title: Modulation of cellular innate immunity by Lepeophtheirus salmonis secretory products.
abstract: Lepeophtheirus salmonis produces pharmacologically active substances that have been shown to modify genetic expression of inflammatory mediators in SHK-1 cells and head kidney macrophages of salmon. Differences in genetic expression among genera of Oncorhynchus and Salmo reflect different susceptibilities to L. salmonis. This study was conducted to determine if the presence of L. salmonis secretory products (SEPs)(1) alters the cellular innate immune response (specifically macrophage function) among several salmonids. Phagocytic assays were performed using SHK-1 cells and macrophages isolated from pink (Oncorhynchus gorbuscha), chum (Oncorhynchus keta) and Atlantic (Salmo salar) salmon following incubation with SEPs and Aeromonas salmonicida. Respiratory burst assays were analyzed using pink, chum and Atlantic salmon macrophages after exposure to SEPs. For SHK-1 cells, incubation with SEPS led to dose-dependent increases in phagocytosis. Following incubation with SEPs, chum salmon macrophages had the highest phagocytic index (55.1%) followed by Atlantic (26.4%) and pink (15.8%) salmon. In contrast, respiratory burst response was greatest in pink salmon and minimal in the other two species. Our results suggest that the cellular innate immune response of salmon is modified in the presence of L. salmonis secretions and differences observed among species provide insight into species-specific consequences of sea lice infection.
authors.affiliation: Faculty of Land and Food Systems, University of British Columbia, 2357 Main Mall, Vancouver, BC V6T 1Z4, Canada; Fisheries and Aquaculture Department, Vancouver Island University, 900 Fifth Street, Nanaimo, BC V9R 5S5, Canada. Electronic address: danielle.lewis@alumni.ubc.ca.
authors.forename: D L
authors.initials: DL
authors.lastname: Lewis
authors.affiliation: Fisheries and Aquaculture Department, Vancouver Island University, 900 Fifth Street, Nanaimo, BC V9R 5S5, Canada.
authors.forename: D E
authors.initials: DE
authors.lastname: Barker
authors.affiliation: UBC Centre for Aquaculture and Environmental Research, 4160 Marine Drive, West Vancouver, BC V7V 1N6, Canada.
authors.forename: R S
authors.initials: RS
authors.lastname: McKinley
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003124:Colorimetry; D033342:Copepoda / Q000378:metabolism*; D015232:Dinoprostone / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D005260:Female; D007111:Immunity, Cellular / Q000187:drug effects*; D008264:Macrophages; D008297:Male; D010587:Phagocytosis / Q000187:drug effects*; D011506:Proteins / Q000378:metabolism / Q000494:pharmacology*; D016897:Respiratory Burst
chemical_list: D011506:Proteins; D015232:Dinoprostone
keywords: Immunomodulation; Innate immunity; Lepeophtheirus salmonis; Macrophage; Salmonids