title: Modulation of phagosome-lysosome fusion in mouse macrophages.
abstract: A previously described fluorescence assay has been used to characterize factors that modulate phagosome-lysosome (P-L) fusion in mouse macrophages. Fusion was not affected by enzymatic modification or by concanavalin A cross-linking of the plasma membrane or by coating the phagocytic particle with concanavalin A or immune serum. Pretreatment of cells with 10-5-10-4 M colchicine, or treatment immediately after ingestion with 1-10 microgram/ml cytochalasin did not alter P-L fusion; implying that the cytoskeleton does not control fusion in a rate-limiting way. Fusion was strikingly elevated in 5-h cultures of activated macrophages from immune-boosted mice. A lower enhancement was seen in cells activated by proteose-peptone, a nonspecific inflammatory agent.
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000201:enzymology / Q000276:immunology; D003078:Colchicine / Q000494:pharmacology; D003208:Concanavalin A / Q000494:pharmacology; D003571:Cytochalasin B / Q000494:pharmacology; D003599:Cytoskeleton / Q000187:drug effects; D004705:Endocytosis; D005260:Female; D008247:Lysosomes / Q000276:immunology*; D008264:Macrophages / Q000276:immunology*; D008297:Male; D051379:Mice; D009895:Opsonin Proteins; D010447:Peptide Hydrolases / Q000494:pharmacology; D010587:Phagocytosis
chemical_list: D009895:Opsonin Proteins; D003208:Concanavalin A; D003571:Cytochalasin B; D010447:Peptide Hydrolases; D003078:Colchicine