TNFSF4 and acute lymphoblastic leukemia: , by studying 44 ALL patients and ALL cell lines (NALM-16, JURKAT, SD-1, REH, SUP -B15, TOM-1, and), have shown that the expression of the OX40L checkpoint on NK cells and its interaction with OX40 on ALL cells causes the activation of NK cells and depletion of Leukemic cells [91].