Biology subjects

Muscat-Rivera, J.

Publications and source records attributed to Muscat-Rivera, J..

3 recordsLinked to original sources

bioRxiv2025

Anionic lipids modulate mRNA-lipid nanoparticle immunogenicity and confer protection in a mouse model of multiple sclerosis

The modularity of mRNA-lipid nanoparticle (mRNA-LNP) platforms has enabled their rapid adaptation from infectious disease vaccines to emerging applications in immune-mediated disorders. However, extending mRNA-LNPs to autoimmune and inflammatory diseases requires precise control over immune cell targeting and immunogenicity. Here, we systematically investigate how incorporating anionic lipids into LNPs modulates both immune cell tropism and innate immune activation. Using a library of 40 distinct LNP formulations, we demonstrate that anionic lipids enhance mRNA delivery to splenic dendritic cells, reduce early cellular markers of adjuvant activity and tune cytokine responses in a lipid-dependent manner. We identify formulations that retain pro-inflammatory adjuvant activity and others that promote tolerogenic responses. A lead formulation containing the anionic lipid DOPG selectively dampens innate activation and induces IL-10 production. When encoding the myelin antigen MOG35-55, this LNP suppresses disease in a mouse model of multiple sclerosis, reducing neuroinflammation, T cell infiltration, and maintaining myelin morphology. These findings establish a framework for designing immune-targeted mRNA-LNPs with tunable immunogenicity and promote the development of antigen-specific tolerizing immunotherapies for autoimmune disease.

bioengineering↗

bioRxiv2025

Modeling Fibrosis with MASH Patient Liver-Derived Organoids.

Metabolic dysfunction-associated steatohepatitis (MASH) can lead to liver fibrosis and cirrhosis ultimately leading to liver transplantation or death. Therapeutic options for MASH-associated fibrosis are limited in part because of the lack of good model systems. To address this challenge, we developed a 3D MASH liver fibrosis model by using organoids derived from MASH patient liver co-cultured with human liver-derived hepatic stellate cells (HSC) and human peripheral blood monocytes (MC). Spontaneous self-assembly resulted in fibrotic scar-like 3D structures with senescent parenchymal cells, proliferating collagen secreting myofibroblasts (MFB) and proinflammatory TREM2+ scar-associated macrophages (MP). Single cell RNA sequencing suggested high similarity with MASH patient liver fibrotic scars. Lipid nanoparticles (LNPs) formulated with anti-YAP1siRNA could specifically and efficiently knockdown YAP1 in the MFBs, resulting in MFB senescence, a desirable therapeutic goal. This MASH patient liver-derived fibrosis model opens novel avenues towards testing treatments for MASH-associated liver fibrosis with reduced adverse effects.

bioengineering↗

bioRxiv2025

High-throughput in vivo screening using barcoded mRNA identifies lipid nanoparticles with extrahepatic tropism for cancer immunotherapy

Interest continues to grow in the use of mRNA vaccines for cancer immunotherapy. While effective for immunization against infectious diseases, current clinical lipid nanoparticle (LNP) formulations used for mRNA delivery suffer from off-target accumulation, poor immune transfection, and reactogenicity, limiting their application to cancer immunotherapy. Development of new mRNA LNPs is severely bottlenecked by the LNP discovery process, which is historically low-throughput due to reliance on low-plexity measurements. Here, we develop a next-generation high-throughput in vivo mRNA LNP screening platform based on barcoded mRNA (b-mRNA). Using this b-mRNA screening platform to simultaneously evaluate 122 LNPs, we identify novel LNP formulations capable of potent hepatic and extrahepatic transfection. We employ novel biochemical characterization techniques to analyze nanoparticle protein corona formation with single-particle resolution and gain insight into the influence of protein adsorption on hepatic and splenic transfection. We evaluate a lead LNP candidate for therapeutic cancer vaccination in a syngeneic mouse model of melanoma and demonstrate a significant reduction in tumor burden and increase in survival compared to a clinical mRNA LNP formulation. Together, our results demonstrate the value of advanced LNP screening and characterization techniques for the development of next-generation mRNA therapeutics and vaccines.

bioengineering↗