Redistribution of the Fc Receptor on Human Blood Monocytes and Peritoneal Macrophages Induced by Immunoglobulin G-Sensitized Erythrocytes

摘要: The Fc receptor is a plasma membrane component exhibiting an affinity for the C γ 3 domain of certain subclasses immunoglobulin G. Using anti-Rh o (D)-sensitized red cells (EA) in slide rosette technique, we have demonstrated translational mobility and polar redistribution this on human blood monocyte peritoneal macrophage. These cells, isolated from venous malignant ascites identified histochemically, showed time- temperature-dependent capping defined by binding six or more EA confined to cell half-perimeter. Caps formed serum were mainly extreme caps which bound appeared as morula contiguous with adherent cell. At 21°C 37°C 80% live rosettes caps; virtually none at 4°C about 25% seen PBS 21°C. Similarly, 10% 60 70% room temperature 37°C, respectively, suggesting factor(s) was important promoting capping. Capping reversibly inhibited sodium azide although inhibition incomplete even 0.1 M, concentration 10-fold higher than that giving complete lymphocyte antigen-receptor Azide also induced reversion capped diffuse, non-capped rosettes, levels comparable those studies. Re-exposure after failed increase either proportion forming fullness such indicating critical number receptors had been capped. Live spherocytosis irrespective status; changes early where minimal. Dead bore normal biconcave discs. Some rosetting ultimately hemolyzed upon prolonged incubation, erythrophagocytosis 15% 37°C.