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bioRxiv · 10.1101/2025.08.06.668852

Understanding Influenza A Virus particles detaching from reconstructed cell surfaces

Kolbe, T.·Gaspard, P.·Mognetti, B. M.
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Abstract

Influenza infection is a multistage process that involves the trafficking of viral particles across the cell membrane. Before endocytosis, virions target the membrane by binding hemagglutinin ligands to sialic acid residues on cell receptors. After budding, neuraminidase cleaves these residues, enabling virions to detach from the infected cell surface. ln this paper, we examine detachment dynamics through simulations and the-oretical analysis. We explain experimental findings showing that the time required for virions to detach can decrease as the single-trajectory average number of bridges increases-a counterintuitive result specific to neuraminidase activity. Furthermore, we demonstrate that the detachment time is not governed by a Poisson distribution but depends on multiple factors, including ligand-receptor reaction rates, virion size, and receptor diffusion constant. These results clarify how biochemical parameters regulate the residence time of virions at the cell surface. TOC Graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=111 SRC="FIGDIR/small/668852v1_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@2ae5d4org.highwire.dtl.DTLVardef@56e756org.highwire.dtl.DTLVardef@16de32dorg.highwire.dtl.DTLVardef@15dda8f_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Kolbe, T., Gaspard, P., Mognetti, B. M.. 2025-08-07. Understanding Influenza A Virus particles detaching from reconstructed cell surfaces. https://doi.org/10.1101/2025.08.06.668852

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