5% of total unfractionated ED14 fetal liver cells.[17] We therefore estimated that 8 × 107 unfractionated fetal liver cells contained ∼2 × 106 “bipotential” FLSPCs, comparable to 2 × 106 mature hepatocytes. To obtain sufficient numbers of cells for these studies, we isolated unfractionated hepatic stem/progenitor cells from ED15 fetal livers.
While maintaining the TAA dose after cell transplantation into advanced fibrotic rat liver (Figs. 4, 5), levels of 35.7 ± 6.4% and 40.8 ± 10.3% repopulation were achieved with FLSPCs at 2 and 4 months, respectively (n = 4/4). FLSPCs differentiated into hepatocytes (Fig. 4A) and bile duct cells. The large DPPIV+ clusters of hepatocytes CH5424802 concentration typically had DPPIV+ bile ducts along the edges of fibrous septae (Fig. 4). In some cases, DPPIV+ bile this website ducts extended into surrounding DPPIV-negative regions (Fig. 4B), presumably resulting from a stimulus for bile duct proliferation in the injured liver. The cells formed large DPPIV+ clusters with extensive tissue replacement (Fig. 4C,E). In comparison, substantial numbers of transplanted mature hepatocytes engrafted in the cirrhotic liver, proliferated long-term, and replaced diseased liver mass (Fig. 4A, right panels, 4D). However, liver repopulation levels with mature hepatocytes were
lower at 2 and 4 months after cell transplantation (8.3 ± 2.0% and 10.5 ± 3.2%, respectively; n = 3/4) compared to that obtained with FLSPCs (35.7 ± 6.4% and 40.8 ± 10.3%, respectively). Although there was higher repopulation with transplanted stem/progenitor cells, which indicates a higher engraftment or proliferation rate, our findings with mature hepatocytes also represent a significant new observation in the fibrotic liver. Simultaneous immunohistochemical analysis for DPPIV (CD26) and α-SMA (Fig. 5A) showed that DPPIV+ cell clusters derived from transplanted FLSPCs
completely replaced host hepatocytes selleck products within liver nodules surrounded by fibrous host tissue containing α-SMA+ cells (Fig. 5A, left panels), a phenomenon also observed after hepatocyte transplantation (Fig. 5A, upper right panel). Double-label immunohistochemistry for DPPIV (CD26) and Ki-67 (Fig. 5B) showed that FLSPC and hepatocyte-derived cell clusters contained actively proliferating cells for up to 4 months (Fig. 5B, middle and lower panels) and “competed” with proliferating host hepatocytes (Fig. 5B, upper right panel). Furthermore, DPPIV and G6Pase expressing hepatocytic cells were detected at 2 and 4 months after transplantation of FLSPCs or hepatocytes (Fig. 5C), demonstrating hepatocyte-specific metabolic activity of transplanted cells. Since we showed that FLSPCs can form cell clusters in the fibrotic liver without PH (Fig.