Enhancement of macrophage superoxide anion production by amphotericin B.
Amphotericin B (AmB) appears to have some important immunomodulatory effects, but its mechanism of action has not been explained. We investigated the effects of AmB on activation of human monocyte-derived macrophages. Macrophages cultured in the presence of AmB had an enhanced capacity to produce superoxide anion after stimulation with phorbol myristate acetate. This enhancement was dose dependent within a therapeutic range of AmB levels (0.1 to 3.0 mg/liter). Macrophages cultured in the presence of AmB had enhanced surface expression of Ia antigen; phagocytosis of unopsonized zymosan, opsonized Staphylococcus aureus, or erythrocytes opsonized with C3bi or immunoglobulin G paradoxically appeared to be reduced, but results did not achieve statistical significance. AmB appears to activate macrophages and may do so via direct effects on the plasma membrane.
Wilson
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E
Division of Infectious Diseases, British Columbia's Children's Hospital, Vancouver, Canada.
Thorson
L
L
Speert
D P
DP
D000666:Amphotericin B / Q000494:pharmacology*; D002478:Cells, Cultured; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D007202:Indicators and Reagents; D008264:Macrophages / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D010587:Phagocytosis / Q000187:drug effects; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000949:Histocompatibility Antigens Class II; D007202:Indicators and Reagents; D013481:Superoxides; D000666:Amphotericin B; D013755:Tetradecanoylphorbol Acetate