JAML immunotherapy targets recently activated tumor-infiltrating CD8⁺ T cells

Area of Science:

• Immunology
• Cancer Biology
• Molecular Biology

Background:

• Junctional adhesion molecule-like protein (JAML) is a co-stimulatory molecule in γδ T cells.
• JAML has emerged as a potential cancer immunotherapy target in preclinical models.
• Key aspects like human applicability, toxicity, and precise mechanism of action remain unexplored.

Purpose of the Study:

• To investigate the induction of JAML upon T cell receptor engagement.
• To identify the cellular targets and therapeutic effects of anti-JAML therapy.
• To elucidate the synergistic mechanisms of anti-JAML therapy with anti-PD-1 in cancer treatment.

Main Methods:

• Analysis of JAML induction via T cell receptor engagement.
• Investigation of cis-regulatory interactions between CD3D and JAML gene loci.
• Characterization of anti-JAML therapy in a murine melanoma model, including cellular targets and functional outcomes.

Main Results:

• JAML expression is induced by T cell receptor engagement, linked to cis-regulatory interactions between CD3D and JAML genes.
• JAML is highly expressed on tissue-resident memory CD8+ T cells across various cancer types, suggesting specific targeting potential.
• Agonistic anti-JAML therapy demonstrated specific modes of action and synergistic effects with anti-PD-1 in a preclinical melanoma model.

Conclusions:

• JAML induction is regulated by T cell receptor signaling and gene locus interactions.
• JAML represents a highly specific immunotherapy target, primarily on tissue-resident memory CD8+ T cells in cancer.
• Anti-JAML therapy shows promise as a targeted cancer immunotherapy, potentially enhancing efficacy when combined with checkpoint inhibitors like anti-PD-1.