Preventing SARS-CoV-2 Infection Using Anti-spike Nanobody-IFN-β Conjugated Exosomes

Abstract

Purpose To inhibit the transmission of SARS-CoV-2, we developed engineered exosomes that were conjugated with anti-spike nanobodies and type I interferon β (IFN-β). We evaluated the efficacy and potency of nanobody-IFN-β conjugated exosomes to treatment of SARS-CoV-2 infection . Methods Milk fat globule epidermal growth factor 8 (MFG-E8) is a glycoprotein that binds to phosphatidylserine (PS) exposed on the exosomes. We generated nanobody-IFN-β conjugated exosomes by fusing an anti-spike nanobody and IFN-β with MFG-E8. We used the SARS-CoV-2 pseudovirus with the spike of the D614G mutant that encodes ZsGreen to mimic the infection process of the SARS-CoV-2. The SARS-CoV-2 pseudovirus was infected with angiotensin-converting enzyme-2 (ACE2) expressing adenocarcinomic human alveolar basal epithelial cells (A549) or ACE2 expressing HEK-blue IFNα/β cells in the presence of nanobody-IFN-β conjugated exosomes. By assessing the expression of ZsGreen in target cells and the upregulation of interferon-stimulated genes (ISGs) in infected cells, we evaluated the anti-viral effects of nanobody-IFN-β conjugated exosomes. Results We confirmed the anti-spike nanobody and IFN-β expressions on the exosomes. Exosomes conjugated with nanobody-hIFN-β inhibited the interaction between the spike protein and ACE2, thereby inhibiting the infection of host cells with SARS-CoV-2 pseudovirus. At the same time, IFN-β was selectively delivered to SARS-CoV-2 infected cells, resulting in the upregulation of ISGs expression. Conclusion Exosomes conjugated with nanobody-IFN-β may provide potential benefits in the treatment of COVID-19 because of the cooperative anti-viral effects of the anti-spike nanobody and the IFN-β. Supplementary Information The online version contains supplementary material available at 10.1007/s11095-022-03400-0.

Understanding the Molecular Actions of Spike Glycoprotein in SARS-CoV-2 and Issues of a Novel Therapeutic Strategy for the COVID-19 Vaccine

“…Meanwhile, modified extracellular vesicles (EVs) loaded with nanobodies against the spike protein of SARS-CoV-2 and interferon-beta, a cytokine with antiviral effects, have been reported [61][62][63][64]. EVs are biological substances with a heterogenous lipid bilayer structure that are secreted from almost all living cells and broadly classified into three types: exosomes, microvesicles, and apoptotic bodies, depending on the intracellular production mechanism [65][66][67].…”

A comprehensive review of engineered exosomes from the preparation strategy to therapeutic applications

“…of exosomes), thereby preventing SARS-CoV-2 infection. 60 The aforementioned research demonstrates that genetic engineering technology can not only successfully establish highly targeted engineered exosomes but also significantly enhance the drug loading capacity of these engineered exosomes. This advancement enables more precise and effective treatment approaches.…”

“…generated nanobody-IFN-β conjugated exosomes by fusing anti-spike nanobodies and type I interferon (IFN-β) with milk fat globule epidermal growth factor 8 (a glycoprotein that binds to phosphatidylserine exposed on the surface of exosomes), thereby preventing SARS-CoV-2 infection. 60 The aforementioned research demonstrates that genetic engineering technology can not only successfully establish highly targeted engineered exosomes but also significantly enhance the drug loading capacity of these engineered exosomes. This advancement enables more precise and effective treatment approaches.…”

Current development of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies (Review)

“…In addition, researchers have engineered exosomes with a S-protein-targeting Nb and human IFN-β bound to MFG-E8, creating a dual-action system. The Nbs on the exosome surface bind to the SARS-CoV-2 S protein, blocking its entry into host cells, while the encapsulated IFN-β is delivered to infected cells to trigger antiviral responses and boost the expression of interferon-stimulated genes ( 166 ). In summary, further exploration of antibody engineering is justified to improve the neutralization capacity of available antibodies.…”