Reversing immunotherapy resistance in cold tumors by weaponizing pyroptosis with a dual-payload nanotuner

Area of Science:

• Immunology
• Nanotechnology
• Oncology

Background:

• Immune checkpoint blockade (ICB) efficacy is limited by poor tumor antigenicity and weak immune responses.
• Gasdermin-mediated pyroptosis is a promising strategy to enhance ICB by increasing immunogenicity.
• Engineering nanoplatforms for coordinated pyroptosis induction remains a challenge.

Purpose of the Study:

• To develop a nanoplatform capable of inducing pyroptosis through multiple coordinated pathways.
• To investigate the potential of this nanoplatform in overcoming resistance to anti-PD-1 therapy.

Main Methods:

• A sialic acid-functionalized lipid nanoparticle (LNP) co-delivering GSDME mRNA and a self-assembling small molecule (1541B) was engineered.
• GSDME mRNA replenished pyroptotic substrate, while 1541B self-assembled into nanofibers to activate caspase-3 and initiate non-canonical pyroptosis.
• Nanofibers disrupted mitochondrial function, leading to caspase-1-mediated GSDMD cleavage, amplifying pyroptosis via the canonical pathway.

Main Results:

• The engineered LNP successfully induced pyroptosis via both canonical and non-canonical pathways.
• This dual-pathway pyroptosis amplified pro-inflammatory cytokine release and remodeled the tumor immune microenvironment.
• The nano-pyroptosis inducer demonstrated efficacy in overcoming resistance to anti-PD-1 therapy, enhancing systemic anti-tumor immunity and inhibiting tumor growth.

Conclusions:

• This study establishes a novel therapeutic paradigm for reversing ICB resistance through orchestrated pyroptosis amplification.
• The developed nanoplatform offers a promising strategy for enhancing cancer immunotherapy by overcoming immune evasion mechanisms.