ARG1 and neoplasm: Meanwhile, cytokines secreted by Th2 cells can activate resting macrophages, involving IL-4, IL-10, and IL-13, to differentiate into anti-inflammatory macrophages and produce diverse elements inhibiting inflammation, including IL-10, TGF-β, and Arg-1, which chiefly facilitate tumor progression during tumor initiation and progression, M2-type macrophages.