Tissue Eng Part A. 2018 May 30. doi: 10.1089/ten.TEA.2018.0020. [Epub ahead of print]

A Fluidic Culture Platform for Spatially Patterned Cell Growth, Differentiation, and Cocultures.

Lembong J¹, Lerman MJ², Kingsbury TJ³, Civin CI⁴, Fisher JP⁵.

Abstract

Stem cell cultures within perfusion bioreactors, while efficient in obtaining cell numbers, often lack the similarity to native tissues and consequently cell phenotype. We develop a three-dimensional (3D)-printed fluidic chamber for dynamic stem cell culture, with emphasis on control over flow and substrate curvature in a 3D environment, two physiologic features of native tissues. The chamber geometry, consisting of an array of vertical cylindrical pillars, facilitates actin-mediated localization of human mesenchymal stem cells (hMSCs) within ~200 µm distance from the pillars, enabling spatial patterning of hMSCs and endothelial cells (ECs) in cocultures and subsequent modulation of calcium signaling between these two essential cell types in the bone marrow microenvironment. Flow-enhanced osteogenic differentiation of hMSCs in growth media imposes spatial variations of ALP expression, which positively correlates with local shear stress. Proliferation of hMSCs is maintained within the chamber, exceeding the cell expansion in conventional static culture. The capability to manipulate cell spatial patterning, differentiation, and 3D tissue formation through geometry and flow demonstrates the culture chamber's relevant chemo-mechanical cues in stem cell microenvironments, thus providing an easy-to-implement tool to study interactions among substrate curvature, shear stress, and intracellular actin machinery in the tissue engineered construct.