IL1B and infection: Other important genes upregulated in the same fish included pro-inflammatory cytokine il1b, and the highly pleiotropic transcription factors stat1a and stat3. After infection with SVCV most of these mMPG were downregulated in rag1−/− fish (Table 1, column B), while only il1b, irf6, and hspb were upregulated in SVCV-infected rag1+/+ fish (Table 3, column C).