title: Phagocytosis by Lymnaea stagnalis haemocytes: a potential role for phosphatidylinositol 3-kinase but not protein kinase A.
abstract: The molecular events that regulate phagocytosis, an important innate immune response, in invertebrate defence cells (haemocytes) are poorly understood. Lymnaea stagnalis haemocytes were used as a model to elucidate the role of cell signalling pathways in phagocytosis by molluscan defence cells. The phosphatidylinositol 3-kinase (PI3-K) inhibitor, LY294002, significantly impaired haemocyte phagocytic activity in a dose-responsive manner with 10 microM LY294002 reducing internalization of fluorescent-conjugated Escherichia coli by 62% (P < or = 0.001). In contrast, the protein kinase A (PKA) inhibitor KT5720 was without effect. Therefore, PI3-K, but not PKA, appears to control phagocytosis by haemocytes in these gastropod molluscs.
authors.affiliation: School of Life Sciences, Kingston University, Kingston-upon-Thames, Surrey KT1 2EE, UK.
authors.forename: Louise D
authors.initials: LD
authors.lastname: Plows
authors.forename: Richard T
authors.initials: RT
authors.lastname: Cook
authors.forename: Angela J
authors.initials: AJ
authors.lastname: Davies
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Walker
mesh_terms: D000818:Animals; D002227:Carbazoles / Q000494:pharmacology; D002867:Chromones / Q000494:pharmacology; D017868:Cyclic AMP-Dependent Protein Kinases / Q000187:drug effects / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006434:Hemocytes / Q000187:drug effects / Q000201:enzymology*; D007211:Indoles / Q000494:pharmacology; D008195:Lymnaea / Q000502:physiology*; D009025:Morpholines / Q000494:pharmacology; D010587:Phagocytosis / Q000187:drug effects / Q000502:physiology*; D019869:Phosphatidylinositol 3-Kinases / Q000187:drug effects / Q000378:metabolism*; D011758:Pyrroles / Q000494:pharmacology
chemical_list: D002227:Carbazoles; D002867:Chromones; D004791:Enzyme Inhibitors; D007211:Indoles; D009025:Morpholines; D011758:Pyrroles; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; C057416:KT 5720; D019869:Phosphatidylinositol 3-Kinases; D017868:Cyclic AMP-Dependent Protein Kinases