The outbreak of SARS‐CoV‐2 Omicron lineages, immune escape, and vaccine effectivity

Journal of Medical Virology, Journal Year: 2022, Volume and Issue: 95(1)

Published: Sept. 13, 2022

As of November 2021, several SARS-CoV-2 variants appeared and became dominant epidemic strains in many countries, including five concern (VOCs) Alpha, Beta, Gamma, Delta, Omicron defined by the World Health Organization during COVID-19 pandemic. August 2022, is classified into main lineages, BA.1, BA.2, BA.3, BA.4, BA.5 some sublineages (BA.1.1, BA.2.12.1, BA.2.11, BA.2.75, BA.4.6) (https://www.gisaid.org/). Compared to previous VOCs (Alpha, Delta), all lineages have most highly mutations spike protein, with 50 accumulated throughout genome. Early data indicated that BA.2 sublineage had higher infectivity more immune escape than early wild-type (WT) strain, VOCs, BA.1. Recently, global surveillance suggest a transmissibility BA.4/BA.5 BA.1.1 becoming strain countries globally.

Language: Английский

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T Cell Responses to SARS-CoV-2

Annual Review of Immunology, Journal Year: 2023, Volume and Issue: 41(1), P. 343 - 373

Published: Feb. 8, 2023

A large body of evidence generated in the last two and a half years addresses roles T cells SARS-CoV-2 infection following vaccination. Infection or vaccination induces multi-epitope CD4 CD8 cell responses with polyfunctionality. Early have been associated mild COVID-19 outcomes. In concert animal model data, these results suggest that while antibody are key to prevent infection, may also play valuable reducing disease severity controlling infection. memory after is sustained for at least six months. While neutralizing impacted by variants, most preserved. This review highlights extensive progress made, data knowledge gaps remain, our understanding vaccines.

Language: Английский

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Cellular and humoral immune responses and breakthrough infections after three SARS-CoV-2 mRNA vaccine doses

Frontiers in Immunology, Journal Year: 2022, Volume and Issue: 13

Published: Aug. 17, 2022

SARS-CoV-2 vaccination has proven the most effective measure to control COVID-19 pandemic. Booster doses are being administered with limited knowledge on their need and effect immunity.To determine duration of specific T cells, antibodies neutralization after 2-dose vaccination, assess a third dose adaptive immunity explore correlates protection against breakthrough infection.12-month longitudinal assessment SARS-CoV-2-specific IgG neutralizing triggered by 2 BNT162b2 followed mRNA-1273 in cohort 77 healthcare workers: 17 infection prior (recovered) 60 naïve.Peak levels cellular humoral response were achieved weeks second dose. Antibodies declined thereafter while cells reached plateau 3 months vaccination. The decline was specially marked naïve individuals it this group who benefited from dose, which resulted 20.9-fold increase neutralization. Overall, recovered maintained higher 1 6 post-vaccination than naïve. Seventeen asymptomatic or mild infections reported during follow-up, only individuals. This viral exposure boosted immunity. High peak 15 days associated infections.Booster inclusion antigens other spike future vaccine formulations could be useful strategies prevent infections.

Language: Английский

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T‐cell responses to SARS‐CoV‐2 Omicron spike epitopes with mutations after the third booster dose of an inactivated vaccine

Journal of Medical Virology, Journal Year: 2022, Volume and Issue: 94(8), P. 3998 - 4004

Published: April 27, 2022

The rapidly spreading severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant contains more than 30 mutations that mediate escape from antibody responses elicited by prior infection or current vaccines. Fortunately, T-cell are highly conserved in most individuals, but the impacts of not clear. Here, we showed individuals who underwent booster vaccination with CoronaVac were largely protective against SARS-CoV-2 spike protein. To specifically estimate impact on vaccinated participants, 16 peptides derived protein ancestral virus strain used to stimulate peripheral blood mononuclear cells (PBMCs) volunteers. Compared administration two doses vaccine, substantially enhanced activation response both and epitopes, although enhancement was slightly weakened mutations. Then, these proteins separately PBMCs. Interestingly, compared peptides, only G339D N440K mutation detected significantly destabilize response. Although participants need be evaluated confirm this conclusion, our study nonetheless estimates variant.

Language: Английский

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Molecular aspects of Omicron, vaccine development, and recombinant strain XE: A review

Journal of Medical Virology, Journal Year: 2022, Volume and Issue: 94(10), P. 4628 - 4643

Published: June 16, 2022

The global pandemic of COVID-19 began in December 2019 and is still continuing. past 2 years have seen the emergence several variants that were more vicious than each other. Omicron (B.1.1.529) proved to be a huge epidemiological concern as rate infection this particular strain was enormous. identified South Africa on November 24, 2021 classified "Variant Concern" 26, 2021. variant possessed mutations key RBD region, S thereby increasing affinity ACE2 for better transmission virus. Antibody resistance found it able reduce vaccine efficiency vaccines. need booster brought forth due prevalence and, subsequently, led targeted research development variant-specific vaccines dosage. This review discusses broadly genomic characters features along with its specific mutations, evolution, antibody resistance, evasion, utilization CRISPR-Cas12a assay detection, T-cell immunity elicited by against Omicron, strategies decrease also XE recombinant infectivity BA.2 subvariant Omicron.

