Factors affecting in vitro phagocytosis by oyster hemocytes

摘要: Abstract Hemocytes withdrawn from the pericardial cavity of American oyster, Crassostrea virginica , were settled onto monolayers immobilized fluorescent polystyrene microspheres (beads) in culture flasks. Phagocytosis was quantitated by fluorescence microscopy and flow cytometry after enzymatic detachment cells unphagocytized beads fixation cells. Unattached removed settling mixture through a discontinuous sucrose gradient. Internalization following this procedure verified transmission electron microscopy. evident within 15 min addition to monolayer. Flow showed distinct cell populations corresponding containing one five or more indicating that multiple particle phagocytosis occurs rapidly contact between particles. incubated with at various temperatures maximum phagocytic activity over wide range (10°–37°C) inhibition occurring below 8°C. Inhibition attachment bead monolayer 0° 4°C is probably major cause decreased amount observed low temperatures. Treatment cytochalasin B prior incubation inhibited phagocytosis. Incubation under atmospheres pure nitrogen helium produced no These data suggest hemocytes oyster are able phagocytize particles extremes biological completely anaerobic conditions.