| 초록 |
Development of chemically defined culture platform is essential for regenerative medicine using human Embryonic Stem Cell (hESC). Numerous materials such as proteins, peptides, and synthetic polymers have been explored as chemically defined substrates, however, the development of inexpensive, scalable, and chemically defined material still remains as a challenging subject. So far, studies about functional polysaccharides as potential candidates for the chemically defined platform to culture hESCs have been rather under performed. Here, we introduce a new class of polysaccharide derivative for feeder-free maintenance of hESC. Dopamine was conjugated to heparin by which the conjugated dopamine plays an important role in robust surface adhesion inspired by marine mussels. The dopamine conjugated heparin (heparin-catechol) easily functionalizes polystyrene dishes to from thin nanolayer whereas chemically unmodified heparin (as a control) was not adsorbed on the culture dish. On the heparin-catechol-coated substrate, 80 % of the colonies robustly adhered and maintained expressions of pluripotency markers, Oct4, Sox2, and Nanog even after four passages. Interestingly, we found that the expressions of differentiation markers for three-germ layers were more suppressed for heparin-dopamine-coated dishes than Matrigel-functionalized ones. More importantly, when the heparin-dopamine was coated with collagen type Ι, it was able to support long-term growth of hESC over 18 passages. The hESCs obtained from eighteen-passaged samples maintained their pluripotency, exhibited normal karyotype, and showed significant suppression of three-germ layer differentiations. We propose that hepamine played a crucial role in suppressing the differentiation of hESC during such a long-period culture on the heparin-dopamine/collagen-functionalized substrate. |
