| CoV | Coronavirus |
| DPP4 | Dipeptidyl peptidase-4 |
| ELISA | Enzyme-linked immunosorbent assay |
| i.d. | Intradermal |
| i.n. | Intranasal |
| LNPs | Lipid nanoparticles |
| MERS-CoV | Middle East respiratory syndrome CoV |
| RBD | Receptor-binding domain |
| S | Spike |
| SARS-CoV-2 | Severe acute respiratory syndrome CoV-2 |