Culturing of transgenic mice liver tissue slices in three-dimensional microfluidic structures of PEG-DA (poly(ethylene glycol) diacrylate)

The bioreactors with an array of multiple wells favoring the maintenance of the three-dimensional (3-D) liver tissue cultures under continuous perfusion have been developed. All bioreactors were fluidically connected to each other. Each bioreactor in the array contains the poly(ethylene glycol) diacrylate (PEG-DA) microstructures, cultured with the mesothelial cells that support the formation of 3-D environment. The mesothelial cells surrounding liver tissue whose primary functions in vivo are to provide a protective adhesive surface and help in tissue repair. The tissue units were continuously perfused with cell culture medium in the bioreactor. After twelve days of culture, the liver tissue surrounded by the mesothelial cells seeded in the perfused multiwell reactor remained functionally viable as assessed by H&E (hematoxylin and eosin) stain and TUNEL (Terminal deoxynucleotidyl transferase (dUTP) nick end labeling) assay examination. The liver tissue shows intact architecture and enhanced viability compared with those in conventional culture dish and incubation systems. The hepatitis B surface antigen (HBsAg) expression of the liver tissue cultured in our bioreactor was also much better when compared to the conventional static culture method. The use of primary liver sample provides more relevant experimental system and potentially replaces the animal based models.