ObjectiveTo construct large block of engineered liver tissue by co-culture of fibroblasts and hepatocytes on collagen hydrogels in vitro and do in vivo implantation research. MethodsSilastic mould was prepared using three-dimensional printing technology. The collagen hydrogel scaffold was prepared by collagen hydrogel gel in the silicone mould and was removed. Sprague Dawley rat lung fibroblasts were co-cultured with primary hepatocytes at a ratio of 0.4:1 on the collagen hydrogel scaffold to construct large block of engineered liver tissue in vitro (group B), and primary hepatocytes cultured on the collagen hydrogel scaffold served as control group (group A). The cell morphology was observed, and the liver function was tested at 1, 3, 7, 14, and 21 days after culture. The rat model (n=24) of hepatic cirrhosis was made by subcutaneous injection of carbon tetrachloride. And in vivo implantation study was carried in cirrhosis rat model. The phenotypic characteristics and functional expression of hepatocytes were evaluated at 3, 7, 14, 21, and 28 days after implantation. ResultsIn vitro results indicated that hepatocytes in group B exhibited compact polyhedral cells with round nuclei and high expression of liver function. Moreover, cells aggregated to the most at 7 days. Album production and urea synthesis incresed significantly when compared with group A (P<0.05). In vivo results showed hepatocytes in group B survived for 28 days, and albumin production and urea synthesis were significantly increased. In addition, hepatocytes showed an aggregated distribution and cord-like structures, which was similar to normal liver tissue. ConclusionThe large block of engineered liver tissue constructed by co-cultured cells can form tissue similar to normal liver tissue in vivo, and survive for a long time, laying foundations for building more complete engineered liver tissue in the future.