To determine the upstream signaling events that led to the activation of ILC2s, we noted that CML induced an inflammatory environment within the GI tract characterized by increased expression of an array of proinflammatory cytokines (e.g., GM-CSF, TNF-α, IL-6, IFN-γ, and IL-22) as well as lipids that have been implicated in inflammation. The gene discussed is CSF2; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.