Proliferation and osteogenic differentiation of human mesenchymal stem cells on cross‐linked polypeptide multilayer films

Abstract

Polyelectrolyte multilayer film is an emerging method for substrate coating to regulate cellular behaviors. This material allows for modulation of thickness, stiffness, and adhesiveness. In this study, human mesenchymal stem cells (hMSCs) were cultured on polypeptide multilayer films built up by the alternate deposition of cationic poly‐L‐lysine (PLL) and anionic poly‐L‐glutamic acid (PLGA), cross‐linked with EDC/sulfo‐NHS, and coated with type I collagen. The in‐vitro degradation of the cross‐linked PLL/PLGA films in the presence or absence of hMSCs were followed by fluorimetry after labeling of the outermost PLL layer with FITC. Cell proliferation was measured by CyQuant proliferation assay and osteogenic differentiation was evaluated by q‐PCR of osteogenic specific genes such as ALP, OCN, and OPN. The results showed that these cross‐linked films, with or without hMSCs on top of them, were quite stable in the culture medium and not subjected to degradation at least for a few weeks. While hMSCs maintained similar attachment and spreading behavior regardless of layer number (1–6 layers) of films, they demonstrated better proliferation rate on even number layer of films, where the top layers are PLGA films. In addition, compared with cells cultured on polystyrene culture wells and treated with osteogenic induction medium, hMSCs cultured on 6‐layer cross‐linked PLL/PLGA films showed a significant increase in the osteogenic differentiation rate. Our observations indicate a feasible way to manipulate stem cell behavior on polypeptide multilayer films by changing the number of layers, the outermost polypeptide layer, and the concentration of cross‐linkers.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.