2) The researchers performed deep mutational scanning of residues 808-855 of the SARS-CoV-2 spike protein, which spans the S2' cleavage site, fusion peptide and adjacent regions
3) They identified mutations at residue 813 upstream of the S2' cleavage site that reduced sensitivity to TMPRSS2-mediated cleavage and cell surface entry. Mutations S813V and S813K decreased virus virulence in mice.
4) The fusion peptide (residues 816-834) was found to have very low mutational tolerance, indicating its functional importance for membrane fusion.
5) An F823Y mutation in the fusion peptide conferred resistance to two broadly neutralizing antibodies (COV44-62 and COV44-79) that target this region. Structural modeling suggested the mutation disrupts antibody binding.
6) The findings provide insights into SARS-CoV-2 pathogenicity and cell entry pathway usage. They also highlight a potential challenge for developing pan-coronavirus vaccines targeting the fusion peptide region.
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2) In this study, researchers examined the heterogeneity of long-lived antibody-producing plasma cells residing in human bone marrow. Using single-cell RNA sequencing of over 38,000 bone marrow plasma cells, 10 distinct "clans" were identified ... nature.com/articles/s4146โฆ
3) ... that differed in gene expression patterns reflecting the signals plasma cells encountered during activation either in follicular reactions involving IL-21 or extrafollicular reactions without IL-21. Analysis of immune cells exiting vaccination responses over time ...
2) SARS-CoV-2 infection increases risk of neurodegenerative diseases like Alzheimer's and dementia by triggering neuroinflammation and vascular damage, as evidenced by studies linking COVID to later diagnoses. thelancet.com/journals/laneuโฆ
3) Mechanisms include viral proteins triggering tau aggregation and amyloid formation, while infection allows virus/proteins to persist and cause long-term inflammation.
2) This study estimated hourly airborne SARS-CoV-2 transmission risk in daycare rooms by calculating inhaled viral doses from occupancy, activities, and aerosol emission/transport models. Risks significantly varied by room and time ... cell.com/heliyon/fullteโฆ
3) ... with changing rooms and lunchrooms having the highest risks. Sensitivity analysis found viral shedding rates and infectious doses to be key uncertainties. While absolute risks are uncertain, the method effectively identified higher-risk spaces and ...
โถ๏ธ EGYPT, Seroprevalence H5N1 in poultry workers : 2.1% (2015), equivalent of 20.000 workers ?
โถ๏ธ WHO, 356 human cases of H5N1 reported in Egypt (9 March 2006 - 30 September 2016)
โถ๏ธ 98% ๐ก๐ข๐ง ๐๐๐ง๐๐๐ง๐๐ ?
2) The study in Egypt found that the seroprevalence of avian influenza A(H5N1) antibodies was higher among poultry-exposed individuals. Chronic lung disease was a significant risk factor for infection. A(H9N2) infection was also detected ...
3) ...after circulating in poultry. The study suggests more humans are infected with avian influenza than reported. academic.oup.com/jid/article/21โฆ
2) A brief summary :
In this article they said that in the event of a human-transmitted avian influenza pandemic before effective vaccines or antiviral drugs are available, the outbreak could be significantly slowed through passive immunization with milk and serum ...
3) ... from cows intranasally inoculated with heat-sterilized avian influenza patient samples.
The proposed approach involves having people consume raw milk from herds of pathogen-free cows given intranasal influenza sputum samples, supplemented by ...
2) COVID-19 (caused by SARS-CoV-2 virus) can cause neurological symptoms like memory loss, cognitive issues, and sensory disruption. These symptoms are sometimes referred to as neuro-COVID.
3) Researchers believe viral protein fragments from SARS-CoV-2 may be aggregating into amyloid nanofibrils in the brain, contributing to neuro-COVID symptoms. Two fragments from ORF6 and ORF10 proteins were previously found to self-assemble into neurotoxic amyloids.