Key Difference – TH1 vs TH2 Helper Cells Type 1 T helper (TH1) cells and Type 2 T helper (TH2) cells are two sub types of T helper cells that can be distinguished by the type of cytokines that they secrete. TH1 cells secrete interferon-γ (IFN-γ) and tumour necrosis factor-α (TNF-α) and mainly protect the organism against intracellular pathogens. […]