title: A cell permeant peptide containing the cytoplasmic tail sequence of Fc receptor type IIA reduces calcium signaling and phagolysosome formation in neutrophils.
abstract: Receptors for the Fc domain of IgG mediate target recognition, signal transduction, and effector functions including antibody-dependent cytolysis, phagocytosis, and phagolysosome formation. To better understand FcR-mediated functions and to identify potential therapeutic strategies, we employed cell-penetrating ("Trojan") peptides to deliver "wild-type" (LTL) or modified (AAA) FcgammaRIIA tail sequences to the neutrophil's cytoplasm. The Trojan-LTL peptide appeared to label the endoplasmic reticulum whereas the Trojan-AAA peptide distributed throughout the cytoplasm. The Trojan-LTL peptide, but not the Trojan-AAA peptide, decreased Ca(2+) signaling at the phagosome and reduced phagolysosome formation. These studies suggest that FcgammaRIIA's tail can act as a peptide decoy thereby blunting FcgammaRIIA-mediated processes, which, in turn, suggests a possible route in managing inflammatory tissue damage.
authors.affiliation: Department of Ophthalmology and Visual Sciences, The University of Michigan Medical School, Ann Arbor, 48105, USA.
authors.forename: Andrea J
authors.initials: AJ
authors.lastname: Clark
authors.forename: Howard R
authors.initials: HR
authors.lastname: Petty
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D020013:Calcium Signaling / Q000502:physiology*; D002463:Cell Membrane Permeability / Q000502:physiology*; D006801:Humans; D008247:Lysosomes / Q000378:metabolism*; D008561:Membrane Fusion; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000166:cytology / Q000378:metabolism*; D010455:Peptides / Q000235:genetics / Q000378:metabolism*; D010588:Phagosomes / Q000378:metabolism*; D017452:Receptors, IgG / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism
chemical_list: C080568:Fc gamma receptor IIA; D010455:Peptides; D017452:Receptors, IgG