T cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy characterized by high rates of induction failure and relapse, and effective targeted immunotherapies are lacking. Despite promising clinical progress with genome-edited CD7-directed CAR-T cells, which present significant logistical and regulatory issues, CAR-T cell therapy in T-ALL remains challenging due to the shared antigen expression between malignant and healthy T cells. This can result in CAR-T cell fratricide, T cell aplasia, and the potential for blast contamination during CAR-T cell manufacturing. Recently described CAR-T cells target non-pan-T antigens, absent on healthy T cells but expressed on specific T-ALL subsets. These antigens include CD1a (NCT05679895), which is expressed in cortical T-ALL, and CCR9. We show that CCR9 is expressed on >70% of T-ALL patients (132/180) and is maintained at relapse, with a safe expression profile in healthy hematopoietic and non-hematopoietic tissues. Further analyses showed that dual targeting of CCR9 and CD1a could benefit T-ALL patients with a greater blast coverage than single CAR-T cell treatments. We therefore developed, characterized, and preclinically validated a novel humanized CCR9-specific CAR with robust and specific antileukemic activity as a monotherapy in vitro and in vivo against cell lines, primary T-ALL samples, and patient-derived xenografts. Importantly, CCR9/CD1a dual-targeting CAR-T cells showed higher efficacy than single-targeting CAR-T cells, particularly in T-ALL cases with phenotypically heterogeneous leukemic populations. Dual CD1a/CCR9 CAR-T therapy may prevent T cell aplasia and obviate the need for allogeneic transplantation and regulatory-challenging genome engineering approaches in T-ALL.
Institut(e)Research Unit Apoptosis in Hematopoietic Stem Cells (AHS)
FörderungenAsociacion Pablo Ugarte (APU) Health Merck Foundation European Union NextGenerationEU/PRTR MICIU/AEI FEDER Funds Spanish Research Agency (AEI) MCIN/AEI European Research Council Fundacio Josep Carreras-Obra Social la Caixa European Regional Development Fund (ERDF)/EU AEI European Union Spanish Ministry of Science and Innovation Torres Quevedo contract Juan de la Cierva postdoctoral fellowship European Union (EU) Instituto de Salud Carlos III (ISCIII) through the Spanish Network of Advanced Therapies (RICORS/TERAV+) Uno Entre Cien Mil Foundation Spanish Association Against Cancer (AECC) CERCA/Generalitat de Catalunya