The Study On The Mechanism Of Uterus Damages Induced By HEV Infection In BALB/c Mice

Hepatitis E virus(HEV)is a viral hepatitis pathogen that is transmitted through the gut and seriously endangers human health.HEV infections are mostly asymptomatic,self-limiting infections with low mortality rates,but the HEV mortality rates in pregnant women can be as high as 30%,and they can easily cause adverse pregnancy outcomes such as miscarriage,premature delivery and neonatal liver dysfunction.However,the pathogenesis of HEV in pregnant women is still unclear.The main work of this study is to establish a HEV infection model at the animal and cell levels,and to explore the molecular mechanism of reproductive function damage caused by HEV infection.The main contents include the following aspects:(1)An animal model of HEV infection in BALB/c females was constructed to provide an animal model for the study of HEV infection leading to adverse pregnancy.Meanwhile,exploring the infectivity of HEV in uterus tissues,and proposing evidence of HEV replication in uterine tissuesIn this paper,BALB/c mice were inoculated with the acute strain of genotype 4HEV,and HEV RNA positive was detected in feces and serum,successfully establishing an animal model of HEV infection.Experimental methods such as RT-n PCR,RT-q PCR,immunohistochemistry and immunofluorescence were used to verify the infectivity of HEV in the uterine tissues of female BALB/c mice.At the same time,HEV infectivity was verified at the level of Hela cells.Results showed that HEV was able to replicate in the uterine tissues of the mouse female reproductive system,which laid a foundation for exploring the pathogenesis of HEV infection causing adverse pregnancy.(2)HEV infection of BALB/c female mice during the same period of estrus are still infertile,excluding the effects of physiological cycles on infertility caused by HEV infectionIn this paper,the estrus of BALB/c mice was induced by the use of contemporaneous estrous reagents(Serum Gonadotrophinum pro Injection and Chorionic Gonadotrophin for Injection),and then mated with normal BALB/c male mice to observe their reproductive situation and analyzed the effect of HEV infection on the reproductive ability of BALB/c female mice.The results showed that the birth of mice reduced or infertile.(3)Preliminary analysis of damage to the female reproductive system caused by HEV infectionIn this paper,pathological methods,immunohistochemistry and immunefluorescence techniques are used to analyze the pathological damage of uterine tissues of BALB/c female mice infected with HEV,detected inflammatory factors,analyzed and synthesized the expression levels of hormone receptors and uterine related proteins to evaluate the damage of female reproductive system caused by HEV infection.(4)After the HEV is completely cleared,the female reproductive damage can be partially recoveredThrough pathological analysis,it was found that after HEV clearance,uterine damage caused by viral infection could be partially recovered,and there was no significant difference about the number of fetuses with the uninfected group.The results show that the uterine damage caused by acute HEV infection can be improved after the virus is cleared.The results of this study indicated that HEV can replicated in the uterus and caused uterine damage,resulting in reduced female fertility.Use animal models to demonstrated that HEV infection results in thinning of the uterine wall,shortening of uterine villi,and infiltration of a large number of inflammatory cells,resulting in decreased expression of estrogen receptors,and increased expression of cytokeratin-7,vimentin and vascular endothelial growth factor.These injuries may be an important cause of the reduced fertility of female BALB/c mice.The experiment also further analyzed the recovery of uterine injury after HEV clearance.It was found that after the recovery of acute HEV infection,the uterine injury was improved and the reproductive ability of female mice was restored.The model of HEV infection leading to female injury and the possible causes of uterine injury constructed in this study provide new perspectives and help for further exploring the pathogenesis of HEV,especially the adverse effects of HEV infection on pregnancy outcomes.