Research progress in lineage tracing to explore hepatic parenchymal cell regeneration and repair mechanisms / 中华肝脏病杂志

Hepatic parenchymal cells are a type of liver cells that performs important functions such as metabolism and detoxification. The contribution of hepatic parenchymal cells, bile duct cells, and hepatic stem/progenitor cells to new hepatic parenchymal cells in the process of liver injury repair has become a controversial issue due to their strong proliferation ability. Lineage tracing technology, which has emerged in the past decade as a new method for exploring the origin of cells, can trace specific type of cells and their daughter cells by labeling cells that express the specific gene and their progeny. The article reviews the current literature on the origin and contribution of hepatic parenchymal cells by this technique. About 98% of new hepatic parenchymal cells originate from the existing hepatic parenchymal cells during liver homeostasis and after acute injury. However, under conditions of severe liver injury, such as inhibition of hepatic parenchymal cell proliferation, bile duct cells (mainly liver stem/progenitor cells) become the predominant source of hepatic parenchymal cells, contributing a steady increased hepatocyte regeneration with the extension of time.

The Induced Differentiation of Hepatic Stem/Progenitor Cells from Human Umbilical Cord Blood / 医学研究杂志

Objective To study the possibility of umbilical cord blood mononuclear cells(UCB MNCs) having polydifferential potention to be induced and differentiated into hepatic stem/progenitor cells.Methods Collecting 32 cases fresh UCB from mature delivery,UCB MNCs were isolated by density-step centrifugal effect and were randomly divided into two groups:(1) control group 8 cases:the basic medium supplemented without cytokines;(2) trial group 24 cases,divided into four groups randomly,and the experimental results were detected at 0d,7d,14d,21d,respectively.The basic medium supplemented with various combinations of growth /differentiation factors(FGF-1,FGF-2,LIF,SCF,HGF,and OSM);cell morphological change was observed,hALBmRNA was examinated using RT-PCR methods,the expressions of ALB、CK18、CK19 were detected by immunohistochemistry.Results In trial group cell number increased,cell volume enlarged,refraction strong,polymorphic cells(mostly oval cells) appeared and obviously attached on the culture dishes.The expression of CK18、CK19、ALB were positive by immunohistochemistry,and the level of hALBmRNA improved along with the culture time.Conclusions UCB MNCs can be induced and differentiated into hepatic stem/progenitor cells in vitro.Human umbilical cord blood mononuclear cells may be a new source of transplantable hepatic stem/progenitor cells and hepatocytes.