title: Salivary secretions from the ectoparasitic wasp, Eulophus pennicornis contain hydrolases, and kill host hemocytes by apoptosis.
abstract: The current work demonstrates that larvae of the ectoparasitic wasp, Eulophus pennicornis, produce salivary secretions (Ep S) that contain a variety of hydrolases. This includes medium to high levels of N-acetyl-β-glucosaminidase activity, relatively low levels of esterase (C 4) and lipase (C 14) activity, and trace levels of esterase lipase (C 8), acid phosphatise, β-galactosidase, β-glucuronidase, and α-glucosidase activity. In addition, in vitro monolayer assays indicate that both a 4 h and an 18 h incubation of hemocytes from host Lacanobia oleracea larvae in Ep S significantly increases (P < 0.001) the percentage of cells dying by apoptosis compared to the controls. Moreover, an 18 h incubation of hemocytes in Ep S (but not a 4 h incubation), also significantly increased the percentage of dead cells detected using a trypan-blue exclusion assay. The role of ectoparasitoid salivary secretions in conditioning the host by disabling hemocyte-mediated wound healing responses, and providing food for the developing wasp larvae is discussed.
authors.affiliation: The Food and Environment Research Agency, Sand Hutton, York, United Kingdom. elaine.richards@fera.gsi.gov.uk
authors.forename: Elaine H
authors.initials: EH
authors.lastname: Richards
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D006434:Hemocytes / Q000187:drug effects*; D006867:Hydrolases / Q000032:analysis / Q000494:pharmacology*; D007814:Larva / Q000201:enzymology; D012463:Saliva / Q000737:chemistry / Q000201:enzymology*; D014863:Wasps / Q000201:enzymology*
chemical_list: D006867:Hydrolases