Project description:The emergence of the new SARS-CoV-2 Omicron variant, which is known to accumulate a huge number of mutations when compared to other variants, brought to light the concern about vaccine escape, especially from the neutralization by antibodies induced by vaccination. In this scenario, we evaluated the impact on antibody neutralization induction, against Omicron variant, by a booster dose of BNT162b2 mRNA vaccine after the CoronaVac primary vaccination scheme. The percentage of seroconverted individuals 30 and 60 days after CoronaVac scheme was 17% and 10%, respectively. After booster dose administration, the seroconvertion rate increased to 76.6%. The neutralization mean titer against Omicron in the CoronaVac protocol decreased over time, but after the booster dose, the mean titer increased 43.1 times, indicating a positive impact of this vaccine combination in the serological immune response.

| S-EPMC8963699 | biostudies-literature

Neutralization of SARS-CoV-2 omicron after BBIBP-CorV and ZF2001 booster vaccination.

Project description: Not available

| S-EPMC9762096 | biostudies-literature

Heterologous mRNA vaccine booster increases neutralization of SARS-CoV-2 Omicron BA.2 variant.

Project description: Not available

| S-EPMC9295091 | biostudies-literature

Extensive neutralization against SARS-CoV-2 variants elicited by Omicron-specific subunit vaccine as a heterologous booster.

Project description:To overcome the increased risk of SARS-CoV-2 reinfection or post-vaccination infection caused by the Omicron variant, Omicron-specific vaccines were considered a potential strategy. We reported the increased magnitude and breadth of antibody response against VOCs elicited by post-vaccination Delta and Omicron infection, compared to WT infection without vaccination. Then, in mouse models, three doses of Omicron-RBD immunization elicited comparable neutralizing antibody (NAb) titers with three doses of WT-RBD immunization, but the neutralizing activity was not cross-active. By contrast, a heterologous Omicron-RBD booster following two doses of WT-RBD immunization increased the NAb titers against Omicron by 9-folds than the homologous WT-RBD booster. Moreover, it retains neutralization against both WT and current VOCs. Results suggest that Omicron-specific subunit booster shows its advantages in the immune protection from both WT and current VOCs and that SARS-CoV-2 vaccines including two or more virus lineages might improve the NAb response.

| S-EPMC9621588 | biostudies-literature

SARS-CoV-2 Omicron Variant Neutralization after Third Dose Vaccination in PLWH.

Project description:The aim was to measure neutralizing antibody levels against the SARS-CoV-2 Omicron (BA.1) variant in serum samples obtained from vaccinated PLWH and healthcare workers (HCW) and compare them with those against the Wuhan-D614G (W-D614G) strain, before and after the third dose of a mRNA vaccine. We included 106 PLWH and 28 HCWs, for a total of 134 participants. Before the third dose, the proportion of participants with undetectable nAbsT against BA.1 was 88% in the PLWH low CD4 nadir group, 80% in the high nadir group and 100% in the HCW. Before the third dose, the proportion of participants with detectable nAbsT against BA.1 was 12% in the PLWH low nadir group, 20% in the high nadir group and 0% in HCW, respectively. After 2 weeks from the third dose, 89% of the PLWH in the low nadir group, 100% in the high nadir group and 96% of HCW elicited detectable nAbsT against BA.1. After the third dose, the mean log2 nAbsT against BA.1 in the HCW and PLWH with a high nadir group was lower than that seen against W-D614G (6.1 log2 (±1.8) vs. 7.9 (±1.1) and 6.4 (±1.3) vs. 8.6 (±0.8)), respectively. We found no evidence of a different level of nAbsT neutralization by BA.1 vs. W-D614G between PLWH with a high CD4 nadir and HCW (0.40 (−1.64, 2.43); p = 0.703). Interestingly, in PLWH with a low CD4 nadir, the mean log2 difference between nAbsT against BA.1 and W-D614G was smaller in those with current CD4 counts 201−500 vs. those with CD4 counts < 200 cells/mm3 (−0.80 (−1.52, −0.08); p = 0.029), suggesting that in this target population with a low CD4 nadir, current CD4 count might play a role in diversifying the level of SARS-CoV-2 neutralization.

| S-EPMC9415025 | biostudies-literature

mRNA booster vaccination protects aged mice against the SARS-CoV-2 Omicron variant.

