Characterization of hepatocytes and hUCB-MSCs and Fabrication of 3D printed alginate structure. (A). (a) Confirmation of hepatocyte morphology, (b) fluorescence expression in CAG-dsRed primary hepatocytes, (c) Alb (green), AFP(red), (d) CK18 (green), and CYP1A2 (red). (e) Morphology of hUCB-MSCs, (f) GFP-tagged, and (g and f) confirmation of differentiation ability into adipogenic and osteogenic linages of hMSCs. Bars, 50 μm (c-d), 100 μm (a-b, e-f), and 200 μm (g-h). (B). A schematic diagram of a 3D printed architecture composed of mouse primary hepatocytes and human MSCs. The 3D hepatic architecture manufactured to be 25 mm x 25 mm in size and composed of 5 layers. (C). Distribution of CAG-dsRed primary hepatocytes and GFP-tagged hMSCs in the 3D hepatic architecture under fluorescence microscopy at day 1. Bars, 100 μm.