Replicating cilia movement and mucus interactions through detailed modeling
Replicating cilia movement and mucus interactions through detailed modeling lead image
The first line of defense our bodies have against respiratory invaders is our mucus. A layer of mucus lines our airways to trap invasive particles, and this layer is propelled along by the collective movement of cilia. An accurate model of this movement is key to better understanding this first-line defense in healthy individuals and the effects of respiratory illnesses.
Laborie et al. built a computational framework to study the movement of cilia and the resulting flow of mucus. Their framework allows for detailed study in an environment where experimental data is hard to obtain.
“It is difficult to monitor how cilia move in a real environment,” said author Fabio Sterpone. “There is also a problem of spatial resolution.”
The team modeled cilia and their movement in three dimensions, both during a ‘power stroke’ that propels the mucus forward and during a ‘recovery stroke’ where the cilia return to their starting locations. They used their model to reproduce the metachronal wave, a known behavior of cilia involving coordinated, progressive cilia pulses with a characteristic frequency and wavelength. They embedded these cilia inside a two-layer fluid tuned to represent the viscous mucus and the water-like periciliary fluid layer that sits beneath it.
After verifying that their framework replicates realistic conditions, the team plans to modify those conditions to explore the impact of disease.
“We are testing the standard conditions of the epithelial cell environment compared to epithelial cells that suffer from some handicap such as immotility of the cilia or even deciliation,” said Sterpone. “These happen in some diseases like primary ciliary dyskinesia or infections.”
Source: “An operative framework to model mucus clearance in silico by coupling cilia motion with the liquid environment,” by Emeline Laborie, Simone Melchionna, and Fabio Sterpone, Journal of Chemical Physics (2023). The article can be accessed at https://doi.org/10.1063/5.0135216 .
