A Rheological Study of the Association and Dynamics of MUC5AC Gels

• Main Authors: Rubinstein, Michael (Author), Wagner, Caroline E (Contributor), Turner, Bradley S. (Contributor), McKinley, Gareth H (Contributor), Ribbeck, Katharina (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Biological Engineering (Contributor), Massachusetts Institute of Technology. Department of Mechanical Engineering (Contributor)
• Format: Article
• Language: English
• Published: American Chemical Society (ACS), 2018-12-21T14:31:22Z.
• Subjects: Article
• Online Access: Get fulltext

The details of how a mucus hydrogel forms from its primary structural component, mucin polymers, remain incompletely resolved. To explore this, we use a combination of macrorheology and single-particle tracking to investigate the bulk and microscopic mechanical properties of reconstituted MUC5AC mucin gels. We find that analyses of thermal fluctuations on the length scale of the micrometer-sized particles are not predictive of the linear viscoelastic response of the mucin gels, and that taken together, the results from both techniques help to provide complementary insight into the structure of the network. In particular, we show that macroscopic stiffening of MUC5AC gels can be brought about in different ways by targeting specific associations within the network using environmental triggers such as modifications to the pH, surfactant, and salt concentration. Our work may be important for understanding how environmental factors, including pathogens and therapeutic agents, alter the mechanical properties of fully constituted mucus.
National Science Foundation (U.S.) (Grant PHY-1454673)
National Science Foundation (U.S.) (Grant DMR-1419807)
National Institutes of Health (U.S.) (Grant R01-EB017755)
National Institute of Environmental Health Sciences (Grant P30-ES002109)
Burroughs Wellcome Fund (Grant 1012566)