IRF1 and infection: Interestingly, transcriptomic analysis of duodenal tissues of 4-day-old Arbor Acres chickens infected with 5 × 105 sporulated oocysts of precocious E. acervulina revealed that expression levels of IFN-γ, interferon regulatory factor 1, and IL-10 mRNA were significantly up-regulated in the very early timepoints (6, 18, 60, and 72 h) post-infection compared to uninfected controls [29].