Endocytic mechanism of macrophages to anionic foreign substances.

Abstract

To study the non-immunogenic defense mechanism on organisms against foreign substances, reactions of cells to anionic colloidal particles were observed on macrophages from rat peritoneal cavity and liver tissues. As the non-antigenic anionic particles, iron colloids obtained by coating ferric hydroxide colloidal particles with potassium polyvinyl sulfate or chondroitin sulfate were used. Observations revealed that peritoneal macrophages and Kupffer cells develop surface receptors having specific affinity to anionic particles by which the cells adsorb them on the surface and internalize them into the cytoplasm for decomposition or detoxication. The other general somatic cells did not have any such receptors and were unable to take up the foreign particles having a negative surface charge.