CD83 and infection: Three of the four co-expression modules (G1, G4, G5) negatively correlated with infection status (i.e. lower expression in infected fish) and were enriched for immune response terms including “antigen processing and presentation” (GO:0019882, e.g. cd83, MHC II alpha and beta chains) and “interleukin-12 production” (GO:0032615, e.g. mast2) (Additional file 8).