Background and Objective: Mesenchymal stem cells (MSCs), particularly bone MSCs
(BMSCs) offer great potentials for targeted therapeutic applications owing to their migratory and
differentiation capacities. Significant advances have been achieved in the differentiation of hepatocyte
or hepatocyte-like cells both in vitro and in vivo. However, there is limited knowledge on the
differentiation of BMSCs into bipotential hepatic progenitor cells or cholangiocyte. This study reviews
the potentials and advances in using MSCs as vehicles for targeted drug delivery and proposes
a new method for the induction of differentiation in rat BMSCs into hepatic progenitor cells in
vitro and assesses the differential and migratory capacities.
Methods: The BMSCs of Sprague Dawley (SD) rats were harvested from the femur and the tibiae
of the rats. After isolation and culturing, BMSCs from Passage 1 were used for the study. The in
vitro differentiation of the hepatic progenitor cells was performed using a 2-step induction approach
after 5-day serum deprivation from the BMSCs and culturing in Dulbecco's modified eagle
medium. Spontaneous in vitro differentiation of BMSCs was examined in the absence of growth
factors for 15 days as control treatment. Hepatocytes differentiation was achieved by exposing the
culture to collagen type I-coated plates. Cholangiocytes differentiation was achieved with replating
the BMC-HepPCs on a layer of Matrigel. Immunofluorescence was conducted on twelve-well
plates to determine cell differentiations. Real-Time Quantitative Reverse Transcription PCR (qRTPCR)
was used to determine the total RNA extracted using the Trizol LS reagent. In the hepatocyte
differentiation group, after periodic acid-schiff (PAS) staining for glycogen, inverted microscope
was used to determine differentiations and undifferentiated BMC-HepPCs served as controls.
The amount of low-density lipoprotein (LDL) uptake by the BMSCs-derived hepatocytes was assessed
using fluorescence microscopy. The secretion of rat albumin was quantified using a quantitative
Results: Differentiation induction is indicative of the sequential supplementation of sodium butyrate
and cytokines, which are involved in the embryonic development of the mammalian liver.
Hepatic progenitor cells, derived from bone marrow, can be differentiated bidirectionally in vitro
into both hepatocyte and cholangiocyte cell-lines. The differentiated cells, including hepatic progenitor
cells, hepatocytes, and bile duct-like cells, were identified and analyzed at mRNA and protein
Conclusion: Our findings show that BMSCs can be utilized as novel bipotential hepatic progenitor
cells and thereby for hepatobiliary disease treatment or hepatobiliary tissue-engineering.