A5063853016- SARS-CoV-2 detection and testing
- SARS-CoV-2 and COVID-19 Research
- COVID-19 Clinical Research Studies
- Biosensors and Analytical Detection
- Advanced biosensing and bioanalysis techniques
- Advanced Biosensing Techniques and Applications
- Monoclonal and Polyclonal Antibodies Research
- Respiratory viral infections research
- Viral Infections and Outbreaks Research
- Glycosylation and Glycoproteins Research
- Long-Term Effects of COVID-19
- Bacillus and Francisella bacterial research
University of Geneva
2017-2024
University Hospital of Geneva
2024
Emerging SARS-CoV-2 variants raise questions about escape from previous immunity. As the population immunity to has become more complex due prior infections with different variants, vaccinations or combination of both, understanding antigenic relationship between is needed. Here, we have assessed neutralizing capacity 120 blood specimens convalescent individuals infected ancestral SARS-CoV-2, Alpha, Beta, Gamma Delta, double vaccinated and patients after breakthrough Delta Omicron-BA.1....
Abstract Background Viral load (VL) is one determinant of secondary transmission SARS-CoV-2. Emergence variants concerns (VOC) Alpha and Delta was ascribed, at least partly, to higher VL. Furthermore, with parts the population vaccinated, knowledge on VL in vaccine-breakthrough infections crucial. As RNA only a weak proxy for infectiousness, studies infectious virus presence by cell culture isolation are importance. Methods We assessed nasopharyngeal swabs COVID-19 patients quantitative...
Abstract Emerging variants of concern (VOCs) are driving the COVID-19 pandemic 1,2 . Experimental assessments replication and transmission major VOCs progenitors needed to understand mechanisms 3 Here we show that spike protein (S) from Alpha (also known as B.1.1.7) Beta (B.1.351) had a greater affinity towards human angiotensin-converting enzyme 2 (ACE2) receptor than progenitor variant S(D614G) in vitro. Progenitor virus expressing (wt-S 614G ) showed similar kinetics nasal airway...
Sensitivity for detecting Omicron-BA.1 shows high heterogenicity between Ag-RDTs, necessitating a careful consideration when using these tests to guide infection prevention measures. Analytical and retrospective testing is proxy timely solution generate rapid performance data, but it not replacement clinical evaluations, which are urgently needed. Biological technical reasons detection failure by some Ag-RDTs need be further investigated.
Abstract Background The emergence of each novel SARS-CoV-2 variants concern (VOCs) requires investigation its potential impact on the performance diagnostic tests in use, including Antigen-detecting rapid (Ag-RDT). Although anecdotal reports have been circulating that newly emerged Omicron variant is principle detectable by Ag-RDTs, few data sensitivity are available. Methods We performed 1) analytical testing with cultured virus eight Ag-RDTs and 2) retrospective duplicates clinical samples...
Mucosal antibodies play a key role in the protection against SARS-CoV-2 infection upper respiratory tract, and potentially limiting virus replication therefore onward transmission. While systemic immunity to is well understood, we have limited understanding about present on nasal mucosal surfaces.
<title>Abstract</title> Pregnancy constitutes an at-risk factor for severe COVID-19. Several clinical studies have previously suggested increased risks of adverse obstetrical outcomes and placental pathological changes in pregnant women infected with SARS-CoV-2. In this study, our goal was to assess the susceptibility trophoblast SARS-CoV-2 infection at early stage pregnancy its impact on cell fusion <italic>in vitro</italic>. We showed that first trimester cytotrophoblast (CTB)...
In the 5th year after emergence of SARS-CoV-2, Omicron lineages continue to evolve and cause infections. Here, we used eight authentic SARS-CoV-2 isolates assess their capacity escape immunity different exposure histories replicative in polarized human airway epithelial cells (HAE) derived from nasal bronchial epithelium. Using live-virus neutralization assays 108 sera or plasma immunological backgrounds, progressive immune was observed B.1 (ancestral virus) EG.5.1, but no significant...
Emerging SARS-CoV-2 variants of concern/interest (VOC/VOI) raise questions about effectiveness neutralizing antibodies derived from infection or vaccination. As the population immunity to has become more complex due prior and/or vaccination, understanding antigenic relationship between is needed. Here, we have assessed in total 104 blood specimens convalescent individuals after with early-pandemic (pre-VOC) Alpha, Beta, Gamma Delta, post-vaccination double-dose mRNA-vaccination and break...
