Phospholipase D mediates Fc gamma receptor activation of neutrophils and provides specificity between high-valency immune complexes and fMLP signaling pathways.
AuthorsGewirtz AT, Simons ER
JournalJ Leukoc Biol
PubMed ID9103240
'Neutrophils phagocytize high-valency immune complexes (HIC) by an Fc gamma receptor-mediated mechanism, activating an oxidative burst and initiating degranulation. In contrast, neutrophils exhibit chemotaxis to N-formylated peptides [e.g., N-formyl-methionyl-leucyl-phenylalanine (fMLP)] and secrete far fewer oxidants or granule contents than neutrophils activated by HIC. However, if neutrophils are treated with cytochalasin ... More
Intramolecularly quenched BODIPY-labeled phospholipid analogs in phospholipase A(2) and platelet-activating factor acetylhydrolase assays and in vivo fluorescence imaging.
AuthorsHendrickson HS, Hendrickson EK, Johnson ID, Farber SA
JournalAnal Biochem
PubMed ID10585741
Phospholipase substrate analogs containing both a fluorescent BODIPY group and a quenching 2,4-dinitrophenyl (DNP) group were synthesized. They showed little fluorescence, but upon hydrolysis became fluorescent as the quenching group was removed. Two substrates were phosphatidylethanolamine analogs with a BODIPY-pentanoyl group at the sn-2 position and DNP linked to the ... More
Neutrophil degranulation and phospholipase D activation are enhanced if the Na+/H+ antiport is blocked.
AuthorsGewirtz AT, Seetoo KF, Simons ER
JournalJ Leukoc Biol
PubMed ID9665282
Neutrophils phagocytize high-valency immune complexes (HIC) by an Fc receptor-mediated mechanism. Engaging Fc receptors in this manner induces PMN to generate superoxide and release the contents of both their specific and azurophilic granules. Signaling events that precede and accompany PMN secretion include activation of phospholipase D (PLD), as well as ... More