Transfection of an Fc gamma receptor cDNA induces T cells to become phagocytic.
The human receptor Fc gamma RIIA for the Fc portion of IgG (Fc gamma) was expressed in a human T-cell line and conferred on these cells the ability to perform IgG antibody-stimulated phagocytosis. Crosslinking Fc gamma RIIA with anti-Fc gamma RII monoclonal antibody also induced tyrosine phosphorylation of multiple proteins including Fc gamma RIIA, ZAP-70, p72SYK, and phospholipase C gamma 1 subunit and an increase in intracellular Ca2+ concentration. The T cell receptor-associated zeta-chain was not tyrosine-phosphorylated after crosslinking of Fc gamma RIIA, suggesting that the Fc gamma RIIA-mediated signals were independent of CD3. Fc gamma RIIA-mediated signal transduction was defective in a transfected mutant T-cell line exhibiting reduced expression of the tyrosine kinases LCK and FYN. These studies indicate that certain T cells can assume phagocytic properties after transfection of cDNA encoding an Fc gamma receptor with the capability of inducing a phagocytic signal.
Hunter
S
S
Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia 19104.
Kamoun
M
M
Schreiber
A D
AD
D000911:Antibodies, Monoclonal / Q000494:pharmacology; D017252:CD3 Complex / Q000302:isolation & purification / Q000502:physiology; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D006801:Humans; D007376:Interleukin-2 / Q000032:analysis / Q000096:biosynthesis; D016297:Mutagenesis, Site-Directed; D010587:Phagocytosis / Q000276:immunology*; D010750:Phosphoproteins / Q000302:isolation & purification / Q000378:metabolism; D010766:Phosphorylation; D017452:Receptors, IgG / Q000096:biosynthesis / Q000302:isolation & purification / Q000502:physiology*; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000276:immunology*; D014162:Transfection; D014407:Tumor Cells, Cultured; D010738:Type C Phospholipases / Q000378:metabolism
D000911:Antibodies, Monoclonal; D017252:CD3 Complex; D007376:Interleukin-2; D010750:Phosphoproteins; D017452:Receptors, IgG; D010738:Type C Phospholipases; D002118:Calcium