TIM-3 as a novel therapeutic target for eradicating acute myelogenous leukemia stem cells.

Acute myelogenous leukemia (AML) originates from self-renewing leukemic stem cells (LSCs), which represent the ultimate therapeutic target for AML. Recent studies have identified several AML LSC-specific surface antigens as candidate targets of therapeutic molecules. T cell immunoglobulin mucin-3 (TIM-3) is expressed on LSCs in most types of AML, with the exception of acute promyelocytic leukemia, but not on normal hematopoietic stem cells (HSCs). In xenograft models reconstituted with human AML LSCs or HSCs, an anti-human TIM-3 mouse IgG2a antibody with cytotoxic activities eradicates AML LSCs in vivo, but does not affect normal human hematopoiesis. Thus, TIM-3 is a promising therapeutic target for the eradication of AML LSCs.