How cells wrap around coronavirus-like particles using extracellular filamentous protein structures

Nanoparticles, like viruses, infiltrate cells via endocytosis. During this process, the cell surface wraps around the nanoparticle to effectively eat it. Prior focus has been on how nanoparticle size and shape impact endocytosis. However, inspired by extracellular vimentin's impact on viral and bacterial uptake and the structure of coronaviruses, we construct a computational model in which both the cell-like and virus-like constructs contain protruding filamentous protein structures. By studying the impact of these structures on viral wrapping, we found that cells with an optimal density of filamentous extracellular components (ECCs) were more susceptible to infection. They displayed faster virus uptake and efficient use of cell surface area. These cells folded their surface around the virus in a faster, more efficient wrapping process as compared to crumple-like wrapping. We also found that cell surface rigidity aids fold formation; however, altering mechanical factors, such as filamentous ECC or virus spike stiffness, can induce crumpling. Our study identifies new evolutionary pressures for viruses given the cellular microenvironment that includes filamentous ECCs.