Preclinical development of a protocol for the manufacturing of anti-CD5 CAR-T lymphocytes for the treatment of T-lineage acute lymphoblastic leukemia and lymphoma

The development of cell therapy methods for T-lineage acute lymphoblastic leukemia remains a relevant clinical challenge.The current study presents a preclinical stage of anti-CD5 CAR-T cell development without the use of additional geneticmodifications, relying on down-regulation of CD5. The resulting cell products demonstrated sufficient expansion rates and CARexpression levels, the predominance of the Tem phenotype (CD197–CD45RA–) and low expression of exhaustion markers (PD-1,CD57, TIGIT). The antitumor function was confirmed both in vitro through the assessment of degranulation, cytokine production,and cytotoxicity against the Jurkat cell line, and in vivo through the evaluation of CD5+ leukemia elimination in a murine model.The data obtained may serve as a basis for the development of a clinical manufacturing protocol for anti-CD5 CAR-T cells. Thestudy was approved by the Independent Ethics Committee and the Scientific Council of the Dmitry Rogachev National MedicalResearch Center of Pediatric Hematology, Oncology and Immunology.