Next-generation CD179a-CAR-T cells demonstrate potent and sustained anti-tumor activity in preclinical B-cell malignancies.

BACKGROUND

Chimeric Antigen Receptor (CAR) T-cell therapy has transformed the treatment landscape for B-cell malignancies, particularly in relapsed and refractory leukemia. However, conventional CAR constructs targeting CD19 or CD20 often result in off-tumor toxicity due to shared antigen expression on healthy B-cells. CD179a, a novel leukemia-associated antigen with limited expression on normal tissues, presents a promising alternative target for safer and more specific immunotherapy.

METHODS

A 5th-generation CAR construct targeting CD179a was engineered and transfected into human T-cells to assess its antileukemic efficacy. Functional characterization was performed using the JM1-VRL-10,423 B-cell leukemia cell line. Post-transfection, cytotoxic activity, apoptosis induction, gene expression, and tumor cell viability were quantified. To evaluate safety, CD179a-CAR T-cells were also co-cultured with normal human peripheral blood mononuclear cells (PBMCs). Additionally, the in vivo efficacy of CD179a-directed CAR T-cells was tested in a xenograft model of B-cell leukemia, using mice transplanted with CD179a+ tumor cells.

RESULTS

In vitro, CD179a-targeted CAR T-cells demonstrated potent cytotoxicity, reducing leukemia cell viability to 44.22% after 72 h, superior to both CD3/CD28-activated T-cells and 5-Fluorouracil (5-FU). Apoptosis assays confirmed early apoptotic induction in 54.3% of leukemia cells. Importantly, negligible cytotoxic effects were observed in PBMCs, indicating selective targeting. In the xenograft model, CD179a-CAR T-cells significantly reduced the expression of CD179a in leukemic cells compared to controls. Gene expression profiling further validated apoptosis pathway activation.

CONCLUSION

These findings highlight the promising antileukemic potential of CD179a-directed CAR T-cells, combining high specificity with a favorable safety profile. This in vitro and in vivo study supports the advancement of CD179a-CAR T-cell therapy as a next-generation immunotherapeutic strategy for B-cell leukemias, warranting further preclinical and clinical development.