Prostaglandin E2 modulation of gene expression in an Atlantic salmon (Salmo salar) macrophage-like cell line (SHK-1)

• Published in: Developmental & Comparative Immunology
• Main Authors: Fast, M. D., Ross, N. W., Johnson, S. C.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2005
• Subjects: Real-time PCR; gene expression; cytokines; IL-1b; TNFa; MHC I; MHC II; TGF?; COX-2; inflammation; macrophage-like cell line; prostaglandin E2; Atlantic salmon; Salmo salar
• Online Access: https://doi.org/10.1016/j.dci.2005.03.007; https://nrc-publications.canada.ca/eng/view/object/?id=456a15d8-3ef0-4bbb-b43d-cc6b81f6944b; https://nrc-publications.canada.ca/fra/voir/objet/?id=456a15d8-3ef0-4bbb-b43d-cc6b81f6944b

Following lipopolysaccharide (LPS)-stimulation of Atlantic salmon (Salmo salar) macrophage-like SHK-1 cells, prostaglandin E2 (PGE2) exhibited dose-dependent inhibition of the antigen presenting molecules major histocompatability class I and II and the pro-inflammatory cytokine interleukin-1b gene expression. Prostaglandin E2 was found to be stimulatory towards cyclooxygenase-2 (COX-2) expression at higher concentrations (1!10K6 and 1!10K8 M) and inhibitory at lower concentrations (1!10K10 and 1!10K12 M) after 4 h exposure. After 24 h exposure, however, LPS-induced COX-2 expression decreased and was completely inhibited by all PGE2 concentrations (1!10K6–1!10K10 M). Incubation of SHK-1 cells with LPS alone had no effect on tumour necrosis factor a (TNFa)-like gene or transforming growth factor b-like gene expression after 4 h, however, LPS and PGE2 showed a synergistic effect on TNFa-like gene expression after 24 h. This study provides evidence for the existence of a PGE2-mediated negative feedback mechanism in the control of PGs through down-regulation of COX-2, as well as for inflammatory responses by the down-regulation of both COX-2 and IL-1b. The differential regulation of immune-related genes under these conditions further demonstrates the usefulness of the SHK-1 cell line for studying aspects of salmonid immunology. Peer reviewed: Yes NRC publication: Yes