TY - JOUR
T1 - Exosome-mediated mRNA delivery in vivo is safe and can be used to induce SARS-CoV-2 immunity
AU - Tsai, Shang Jui
AU - Atai, Nadia A.
AU - Cacciottolo, Mafalda
AU - Nice, Justin
AU - Salehi, Arjang
AU - Guo, Chenxu
AU - Sedgwick, Alanna
AU - Kanagavelu, Saravana
AU - Gould, Stephen J.
N1 - Funding Information:
Acknowledgments—We thank Omid Sheikh for outstanding technical assistance during the course of these studies. This study was conducted with support from Capricor and from Johns Hopkins University. We thank Andrea Cox and Guido Massaccesi for access to IRB-acquired and de-identified plasmas from patients with COVID-19.
Publisher Copyright:
© 2021 American Society for Biochemistry and Molecular Biology Inc.. All rights reserved.
PY - 2021/11/1
Y1 - 2021/11/1
N2 - Functional delivery of mRNA has high clinical potential. Previous studies established that mRNAs can be delivered to cells in vitro and in vivo via RNA-loaded lipid nanoparticles (LNPs). Here we describe an alternative approach using exosomes, the only biologically normal nanovesicle. In contrast to LNPs, which elicited pronounced cellular toxicity, exosomes had no adverse effects in vitro or in vivo at any dose tested. Moreover, mRNA-loaded exosomes were characterized by efficient mRNA encapsulation (_90%), high mRNA content, consistent size, and a polydispersity index under 0.2. Using an mRNA encoding the red light-emitting luciferase Antares2, we observed that mRNA-loaded exosomes were superior to mRNA-loaded LNPs at delivering functional mRNA into human cells in vitro. Injection of Antares2 mRNA-loaded exosomes also led to strong light emission following injection into the vitreous fluid of the eye or into the tissue of skeletal muscle in mice. Furthermore, we show that repeated injection of Antares2 mRNA-loaded exosomes drove sustained luciferase expression across six injections spanning at least 10 weeks, without evidence of signal attenuation or adverse injection site responses. Consistent with these findings, we observed that exosomes loaded with mRNAs encoding immunogenic forms of the SARS-CoV-2 Spike and Nucleocapsid proteins induced long-lasting cellular and humoral responses to both. Taken together, these results demonstrate that exosomes can be used to deliver functional mRNA to and into cells in vivo.
AB - Functional delivery of mRNA has high clinical potential. Previous studies established that mRNAs can be delivered to cells in vitro and in vivo via RNA-loaded lipid nanoparticles (LNPs). Here we describe an alternative approach using exosomes, the only biologically normal nanovesicle. In contrast to LNPs, which elicited pronounced cellular toxicity, exosomes had no adverse effects in vitro or in vivo at any dose tested. Moreover, mRNA-loaded exosomes were characterized by efficient mRNA encapsulation (_90%), high mRNA content, consistent size, and a polydispersity index under 0.2. Using an mRNA encoding the red light-emitting luciferase Antares2, we observed that mRNA-loaded exosomes were superior to mRNA-loaded LNPs at delivering functional mRNA into human cells in vitro. Injection of Antares2 mRNA-loaded exosomes also led to strong light emission following injection into the vitreous fluid of the eye or into the tissue of skeletal muscle in mice. Furthermore, we show that repeated injection of Antares2 mRNA-loaded exosomes drove sustained luciferase expression across six injections spanning at least 10 weeks, without evidence of signal attenuation or adverse injection site responses. Consistent with these findings, we observed that exosomes loaded with mRNAs encoding immunogenic forms of the SARS-CoV-2 Spike and Nucleocapsid proteins induced long-lasting cellular and humoral responses to both. Taken together, these results demonstrate that exosomes can be used to deliver functional mRNA to and into cells in vivo.
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U2 - 10.1016/j.jbc.2021.101266
DO - 10.1016/j.jbc.2021.101266
M3 - Article
C2 - 34600888
AN - SCOPUS:85120061351
SN - 0021-9258
VL - 297
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 5
M1 - 101266
ER -