Growth and osteogenic differentiation of adipose-derived and bone marrow-derived stem cells on chitosan and chitooligosaccharide films

Very low molecular weight chitooligosaccharide (COS, 1.4 kDa) and high molecular weight chitosan (1000 kDa) were comparatively studied in terms of physical and biological characteristics. Thin films of COS, chitosan and gelatin were prepared and crosslinked by dehydrothermal treatment at 140 °C for 24 h. COS film presented more hydrophilic property than chitosan film. Behaviors of rat adipose-derived stem cells (ASCs) and bone marrow-derived stem cells (MSCs) were investigated on COS and chitosan films, comparing to those on gelatin film. The results on cell spreading suggested that both ASCs and MSCs preferred to attach on COS film than chitosan film with 6–7 times larger cell areas. Numbers of both stem cells proliferated on COS film were approximately 3-fold higher than those on chitosan film. In addition, COS film enhanced osteogenic differentiating potential of MSCs, as observed from the alkaline phosphatase activity and calcium deposition. Therefore, in this work, COS was shown to be a more favorable material for the growth and osteogenic differentiation of both ASCs and MSCs, compared to high molecular weight chitosan.