Language: Английский

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SARS-CoV-2 epitope-specific T cells: Immunity response feature, TCR repertoire characteristics and cross-reactivity

Frontiers in Immunology, Journal Year: 2023, Volume and Issue: 14

Published: March 10, 2023

The devastating COVID-19 pandemic caused by SARS-CoV-2 and multiple variants or subvariants remains an ongoing global challenge. SARS-CoV-2-specific T cell responses play a critical role in early virus clearance, disease severity control, limiting the viral transmission underpinning vaccine efficacy. Studies estimated broad robust each individual recognized at least 30 to 40 antigen epitopes associated with clinical outcome. Several key immunodominant proteome epitopes, including S protein- non-S protein-derived may primarily induce potent long-lasting antiviral protective effects. In this review, we summarized immune response features of epitope-specific cells targeting different SRAS-CoV-2 structures after infection vaccination, abundance, magnitude, frequency, phenotypic kinetics. Further, analyzed immunodominance hierarchy combination attributes TCR repertoires characteristics, discussed significant implications cross-reactive toward HCoVs, concern, especially Omicron. This review be essential for mapping landscape optimizing current strategy.

Language: Английский

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SARS-CoV-2 spike protein in infectivity

Elsevier eBooks, Journal Year: 2025, Volume and Issue: unknown, P. 21 - 56

Published: Jan. 1, 2025

Language: Английский

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Dynamic SARS-CoV-2-specific B-cell and T-cell responses induced in people living with HIV after a full course of inactivated SARS-CoV-2 vaccine

Frontiers in Immunology, Journal Year: 2025, Volume and Issue: 16

Published: Feb. 25, 2025

Both B-cell- and T-cell-mediated immunity are crucial for the effective clearance of viral infection, but little is known about dynamic characteristics SARS-CoV-2-specific B-cell T-cell responses in people living with HIV (PLWH) after a full course inactivated SARS-CoV-2 vaccination. In this study, fifty thirty healthy controls (HCs) were enrolled to assess at day before vaccination (T0), two weeks first dose (T1), months (T2), third (T3), one month (T4), three (T5) 12 (T6) dose. induced (PLWH), these lasted least year vaccine However, peak frequencies Spike-specific PLWH lower than those HIV-negative controls. addition, expansion activated B cells, memory cells plasma primary was observed, percentages decreased T6 comparable T0. Additionally, T exhausted enhanced functional activity increased following administration vaccine. had RBD-specific circulating Tfh (cTfh) CD38+ cTfh latter types positively correlated titer neutralizing antibodies, indicating differences may account weaker immune PLWH. These data suggest that specific could be sustained receiving Our findings emphasize weak have implications clinical decision-making public health policy respect infection.

Language: Английский

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The Immunogenicity of CpG, MF59-Like, and Alum Adjuvant Delta Strain Inactivated SARS-CoV-2 Vaccines in Mice

Vaccines, Journal Year: 2024, Volume and Issue: 12(1), P. 60 - 60

Published: Jan. 7, 2024

The continuous evolution and mutation of SARS-CoV-2 have highlighted the need for more effective vaccines. In this study, CpG, MF59-like, Alum adjuvant Delta strain inactivated vaccines were prepared, immunogenicity these in mice was evaluated. + MF59-like vaccine group produced highest levels S- RBD-binding antibodies live virus neutralization after one shot immunization, while had two doses, groups high cross-neutralization against prototype, Beta, Gamma viruses. There no significant decrease neutralizing antibody any during observation period. excited different subtypes compared with unadjuvanted vaccines; CpG a higher proportion IgG2b antibodies, indicating bias towards Th1 immunity. proportions IgG1 similar to those vaccine. However, Th2 Antigen-specific cytokine secretion CD4/8+ T cells analyzed. conclusion, results study show differences immune efficacy mice, which implications selection strategy adjuvants.

Language: Английский

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Interleukin‐2‐mediated CD4 T‐cell activation correlates highly with effective serological and T‐cell responses to SARS‐CoV‐2 vaccination in people living with HIV

Journal of Medical Virology, Journal Year: 2024, Volume and Issue: 96(8)

Published: July 26, 2024

People living with HIV (PLWH) despite having an appreciable depletion of CD4

Language: Английский

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