Increased susceptibility to apoptosis as a result of aging leads to a dramatic increase in liver repopulation by transplanted fetal liver stem/progenitor cells

Recently, we showed that normal adult rat liver can be replaced by transplanting fetal liver stem/progenitor cells (FLSPC). Liver repopulation occurs by cell competition between transplanted FLSPC and host hepatocytes during which the former replace the latter by inducing their apoptosis. In the present study, we compared the repopulation potential of FLSPC after their transplantation into rats of different ages (2, 6, 14 mo.). Embryonic day 14 (ED14) fetal liver cells from DPPIV+ F344 rats were transplanted into mutant DPPIV– F344 rats and 6 mo. later, we observed 4.5% liver replacement by transplanted FLSPC in…