TLR9 Agonists Potentiate Adoptive T-cell Therapy in Cancer through a B-cell-CD2 Costimulatory Axis.

TLR9-activated B cells enhance CD8+ T-cell antitumor activity via a CD2-dependent costimulation axis in cancer therapy.

• Why it matters: Understanding how innate immune signals boost adoptive T-cell therapy could improve treatment outcomes for solid tumors, addressing resistance issues.
• What they did: The study used murine and human models to show that TLR9 agonist CpG programs CD8+ T cells for better effector function, with CD2 signaling being essential for this enhancement, while other costimulatory pathways were not involved.
• The result: Elevated CD2 expression in human tumors correlates with improved survival, indicating that targeting the B-cell-CD2 pathway may be a promising strategy to improve ACT efficacy in solid tumor patients.