Abstract
With the emerging success of treating CD19 expressing B cell malignancies with ex vivo modified, autologous T cells that express CD19-directed chimeric antigen receptors (CAR), there is intense interest in expanding this evolving technology to develop effective modalities to treat other malignancies including solid tumors. Exploiting this approach to develop a therapeutic modality for T cell malignancies for which the available regimens are neither curative, nor confer long term survival we generated a lentivirus-based CAR gene transfer system to target the chemokine receptor CCR4 that is over-expressed in a spectrum of T cell malignancies as well as in CD4+ CD25+ Foxp3+ T regulatory cells that accumulate in the tumor microenvironment constituting a barrier against anti-tumor immunity. Ex vivo modified, donor-derived T cells that expressed CCR4 directed CAR displayed antigen-dependent potent cytotoxicity against patient-derived cell lines representing ATL, CTCL, ALCL and a subset of HDL. Furthermore, these CAR T cells also eradicated leukemia in a mouse xenograft model of ATL illustrating the potential utility of this modality in the treatment of a wide spectrum of T cell malignancies.