Human mesenchymal stem cell culture on heparin-based hydrogels and the modulation of interactions by gel elasticity and heparin amount

Human adipose-derived stem cells (hADSCs) are a promising cell source for tissue engineering and regenerative medicine with no ethnical issue and easy access of large quantities. Conventional surfaces for hADSC culture, such as tissue culture plates (TCPs), do not provide optimal environmental cues, leading to limited expansion, loss of pluripotency and undesirable differentiation of stem cells. The present study demonstrated that heparin-based hydrogels without additional modification provided an excellent surface for adhesion and proliferation of hADSCs, which were further tunable by both the amount of heparin (in a positive way) and the elasticity of hydrogel (in a negative way). The optimized heparin-based hydrogel could selectively modulate the adhesion of hADSCs and human bone marrow stem cells (but not all kinds of cells), and resulted in a significant increase in cell proliferation compared to TCP. Furthermore, in terms of the maintenance of pluripotency and specific differentiation, heparin-based hydrogel was much superior to TCP. The selective binding and proliferation of human mesenchymal stem cells on heparin-based hydrogel over other hydrogels were largely mediated by integrin β1 and selectin, and these superior characteristics were observed regardless of the presence of serum proteins in the culture medium. Consequently, heparin-based hydrogel could be a powerful platform for cultivation of mesenchymal stem cells in various applications.