IFN-λ treatment produces a proliferative phenotype in GI stem cells. (K) Functional enrichment analysis of differentially expressed genes: canonical pathway enrichment analysis (log₂ fold-change .0.58, and adjusted P value <.05) in sorted Lgr5⁺ and Lgr5⁻ epithelial cells after in vivo PEG-rIL-29 treatment relative to genotype-matched PBS-treated samples using Ingenuity pathway analysis. Enrichment of canonical pathways associated with immune responses (left) and regulation of cellular proliferation (right). Bubbles represent significant pathway enrichment, as determined by Fisher’s exact test. Bubble diameter represents the log₁₀P value as determined by Fisher’s exact test. Crosses signify a lack of significant pathway enrichment, color indicates predicted pathway activation (red) or predicted inhibition (blue), and white bubbles represent significant functional enrichment of pathways with no available prediction patterns.