dendritic cells.
abstract: The ability of immature dendritic cells (iDCs) derived from human peripheral blood mononuclear cells to phagocytose poly(lactic-co-glycolic acid) (PLGA) microparticles (MPs) as compared to polystyrene MPs and the molecular aspects of this phagocytosis were investigated. Treating iDCs with PLGA or polystyrene fluorospheres of approximately 3 microm in diameter resulted in the internalization of the particles as evidenced by confocal laser scanning micrographs. This uptake of fluorospheres by DCs was decreased by pretreatment of cells with cytochalasin D or by incubation with the fluorospheres at 4 degrees C, and was sensitive to EDTA and trypsin pretreatments in a dose-dependent manner. In agreement with our previous studies, treatment of iDCs with PLGA MPs, but not with polystyrene MPs, led to DC maturation, as measured by increase in release of the autocrine maturation cytokine, tumor necrosis factor-alpha, which was dependent on ratio of PLGA MPs to DCs. Taken together, this work begins to address the role of phagocytosis on PLGA MP-induced DC maturation and the molecular mechanisms involved.
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 313 Ferst Drive, Atlanta, GA 30332, USA.
authors.forename: Mutsumi
authors.initials: M
authors.lastname: Yoshida
authors.forename: Julia E
authors.initials: JE
authors.lastname: Babensee
mesh_terms: D001672:Biocompatible Materials; D002454:Cell Differentiation; D003713:Dendritic Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D004492:Edetic Acid / Q000494:pharmacology; D005456:Fluorescent Dyes; D006801:Humans; D066298:In Vitro Techniques; D019344:Lactic Acid; D008422:Materials Testing; D008863:Microspheres; D010316:Particle Size; D010587:Phagocytosis / Q000187:drug effects / Q000502:physiology*; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D011137:Polystyrenes; D014357:Trypsin / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D001672:Biocompatible Materials; D005456:Fluorescent Dyes; D011108:Polymers; D011137:Polystyrenes; D014409:Tumor Necrosis Factor-alpha; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D004492:Edetic Acid; D014357:Trypsin