Self-Assembled STING-Activating Coordination Nanoparticles for Cancer Immunotherapy and Vaccine Applications

Area of Science:

• Immunology
• Nanomedicine
• Materials Science

Background:

• The cyclic dinucleotide (CDN) STING agonist pathway is vital for innate immunity against cancer and infections.
• CDNs possess limited drug-like properties, requiring effective delivery systems for therapeutic applications.
• Developing novel delivery platforms is crucial for enhancing STING agonist efficacy in immunotherapy and vaccines.

Purpose of the Study:

• To engineer a novel immunostimulatory delivery system for STING agonists.
• To investigate aqueous coordination interactions between CDNs and metal ions (Zn2+ and Mn2+).
• To develop a functional coordination nanoparticle (ZMCP) for enhanced therapeutic delivery and vaccine platforms.

Main Methods:

• Examined aqueous coordination interactions between CDNs and Zn2+/Mn2+ ions.
• Synthesized Zinc-Mn-CDN Particles (ZMCP) via a simple aqueous one-pot method.
• Evaluated ZMCP's antitumor efficacy in mice and its potential as a vaccine platform by loading SARS-CoV-2 antigens.

Main Results:

• Distinct crystal structures formed between CDNs and Zn2+/Mn2+ ions.
• ZMCP demonstrated robust antitumor efficacy upon local or systemic administration in mice.
• ZMCP-antigen formulations elicited strong cellular and humoral immune responses, neutralizing SARS-CoV-2.

Conclusions:

• ZMCP represents a promising self-adjuvant vaccine platform against COVID-19 and other infectious pathogens.
• This work establishes a paradigm for translational coordination nanomedicine using drug-metal ion coordination.
• Coordination medicine offers broad applicability for delivering proteins and biologics.