To this effect, CD19-bearing pro-B (SEM) and pre-B ALL (NALM-6) cells were first incubated overnight with primary samples of γδ T cells, and subsequently SPM-1 or control agents were added and ADCC activity was indirectly monitored by measuring the appearance of the degranulation marker CD107a on the surface of the γδ T cells. Here, CD19 is linked to acute lymphoblastic leukemia.