Project description:SARS-CoV-2 variants with severe immune evasion are a major challenge for COVID-19 prevention, especially the circulating Omicron XBB/BQ.1.1/BF.7 strains. Thus, the next-generation of broad-spectrum vaccines are urgently needed. Previously, we developed a COVID-19 protein subunit vaccine, ZF2001, based on the RBD-homodimer as the immunogen. To adapt SARS-CoV-2 variants, we developed chimeric RBD-heterodimers to induce broad immune responses. In this study, we further explored the concept of tandem RBD homotrimer and heterotrimer. Prototype SARS-CoV-2 RBD-homotrimer, prototype-Delta-BA.1 (PDO) RBD-heterotrimer and Delta-BA.2-BA.5 (DBA2BA5) RBD-heterotrimer were designed. Biochemical and cryo-EM structural characterization demonstrated total epitope exposure of the RBD-trimers. In mouse experiments, PDO and DBA2BA5 elicited broad SARS-CoV-2 neutralization. Potent protection against SARS-CoV-2 variants was observed in challenge assays and was correlated with neutralizing antibody titer. This study validated the design strategy of tandem RBD-heterotrimers as multivalent immunogens and presented a promising vaccine candidate, DBA2BA5, eliciting broad-spectrum immune responses, including against the circulating XBB/BF.7/BQ.1.1.

| S-EPMC10538664 | biostudies-literature

BQ.1.1, XBB.1, and XBB.1.5 neutralization after bivalent mRNA COVID-19 booster in patients with cancer.

Project description:Ehmsen et al. evaluate the neutralizing capacity to current SARS-CoV-2 variants in patients with cancer before and after receiving the BNT162b2 bivalent mRNA vaccine booster. Bivalent vaccine provides some protection against BQ.1.1 but fails to protect against XBB.1 and XBB.1.5 in patients with cancer.

| S-EPMC9910012 | biostudies-literature

Neutralization of BQ.1, BQ.1.1, and XBB with RBD-Dimer Vaccines.

Project description: Not available

| S-EPMC10029362 | biostudies-literature

Omicron BQ.1.1 and XBB.1 unprecedentedly escape broadly neutralizing antibodies elicited by prototype vaccination.

Project description:Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariants have seriously attacked the antibody barrier established by natural infection and/or vaccination, especially the recently emerged BQ.1.1 and XBB.1. However, crucial mechanisms underlying the virus escape and the broad neutralization remain elusive. Here, we present a panoramic analysis of broadly neutralizing activity and binding epitopes of 75 monoclonal antibodies isolated from prototype inactivated vaccinees. Nearly all neutralizing antibodies (nAbs) partly or totally lose their neutralization against BQ.1.1 and XBB.1. We report a broad nAb, VacBB-551, that effectively neutralizes all tested subvariants including BA.2.75, BQ.1.1, and XBB.1. We determine the cryoelectron microscopy (cryo-EM) structure of VacBB-551 complexed with the BA.2 spike and perform detailed functional verification to reveal the molecular basis of N460K and F486V/S mutations mediating the partial escape of BA.2.75, BQ.1.1, and XBB.1 from the neutralization of VacBB-551. Overall, BQ.1.1 and XBB.1 raised the alarm over SARS-CoV-2 evolution with unprecedented antibody evasion from broad nAbs elicited by prototype vaccination.

| S-EPMC10201307 | biostudies-literature

Fourth mRNA vaccination increases cross-neutralizing antibody titers against SARS-CoV-2 variants, including BQ.1.1 and XBB, in a very elderly population.

Project description:BackgroundOmicron variants with immune evasion have emerged, and they continue to mutate rapidly, raising concerns about the weakening of vaccine efficacy, and the very elderly populations are vulnerable to Coronavirus Disease 2019 (COVID-19). Therefore, to investigate the effect of multiple doses of mRNA vaccine for the newly emerged variants on these populations, cross-neutralizing antibody titers were examined against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants, including BQ.1.1 and XBB.MethodsBlood samples were taken from residents at four long-term care facilities in Hyogo prefecture, Japan (median age, 91 years), after 3rd (n = 67) and 4th (n = 48) mRNA vaccinations, from April to October 2022. A live virus microneutralization assay was performed to determine the neutralizing antibody titers in participants' sera.ResultsAfter 3rd vaccination, cross-neutralizing antibody prevalence against conventional (D614G) virus, Delta, Omicron BA.2, BA.5, BA.2.75, BQ.1.1, and XBB were 100%, 97%, 81%, 51%, 67%, 4%, and 21%, respectively. After 4th vaccination, the antibody positivity rates increased to 100%, 100%, 98%, 79%, 92%, 31%, and 52%, respectively. The 4th vaccination significantly increased cross-neutralizing antibody titers against all tested variants.ConclusionThe positivity rates for BQ.1.1 and XBB increased after 4th vaccination, although the titer value was lower than those of BA.5 and BA.2.75. Considering the rapid mutation of viruses and the efficacy of vaccines, it may be necessary to create a system that can develop vaccines suitable for each epidemic in consideration of the epidemic of the virus.

| S-EPMC10163793 | biostudies-literature

Efficacy of Antiviral Agents against Omicron Subvariants BQ.1.1 and XBB.

Project description: Not available

| S-EPMC9749618 | biostudies-literature

Humoral immune evasion of the omicron subvariants BQ.1.1 and XBB.

Project description: Not available

| S-EPMC9729000 | biostudies-literature

Neutralization of SARS-CoV-2 Omicron BQ.1, BQ.1.1 and XBB.1 variants following SARS-CoV-2 infection or vaccination in children.

Project description:Emergence of highly transmissible Omicron subvariants led to increased SARS-CoV-2 infection and disease in children. However, minimal knowledge exists regarding the neutralization capacity against circulating Omicron BA.4/BA.5, BA.2.75, BQ.1, BQ.1.1 and XBB.1 subvariants following SARS-CoV-2 vaccination in children versus during acute or convalescent COVID-19, or versus multisystem inflammatory syndrome (MIS-C). Here, we evaluate virus-neutralizing capacity against SARS-CoV-2 variants in 151 age-stratified children ( <5, 5-11, 12-21 years old) hospitalized with acute severe COVID-19 or MIS-C or convalescent mild (outpatient) infection compared with 62 age-stratified vaccinated children. An age-associated effect on neutralizing antibodies is observed against SARS-CoV-2 following acute COVID-19 or vaccination. The primary series BNT162b2 mRNA vaccinated adolescents show higher vaccine-homologous WA-1 neutralizing titers compared with <12 years vaccinated children. Post-infection antibodies did not neutralize BQ.1, BQ.1.1 and XBB.1 subvariants. In contrast, monovalent mRNA vaccination induces more cross-neutralizing antibodies in young children <5 years against BQ.1, BQ.1.1 and XBB.1 variants compared with ≥5 years old children. Our study demonstrates that in children, infection and monovalent vaccination-induced neutralization activity is low against BQ.1, BQ.1.1 and XBB.1 variants. These findings suggest a need for improved SARS-CoV-2 vaccines to induce durable, more cross-reactive neutralizing antibodies to provide effective protection against emerging variants in children.

| S-EPMC10692185 | 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