In line with this, we previously reported that when peripheral blood mononuclear cells (PBMC) from CLL patients were incubated on immobilized anti-CD3 monoclonal antibodies (aCD3) to induce T cell activation, autologous activated T lymphocytes induced the activation of CLL cells, and in vitro venetoclax resistance due to the upregulation of BCL-XL and MCL-1 (11, 12). Here, MCL1 is linked to B-cell chronic lymphocytic leukemia.