The stiffness of a crosslinked hyaluronan hydrogel affects its chondro‐induction activity on hADSCs

Abstract

Matrix stiffness plays an important role in stem cell differentiation. This study reports the synthesis of methacrylated hyaluronan (MeHA) with different degrees of methacrylation, ranging from 15 to 140% per disaccharide unit, which corresponds to a matrix stiffness ranging from 1.5 to 8 KPa. The swelling ratio was inversely proportional to the matrix stiffness, but the water content remained constant at >97% of the hydrogel mass. A fibril-like surface morphology and larger pore size were observed in lyophilized MeHA hydrogel with a lower stiffness. The matrix stiffness also affected the degradability of the MeHA hydrogel, where softer MeHA hydrogels (MeHA and MeHA ) were completely degraded within 6 days and a stiffer MeHA hydrogel (MeHA ) was able to retain ∼25% of its initial mass after 30 days. Subsequently, the crosslinked MeHA hydrogel was used as a scaffold to encapsulate human adipose-derived stem cells (hADSCs). The embedded cells remained viable and expressed ∼11-fold higher levels of aggrecan and 42-fold higher levels of collagen type II in MeHA compared with ADSCs cultured in HA-coated wells. In addition, cells grown in MeHA exhibited the highest rates of glycosaminoglycan and collagen type II synthesis of ∼5 ng/DNA and 0.4 ng/DNA, respectively. Immunofluorescence staining showed an increase of collagen type II synthesis in MeHA , MeHA and MeHA . This study showed that the matrix stiffness of a hydrogel can be modulated by the degree of methacrylation, thus affecting the efficacy of chondrogenesis in hADSCs. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 808-816, 2018.

Cartilage/bone interface fabricated under perfusion: Spatially organized commitment of adipose‐derived stem cells without medium supplementation

“…Importantly, after a preceding 2‐week static cultivation, the stiffness of the scaffold did not change during the following 2‐week dynamic cultivation of the piled construct in the bioreactor (Figure ). Therefore, the observed differentiation commitments of the ASCs under dynamic conditions must have resulted from the chemical gradient in combination with the applied shear stress – and not from changes in scaffold stiffness during the course of the experiment . Going along with these results, partial reduction in stemness markers, such as CD73 (90:10) and CD105 (70:30), was found, which might be explained by the on‐going differentiations, especially the two differentiations toward the chondro‐ and osteogenic lineages, respectively, under fluid flow, affected by primary cilia and cytoskeletal mechanotransduction …”

Reconstruction Strategies of the Ureter and Urinary Diversion Using Tissue Engineering Approaches

“…Changing the methacrylation percentage directly effects on the crosslinking density and stiffness of the hydrogel matrix. 83 HA has also been chemically functionalized for the attachment of reporter groups for drug delivery systems. Composite materials of HA with natural and synthetic polymers were developed into biomimetic scaffolds with ability of enhancing wound healing and angiogenesis.…”

“…Hydrogel Degree of methacrylation can modulate matrix stiffness of a hydrogel, thus affecting chondrogenesis 83 Han et al…”

“…The degree of methacrylation modulated matrix stiffness of the hydrogels, therefore affecting the ability of hADSC chondrogenesis. 83 PVA is one of the most studied polymers in biomedical application, because of its great biocompatibility in combination with a variety of appropriate biomechanical properties, swelling capacity, and crosslinking opportunities. Nanda et al 126 crosslinked the PVA-CS hydrogels with glutaraldehyde and used them as a scaffold in TE.…”

Elastin-Collagen Based Hydrogels as Model Scaffolds to Induce Three-Dimensional Adipocyte Culture from Adipose Derived Stem Cells

“…Tissue culture techniques to create three-dimensional adipose culture models come in a wide variety. Previous studies have used coated tissue culture polystyrene surfaces, synthetic polymer-based scaffolds, as well as hydrogels prepared using natural ECM-based and peptide-based polymers [ 6 , 7 , 9 , 10 , 11 , 12 , 13 , 14 ]. Cell culture in hydrogel scaffolds has been shown to more readily mimic the three-dimensional in vivo structure of an adipose tissue making it more advantageous to use than a two-dimensional monolayer culture [ 9 ].…”