Enhancing Efficacy of TCR-engineered CD4 + T Cells Via Coexpression of CD8α

Area of Science:

• Immunology
• Cancer Therapy
• Molecular Biology

Background:

• Adoptive cell therapy using T-cell receptors (TCRs) shows promise for solid tumors.
• Engineering T cells enhances clinical response depth and durability.
• MAGE-A4 is a target antigen in several cancers.

Purpose of the Study:

• To investigate coexpressing a MAGE-A4 specific TCR and CD8α coreceptor in T cells.
• To assess the impact of CD8α coexpression on CD4+ T-cell functions.
• To evaluate the potential for improved anti-tumor responses in adoptive cell therapy.

Main Methods:

• Lentiviral vector transduction of T cells to coexpress TCR and CD8α.
• Measurement of CD40 ligand expression and cytokine/chemokine secretion.
• Assessment of T-cell cytotoxic activity against 3D tumor spheroids.
• Evaluation of dendritic cell activation.

Main Results:

• Coexpression of TCR and CD8α enhanced CD4+ T-cell CD40 ligand expression.
• Increased interferon-gamma secretion was observed in engineered T cells.
• Enhanced cytotoxic activity against tumor spheroids and improved dendritic cell activation were demonstrated.

Conclusions:

• Coexpressing CD8α alongside HLA class I-restricted TCRs enhances CD4+ T-cell effector functions.
• This strategy may improve the potency and longevity of anti-tumor responses in adoptive cell therapy.
• The addition of CD8α is a viable approach to optimize TCR-engineered T-cell therapy for solid tumors.