title: C-reactive protein induces signaling through Fc gamma RIIa on HL-60 granulocytes.
abstract: Human C-reactive protein (CRP) at acute phase levels of 10-200 microg/ml triggered the phosphorylation of FcgammaRIIa, Syk kinase, and phospholipase Cgamma2 in granulocytic HL-60 cells. CRP also stimulated translocation to the membrane of both phospholipase Cgamma2 and phosphatidylinositol-3-kinase. The signaling response triggered by CRP was a rapid, early event with kinetics similar to the response elicited by human IgG. Both soluble-aggregated CRP and monomeric CRP cross-linked FcgammaRII to generate a signal of the same intensity. The results are consistent with signaling through the intrinsic immunoreceptor tyrosine-based activation motif of the cytoplasmic domain of FcgammaRIIa, the major CRP-receptor on monocytes and neutrophils that is responsible for CRP-mediated phagocytosis. The signaling events driven by CRP have the potential to regulate infiltrating neutrophil activities.
authors.affiliation: Department of Microbiology, Ohio State University, 484 West 12th Avenue, Columbus, OH 43210, USA.
authors.forename: Maoyen
authors.initials: M
authors.lastname: Chi
authors.forename: Susheela
authors.initials: S
authors.lastname: Tridandapani
authors.forename: Wangjian
authors.initials: W
authors.lastname: Zhong
authors.forename: K Mark
authors.initials: KM
authors.lastname: Coggeshall
authors.forename: Richard F
authors.initials: RF
authors.lastname: Mortensen
mesh_terms: D015703:Antigens, CD / Q000378:metabolism / Q000502:physiology*; D002097:C-Reactive Protein / Q000502:physiology*; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling / Q000276:immunology; D002462:Cell Membrane / Q000201:enzymology / Q000378:metabolism; D004792:Enzyme Precursors / Q000378:metabolism; D006098:Granulocytes / Q000201:enzymology / Q000276:immunology* / Q000378:metabolism*; D018922:HL-60 Cells; D006801:Humans; D007424:Intracellular Fluid / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D007527:Isoenzymes / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051966:Phospholipase C gamma; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D017452:Receptors, IgG / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction / Q000276:immunology*; D000072377:Syk Kinase; D010738:Type C Phospholipases / Q000378:metabolism; D019061:src-Family Kinases / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D004792:Enzyme Precursors; C080568:Fc gamma receptor IIA; D047908:Intracellular Signaling Peptides and Proteins; D007527:Isoenzymes; D017452:Receptors, IgG; D002097:C-Reactive Protein; D019869:Phosphatidylinositol 3-Kinases; D011505:Protein-Tyrosine Kinases; C000606896:SYK protein, human; D000072377:Syk Kinase; D019061:src-Family Kinases; D010738:Type C Phospholipases; D051966:Phospholipase C gamma; D002118:Calcium