Publications [#381397] of Seog Oh

Papers Published

1. Yap, LYW; Li, J; Phang, IY; Ong, LT; Ow, JZ-E; Goh, JCH; Nurcombe, V; Hobley, J; Choo, ABH; Oh, SKW; Cool, SM; Birch, WR, Defining a threshold surface density of vitronectin for the stable expansion of human embryonic stem cells., Tissue engineering. Part C, Methods, vol. 17 no. 2 (February, 2011), pp. 193-207 [doi]
   (last updated on 2026/01/19)

   Abstract:
   Current methodology for pluripotent human embryonic stem cells (hESCs) expansion relies on murine sarcoma basement membrane substrates (Matrigel™), which precludes the use of these cells in regenerative medicine. To realize the clinical efficacy of hESCs and their derivatives, expansion of these cells in a defined system that is free of animal components is required. This study reports the successful propagation of hESCs (HES-3 and H1) for > 20 passages on tissue culture-treated polystyrene plates, coated from 5 μg/mL of human plasma-purified vitronectin (VN) solution. Cells maintain expression of pluripotent markers Tra1-60 and OCT-4 and are karyotypically normal after 20 passages of continuous culture. In vitro and in vivo differentiation of hESC by embryoid body formation and teratoma yielded cells from the ecto-, endo-, and mesoderm lineages. VN immobilized on tissue culture polystyrene was characterized using a combination of X-ray photoemission spectroscopy, atomic force microscopy, and quantification of the VN surface density with a Bradford protein assay. Ponceau S staining was used to measure VN adsorption and desorption kinetics. Tuning the VN surface density, via the concentration of depositing solution, revealed a threshold surface density of 250 ng/cm², which is required for hESCs attachment, proliferation, and differentiation. Cell attachment and proliferation assays on VN surface densities above this threshold show the substrate properties to be equally viable.