TNF and helminthiasis: Accordingly, TH1 cells produce interferon (IFN)γ and tumor necrosis factor (TNF) to assist in antiviral responses, TH2 cells mediate protection against helminth infection via the production of interleukin (IL)-4, IL-5 and IL-13, and TH17 cells secrete IL-17 family cytokines to protect against bacteria and fungi1,8.