Efficient Surface Immobilization of Chemically Modified Hyaluronans for Enhanced Bioactivity and Survival of In Vitro-Cultured Embryonic Salivary Gland Mesenchymal Cells.

Sang-Woo Lee,Xin Cong,Junchul Kim,Ji Hyun Ryu,Kyungpyo Park,Guang-Yan Yu

doi:10.3390/polym13081216

Abstract

Embryonic salivary gland mesenchyme (eSGM) secretes various growth factors (bioactives) that support the proper growth and differentiation of salivary gland epithelium. Therefore, eSGM cells can be used as feeder cells for in vitro-cultured artificial salivary gland if their survival and bioactivity are properly maintained. As eSGM is encapsulated in a hyaluronan (HA)-rich developmental milieu, we hypothesized that mimicking this environment in vitro via surface immobilization of HA might enhance survival and bioactivity of eSGM. In this study, various HA derivatives, conjugated with catechol (HA–CA), thiol (HA–SH), or amine (HA–EDA) moieties, respectively, were screened for their efficacy of culturing eSGM-derived feeder cells in vitro. Among these HA derivatives, HA–CA showed the highest surface coating efficiency and growth enhancement effect on the embryonic submandibular gland. In addition, the HA–CA coating enhanced the production of growth factors EGF and FGF7, but not FGF10. These effects were maintained when eSGM cells isolated from the embryonic salivary gland were re-seeded to develop the feeder layer cells. CD44s (a major HA receptor) in eSGM cells were clustered at the cell membrane, and enhanced EGF expression was detected only in CD44 cluster-positive cells, suggesting that membrane clustering of CD44 is the key mechanism for the increased expression of EGF.

Highlights

Introduction iationsHyaluronan (hyaluronic acid (HA)) is a natural biopolymer abundantly found in the extracellular matrix (ECM) of various human tissues
HA–EDA has not yet been used for salivary gland tissue engineering, it was selected as a candidate in the current study because the amine moiety can interact with various biological molecules [26,27]
We hypothesized that the HA–CA coating-induced effects are mediated by CD44, abundantly expressed in mesenchyme from the early developmental stages (Figure S2)

Summary

Introduction

Hyaluronan (hyaluronic acid (HA)) is a natural biopolymer abundantly found in the extracellular matrix (ECM) of various human tissues. Due to its diverse bioactivities and excellent biocompatibility, HA has been widely studied for biomedical applications, including tissue engineering, drug delivery, regenerative medicine, and bio-lubrication [1]. In the various biomedical fields, chemically modified HAs have been used to enhance the bioactivity of adipose-derived stem cells [7], neural stem cells [6], endothelial cells [8], and salivary gland stem/progenitor cells [9]. Such biological effects of HA or HA derivatives

Methods

Results

Conclusion