PROS1 and infection: As expected, our recruited donors who have received two or three doses of inactivated SARS-CoV-2 vaccines (p=0.011) and who experienced BA.5/BF.7 breakthrough infection (p<0.001) showed significantly higher level of ELISA reactivity against the S protein of SARS-CoV-2, compared with the unexposed (unvaccinated and uninfected) donors (Figure 1C).