Publications by authors named "B Segelke"

The polymorphic membrane proteins (Pmps) are a family of autotransporters that play an important role in infection, adhesion and immunity in Chlamydia trachomatis. Here we show that the characteristic GGA(I,L,V) and FxxN tetrapeptide repeats fit into a larger repeat sequence, which correspond to the coils of a large beta-helical domain in high quality structure predictions. Analysis of the protein using structure prediction algorithms provided novel insight to the chlamydial Pmp family of proteins.

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The COVID-19 pandemic underscored the promise of monoclonal antibody-based prophylactic and therapeutic drugs and revealed how quickly viral escape can curtail effective options. When the SARS-CoV-2 Omicron variant emerged in 2021, many antibody drug products lost potency, including Evusheld and its constituent, cilgavimab. Cilgavimab, like its progenitor COV2-2130, is a class 3 antibody that is compatible with other antibodies in combination and is challenging to replace with existing approaches.

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Article Synopsis
  • Viral populations in natural infections can vary widely genetically, affecting their ability to evade immune responses, yet most potency tests use a uniform viral strain, which may not reflect real-world scenarios.
  • Researchers explored whether genetically diverse recombinant SARS-CoV-2 spike virus stocks could better represent circulating viruses by conducting passage experiments under selective pressures.
  • Their findings showed that viral stocks passaged with selection pressure rapidly acquired mutations that helped them escape neutralization by monoclonal antibodies, suggesting that using genetically diverse stocks provides more accurate insights in antibody assessment assays.
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Genetic analysis of intra-host viral populations provides unique insight into pre-emergent mutations that may contribute to the genotype of future variants. Clinical samples positive for SARS-CoV-2 collected in California during the first months of the pandemic were sequenced to define the dynamics of mutation emergence as the virus became established in the state. Deep sequencing of 90 nasopharyngeal samples showed that many mutations associated with the establishment of SARS-CoV-2 globally were present at varying frequencies in a majority of the samples, even those collected as the virus was first detected in the US.

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The COVID-19 pandemic underscored the promise of monoclonal antibody-based prophylactic and therapeutic drugs, but also revealed how quickly viral escape can curtail effective options. With the emergence of the SARS-CoV-2 Omicron variant in late 2021, many clinically used antibody drug products lost potency, including Evusheld and its constituent, cilgavimab. Cilgavimab, like its progenitor COV2-2130, is a class 3 antibody that is compatible with other antibodies in combination and is challenging to replace with existing approaches.

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