TGFB1 and neoplasm: While TGF-β induced a slight, but not significant, decrease of the cytolytic activity (51Cr-release assays) of Vγ9Vδ2 T cells against RAJI tumor cells (Figure 2A, left), this cytokine reduced such a lytic activity to greater extent against GBM-1 cells (Figure 2A, right).