Human hepatocytes loaded in 3D bioprinting generate mini-liver

BACKGROUND:Because of an increasing discrepancy between the number of potential liver graft recipients and the number of organs available, scientists are trying to create artificial liver to mimic normal liver function and therefore, to support the patient’s liver when in dysfunction. 3D printing technique meets this purpose. The present study was to test the feasibility of 3D hydrogel scaffolds for liver engineering.METHODS:We fabricated 3D hydrogel scaffolds with a bioprinter. The biocompatibility of 3D hydrogel scaffolds was tested. Sixty nude mice were randomly divided into four groups, with 15 mice in each group: control, hydrogel, hydrogel with L02(cell line HL-7702), and hydrogel with hepatocyte growth factor(HGF). Cells were cultured and deposited in scaffolds which were subsequently engrafted into livers after partial hepatectomy and radiation-induced liver damage(RILD). The engrafted tissues were examined after two weeks. The levels of alanine aminotransferase(ALT), aspartate aminotransferase(AST), albumin, total bilirubin, CYP1A2, CYP2C9, glutathione S-transferase(a-GST), and UDP-glucuronosyl transferase(UGT-2) were compared among the groups. Hematoxylin-eosin(HE) staining and immunohistochemistry of cK it and cytokeratin 18(CK18) of engrafted tissues were evaluated. The survival time of the mice was also compared among the four groups.RESULTS:3D hydrogel scaffolds did not impact the viability of cells. The levels of ALT, AST, albumin, total bilirubin, CYP1A2, CYP2C9, a-GST and UGT-2 were significantly improved in mice engrafted with 3D scaffold loaded with L02 compared with those in control and scaffold only(P<0.05). HE staining showed clear liver tissue and immunohistochemistry of c Kitand CK18 were positive in the engrafted tissue. Mice treated with 3D scaffold+L02 cells had longer survival time compared with those in control and scaffold only(P<0.05).CONCLUSION:3D scaffold has the potential of recreating liver tissue and partial liver functions and can be used in the reconstruction of liver tissues.