The addition of TGFβ during NK cell propagation impairs neither fold expansion nor viability of the final expanded NK cell product, but the resulting TGFβ imprinted (TGFβi) NK cells exhibit high cytotoxicity and a pro-inflammatory hypersecretion of IFN-γ and TNFα in response to tumor targets (241). Here, TGFB1 is linked to neoplasm.