Two applications have been used to demonstrate this technol-

ogy. A liver model based around the HepG2 hepatocellular carci-

noma cell line was initially developed due to the highly vascularized

nature of the liver suggesting it would benefit from such a system.

Further work demonstrated the utility of the system for the culture

of an intestinal model, using the Caco-2 cell line cocultured with

fibroblasts [8].

For the liver model a thicker tissue-like layer of HepG2 cells is

formed on the surface of the Alvetex^® Strata in perfused conditions,

as can be visualized using Hematoxylin and eosin (H&E) staining

of tissue sections (Fig. 4a). The high viability of this tissue is

supported by the results of an MTT assay (Fig. 4b, c). Immunoflu-

orescent analysis of these models demonstrates that the levels of key

Fig. 4 H&E staining and metabolic function of HepG2 grown on Alvetex Strata in static and perfusion. (a)

HepG2 cells were grown on Alvetex Strata in static and perfusion with the formation of a thicker cell layer and

greater invasion in perfusion as shown by the H&E stain. Scale bars are 100 μm. (b) After carrying out an MTT

assay the membranes show the even distribution of viable cells across the membrane. (c) Results of the MTT

assay for HepG2 on Alvetex Strata in static and perfused conditions show evidence of increased cell

metabolism in perfusion. Values are mean
SEM, *** ¼ p < 0.05

Applying Stirred Perfusion to 3D Tissue Equivalents to Mimic the Dynamic In. . .

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