IL1B and listeriosis: Gene set enrichment analysis (GSEA) also supports an effector-like profile, with genes up-regulated in IL-1β–exposed OT-I cells enriched for genes up-regulated in effector T cells generated during vaccinia virus (Luckey et al., 2006; Fig. 2 B) or Listeria monocytogenes infection (Pearce et al., 2009; Fig. 2 C).