Multilayered Films Produced by Layer-by-Layer Assembly of Chitosan and Alginate as a Potential Platform for the Formation of Human Adipose-Derived Stem Cell aggregates.

Javad Hatami,Sandra Silva,Mariana Oliveira,Rui Reis,Rui Costa,João Mano

doi:10.3390/polym9090440

Abstract

The construction of multilayered films with tunable properties could offer new routes to produce biomaterials as a platform for 3D cell cultivation. In this study, multilayered films produced with five bilayers of chitosan and alginate (CHT/ALG) were built using water-soluble modified mesyl and tosyl–CHT via layer-by-layer (LbL) self-assembly. NMR results demonstrated the presences of mesyl (2.83 ppm) and tosyl groups (2.39, 7.37 and 7.70 ppm) in the chemical structure of modified chitosans. The buildup of multilayered films was monitored by quartz-crystal-microbalance (QCM-D) and film thickness was estimated using the Voigt-based viscoelastic model. QCM-D results demonstrated that CHT/ALG films constructed using mesyl or tosyl modifications (mCHT/ALG) were significantly thinner in comparison to the CHT/ALG films constructed with unmodified chitosan (p < 0.05). Adhesion analysis demonstrated that human adipose stem cells (hASCs) did not adhere to the mCHT/ALG multilayered films and formed aggregates with sizes between ca. 100–200 µm. In vitro studies on cell metabolic activity and live/dead staining suggested that mCHT/ALG multilayered films are nontoxic toward hACSs. Multilayered films produced via LbL assembly of ALG and off-the-shelf, water-soluble modified chitosans could be used as a scaffold for the 3D aggregates formation of hASCs in vitro.

Highlights

Mesenchymal stem cells (MSCs), which are capable of self-renewal and multilineage differentiation, are becoming increasingly important for the development of cell therapeutics in regenerative medicine
The results demonstrated that water solubility can be obtained by modification of chitosan with mesyl and tosyl groups
We suggest the use use of of biomaterials for tissue engineering and regenerative medicine

Summary

Introduction

Mesenchymal stem cells (MSCs), which are capable of self-renewal and multilineage differentiation, are becoming increasingly important for the development of cell therapeutics in regenerative medicine. Adipose-derived stem cell (ASC) represents a very attractive cell type of MSCs that are accessible, abundant and rich source of adult stem cells [1]. Polymers 2017, 9, 440 specific conditions [2] These potentials, along with their easy accessibility, made ACS a good candidate for many cell-based therapies. ASCs could represent an ideal candidate for a 3D culture of MSCs because of their abundant autologous cells and the ease of their access. Different techniques, such as non-adherent culture condition, nutrient deprivation, air–liquid surface, spinner flask and hanging drop, have been used to form 3D spheroids [4,6,7]

Methods

Results

Conclusion