have been developed since the outbreak of SARS, the majority of which use the S protein and/or its antigenic fragments, in particular, RBD, as the vaccine target (Table 1).
TABLE 1  Subunit Vaccines against SARS-CoVa.
Name  Antigenicity and functionality  Adjuvant  Route  Animal models  Antibody response  Cellular immune response  Protection  References
Subunit vaccines based on SARS-CoV full-length or trimeric S protein
FL-S and EC-S proteins  Bind to SARS-CoV S1, NTD, RBD, and S2-specific mAbs  MPL + TDM  S.C.  BALB/c mice  Elicit SARS-CoV S-specific Abs (Ig