Regulation of phagocytosis and [Ca2+]i flux by distinct regions of an Fc receptor.
The binding of multivalent immunoglobulin G complexes to Fc receptors (Fc gamma Rs) on macrophages activates multiple immune functions. A murine macrophage cell line, but not a fibroblast cell line, that was transfected with human Fc gamma RIIA mediated phagocytosis and an intracellular Ca2+ concentration ([Ca2+]i) flux upon cross-linking of human Fc gamma RIIA. Transfected macrophages that expressed a truncated receptor lacking 17 carboxy-terminal amino acids phagocytosed small antibody complexes. However, only wild-type transfectants phagocytosed labeled erythrocytes and fluxed [Ca2+]i. Thus, the cytoplasmic domain of human Fc gamma RIIA contains distinct functional regions.
Odin
J A
JA
Department of Biochemistry, Mount Sinai Medical Center, New York, NY 10029.
Edberg
J C
JC
Painter
C J
CJ
Kimberly
R P
RP
Unkeless
J C
JC
D000818:Animals; D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation / Q000235:genetics / Q000502:physiology*; D016466:CHO Cells; D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D003001:Cloning, Molecular; D006224:Cricetinae; D006706:Homeostasis; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism; D007700:Kinetics; D008264:Macrophages; D051379:Mice; D010587:Phagocytosis; D011961:Receptors, Fc / Q000235:genetics / Q000502:physiology*; D017452:Receptors, IgG; D011994:Recombinant Proteins / Q000378:metabolism; D014162:Transfection
D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation; D007074:Immunoglobulin G; D011961:Receptors, Fc; D017452:Receptors, IgG; D011994:Recombinant Proteins; D002118:Calcium