One-step stem cell cluster culture process using hydrophilic tapered stencil mask

This paper reports on new device for 3D cluster formation of stem cells under combinatorial seeding conditions - cell population and density. The device has an array of tapered holes of various sizes, and the surface is modified with hydrophilic polymer to prevent cell adhesion. Thus, the cells seeded onto the device aggregate in the areas defined by the holes. By varying the shape of the holes, cluster cultures can be performed under different conditions at one time. The device is easily incorporated into conventional cluster culture protocols by just placing the device onto an arbitrary culture substrate. Combinatorial cluster formation of stem cells derived from pancreatic duct was successfully demonstrated on ultra low attachment surface and Matrigel. The device should be useful for one-step combinatorial analysis to find optimal cluster culture conditions for various types of cells, and the more, for mass production of standardized embryonic body (EB) necessary in tissue engineering research.