Preferential tumor targeting of HER2 by iPSC-derived CAR T cells engineered to overcome multiple barriers to solid...

Area of Science:

• Immunotherapy
• Cancer Research
• Stem Cell Therapy

Background:

• Chimeric antigen receptor (CAR) T cell therapy faces challenges in solid tumors, including on-target, off-tumor toxicity, antigen heterogeneity, and tumor microenvironment resistance.
• Existing therapies struggle to overcome multiple resistance mechanisms simultaneously, limiting their efficacy.

Purpose of the Study:

• To develop an induced pluripotent stem cell (iPSC)-derived CAR T cell therapy targeting human epidermal growth factor receptor 2 (HER2) for solid tumors.
• To engineer CAR T cells to overcome common resistance mechanisms and enhance anti-tumor activity while minimizing off-tumor effects.

Main Methods:

• Developed iPSC-derived CAR T cells targeting HER2, capable of recognizing various HER2 forms (truncated, misfolded).
• Employed multiplex genome editing to enhance CAR T cell function and resistance to the tumor microenvironment.
• Combined CAR T cells with therapeutic antibodies and engineered Fc receptors (CD16a) for multi-antigen targeting.
• Incorporated genetic modifications (IL-7R-fusion, TGF-β-IL-18R, CXCR2) to improve T cell persistence, TGF-β resistance, and tumor-specific migration.

Main Results:

• iPSC-derived, HER2-targeted CAR T cells demonstrated potent HER2-specific anti-tumor activity in vitro and in vivo.
• Limited cytolytic targeting of HER2-positive normal tissues was observed, indicating improved safety.
• Combination therapy with antibodies and engineered Fc receptors facilitated comprehensive multi-antigen targeting.
• Engineered T cells showed sustained persistence, resistance to TGF-β suppression, and enhanced tumor-specific migration.

Conclusions:

• iPSC-derived CAR T cells engineered for HER2 targeting represent a promising strategy for solid tumor immunotherapy.
• Multiplex editing and combination approaches effectively address key resistance mechanisms and toxicity concerns.
• This advanced CAR T cell platform offers potential for improved efficacy and safety in treating solid tumors.