Project description:The SARS-CoV-2 Omicron variant evades vaccine-induced immunity. While a booster dose of ancestral mRNA vaccines effectively elicits neutralizing antibodies against variants, its efficacy against Omicron in older adults, who are at the greatest risk of severe disease, is not fully elucidated. Here, we evaluate multiple longitudinal immunization regimens of mRNA BNT162b2 to assess the effects of a booster dose provided >8 months after the primary immunization series across the murine lifespan, including in aged 21-month-old mice. Boosting dramatically enhances humoral and cell-mediated responses with evidence of Omicron cross-recognition. Furthermore, while younger mice are protected without a booster dose, boosting provides sterilizing immunity against Omicron-induced lung infection in aged 21-month-old mice. Correlational analyses reveal that neutralizing activity against Omicron is strongly associated with protection. Overall, our findings indicate age-dependent vaccine efficacy and demonstrate the potential benefit of mRNA booster immunization to protect vulnerable older populations against SARS-CoV-2 variants.

| S-EPMC9357006 | biostudies-literature

Serum Neutralization of SARS-CoV-2 Omicron BA.1 and BA.2 after BNT162b2 Booster Vaccination.

Project description:The SARS-CoV-2 Omicron variant BA.2 sublineage is rapidly replacing earlier Omicron lineages, suggesting BA.2 has increased vaccine evasion properties. We measured neutralization titers of authentic BA.1 and BA.2 isolates in serum samples from persons who received the BNT162b2 booster vaccine. All samples neutralized BA.1 and BA.2 at equal median values.

| S-EPMC9155893 | biostudies-literature

Maternal and Neonatal SARS-CoV-2 Omicron Variant Neutralization after Antenatal mRNA Vaccination.

Project description:We evaluated the neutralization efficiency against SARS-CoV-2 omicron variant in maternal and cord blood sera after antenatal BNT162b2 vaccination. Neutralizing antibodies against omicron were lacking at the time of delivery after two-dose vaccination. A third booster dose was essential in building neutralizing antibody capacity against omicron among mothers and neonates.

| S-EPMC9213860 | biostudies-literature

Increased resistance of SARS-CoV-2 Omicron variant to neutralization by vaccine-elicited and therapeutic antibodies.

Project description:BackgroundSARS-CoV-2 vaccines currently authorized for emergency use have been highly successful in preventing infection and lessening disease severity. The vaccines maintain effectiveness against earlier SARS-CoV-2 Variants of Concern but the heavily mutated, highly transmissible Omicron variant presents an obstacle both to vaccine protection and monoclonal antibody therapies.MethodsPseudotyped lentiviruses were incubated with serum from vaccinated and boosted donors or therapeutic monoclonal antibody and then applied to target cells. After 2 days, luciferase activity was measured in a microplate luminometer. Resistance mutations of the Omicron spike were identified using point-mutated spike protein pseudotypes and mapped onto the three-dimensional spike protein structure.FindingsVirus with the Omicron spike protein was 26-fold resistant to neutralization by recovered donor sera and 26-34-fold resistance to Pfizer BNT162b2 and Moderna vaccine-elicited antibodies following two immunizations. A booster immunization increased neutralizing titres against Omicron. Neutralizing titres against Omicron were increased in the sera with a history of prior SARS-CoV-2 infection. Analysis of the therapeutic monoclonal antibodies showed that the Regeneron and Eli Lilly monoclonal antibodies were ineffective against the Omicron pseudotype while Sotrovimab and Evusheld were partially effective.InterpretationThe results highlight the benefit of a booster immunization to protect against the Omicron variant and demonstrate the challenge to monoclonal antibody therapy. The decrease in neutralizing titres against Omicron suggest that much of the vaccine efficacy may rely on T cells.FundingThe work was funded by grants from the NIH to N.R.L. (DA046100, AI122390 and AI120898) and 55 to M.J.M. (UM1AI148574).

| S-EPMC9021600 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data