A vesicle-based immunogen.
Potential treatment - pre-clinical evidence
Exosomes are a class of nano-sized cell-derived extracellular vesicles. They carry various types of natural or engineered cellular components or substances (Zhang et al., 2020). The term “exosomal vaccine” may refer to various cell-derived products whose biological activity is based on exosomal delivery of an immunogenic substance. Shen et al. (2022) showed the immunogenic potential of exosomes loaded with T cell epitope peptides derived from SARS-CoV-2 in mice. Wang et al. (2022) loaded lung-derived exosomes with recombinant SARS-CoV-2 receptor-binding domain. They showed the formulation’s efficacy in a SARS-CoV-2 pseudovirus challenge in a murine mode and in a SARS-CoV-2 live virus challenge in a hamster model.
Exosomal Vaccine Loading T Cell Epitope Peptides of SARS-CoV-2 Induces Robust CD8+ T Cell Response in HLA-A Transgenic Mice
Spike protein RdRpol Envelope protein Nucleocapsid protein Membrane protein Cell-based therapy Novel compound Animal model Mixed substance Extracellular vesicles
|"A patient with blastic plasmacytoid dendritic cell neoplasm"
Red blood cell-derived exosomes were loaded with SARS-CoV-2-derived peptides conjugated to molecules with affinity to lipides, which were previously found to be presented by human leukocyte antigen A0201 molecule. The formulation induced a CD8+ T cell response in mice without visible organ toxicity.
Exosomes decorated with a recombinant SARS-CoV-2 receptor-binding domain as an inhalable COVID-19 vaccine
Spike protein Cell-based therapy Novel compound Animal model In vitro Mixed substance Extracellular vesicles
|In vitro; male CD1 mice; Syrian golden hamsters
Lung cell-derived exosomes were conjugated with SARS-CoV-2 recombinant SARS-CoV-2 receptor-binding domain. The inhaled formulation induced a systematic immune response in mice, including mucosal IgA and lung T cell responses. It was shown to attenuate severe pneumonia and reduce inflammatory infiltrates in hamsters after a viral challenge. The exosomes were stable during storage.