Concurrent delivery of immune checkpoint blockade modulates T cell dynamics to enhance neoantigen vaccine-generated...

Area of Science:

• Immunology
• Oncology
• Translational Medicine

Background:

• Neoantigen vaccines show promise in cancer treatment by stimulating T cell responses.
• The mechanisms behind response and resistance to neoantigen vaccines are not fully understood.
• Immune checkpoint blockade (ICB) is a key cancer immunotherapy.

Purpose of the Study:

• To elucidate the mechanisms of response to neoantigen vaccines combined with ICB.
• To identify key T cell populations and signatures induced by combination therapy.
• To explore the role of T cell generation in draining lymph nodes for combination efficacy.

Main Methods:

• Single-cell RNA sequencing of over 100,000 T cells.
• Analysis of T cell populations, chemokine signaling, co-inhibitory receptor expression, and cytotoxicity markers.
• Investigation of T cell generation in draining lymph nodes.

Main Results:

• Combination therapy generates a specific CD8 T cell population characterized by active chemokine signaling (Cxcr3+/Ccl5+), reduced co-inhibitory receptor expression (Lag3-/Havcr2-), and enhanced cytotoxicity (Fasl+/Gzma+).
• Neoantigen-specific T cell generation within the draining lymph node is essential for the synergistic effect.
• Identified T cell signatures correlate with clonal frequency and improved patient survival.

Conclusions:

• Neoantigen vaccines synergize with immune checkpoint blockade to enhance antitumor immunity.
• The study defines a unique neoantigen-reactive T cell signature associated with therapeutic success.
• These findings provide a basis for developing novel combination immunotherapy strategies.