A Study On The Mechanism Of Autoinducer-2 Mediated Inter-kingdom Signaling Between Fusobacterium Nucleatum And Immunity Against Mice Intestinal Tumor

Objective:1 From the level of animal experiments,research the influence of autoinducer-2(AI-2)on intestinal tumor formation and gut microbiome.2 From the level of animal experiments,verify the influence of AI-2 on function of immunity against intestinal tumor and its molecular basis,observe the influence of stress on gut microbiome,reveal bidirectional regulation effect of AI-2 mediated inter-kingdom signaling on gut microbiome and immunity against intestinal tumor.3 From the level of animal experiments,explore the influence of AI-2 quorum sensing quenching and interference on intestinal tumor formation and gut microbiome.Methods:1 Bacterial culture:Fusobacterium nucleatum(Fn)culture was used for animal experiment,and Vibrio harveyi(V.Harvey)BB170 culture was used to detect AI-2 concentration.2 Mouse models:fifty male C57BL/6-ApcMin/+mice were randomly and equally divided into five groups:Ctr,Fn+D-rib,Fn,Fn+stress,Fn+stress+AMPT.Study the effects respectively of Fn,D-rib,stress,and AMPT on gut microbiome structure and intestinal tumor formation in mice.3 High-throughput sequencing of gut microbiome was used to observe the structure changes of gut microbiome in mice.4 The concentration of catecholamines(dopamine,norepinephrine,epinephrine)in mice intestinal tumor tissue and stool was detected by enzyme-linked immunosorbent assay.5 The pathological types of mice intestinal tumor tissue were detected by hematoxylin-eosin staining.6 Fluorescence in situ hybridization was used to detect the invasion of Fn in mice intestinal tumor tissue.7 The co-localization number of CD11c+ dendritic cells and NF-κB p65 in mice intestinal tumor tissue was detected by double immunofluorescence staining.Results:1 Fn may promote the formation of intestinal tumor in C57BL/6-ApcMin/+mice through AI-2.2 Stress may promote the formation of Fn-related intestinal tumors in C57BL/6-ApcMin/+mice through catecholamines.3 AI-2 concentration was positively correlated with the number and volume of intestinal tumors in mice.4 The concentrations of dopamine and norepinephrine were positively correlated with the number and volume of intestinal tumors in mice.5 The concentration of AI-2 was positively correlated with the concentration of catecholamines.6 Fn AI-2 and stress alter the structure of gut microbiome in mice.7 In the Fn-fed mice,Fn invaded the intestinal tumors,but were less abundant in the stool.8 AI-2 may promote the formation of intestinal tumors in C57BL/6-ApcMin+mice through NF-κB signaling pathway of dendritic cells.Conclusion:1 Fn AI-2 and stress alter the structure of mice gut microbiome.2 Fn AI-2 may promote the formation of intestinal tumors in C57BL/6-ApcMin/+mice through NF-κB signaling pathway of dendritic cells.3 Stress may promote the formation of Fn-related intestinal tumors in C57BL/6-ApcMin/+ mice through dopamine,norepinephrine.