Immunoassay and mass cytometry revealed immunological profiles induced by inactivated BBIBP COVID‐19 vaccine

Abstract

With the global prevalence of COVID‐19 and the constant emergence of viral variants, boosters for COVID‐19 vaccines to enhance antibody titers in human bodies will become an inevitable trend. However, there is a lack of data on antibody levels and the protective effects of booster injections. This study monitored and analyzed the antibody potency and the antibody responses induced by the booster injection in the subjects who received three vaccine doses. The study was conducted in a multicenter collaboration and recruited 360 healthy adults aged 20–74. Participants received the first, second, and booster doses of inactivated Sinopharm/BBIBP COVID‐19 vaccine at 0, 1, and 7 months. Vaccine‐induced virus‐specific antibody levels (SARS‐COV‐2‐IgA/IgM/IgG) were monitored at multiple time points, surrogate virus neutralization test (sVNT), and the spatial distribution and proportion of immune cells and markers were analyzed using the CyTOF method before vaccination and a month after the second dose. The titers of SARS‐CoV‐2‐IgA/IgM/IgG and neutralizing antibodies increased to a high level in the first month after receiving the second dose of vaccine and declined slowly after that. The antibody levels of SARS‐CoV‐2‐IgG and sVNT were significantly increased at 0.5 months after the induction of the booster ( p < 0.05). Despite a downward trend, the antibody levels were still high in the following 6 months. The B cell concentration (in humoral sample) a month after the second injection was significantly reduced compared to that before the vaccine injection ( p < 0.05). The proportion of the C01 cell cluster was significantly decreased compared with that before vaccine injection ( p < 0.05). Individual cell surface markers showed distinctions in spatial distribution but were not significantly different. This study has shown that serum antibody titer levels will decrease with time by monitoring and analyzing the antibody efficacy and the antibody reaction caused by the booster injection of healthy people who received the whole vaccination (completed three injections). Still, the significant peak of the antibody titer levels after booster highlights the recall immune response. It can maintain a high concentration of antibody levels for a long time, which signifies that the protection ability has been enhanced following the injection of booster immunization. Additionally, CyTOF data shows the active production of antibodies and the change in the immunity environment.

Dynamic immunogenicity after primary and booster inactivated SARS‐CoV‐2 vaccination in people living with HIV: A longitudinal observational study

“…However, the antibody responses after BV in PLWH remain unknown. In this study, the antibody seroprevalence and titers were increased after booster inactivated vaccination in PLWH, and a similar phenomenon was observed in previous studies on mRNA vaccines in healthy population 19–22 . In detail, a third mRNA vaccine dose boosted the neutralization titer to an average of fourfold higher than 1 month after two dose levels in PLWH, which was similar to our results (3.7‐fold) 22 .…”

“…In this study, the antibody seroprevalence and titers were increased after booster inactivated vaccination in PLWH, and a similar phenomenon was observed in previous studies on mRNA vaccines in healthy population. [19][20][21][22] In detail, a third mRNA vaccine dose boosted the neutralization titer to an average of fourfold higher than 1 month after two dose levels in PLWH, which was similar to our results (3.7-fold). 22 However, a 27-fold higher antibody titer was observed 1 month after the third heterologous vaccine dose than that observed 6 months after two doses of ChAdOx1 nCoV-19 in PLWH, which was obviously higher than the results of this study (sixfold).…”

The humoral and cellular immune response of a third dose adenoviral-based vectored vaccine after a single or 2 shots of inactivated COVID-19 vaccine in healthy adults

“…This theory is supported by our data demonstrating that the inactivated vaccination can promote humoral immunity, reflected in the marked decline in B-cell counts. The recent study also demonstrated a similar result in the substantially reduced humoral B-cell levels measured using the CYTOF method in humans after a month of immunizing with the inactivated vaccine [26]. The specific SAR-CoV 2 antibody level was maintained for at least 6 months after vaccination with the inactivated vaccine [27].…”

Post-vaccination SARS-CoV-2 seroprevalence in children aged 3-11 years and the positivity in unvaccinated children: A retrospective, single-center study

“…The titers of SARS‐CoV‐2 IgG and neutralizing antibodies increased to high levels at the first month after receiving the second dose and declined slowly thereafter. The significant peak of the antibody titer levels after injection of the booster dose highlights the recall immune response ( 20 ). A study on children aged 3-12 years received two doses of inactivated SARS-CoV-2 vaccines in Bahrain showed that vaccination led to a promising immunogenicity.…”