Publications by authors named "Laura Silva-Reyes"

Article Synopsis
  • - Adenoviral-vectored vaccines have been successfully used for SARS-CoV-2 and Ebola, but their effectiveness for bacterial proteins can be affected by how these proteins are expressed in eukaryotic cells, leading to issues like incorrect localization or glycosylation.
  • - In this study, researchers explored using an adenoviral-vectored vaccine for capsular group B meningococcus (MenB) by creating candidates expressing the MenB antigen fHbp, which showed strong antigen-specific antibody and T cell responses in mice.
  • - The optimized vaccine candidate, which included a genetic modification to improve its effectiveness in humans, has moved into clinical development, demonstrating the potential of genetic vaccines in generating effective immune responses against bacterial
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Q fever is a highly infectious zoonosis caused by the Gram-negative bacterium Coxiella burnetii. The worldwide distribution of Q fever suggests a need for vaccines that are more efficacious, affordable, and does not induce severe adverse reactions in vaccine recipients with pre-existing immunity against Q fever. Potential Q fever vaccine antigens include lipopolysaccharide (LPS) and several C.

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Article Synopsis
  • The study examines the immune responses in UK healthcare workers after vaccination with BNT162b2 or AZD1222, focusing on the effects of prior SARS-CoV-2 infection on these responses.
  • Over 6-9 months, researchers found that while antibody levels declined, T and memory B cell responses remained stable; booster doses effectively increased antibody levels and enhanced immunity against variants.
  • Prior infection significantly enhanced T cell responses, which persisted for at least six months after vaccination, indicating that "hybrid" immunity (from both infection and vaccination) may lead to better protection against severe illness.
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The clinical development of the meningococcal vaccine, 4CMenB, included 2 doses in vaccine-naïve adolescents, which was considered unlikely to be cost-effective for implementation. Theoretically, priming with 4CMenB in early childhood might drive strong immune responses after only a single booster dose in adolescents and reduce programmatic costs. To address this question, children over 11 years old who took part in previous trials involving the administration of 3-5 doses of 4CMenB at infant/preschool age from 2006 were recruited into a post licensure single-centre trial, and were divided into two groups: those who received their last dose at 12 months old (infant group) and those who received their last dose at 3 years old (infant + preschool group).

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Background: Disease caused by the capsular group B meningococcus (MenB) is the leading cause of infectious death in UK infants. A novel adenovirus-based vaccine encoding the MenB factor H binding protein (fHbp) with an N-terminal dual signal sequence induces high titres of protective antibody after a single dose in mice. A panel of N-terminal signal sequence variants were created to assess the contribution of components of this sequence to transgene expression kinetics of the encoded antigen from mammalian cells and the resultant effect on immunogenicity of fHbp.

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Article Synopsis
  • * Researchers selected human HLA class II T cell epitopes based on predictive analyses and past exposure data from a Q fever outbreak, aiming to create vaccine candidates that minimize potential side effects.
  • * Initial tests in guinea pigs showed no adverse reactions, but while some efficacy was observed in mice, it was insufficient for protection against infection; however, the vaccine did create a strong immune response in macaques, setting the stage for further efficacy trials.
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Article Synopsis
  • A study was conducted on UK healthcare workers from April to June 2020 to explore how acquired immunity to COVID-19 develops, particularly before vaccines were available.
  • The researchers found that immune responses to the virus varied widely among participants, with some immune markers decreasing over time while others remained stable.
  • A subgroup of individuals displayed stronger immune responses, which correlated with long-term protection against severe disease from COVID-19 and its variants.
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Vδ2 γδT cells are unconventional T cells that can be activated by cytokines without TCR signaling. Adenovirus vaccine vectors activated Vδ2 γδT cells in an interleukin 18-, TNF-, and type I interferon-dependent manner. This stimulatory capacity was associated with adenovirus vectors of non-species C origin, including the ChAdOx1 vaccine platform.

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Extension of the interval between vaccine doses for the BNT162b2 mRNA vaccine was introduced in the United Kingdom to accelerate population coverage with a single dose. At this time, trial data were lacking, and we addressed this in a study of United Kingdom healthcare workers. The first vaccine dose induced protection from infection from the circulating alpha (B.

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Mucosal-associated invariant T (MAIT) cells are innate sensors of viruses and can augment early immune responses and contribute to protection. We hypothesized that MAIT cells may have inherent adjuvant activity in vaccine platforms that use replication-incompetent adenovirus vectors. In mice and humans, ChAdOx1 (chimpanzee adenovirus Ox1) immunization robustly activated MAIT cells.

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  • The study evaluated the safety and efficacy of an investigational RSV vaccine (ChAd155-RSV) in healthy adults aged 18-45 through a Phase I clinical trial comparing it to a placebo and an active control.
  • Participants received either a low or high dose of the vaccine, and assessments included adverse events and immune responses, showing no serious side effects and notable increases in neutralizing antibodies against RSV.
  • The results suggest that the ChAd155-RSV vaccine can induce specific humoral and T-cell immunity in individuals with prior RSV exposure, warranting further investigation.
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Article Synopsis
  • Salmonella Typhi causes typhoid fever, affecting about 10.9 million people each year.
  • Researchers studied the effects of a specific part of the bacteria called typhoid toxin on healthy volunteers who were given either normal bacteria or a version without the toxin.
  • They found that having the toxin didn't really change the infection rate or early symptoms of typhoid fever, but it did make the bacteria stay in the blood longer for some people.
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Objectives: Respiratory syncytial virus (RSV) causes respiratory infection across the world, with infants and the elderly at particular risk of developing severe disease and death. The replication-defective chimpanzee adenovirus (PanAd3-RSV) and modified vaccinia virus Ankara (MVA-RSV) vaccines were shown to be safe and immunogenic in young healthy adults. Here we report an extension to this first-in-man vaccine trial to include healthy older adults aged 60-75 years.

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Background: Zika virus (ZIKV) has become a global threat with immediate need for accurate diagnostics, efficacious vaccines and therapeutics. Several ZIKV envelope (Env)-based vaccines have been developed recently. However, many commercially available ZIKV Env are based on the African lineage and produced in insect cells.

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Importance: Developing effective vaccines against Ebola virus is a global priority.

Objective: To evaluate an adenovirus type 26 vector vaccine encoding Ebola glycoprotein (Ad26.ZEBOV) and a modified vaccinia Ankara vector vaccine, encoding glycoproteins from Ebola virus, Sudan virus, Marburg virus, and Tai Forest virus nucleoprotein (MVA-BN-Filo).

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