Characterising the mucosal immune response in the Greater Amber-jack (Seriola dumerili)

Abstract

Production of the greater amberjack (Seriola dumerili) is increasing rapidly in European aquaculture. However this rapid increase in production has highlighted bottlenecks in several aspects of their rearing, including knowledge oftheir susceptibility to infection. Indeed, currently little is known about the immune system and immune response in this species which severely limits approaches for disease control, should widespread disease outbreaks arise. Therefore, this project aims to characterise the immune responsein the greater amberjack, with an emphasison mucosal immunity, following stimulation with PAMPsand bacterial/parasite infection.At the beginning of this project therewere noimmune genesthat hadbeen sequenced for the greater amberjack, which madeanalysis of the immune response problematic. Therefore, before analysis of the immune responsecouldbegin,key mucosal immune genes had tobe identified and sequenced,facilitatingthe development of QPCR primers which allowedthe monitoring of gene expression.This was achieved by utilisingthe sequencesof thesegenes in closely related species, such as yellowtail amberjack (Seriola lalandi), as well as cloning using primers to conserved domains. Once these primershad been developed the response of greater amberjack to the PAMPs poly:IC, LPS and flagellin was studiedin vitro and in vivo.This preliminary interrogation of the greater amberjack immune responseswill pave the way for future experiments to studythe impact of dietary treatments on expression of key immune molecules as well asstudy ofthe immune response to pathogeninfection.