2) The SARS-CoV-2 Omicron variant JN.1 has evolved into several sublineages containing recurrent spike protein mutations R346T, F456L, and T572I. Some sublineages like KP.2 containing combinations of these mutations have shown growth advantages.
3) This study characterized these mutations individually and in combination using pseudoviruses with the mutated spikes.
Serum neutralization assays found F456L significantly reduced antibody neutralization, while R346T and T572I had little effect.
4) Combinations including F456L were most resistant to antibodies.
F456L impaired neutralization of monoclonal antibodies targeting the RBD class 1 region. T572I modestly reduced SD1-directed antibody neutralization.
5) R346T increased binding affinity to the ACE2 receptor by 1.5-fold and modestly enhanced pseudovirus infectivity. F456L and T572I did not affect receptor binding.
KP.2, which contains R346T, F456L and V1104L, showed similar resistance as JN.1 with R346T and F456L ...
6) ...suggesting V1104L does not impact antibody evasion.
The study characterized how these recurrent mutations confer advantages like antibody evasion and receptor binding that help explain the expansion of lineages containing them, informing vaccine booster design.
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2) This study, that we posted in 2023, was finally published in 2024.
Researchers studied 43 individuals who had cleared SARS-CoV-2 infection (recovered, R group) and individuals experiencing persistent symptoms at least 8 months after infection (long COVID, LC group).
3) Multi-omics analyses including CyTOF, flow cytometry, RNA-seq, single-cell RNA-seq and serology were performed on blood samples from these individuals.ย
The LC group showed systemic inflammation and immune dysregulation. T cell subset distribution was perturbed ...
2) Researchers generated double-transgenic mice expressing both human angiotensin-converting enzyme 2 (hACE2) and human transmembrane protease serine 2 (hTMPRSS2) to increase their susceptibility to SARS-CoV-2 infection.
3) In vitro and in vivo experiments showed that co-expression of hACE2 and hTMPRSS2 enhanced SARS-CoV-2 infectivity and entry.
The double-transgenic mice exhibited significant weight loss, clinical symptoms, lung injury, inflammation and lethality when infected with SARS-CoV-2.
SARS-CoV-2 vgRNA accumulates in infected cells into CLUSTERS that grow, from small clusters at 6 hours to larger clusters by 24 hours
2) It is a complete new way to see viruses in action !!!
Using super-resolution microscopy, researchers revealed details of SARS-CoV-2 replication in host cells. They labeled viral RNA and proteins with fluorescent probes and suppressed fluorescence ...news.stanford.edu/stories/2024/0โฆ
3) ...to image individual molecules blinking on and off, achieving 10nm resolution. Images showed RNA accumulating over 6-24 hours into growing clusters around the nucleus that contain replication machinery.
2) The study analyzes long COVID services offered by top US hospitals. 86% had clinics/programs, usually called clinics. Common initial services were meeting specialists like neurologists, psychologists and pulmonologists.
Long COVID centers/programs among the top US hospitals
3) No single department housed most clinics. 65% didn't detail services provided. Standards for care are needed given diverse symptoms. 61% of hospitals didn't specify minimum symptom duration.
2) Wastewater surveillance using quantitative PCR (qPCR) is an effective tool for monitoring SARS-CoV-2 levels in communities. However, qPCR results can be impacted by mutations in the virus genome regions targeted by the PCR primers and probes.
3) In Japan in mid-2022, estimates of SARS-CoV-2 levels in wastewater started to diverge between assays targeting the N1 and N2 genome regions. This coincided with the emergence of omicron variants containing mutations in the N1 probe region.