Dependence of Wnt3a Release on the Nano-feature Size of Culture Substrate

M.K. Kim, B. Gi Park, K.B. Lee
Korea University, KR

Keywords: nanopattern, paracrine, gradient, AAO

Summary:

In this study, we fabricated nanoporous anodic aluminum oxide (AAO) with a gradient of pores of which the diameters varied from 120nm to 300nm in a fixed 440 nm center-to-center distance. Using an AAO with the gradient as a mold, high-fidelity inverse replicas were produced on polystyrene (PS) sheets through thermal nanoimprinting process, so that the mold could leave a gradient of nanoscale features on the PS sheets. This nanopatterned PS sheets were used as a cell culture substrate. Those were large (2cm×3cm) enough to investigate cellular responses. Onto them, we cultured Mouse L-Wnt3A cells (L cells) (CRL-2647, ATCC, USA) which secret high amounts of wnt3a protein. After 3 days of culture, while cellular activities were similar regardless of nano-feature size on the PS pattern, a significant difference was found in the level of wnt3a protein release among the different sections of gradient. The amount of wnt3a increases as the size of the nano-features in the gradient increases and the release of wnt3a protein in the flat control was between those of regions with small and large nano-features. This result indicates the wnt3a release of L cells depends on the nanometer scale feature size of the substrate.