HGF/R-spondin1 Rescues Liver Dysfunction Through The Induction Of Lgr5~+ Liver Stem Cells

Liver disease is a world-wide disease that results in death,especially in China.Most liver diseases are chronic liver diseases,in which liver fibrosis plays a particularly important role.Currently there are no approved effective therapeutics for liver fibrosis yet.Therefore,exploring effective therapeutics for liver fibrosis may benefit most liver diseases,and bring significant social and economic benefits.In this study,using CCl4 induced mice chronic liver fibrosis model,the roles of Lgr5+ liver tissue stem cells in liver fibrosis processing is studied,and the possibilities of liver fibrosis treatment by inducing Lgr5+ liver tissue stem cells are explored.We found that Lgr5+ liver tissue stem cells are induced during liver fibrosis processing,and these cells are identified as liver stem cells.When we knocked Lgr5 down using adenovirus-mediated Lgr5 shRNAor Crispr/Cas9 technology,Lgr5+ liver tissue stem cells lose their organ-forming ability in vitro,and liver fibrosis become more severe in vivo.Whereas,Lgr5+ liver tissue stem cells transplantation attenuates liver fibrosis.These results provided evidence for the therapeutic effect of Lgr5+ liver stem cells in the treatment of liver.We further screened rHGF in combination with rRspo1 increasing Lgr5+ liver stem cells number both in vitro and in vivo.Intravenous injection of recombinant HGF proteins and Rspol proteins significantly attenuate liver fibrosis and recover liver functions.When Lgr5 was knocked down,intravenous injection of recombinant HGF proteins and Rspo1 proteins fail to atenuated liver fibrosis.These results showed that rHGF/rRspo1 could attenuate liver fibrosis by increasing the number of Lgr5+ liver stem cells.More importantly,we observed Lgr5+ liver stem cells in human liver fibrosis tissues,and once they are isolated,these cells are able to form organoids,and treatment with HGF/Rspo1 promotes their expansion.We suggest that Lgr5+ liver stem cells represent a valuable target for liver damage treatment,and that HGF/Rspol can be used to treat liver fibrosis clinically by promoting liver stem cell expansion..Our study explored the roles of Lgr5+ liver tissue stem cells in liver fibrosis processing and liver injury repairs.Liver fibrosis treatment using induction of endogenous liver Lgr5+ stem cells by administering soluble protein HGF/Rspol injections was proposed and preliminarily verified.Our research will provide new and effective therapeutic for liver fibrosis.This treatment would benefit a wide range of patients suffering from liver disease.Furthermore,our studies will deepen people's understanding ofthe characteristics of adult tissue stem cell self-renewal and stem cells based tissue damage repair/regeneration,expand the application range and application methods ofadult stem cells,and provide experiences for other organ/tissue injury repair diseases and aplastic diseases.