Studies on the Mechanism of Phagocytosis Ii. Analysis of the Adhesion Phase

Endocytic mechanism of macrophages to anionic foreign substances.

“…Seno and others have suggested that macrophages have specific sites to recognize anionic groups on foreign substances, by which macrophages bind the substances to the surface and take them up into the cytoplasm (10,11,16,23,24,26,27). The general somatic cells may not have such binding sites.…”

Phagocytic Response of Rat Liver Capillary Endothelial Cells and Kupffer Cells to Positive and Negative Charged Iron Colloid Particles

“…The affinity machanism of these cells to electrostatically charged substances is not known but it may be reasoned that besides groups having affinity to positive charged substances, macrophages probably develop specific groups on their cell surface that have the affinity to negative charged particles. The hydrophobic groups in the membrane may participate in fixing the substances onto the cell surface (20). Swelling of KCs with IN may be due to the ingestion of chondroitin sulfate, the stabilizer of iron colloid.…”

“…This selectivity indicates that macrophages and CECs have developed special structures on the cell surfaces, by which they respond and ingest neighbouring substances selectively. The mechanism is unknown, but some evidence suggests that the electrostatic charges of the foreign bodies, usually of negative charge, is closely related to the mechanism as observed in mouse peritoneal macrophages and Ehrlich ascites (20) and Shimizu (12) and on observations of alveolar epithelial cells and macrophages of rat lung by Ogata et al (9) and by Tanaka (14).…”