LAUSR

Whether the immune imprinting caused by severe acute respiratory syndrome coronavirus (SARS‐CoV) affects the efficiency of SARS‐CoV‐2 vaccination has attracted global concern. Little is known about the dynamic changes of antibody response in SARS convalescents inoculated with three doses of inactivated SARS‐CoV‐2 vaccine although lack of cross‐neutralizing antibody response to SARS‐CoV‐2 in SARS survivors has been reported. We longitudinally examined the neutralizing antibodies (nAbs) against SARS‐CoV and SARS‐CoV‐2 as well as spikes binding IgA, IgG, IgM, IgG1, and IgG3 antibodies in 9 SARS‐recovered donors and 21 SARS‐naïve donors. Stably higher nAbs and spike antigens‐specific IgA, IgG antibodies against SARS‐CoV‐2 were observed in SARS‐recovered donors compared with SARS‐naïve donors during the period with two doses of BBIBP‐CorV vaccination. However, the third‐dose BBIBP‐CorV stimulated a sharply and shortly higher increase of nAbs in SARS‐naïve donors than in SARS‐recovered donors. It is worth noting that, regardless of prior SARS infection, the Omicron subvariants were found to subvert immune responses. Moreover, certain subvariants such as BA.2, BA.2.75, or BA.5 exhibited a high degree of immune evasion in SARS survivors. Interestingly, BBIBP‐CorV recalled higher nAbs against SARS‐CoV compared with SARS‐CoV‐2 in SARS‐recovered donors. In SARS survivors, a single dose of inactivated SARS‐CoV‐2 vaccine provoked immune imprinting for the SARS antigen, providing protection against wild‐type SARS‐CoV‐2, and the earlier variants of concern (VOCs) including Alpha, Beta, Gamma, and Delta but not against Omicron subvariants. As such, it is important to evaluate the type and dosage of SARS‐CoV‐2 vaccine for SARS survivors.