Selective expansion of chimeric antigen receptor-targeted T-cells with potent effector function using interleukin-4

Area of Science:

• Immunology
• Cancer Biology
• Biotechnology

Background:

• Chimeric antigen receptor (CAR) T-cell therapy shows promise but faces challenges with T-cell expansion and survival in patients.
• Existing CAR T-cell immunotherapies have yielded disappointing clinical results due to these limitations.

Purpose of the Study:

• To develop a novel system for selective proliferation of CAR T-cells using Interleukin-4 (IL-4).
• To engineer T-cells that can be expanded ex vivo and sustain survival in vivo for enhanced cancer immunotherapy.

Main Methods:

• Engineered a chimeric cytokine receptor (4alphabeta) by fusing the IL-4 receptor alpha (IL-4Ralpha) ectodomain to the beta(c) subunit.
• Co-expressed 4alphabeta with a MUC1-specific CAR in human T-cells.
• Stimulated T-cells with IL-4 to assess proliferation, signaling pathways (STAT3/STAT5/ERK), and anti-tumor activity.

Main Results:

• IL-4 induced exponential proliferation of 4alphabeta-expressing T-cells, mimicking IL-2 effects.
• Engineered T-cells demonstrated potent and repeated destruction of MUC1-expressing tumors in vitro and expanded significantly.
• T-cells maintained antigen specificity, type 1 polarity, and cytokine dependence after prolonged IL-4 culture.
• The system proved effective for CARs targeting additional tumor antigens and allowed rapid, GMP-compliant T-cell expansion.

Conclusions:

• Developed a proof-of-principle system for IL-4-enhanced T-cell immunotherapy of cancer.
• This approach enables selective and robust ex vivo expansion of CAR T-cells.
• The findings support the potential for improved CAR T-cell therapy efficacy through IL-4-mediated expansion and survival.