Publisher Correction: SARS-CoV-2 Omicron is an immune escape variant with an altered cell entry pathway

Vaccine-induced correlate of protection against fatal COVID-19 in older and frail adults during waves of neutralization-resistant variants of concern: an observational study

“…This may be attributable to the described significant escape from neutralizing antibodies by Omicron. 16 , 28 It has previously been shown that vaccine-induced neutralizing antibodies provided a correlate of protection against infection with the ancestral strain or relatively homologous VOCs. 29 , 30 Our results complement these data and demonstrates that S-binding IgG antibody levels provide a correlate of protection against fatality related to infections with VOCs.…”

TMPRSS2 activation of Omicron lineage Spike glycoprotein is regulated by Collectrin-like domain of ACE2

“…Hek 293T and VeroE6 have been extensively used in virological assays, as they lack key innate immune mechanisms and as such represent pragmatic cell substrates for assay platform development and also viral propagation 19–22 . At the juncture of the Delta to Omicron BA.1 shift in the pandemic, both ourselves and others struggled to isolate and maintain primary viral isolates in a manner similar to what we had observed prior to BA.1, as in many cases the ACE2-TMPRSS2 pathway that previously was functional for early variants, appeared no longer functional for Omicron lineages 17,19,23–25 . To increase the efficiency of primary isolations from nasopharyngeal swabs, we screened existing cell lines across primary isolates encompassing the major variants that have appeared over the last three years globally (Fig.…”

“…The HEK293T and VeroE6 cell lines have been extensively used in virological assays as starting substrates, as they lack key host restriction mechanisms and as such are suited for assay platform development and viral propagation 16–19 . Whilst the latter approach was used successfully pre-Omicron, evidence rapidly emerged demonstrating that Omicron lineages no longer effectively utilized the ACE2-TMPRSS2 pathway in various cell lines and primary cell settings 14,16,24–26 . To increase the efficiency of primary isolations from nasopharyngeal swabs, we screened existing cell lines for susceptibility to infection across viral variants representative of the major variants globally from the last three years (Fig.…”

“…The arrival of the initial BA.1 and BA.2 Omicron lineages shortly after Delta was a seismic shift at two levels. Firstly, the ability of Omicron lineages to efficiently evade neutralising antibodies, and secondly, a shift in tropism away from the lower respiratory tract 4–6,17–19 . This combination has driven waves globally that surpassed that prior to Delta.…”

Vaccine-induced correlate of protection against fatal COVID-19 in the old and frail during waves of neutralization resistant variants of concern

“…We found no pattern supporting that higher levels of circulating S-binding IgG protected against SARS-CoV-2 infection. This may be attributable to the described significant escape from neutralizing antibodies by Omicron 21,22 . It has previously been shown that vaccine-induced neutralizing antibodies provided a correlate of protection against infection with the ancestral strain or relatively homologous VoCs 23,24 .…”