Abstract
Cells of the human mononuclear phagocyte system have recently been shown to possess cytophilic IgO molecules that promote phagocytosis of staphylococci bearing cell-wall protein A. In the present study, the possible mediation of a cytotoxic response to 51Cr-labeled sheep erythrocytes coated with protein A by cytophilic antibodies on human peritoneal macrophages was evaluated. The target cells were readily lysed by peritoneal macrophages. Cytotoxicity was blocked by pretreatment of macrophages with soluble protein or with anti-Fc F(ab′)2, fragments. In contrast, cytotoxicity was not affected by cytochalasin B; this finding suggests that cytolysis is an extracellular event. Perturbation of cytophilic IgO with particle-bound protein A elicited a chemiluminescent response from peritoneal macrophages; however, experiments with scavengers of reactive oxygen species indicated that toxic oxygen radicals may not be required for cytotoxicity. The results indicate that cytophilic antibody-mediated cytotoxicity may contribute to cellular injury as well as host-defense aspects of the inflammatory process.
Original language | English (US) |
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Pages (from-to) | 1040-1048 |
Number of pages | 9 |
Journal | Journal of Infectious Diseases |
Volume | 148 |
Issue number | 6 |
DOIs | |
State | Published - Dec 1983 |
Bibliographical note
Funding Information:This research was supported in part by grant AI-08821-10 from the National Institute of Allergy and Infectious Diseases and by a grant from the Graduate School of the University of Minnesota. Dr Verbrugh was supported by grant FOSTW02952-01 from the John E. Fogarty International Center. Dr Miller is the recipient of New Investigator Award R23 CA 32107.