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Hood, E. D.

Publications and source records attributed to Hood, E. D..

2 recordsLinked to original sources

Targeting DNA-LNPs to Endothelial Cells Improves Expression Magnitude, Duration, and Specificity

DNA-lipid nanoparticles (DNA-LNPs) loaded with inhibitors of the cGAS-STING pathway enable safe and effective delivery of DNA in vivo. Herein, we report the first instances of extrahepatic DNA-LNP targeting. DNA-LNPs conjugated to antibodies against PECAM-1 or VCAM-1 target the endothelium of the lungs and brain/spleen, respectively. These LNPs drive robust transgene expression in their target organs, with greater magnitude and duration than untargeted LNPs. Lung specificity of PECAM-targeted transgene expression increases over two weeks, resulting in markedly higher lung-to-liver expression ratios than our previous PECAM-targeted mRNA-LNPs. Off-target liver DNA expression declines to undetectable levels but persists in the lungs, while mRNA expression uniformly decreases due to its short half-life. We further improve this expression specificity by replacing full-length antibodies with Fab fragments. Single-cell analysis reveals a key mechanism underlying the improvements in organ-specificity: target organ expression is dominated by long-lived endothelial cells, while off-target liver delivery and expression are in non-endothelial cells with shorter half-lives. Collectively, these studies demonstrate that targeted DNA-LNPs achieve high levels of organ- and cell-type-specific transgene expression and thus provide a therapeutic platform for dozens of endothelial-centric diseases.

bioengineering↗

Supramolecular Organization Predicts Protein Nanoparticle Delivery to Neutrophils for Acute Lung Inflammation Diagnosis and Treatment

Acute lung inflammation has severe morbidity, as seen in COVID-19 patients. Lung inflammation is accompanied or led by massive accumulation of neutrophils in pulmonary capillaries ("margination"). We sought to identify nanostructural properties that predispose nanoparticles to accumulate in pulmonary marginated neutrophils, and therefore to target severely inflamed lungs. We designed a library of nanoparticles and conducted an in vivo screen of biodistributions in naive mice and mice treated with lipopolysaccharides. We found that supramolecular organization of protein in nanoparticles predicts uptake in inflamed lungs. Specifically, nanoparticles with agglutinated protein (NAPs) efficiently home to pulmonary neutrophils, while protein nanoparticles with symmetric structure (e.g. viral capsids) are ignored by pulmonary neutrophils. We validated this finding by engineering protein-conjugated liposomes that recapitulate NAP targeting to neutrophils in inflamed lungs. We show that NAPs can diagnose acute lung injury in SPECT imaging and that NAP-like liposomes can mitigate neutrophil extravasation and pulmonary edema arising in lung inflammation. Finally, we demonstrate that ischemic ex vivo human lungs selectively take up NAPs, illustrating translational potential. This work demonstrates that structure-dependent interactions with neutrophils can dramatically alter the biodistribution of nanoparticles, and NAPs have significant potential in detecting and treating respiratory conditions arising from injury or infections.

bioengineering↗