Neutralizing antibody titres to SARS-CoV-2 Omicron variant and wild-type virus in those with past infection or vaccinated or boosted with mRNA BNT162b2 or inactivated CoronaVac vaccines

Abstract

Omicron, a novel SARS-CoV-2 variant has emerged and is rapidly becoming the dominant SARS-CoV-2 virus circulating globally. It is important to define reductions in virus neutralizing activity in serum of convalescent or vaccinated individuals to understand potential loss of protection from infection or re-infection. Two doses of BNT162b2 or CoronaVac vaccines provided little 50% plaque reduction neutralization test (PRNT50) antibody immunity against the Omicron variant, even at one-month post vaccination. Booster doses with BNT162b2 in those with two doses of either BNT162b2 or CoronaVac provided acceptable neutralizing immunity against Omicron variant at 1-month post-booster dose. However, three doses of BNT162b2 elicited higher levels of PRNT50 antibody to Omicron variant suggesting longer duration of protection. Convalescent from SARS-CoV-2 infection did not have protective PRNT50 antibody levels to Omicron, but a single dose of BNT162b2 vaccine provided protective immunity. Field vaccine-efficacy studies against Omicron variant against different vaccines are urgently needed.

Multiple sclerosis disease-modifying therapies and COVID-19 vaccines: A practical review and meta-analysis

“…Additionally, as heterologous boosters among healthy people showed to be more immunogenic and effective 74 , further replication among pwMS with heterologous regimens is encouraged, especially among the ones primed with inactivated vaccines – as samples from inactivated-vaccinated people show less neutralizing activity against the Omicron variant 75 , and the heterologous boosters with superiority of mRNA 13,14,76-78 over AV 79 have shown to be more immunogenic than homologous boosters in healthy people receiving inactivated priming regimens.…”

In Silico Screening of Bioactive Compounds of Representative Seaweeds to Inhibit SARS-CoV-2 ACE2-Bound Omicron B.1.1.529 Spike Protein Trimer

“…Among that, 17 mutations such as Leu371, Pro373, Phe375, Tyr396, Asp339, Lys440, Trp353, Asn417, His505, Tyr501, Arg493, Ser496, Arg498, Ser446, Ala484, Lys478, and Asn477 are reported in the RBD (Figure 1). These amino acid substitutions might have a major impact on transmission and evasion of neutralizing mAbs, including BNT162b2, PiCoVacc, and AZD1222 vaccines [57,58]. In addition, the Ligplot interactions between the RBD of omicron B.1.1.529 spike protein and the selected compounds such as cefuroxime, TPBT, CMBA, syringaresinol, caffeic acid hexoside, and phloretin are depicted in Figure 3.…”

“…Among that, 17 mutations such as Leu371, Pro373, Phe375, Tyr396, Asp339, Lys440, Trp353, Asn417, His505, Tyr501, Arg493, Ser496, Arg498, Ser446, Ala484, Lys478, and Asn477 are reported in the RBD (Figure 1). These amino acid substitutions might have a major impact on transmission and evasion of neutralizing mAbs, including BNT162b2, PiCoVacc, and AZD1222 vaccines [57,58].…”

SARS-CoV-2 Spike and Neutralizing Antibody Kinetics 90 Days after Three Doses of BNT162b2 mRNA COVID-19 Vaccine in Singapore

“…Several studies have demonstrated a brisk antibody response to the booster vaccination [2][3][4][5], with some titers even higher than post-infection levels [3]. Booster vaccination has been shown to be effective against several different SARS-CoV-2 variants, including the new Omicron variant [6][7][8], and tolerated well with minimal side effects [9]. Indeed, booster vaccination regimens have been beneficial in controlling the spread of SARS-CoV-2, with real-world analysis [10] showing that it can reduce the rates of COVID-19 by a factor of 11.3, and severe illness by a factor of 19.5.…”