Abstract Viral load (VL) is one determinant of secondary transmission SARS-CoV-2. Emergence variants concerns (VOC) Alpha and Delta was ascribed, at least partly, to higher VL. Furthermore, with parts the population vaccinated, knowledge on VL in vaccine-breakthrough infections crucial. As RNA only a weak proxy for infectiousness, studies infectious virus presence by cell culture isolation are importance. We assessed nasopharyngeal swabs COVID-19 patients quantitative viral titres (IVT)...
Abstract Emerging variants of concern (VOCs) drive the SARS-CoV-2 pandemic. We assessed VOC B.1.1.7, now prevalent in several countries, and B.1.351, representing greatest threat to populations with immunity early progenitors. B.1.1.7 showed a clear fitness advantage over progenitor variant (wt-S 614G ) ferrets two mouse models, where substitutions spike glycoprotein were major drivers for advantage. In “superspreader” hamster model, wt-S had comparable fitness, whereas B.1.351 was...
Abstract Global concerns arose as the emerged and rapidly spreading SARS-CoV-2 Delta variant. To date, few data on routine diagnostic performance for are available. Here, we investigate analytical of eleven commercially available antigen-detecting rapid tests (Ag-RDTs) VOC in comparison with current earlier VOCs (Alpha, Beta Gamma) early pandemic variant using cultured SARS-CoV-2. Comparable sensitivity was observed majority Ag-RDTs.
Antibody phage display technology has supported the emergence of numerous therapeutic antibodies. The development bispecific antibodies, a promising new frontier in antibody therapy, could be facilitated by approaches that enable pairs antibodies to co-selected based on co-engagement their respective targets. We describe such an approach, making use two complementary leucine zipper domains heterodimerize with high affinity. Phagemids encoding first fragment (scFv) fused coat protein via are...
Abstract Several SARS-CoV-2 variants of concern/interest (VOC/VOI) emerged recently, with VOCs outcompeting earlier lineages on a global scale. To date, few data routine diagnostic performance for VOC/VOIs are available. Here, we investigate the analytical nine commercially available antigen-detecting rapid tests (Ag-RDTs) VOC B.1.1.7, B.1.351, P.1 and VOI P.2 cultured SARS-CoV-2. Comparable or higher sensitivity was observed VOC/VOI compared to non-VOC/VOI early-pandemic virus all Ag-RDTs.
AH971 and AV865 antibodies detect the nucleocapsid proteins of severe acute respiratory SARS coronavirus-2 (SARS-CoV-2) in a focus forming assay.
Abstract Mucosal antibodies play a key role in the protection against SARS-CoV-2 infection upper respiratory tract, and potentially limiting virus replication therefore onward transmission. While systemic immunity to is well understood, little known about present on nasal mucosal surfaces. In this study, we evaluated response infection, vaccination, or combination of both. Paired fluid serum samples were collected from 136 individuals, which include convalescent, vaccinated, breakthrough...
SARS-CoV-2′s genetic plasticity has led to several variants of concern (VOCs). Here we studied replicative capacity for seven SARS-CoV-2 isolates (B.1, Alpha, Beta, Gamma, Delta, Zeta, and Omicron BA.1) in primary reconstituted airway epithelia (HAE) lung-derived cell lines. Furthermore, investigate the host range Delta compared ancestral SARS-CoV-2, assessed replication 17 lines from 11 non-primate mammalian species, including bats, rodents, insectivores carnivores. Only Omicron's phenotype...
Abstract SARS-CoV-2’s genetic plasticity has led to several variants of concern (VOCs). Here we studied replicative capacity for seven SARS-CoV-2 isolates (B.1, Alpha, Beta, Gamma, Delta, Zeta, and Omicron BA.1) in primary reconstituted airway epithelia (HAE) lung-derived cell lines. Furthermore, investigate the host range Delta compared ancestral SARS-CoV-2, assessed replication 17 lines from 11 non-primate mammalian species, including bats, rodents, insectivores carnivores. Only Omicron’s...