title: Human anti-peptidoglycan-IgG-mediated opsonophagocytosis is controlled by calcium mobilization in phorbol myristate acetate-treated U937 cells.
abstract: Recently, we demonstrated that human serum amyloid P component (SAP) specifically recognizes exposed bacterial peptidoglycan (PGN) of wall teichoic acid (WTA)-deficient Staphylococcus aureus ΔtagO mutant cells and then induces complement-independent phagocytosis. In our preliminary experiments, we found the existence of human serum immunoglobulins that recognize S. aureus PGN (anti-PGNIgGs), which may be involved in complement-dependent opsonophagocytosis against infected S. aureus cells. We assumed that purified serum anti-PGN-IgGs and S. aureus ΔtagO mutant cells are good tools to study the molecular mechanism of anti-PGN-IgG-mediated phagocytosis. Therefore, we tried to identify the intracellular molecule(s) that is involved in the anti-PGN-IgG-mediated phagocytosis using purified human serum anti-PGN-IgGs and different S. aureus mutant cells. Here, we show that anti-PGN-IgG-mediated phagocytosis in phorbol myristate acetate-treated U937 cells is mediated by Ca2(+) release from intracellular Ca2(+) stores and anti-PGN-IgG dependent Ca2(+) mobilization is controlled via a phospholipase Cγ-2-mediated pathway.
authors.affiliation: The Global Research Laboratory of Insect Symbiosis, College of Pharmacy, Pusan National University, Busan 609-735, Korea.
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Department of Biochemistry, Chonbuk National University Medical School, Jeonju 561-180, Korea.
authors.forename: So-Young
authors.initials: SY
authors.lastname: Rah
authors.affiliation: The Global Research Laboratory of Insect Symbiosis, College of Pharmacy, Pusan National University, Busan 609-735, Korea.
authors.forename: Jang-Hyun
authors.initials: JH
authors.lastname: An
authors.affiliation: Faculty of Pharmaceutical Sciences, Nagasaki International University, Nagasaki 859-3298, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kurokawa
authors.affiliation: Department of Biochemistry, Chonbuk National University Medical School, Jeonju 561-180, Korea.
authors.forename: Uh-Hyun
authors.initials: UH
authors.lastname: Kim
authors.affiliation: The Global Research Laboratory of Insect Symbiosis, College of Pharmacy, Pusan National University, Busan 609-735, Korea.
authors.forename: Bok Luel
authors.initials: BL
authors.lastname: Lee
mesh_terms: D000906:Antibodies / Q000097:blood / Q000276:immunology*; D002118:Calcium / Q000378:metabolism*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood* / Q000276:immunology; D010457:Peptidoglycan / Q000276:immunology*; D010587:Phagocytosis / Q000187:drug effects*; D051966:Phospholipase C gamma / Q000378:metabolism; D013211:Staphylococcus aureus / Q000276:immunology / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D020298:U937 Cells
chemical_list: D000906:Antibodies; D007074:Immunoglobulin G; D010457:Peptidoglycan; D051966:Phospholipase C gamma; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium