[Preliminary study on transdifferentiation of human amniotic epithelial cells and its intrasplenic transplantation].

Objective: The human amniotic epithelial cells (hAECs) are a recently identified new type of stem cells. It has previously been shown that hAECs express hepatocyte-related gene and possess intracellular features and functional properties of hepatocytes. The hAECs may be a candidate seed cell for liver regeneration. To research the survival and migration in vivo of hAECs via adeno-associated virus-mediated the green fluorescent protein gene (AAV-GFP) transfection, and to explore the expression of hepatocyte-like function.

Methods: Thirty nude mice (aging 6-8 weeks, half males and females, and weighing 20-22 g) were randomly divided into 3 groups (groups A, B, and C, n=10). The mice of groups A and C were made the 2/3 partial hepatectomy model, and the mice of group B underwent open abdominal operation without hepatectomy. The hAECs transfected by AAV-GFP were transplanted into the inferior end of the spleen in groups A and B with a cell density of 5 x 10(6)/mL and a volume of 0.2 mL; the same volume of normal saline was injected in group C. At 4 hours, the nude mice were sacrificed and the samples of liver, spleen, heart, lung, brain, and kidney were harvested and the general observation, histological observation, and immunofluorescence detection were performed for the hAECs survival, migration, and the functional properties of hepatocytes.

Results: No tumor tissue was found in liver and spleen of 3 groups, and HE staining showed no tumor cells. There were a lot of roundlike and deeply-stained cells with less cytoplasm and large nucleus in the spleen and the liver of group A; no abnormal cells were found in liver and spleen of groups B and C and in kidney, heart, bung, and brain of groups A, B, and C. The GFP+ cells were detected in the spleen and liver of group A with expressing human albumin, but no GFP+ cells was found in liver and spleen of groups B and C and in heart, kidney, lung, and brain of groups A, B, and C.

Conclusion: AAV-GFPA infected hAECs transplanted into SCID nude mice with hepatectomy can keep the hepatocyte-like function. It will be beneficial to further identify their biological characteristics.