Characterization of Matrigel interfaces during defined human embryonic stem cell culture.

Differences in attachment, proliferation, and differentiation were measured for human embryonic stem (hES) cells cultured on various substrata coated with Matrigel, a blend of extracellular matrix proteins derived from murine tumor cells. The authors observed that hES cells attach and grow poorly on Matrigel adsorbed onto polystyrene, while they proliferate when exposed to Matrigel adsorbed onto glass or oxygen plasma treated polystyrene (e.g., "tissue culture" treated polystyrene). Furthermore, hES cells grown on the Matrigel-coated tissue culture polystyrene are less likely to differentiate than those grown on the Matrigel-coated glass. To assess the mechanism for these observations, they replicated the cell culture interface in a quartz crystal microbalance with dissipation monitoring. In addition, they used ellipsometry and scanning electron microscopy to determine the thickness and topography of Matrigel on the varying surfaces. Matrigel formed a viscoelastic multilayer with similar thickness on all three surfaces; however, the network structure was different, where the adsorbed proteins formed a globular network on polystyrene, and fibrillar networks on the hydrophilic substrates. Matrigel networks on glass were denser than on oxygen plasma treated polystyrene, suggesting that the density and structure of the Matrigel network affects stem cell differentiation, where a denser network promoted uncontrolled hES cell differentiation and did not maintain the self-renewal phenotype.