CD33 and acute myeloid leukemia: The first step to prove functionality of the novel RevTMs was to analyze binding capability of the bispecific scFv-based RevTMs on the one hand towards CD33 or CD123 expressed on the AML cell lines MOLM-13 and OCI-AML3, and on the other hand towards the RevCAR-E5B9-28/3z or RevCAR-E7B6-28/3z expressed on genetically modified T-cells.