Ultrastructural characteristics of alginate-induced reddish purple stainedcells (ARPC) in mouse peritoneal cavity

To characterize microscopic features of the alginate-induced reddish purple -stained cells (ARPC) using electron microscope, one ml of sodium alginate solution (10 mg/ml) was injected into Mice intraperitoneally. Mice were kil led after the injection at various time intervals to collect the peritoneal fluid. The cells contained in the fluid were collected by centrifugation a nd subjected to cytological examinations. As a result, electron Microscopy revealed that the vacuole-like organelles (VLO) contained very small amount , of electron-dense substance. The substance was stained reddish purple wit h Wright solution. ELISA using anti-alginate monoclonal antibody and uronic acid determination indicated that the substance is not phagocytosed sodium alginate but ARPC-derived cellular materials. It is concluded that the ARP C is shown to be obviously cellular organelles.