Response of Bone Marrow-derived Stem Cells (MSCs) on Gelatin/Chitosan and Gelatin/Chitooligosaccharide films

Abstract

In this study, we investigated the effects of gelatin, chitosan and chitooligosaccharide on the biological response of bone marrow-derived stem cells (MSCs). Chitosan (CH, MW 1,000 kDa) and chitooligosaccharide (COS, MW 1.4 kDa) were produced from alkaline deacetylation and free radical degradation with hydrogen peroxide (H2O2) processes, respectively. Films of gelatin/CH and gelatin/COS with various blending ratios were prepared by solution casting and dehydrothermal crosslinking techniques. MSCs isolated from 3-weekold Wistar rat were cultured on the films to assess cell attachment, proliferation and osteogenic differentiation including alkaline phosphatase (ALP) activity and calcium content. On the 1st day after seeding, it was noticed that spreading areas of MSCs attached on blended gelatin/CH and gelatin/COS films were larger than those on pure gelatin, CH and COS films. It was observed that the morphology of MSCs attached on pure CH films was round compared to those on pure gelatin and COS. The number of MSCs attached and proliferated on gelatin/ CH and gelatin/COS films, particularly for the films containing 70% CH and COS, were significantly higher than those on pure gelatin, CH and COS films. Along period of culture, the lowest number of MSCs was found on pure CH film, implying the toxicity of CH. After 7 days of culture under osteogenic differentiation condition, higher amount of ALP and calcium released from MSCs cultured on pure gelatin film were noticed. It was interesting that less ALP and calcium were observed on pure COS film compared to CH film. It could be concluded from the results that chitooligosaccharide was more favorable to the proliferation of MSCs compared to high molecular weight chitosan. On the other hand, high molecular weight chitosan had higher potential to promote osteogenic differentiation of MSCs than chitooligosaccharide.