Publications by authors named "Grace H Rafael"

Article Synopsis
  • First-generation COVID-19 vaccines based on the spike (S) protein have decreased in effectiveness against new Omicron variants, highlighting the need for more broadly protective vaccines.
  • Researchers developed a new mRNA vaccine targeting the nucleocapsid (N) protein and tested its efficacy alone and in combination with the existing S-based vaccine in hamsters.
  • Results showed that the combined mRNA vaccines (mRNA-S+N) provided complete protection against Omicron variants, suggesting their potential as a comprehensive COVID-19 vaccine.
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Article Synopsis
  • The Omicron subvariant BA.5 became the dominant strain globally, surpassing earlier subvariants due to its ability to evade immune responses and bind more effectively to receptors.
  • A study using male Syrian hamsters assessed how well different COVID-19 vaccine regimens, including Janssen and Pfizer/BioNTech vaccines, protect against BA.5 after primary vaccination and boosters.
  • Results showed that a single high or low dose of the Janssen vaccine offers longer-lasting immunity compared to two doses of Pfizer, and boosters like Novavax enhance immunity and reduce viral replication more effectively.
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Emergence of SARS-CoV-2 variants of concern (VOCs), including the highly transmissible Omicron and Delta strains, has posed constant challenges to the current COVID-19 vaccines that principally target the viral spike protein (S). Here, we report a nucleoside-modified messenger RNA (mRNA) vaccine that expresses the more conserved viral nucleoprotein (mRNA-N) and show that mRNA-N vaccination alone can induce modest control of SARS-CoV-2. Critically, combining mRNA-N with the clinically proven S-expressing mRNA vaccine (mRNA-S+N) induced robust protection against both Delta and Omicron variants.

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A candidate multigenic SARS-CoV-2 vaccine based on an MVA vector expressing both viral N and S proteins (MVA-S + N) was immunogenic, and induced T-cell responses and binding antibodies to both antigens but in the absence of detectable neutralizing antibodies. Intranasal immunization with the vaccine diminished viral loads and lung inflammation in mice after SARS-CoV-2 challenge, which correlated with the T-cell response induced by the vaccine in the lung, indicating that T-cell immunity is also likely critical for protection against SARS-CoV-2 infection in addition to neutralizing antibodies.

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Zika virus (ZIKV) emerged from obscurity in 2013 to spread from Asia to the South Pacific and the Americas, where millions of people were infected, accompanied by severe disease including microcephaly following congenital infections. Phylogenetic studies have shown that ZIKV evolved in Africa and later spread to Asia, and that the Asian lineage is responsible for the recent epidemics in the South Pacific and Americas. However, the reasons for the sudden emergence of ZIKV remain enigmatic.

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In March of 2020, the World Health Organization declared a pandemic of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The pandemic led to a shortage of N95-grade filtering facepiece respirators (FFRs), especially surgical-grade N95 FFRs for protection of healthcare professionals against airborne transmission of SARS-CoV-2. We and others have previously reported promising decontamination methods that may be applied to the recycling and reuse of FFRs.

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In March of 2020, the World Health Organization declared a pandemic of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The pandemic led to a shortage of N95-grade filtering facepiece respirators (FFRs), especially for protection of healthcare professionals against airborne transmission of SARS-CoV-2. We and others have previously reported promising decontamination methods that may be applied to the recycling and reuse of FFRs.

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