TSLP and infection: ILC2s in both humans and mice secrete TH2-type cytokines IL-4, IL-5, and/or IL-13 in response to IL-9, IL-25, IL-33, and thymic stromal lymphopoietin (TSLP), as well as during pulmonary inflammation or infection with Nippostrongylus brasiliensis, a helminth controlled by TH2-type cytokine responses (63, 68–78).