Toll-like receptors in maraena whitefish: Evolutionary relationship among salmonid fishes and patterns of response to Aeromonas salmonicida
2016 (English)In: Fish and Shellfish Immunology, ISSN 1050-4648, E-ISSN 1095-9947, Vol. 54, 391-401 p.Article in journal (Refereed) PublishedText
Toll-like receptors (TLRs) interact directly with particular pathogenic structures and are thus highly important to innate immunity. The present manuscript characterises a suite of 14 TLR5 in maraena whitefish (Coregonus maraena), a salmonid species with increasing importance for aquaculture. Whitefish TLRs were structurally and evolutionary analysed. The results revealed a close relationship with TLR5 from salmonid fish species rainbow trout and Atlantic salmon. Profiling the baseline expression of TLR genes in whitefish indicated that mainly members of the TLR11 family were highly expressed across all investigated tissues. A stimulation model with inactivated Aeromonas salmonicida was used to induce inflammation in the peritoneal cavity of whitefish. This bacterial challenge induced the expression of pro-inflammatory cytokine genes and evoked a strong influx of granulated cells of myeloid origin into the peritoneal cavity. As a likely consequence, the abundance of TLR-encoding transcripts increased moderately in peritoneal cells, with the highest levels of transcripts encoding non-mammalian TLR22a and a soluble TLR5 variant. In the course of inflammation, the proportion of granulated cells increased in peripheral blood accompanied by elevated TLR copy numbers in spleen and simultaneously reduced TLR copy numbers in head kidney at day 3 post-stimulation. Altogether, the present study provides in-vivo evidence for relatively modest TLR response patterns, but marked trafficking of myeloid cells as an immunophysiological consequence of A. salmonicida inflammation in whitefish. The present results contribute to improved understanding of the host-pathogen interaction in salmonid fish.
Place, publisher, year, edition, pages
2016. Vol. 54, 391-401 p.
Aeromonas salmonicida, Large granular lymphocytes, Maraena whitefish, Pathogen-associated molecular patterns, Salmonidae, Teleost
IdentifiersURN: urn:nbn:se:kth:diva-189793DOI: 10.1016/j.fsi.2016.04.125ISI: 000378451700046PubMedID: 27131902ScopusID: 2-s2.0-84964862050OAI: oai:DiVA.org:kth-189793DiVA: diva2:949565
QC 201607212016-07-212016-07-152016-07-21Bibliographically approved