Question: how is mucus made? ~ Sofia and Sadie :)

Erin Pallott answered on 9 May 2024:

Mucus is firstly a gel made up of strands of long proteins that interact with water to form a gel. There are also more proteins, antibodies, ions and salts mixed into this gel. This mucus covers many of your surfaces including your mouth, throat, eyes, nose, lungs, stomach, intestines and cervix. The mucus at each of these sites is slightly different, and produced by slightly different mucous cells.

I work on intestinal mucus, which is produced by goblet cells in the epithelium (the lumen-facing lining). It produces the mucus protein “MUC2” which is a long protein densely covered with sugars. This gets secreted from the goblet cells and begins to form networks with the other MUC2 molecules and turns into a gel with water. This layer covers the entire epithelium and gradually sheds off as its degraded by the microbiota, contents moving through and our own protein degrading enzymes.

It costs a lot of energy to make all the mucus across our body, but our barrier sites would be very at risk to infection without it!