Publications by authors named "Dami A Collier"
Article Synopsis
- Elderly individuals (70 years and older) show weaker antibody responses to a COVID-19 booster compared to younger people after receiving an initial two-dose vaccine series with AZD1222 and a third mRNA booster.
- The elderly have a specific type of B cells (anomalous spike-specific B cells) that may impair their ability to neutralize the virus effectively after the booster.
- Interestingly, when elderly individuals receive three doses of mRNA vaccines, their antibody responses are comparable to those younger than 70, suggesting that different vaccine technologies influence immune memory formation.
National lockdowns have led to significant interruption to children's education globally. In the Autumn term in 2020, school absence in England and Wales was almost five times higher than the same period in 2019. Transmission of SARS-CoV-2 in schools and ongoing interruption to education remains a concern.
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- The B.1.617.2 (Delta) variant of SARS-CoV-2 was first detected in Maharashtra, India, late 2020, and quickly outcompeted earlier variants like B.1.617.1 (Kappa) and B.1.1.7 (Alpha).
- This variant shows significantly reduced sensitivity to neutralizing antibodies from both recovered individuals and vaccine recipients, with lower protection observed in those vaccinated with the ChAdOx1 serum compared to BNT162b2.
- Due to its higher replication efficiency and ability to evade the immune response, B.1.617.2's dominance highlights the need for ongoing infection control measures even after vaccination.
Although two-dose mRNA vaccination provides excellent protection against SARS-CoV-2, there is little information about vaccine efficacy against variants of concern (VOC) in individuals above eighty years of age. Here we analysed immune responses following vaccination with the BNT162b2 mRNA vaccine in elderly participants and younger healthcare workers. Serum neutralization and levels of binding IgG or IgA after the first vaccine dose were lower in older individuals, with a marked drop in participants over eighty years old.
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- The study focuses on the ΔH69/V70 deletion in the SARS-CoV-2 spike protein, found in various lineages alongside mutations like N439K and Y453F that enhance the virus's ability to bind to the ACE2 receptor and evade antibodies.
- While ΔH69/V70 does not directly help the virus escape antibodies, it increases overall infectivity by improving how the spike protein integrates into virus particles.
- The research underscores the importance of monitoring such deletions, as they may help the virus maintain its infectivity despite other mutations that could weaken it.
Transmission of SARS-CoV-2 is uncontrolled in many parts of the world; control is compounded in some areas by the higher transmission potential of the B.1.1.
View Article and Find Full Text PDFSevere Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) transmission is uncontrolled in many parts of the world, compounded in some areas by higher transmission potential of the B1.1.7 variant now seen in 50 countries.
View Article and Find Full Text PDFThe spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for virus infection through the engagement of the human ACE2 protein and is a major antibody target. Here we show that chronic infection with SARS-CoV-2 leads to viral evolution and reduced sensitivity to neutralizing antibodies in an immunosuppressed individual treated with convalescent plasma, by generating whole-genome ultra-deep sequences for 23 time points that span 101 days and using in vitro techniques to characterize the mutations revealed by sequencing. There was little change in the overall structure of the viral population after two courses of remdesivir during the first 57 days.
View Article and Find Full Text PDFThere is an urgent need for rapid SARS-CoV-2 testing in hospitals to limit nosocomial spread. We report an evaluation of point of care (POC) nucleic acid amplification testing (NAAT) in 149 participants with parallel combined nasal and throat swabbing for POC versus standard lab RT-PCR testing. Median time to result is 2.
View Article and Find Full Text PDFNeurocognitive impairment remains an important HIV-associated comorbidity despite combination antiretroviral therapy (ART). Since the advent of ART, the spectrum of HIV-associated neurocognitive disorder (HAND) has shifted from the most severe form to milder forms. Independent replication of HIV in the central nervous system despite ART, so-called cerebrospinal fluid (CSF) escape is now recognised in the context of individuals with a reconstituted immune system.
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- HIV-1 can independently replicate in the central nervous system, leading to conditions known as cerebrospinal fluid (CSF) discordance and escape, which may be linked to neurological symptoms in patients.
- A study involving 146 HIV-infected adults found that 14.7% of cases showed CSF discordance, with some patients experiencing CSF escape despite suppressed plasma viral loads.
- Diffuse white matter signal abnormalities on brain scans were significantly associated with both CSF discordance and escape, indicating the need for further investigation in patients presenting with neurological issues.
The gag gene is highly polymorphic across HIV-1 subtypes and contributes to susceptibility to protease inhibitors (PI), a critical class of antiretrovirals that will be used in up to 2 million individuals as second-line therapy in sub Saharan Africa by 2020. Given subtype C represents around half of all HIV-1 infections globally, we examined PI susceptibility in subtype C viruses from treatment-naïve individuals. PI susceptibility was measured in a single round infection assay of full-length, replication competent MJ4/gag chimeric viruses, encoding the gag gene and 142 nucleotides of pro derived from viruses in 20 patients in the Zambia-Emory HIV Research Project acute infection cohort.
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