Toward the goal of establishing an engineered model of the vocal fold lamina propria (LP), mesenchymal stem cells (MSCs) are encapsulated in hyaluronic acid (HA)‐based hydrogels employing tetrazine ligation with strained alkenes. To mimic matrix stiffening during LP maturation, diffusion‐controlled interfacial bioorthogonal crosslinking is carried out on the soft cellular construct using HA modified with a ferocious dienophile,
- Award ID(s):
- 2037055
- NSF-PAR ID:
- 10346226
- Date Published:
- Journal Name:
- Frontiers in Medical Technology
- Volume:
- 4
- ISSN:
- 2673-3129
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract trans ‐cyclooctene (TCO). Cultures are maintained in MSC growth media for 14 days to afford a model of a newborn LP that is homogeneously soft (nLP), a homogeneously stiffened construct zero (sLP0) or 7 days (sLP7) post cell encapsulation, and a mature LP model (mLP) with a stiff top layer and a soft bottom layer. Installation of additional HA crosslinks restricts cell spreading. Compared to the nLP controls, sLP7 conditions upregulate the expression of fibrous matrix proteins (Col I, DCN , andFN EDA ), classic fibroblastic markers (TNC, FAP , andFSP1 ), and matrix remodeling enzymes (MMP2, TIMP1 , andHAS3 ). Day 7 stiffening also upregulates the catabolic activities, enhances ECM turnover, and promotesYAP expression. Overall, in situ delayed matrix stiffening promotes a fibroblast transition from MSCs and enhances YAP‐regulated mechanosensing. -
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3389/fmedt.2022.884314
