Objective:To investigate the mechanism of improving liver injury by enhancing the abundance of Akkermansia mu-ciniphila(AKK bacteria)with hepatocyte-specific Yap1 knockout during PD-1 monoclonal antibody treatment.Methods:Hepatocyte-specific Yap1 knockout mice(genotype Yap1Flox/Flox;albumin-Cre,labeled as Yap1LKO)and control mice(genotype Yap1Flox/Flox,labeled Yap1Flox),aristolocholic acidⅠ(AAⅠ)and CCl4 were used to induce liver injury,Yap1LKO mice and Yap1Flox mice were randomly di-vided into control group and PD-1 monoclonal antibody group.After the intervention,real-time PCR detected changes in the abun-dance of AKK bacteria in the fecal microbial DNA of mice,16S rRNA gene sequencing further analyzes intestinal flora changes,the livers of mice were made into wax blocks for HE staining to observe the histopathological changes of the liver.Results:Yap1Flox mice exhibited balloon-like edema degeneration of hepatocytes and infiltration of inflammatory factors in the manifold area,compared with Yap1Flox mice,Yap1LKO mice had reduced the abundance of AKK bacteria in the intestine,fibrosis of the liver,and the degree of dam-age was more serious;PD-1 monoclonal antibody treatment alone did not increase the abundance of AKK bacteria in the intestines of mice,and fibrosis appeared in the liver;however,the abundance of intestinal AKK bacteria in Yap1LKO mice treated with PD-1 mono-clonal antibody increased,the ratio(F/B value)of Firmicutes to Bacteroides at the phylum level decreased,and the morphology of he-patocytes returned to normal and the degree of liver damage decreased.Conclusion:In AAⅠ and CCl4 induced liver injury mice,he-patocyte-specific Yap1 knockout reduced the abundance of AKK bacteria in the intestine,and the degree of liver injury was more se-vere than that in Yap1Flox mice.When treated with PD-1 monoclonal antibody,hepatocyte-specific Yap1 knockout could increase the abundance of AKK bacteria in the intestine,change the composition of intestinal flora,maintain intestinal homeostasis and ameliorate liver injury.

Objective:To investigate the mechanism of improving liver injury by enhancing the abundance of Akkermansia mu-ciniphila(AKK bacteria)with hepatocyte-specific Yap1 knockout during PD-1 monoclonal antibody treatment.Methods:Hepatocyte-specific Yap1 knockout mice(genotype Yap1Flox/Flox;albumin-Cre,labeled as Yap1LKO)and control mice(genotype Yap1Flox/Flox,labeled Yap1Flox),aristolocholic acidⅠ(AAⅠ)and CCl4 were used to induce liver injury,Yap1LKO mice and Yap1Flox mice were randomly di-vided into control group and PD-1 monoclonal antibody group.After the intervention,real-time PCR detected changes in the abun-dance of AKK bacteria in the fecal microbial DNA of mice,16S rRNA gene sequencing further analyzes intestinal flora changes,the livers of mice were made into wax blocks for HE staining to observe the histopathological changes of the liver.Results:Yap1Flox mice exhibited balloon-like edema degeneration of hepatocytes and infiltration of inflammatory factors in the manifold area,compared with Yap1Flox mice,Yap1LKO mice had reduced the abundance of AKK bacteria in the intestine,fibrosis of the liver,and the degree of dam-age was more serious;PD-1 monoclonal antibody treatment alone did not increase the abundance of AKK bacteria in the intestines of mice,and fibrosis appeared in the liver;however,the abundance of intestinal AKK bacteria in Yap1LKO mice treated with PD-1 mono-clonal antibody increased,the ratio(F/B value)of Firmicutes to Bacteroides at the phylum level decreased,and the morphology of he-patocytes returned to normal and the degree of liver damage decreased.Conclusion:In AAⅠ and CCl4 induced liver injury mice,he-patocyte-specific Yap1 knockout reduced the abundance of AKK bacteria in the intestine,and the degree of liver injury was more se-vere than that in Yap1Flox mice.When treated with PD-1 monoclonal antibody,hepatocyte-specific Yap1 knockout could increase the abundance of AKK bacteria in the intestine,change the composition of intestinal flora,maintain intestinal homeostasis and ameliorate liver injury.

BACKGROUND: There is no study addressing transplantation of umbilical cord mesenchymal stem cells for the treatment of spinocerebellar ataxia.OBJECTIVE: To study the clinical effect of human umbilical cord stem cells transplantation in the treatment of autosomal dominant spinocerebellar ataxias. METHODS: Spinocerebellar ataxias patients selected from Stem Transplantation Center of the 455 Hospital of Chinese PLA were treated with umbilical cord mesenchymal stem cells transplantation via intrathecal injection. The number of umbilical cord mesenchymal stem cells was 107 per transplantation, once per week, for 4 weeks.RESULTS AND CONCLUSION: Both the total score of the International Cooperative Ataxia Rating Scale and Activities of Daily Living score were significantly decreased at 1 month after transplantation compared with before treatment (P < 0.05). The nerve function was significantly improved and the total effective rate was up to 16.7%. Experimental findings indicate that, transplantation of umbilical cord mesenchymal stem cells via intrathecal injection is a feasible and effective treatment to ameliorate the clinical efficacy of spinocerebellar ataxias patients and improve their quality of life.