The New England Journal of Medicine published a great medical image this week from our nasal friend, or at least a runny nasal friend.
This is the typical pattern of healthy mucus, a chemical composite of water, electrolytes, and glycoproteins (sugars attached to proteins)
“When there is a balance of these nonaqueous components in healthy mucus, the evaporation of water can lead to crystallization of the electrolytes, and fern formation occurs.”
The mucus found in our noses and respiratory passages form the first physical defense against intruders, be they biologic like COVID-19 or particulate, like soot. The mucus traps these particles and cilia, microscopic hairlike parts of the outer cell wall, push the mucus up and out of our respiratory tract into our mouth and nose, where they may be disposed of by a swallow or a timely tissue.
Source: NEJM Ferning in Nasal Mucus DOI: 10.1056/NEJMicm2034441