Abstract: Objective The aim of the present study is to investigate the effect of oncostatin M on differentiation of the AFP promoter-defined human hepatic progenitor cells (APHPs) in vitro. Methods The morphology of APHPs was observed by phase-contrast microscopy including the proliferation condition and OSM inducement. The properties of differentiated APHPs were detected after OSM treatment, which involved the albumin expression with immunofluorescence, the glycogen storage with periodic acid Schiff staining (PAS) and the subcellular structure with electron microcopy. Results Morphology of APHPs was changed after treated with OSM，the APHPs were able to form cluster from day 3 after OSM treatment, the aggregation of tissue-like structure was found from day 7 after inducement, Immunofluorescence results revealed that the tissue-like structure was strong expression of albumin, and PAS results displayed the differentiated APHPs obtained the function of glycogen accumulation. In electron micrographs, cell junction was found localized along the lateral membrane between cells in cultures of OSM. In addition, microvillis were appeared on one side of plasma membrane. Conclusions The APHPs acquired mature function and structure after OSM treatment in vitro.

Key words: hepatic progenitors, AFP, oncostatin M, cell differentiation