Skin-Targeted Metal-Organic Framework-Based Subunit Vaccines

About This Grant

PROJECT SUMMARY: SKIN-TARGETED METAL-ORGANIC FRAMEWORK-BASED SUBUNIT VACCINES Driven by their affordability, manufacturability, and safety benefits over traditional vaccines, subunit antigens are an important component of modern vaccinology. However, they exhibit poor immunogenicity and efficacy, and thus, new and rational strategies are required to improve their immunogenicity and efficacy. We propose a novel skin immunization platform (SIP) to address the limitations of vaccine development with subunit antigens. Our innovative and globally deployable SIP leverages emerging vaccine technologies, including (1) metal-organic framework (MOF) nanovaccine constructs; (2) a clinically de-risked adjuvant, and (3) needle-free, thermostable, and self-applied microneedle arrays (MNAs), as well as highly immunoresponsive skin niche for the development of effective and accessible subunit vaccines. The central hypothesis of our project is that in situ harnessing of the immunologically rich milieu of skin with our SIP in a spatially and temporally controlled manner will drive the generation of robust, durable antigen-specific humoral and cellular responses in a well-tolerated manner. Our SIP is engineered in the form of rapidly separable MNAs (rsMNAs) that consist of high-quality obelisk-shaped microneedles comprising dissolving polymer matrix tips loaded with MOF vaccine constructs and non-dissolvable stems with filleted bases attached to the backing layer. Unlike traditional MNAs that require relatively longer wear times (minutes), our rsMNA design, which is enabled by the unique ability of biodegradable MOFs in protecting vaccine components against denaturing organic solvents needed to form non-dissolvable stems of microneedles, facilitates the implantation of MOF vaccines into the skin in less than 10 s via shear force. Our SIP offers the superior vaccine delivery and immunogenicity characteristics compared to needle-and-syringe (N&S) vaccines and conventional MNA-based vaccines. As such, our SIP unlocks the true potential of the skin immune system for improved cutaneous vaccination strategies with subunit antigens. Ultimately, this project will yield a rapidly translatable SIP that will provide unparalleled flexibility and efficacy for vaccination with subunit antigens, which is unattainable with the state-of-the-art immunization platforms.