Complement Mechanism Of Endometritis In Dairy Cows Based On Proteomics And Transcriptomics

Endometritis is a common disease postpartum with high morbidity.Endometritis usually has negative influence on breeding performance,and causes a serious economic loss in dairy farming industry.To explore molecular pathological change in cows with endometritis,in this study,we researched plasma proteomics,uterus proteomics and transcriptomics using high through sequencing respectively,and verified omics results using cellular inflammatory model in vitro.The research findings showed as follow:1.Compared with normal dairy cows,there is 137 plasma differentiall expressed proteins(DEPs)in cows with endometritis,as well as 49 were up-regulated and 88 were down-regulated.Results of bio-informatics analysis showed complement and coagulation cascades became the main biological pathway involving the most DEPs with a ratio of 13%.ELISA results showed that serum C4,C7,C9,C3 a,C5a and Ig G were significantly higher than a normal levels.It demonstrated that complement and coagulation system was activated in blood of the endometritis cows,and participated the pathological process of endometritis.2.We graded clinical cases by histopathological study as moderate endometritis(M)and severe endometritis(S).Uterine proteomics and transcriptomic research showed there is 259 DEPs and 139 DEGs in M group,and 434 DEPs and 207 DEGs in S group.Result of DEPs bio-informatics analysis showed that complement and coagulation cascades is the main biological pathway in both groups,and ribosome is the most prominent pathway in S group.Result of DEGs bio-informatics analysis showed that with complement and coagulation cascades is the most significant pathway in both of M and S groups.Further analysis showed numbers of DEPs and DEGs of complement are positive correlative with endometrial inflammation intensity.Number of DEPs of coagulation is also positive correlative with the inflammation intensity,but it seems coagulation genes expression fail to correlate with endometritis.It demonstrated that complement and coaguation cascades is an important pathway correlating with endometritis pathology,and endometritis induces differentially expression of complement,but doesn't affect expression of coagulation in endometrum,maybe coagulation proteins was from blood circulation.3.Endometrial epithelial cell and stromal cells are able to express complement genes induced by LPS in vitro,including C1 QC,C2,C4,C5,CFB,CFH,CFD and MCP,as well as complement proteins of C3 a and C9.Moreover,endometrial cell doesn't express chemotactic factor IL-8,only express little CXCR2 and much CXCL5.The results demonstrated that endometrial cells can express genes of complement as well as some complement proteins.As known endometrial cells is the first organism for contacting and interacting with invading pathogens in uterine cavity.Thus,on the condition of inflammation,endometrial cells express complement may has dual functions with killing pathogens and chemotaxis to immune cells.In summary,this paper studied plasma proteomics and uterine proteomics and transcriptomics using high through sequencing technologies.It is the first time to discover that altered expression and activation of complement is a main pathway that is correlative with pathology course of cow's endometritis.The research results provide some important data that is helpful to understand pathological mechanism and control the disease.