TCRαβ/CD3 disruption enables CD3-specific antileukemic T cell immunotherapy

Area of Science:

• Immunology
• Cellular Therapy
• Oncology

Background:

• Chimeric antigen receptor (CAR) T cells are investigated for cancer immunotherapy.
• T-on-T cytotoxicity hinders CAR T cell therapy for T cell malignancies.
• Targeting CD3 is a potential strategy for T cell-specific therapies.

Purpose of the Study:

• To develop CD3-specific CAR T cells (3CAR) to overcome T-on-T cytotoxicity.
• To evaluate the efficacy of 3CAR T cells against T cell malignancies.
• To establish a cellular immunotherapy for T cell acute lymphoblastic leukemia (T-ALL).

Main Methods:

• Gene editing (TALEN) to disrupt the endogenous TCRαβ/CD3 complex.
• Lentiviral transduction to introduce an anti-CD3ε CAR (OKT3).
• Assessment of 3CAR T cell viability, self-enrichment, and cytotoxicity in vitro and in vivo.

Main Results:

• Successful generation of viable 3CAR T cells after TCRαβ/CD3 disruption.
• Demonstrated specific cytotoxicity against primary T cells and T-ALL cell lines.
• Potent antileukemic effects observed in a human/murine chimeric model.

Conclusions:

• 3CAR T cells overcome T-on-T cytotoxicity, enabling effective cellular immunotherapy for T cell malignancies.
• This strategy facilitates T cell eradication and leukemic remission.
• 3CAR T cells show promise as a bridge to allogeneic stem cell transplantation.