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Title: Matrix Degradability Contributes to the Development of Salivary Gland Progenitor Cells with Secretory Functions
Synthetic matrices that are cytocompatible, cell adhesive and cell responsive are needed for the engineering of implantable, secretory salivary gland constructs to treat radiation induced xerostomia or dry mouth. Here, taking advantage of the bioorthogonality of the Michael-type addition reaction, hydrogels with comparable stiffness but varying degrees of degradability (100% degradable: 100DEG; 50% degradable: 50DEG; and non-degradable: 0DEG) by cell-secreted matrix metalloproteases (MMPs) were synthesized using thiolated HA (HA-SH), maleimide (MI)-conjugated integrin-binding peptide (RGD-MI) and MI-functionalized peptide crosslinkers that are protease degradable (GIW-bisMI) or non-degradable (GIQ-bisMI). Organized multicellular structures developed readily in all hydrogels from dispersed primary human salivary gland stem/progenitor cells (hS/PCs). As the matrix became progressively degradable, cells proliferated more readily and the multicellular structures became larger, less spherical, and more lobular. Immunocytochemical analysis showed positive staining for stem/progenitor cell markers CD44 and keratin 5 (K5) in all three types of cultures, and positive staining for the acinar marker α-amylase under 50DEG and 100DEG conditions. Quantitatively at the mRNA level, the expression levels of key stem/progenitor markers KIT, KRT5, and ETV4/5 were significantly increased in the degradable gels as compared to the non-degradable counterparts. Western blot analyses revealed that imparting matrix degradation led to >3.8-fold increase in KIT expression by day 15. The MMP-degradable hydrogels also promoted the development of a secretary phenotype, as evidenced by the upregulation of acinar markers α-amylase (AMY), aquaporin-5 (AQP5), and sodium-potassium-chloride cotransporter 1 (SLC12A2). Collectively, we show that cell-mediated matrix remodeling is necessary for the development of regenerative pro-acinar progenitor cells from hS/PCs.  more » « less
Award ID(s):
2243648
NSF-PAR ID:
10497610
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
ACS
Date Published:
Journal Name:
ACS Applied Materials & Interfaces
Volume:
15
Issue:
27
ISSN:
1944-8244
Page Range / eLocation ID:
32148 to 32161
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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