Release of infectious virus and cytokines in nasopharyngeal swabs from individuals infected with non-B.1.1.7 or B.1.1.7 SARS-CoV-2 variants

作者：Blandine Monel, Delphine Planas, Ludivine Grzelak, Nikaïa Smith, Nicolas Robillard, Isabelle Staropoli, Pedro Gonçalves, Françoise Porrot, Florence Guivel‐Benhassine, Nathalie Demory Guinet, Julien Rodary, Julien Puech, Victor Euzen, Laurent Bélec, Galdric Orvoën, Léa Nunes, Véronique Moulin, Jacques Fourgeaud, Maxime Wack, Sandrine Imbeaud, Pascal Campagne, Darragh Duffy, James P. Di Santo, Timothée Bruel, Hélène Péré, David Veyer, Olivier Schwartz · 发表于：medRxiv · 年份：2021 · DOI：10.1101/2021.05.20.21257393 · 被引用次数：4 · 研究领域：SARS-CoV-2 detection and testing、SARS-CoV-2 and COVID-19 Research、Respiratory viral infections research

Abstract The mechanisms that allowed for the SARS-CoV-2 B.1.1.7 variant to rapidly outcompete pre-existing variants in many countries remain poorly characterized. Here, we analyzed viral release, anti-SARS-CoV-2 antibodies and cytokine production in a retrospective series of 427 RT–qPCR+ nasopharyngeal swabs collected in COVID-19 patients harbouring either non-B.1.1.7 or B.1.17 variants. We utilized a novel rapid assay, based on S-Fuse-T reporter cells, to quantify infectious SARS-CoV-2. With both non-B.1.1.7 and B.1.1.7 variants, viral titers were highly variable, ranging from 0 to >10 6 infectious units, and correlated with viral RNA levels. Lateral flow antigenic rapid diagnostic tests (RDTs) were positive in 96% of the samples harbouring infectious virus. About 67 % of individuals carried detectable infectious virus within the first two days after onset of symptoms. This proportion decreased overtime, and viable virus was detected up to 14 days. Samples containing anti-SARS-CoV-2 IgG or IgA did not generally harbour infectious virus. The proportion of individuals displaying viable virus or being RDT-positive was not higher with B.1.1.7 than with non-B.1.1.7 variants. Ct values were slightly but not significantly lower with B.1.1.7. The variant was characterized by a fast decrease of infectivity overtime and a marked release of 17 cytokines (including IFN-β, IP-10, IL-10 and TRAIL). Our results highlight differences between non-B.1.1.7 and B.1.1.7 variants. B.1.1.7 is a...