Computer Image Analysis Method for Rapid Quantitation of Macrophage Phagocytosis

A new method is described for rapidly quantitating phagocytosis by adherent macrophages in culture using computer image analysis CIAof video light microscopic images. Ingestion of fluorescent microspheres by peritoneal murine macrophages is used to model phagocytosis. The grey levels of digital phase contrast and fluorescent microscopic images are used to quantitate the number of microspheres per cell. the method is semi-automatic, analyzes approximately 2 x10 3 cellshour, and simultaneously measures phagocytosis microspherescell, cell area, and density number of cellsmm2. CIA obtains the same microspherescell average as manual microscopic counting and an analytical precision of 5. As expected, CIA found that the number of microspherescell linearly increases with increasing macrophage-microsphere co-culture time or increasing microsphere concentration until macrophages become saturated.