BACKGROUND The dysbiosis of the gut microbiome is evident in Crohn's disease(CD) compared with healthy controls(HC), although the alterations from active CD to remission after treatment are unclear.AIM To characte...BACKGROUND The dysbiosis of the gut microbiome is evident in Crohn's disease(CD) compared with healthy controls(HC), although the alterations from active CD to remission after treatment are unclear.AIM To characterize the mucosa-associated gut microbiota in patients with CD before and after the induction therapy.METHODS The basic information was collected from the subjects and the CD activity index(CDAI) was calculated in patients. A 16S rRNA sequencing approach was applied to determine the structures of microbial communities in mucosal samples including the terminal ileal, ascending colon, descending colon and rectum. The composition and function of mucosa-associated gut microbiota were compared between samples from the same cohort of patients before and after treatment.Differential taxa were identified to calculate the microbial dysbiosis index(MDI)and the correlation between MDI and CDAI was analyzed using Pearson correlation test. Predictive functional profiling of microbial communities was obtained with PICRUSt.RESULTS There were no significant differences in microbial richness among the four anatomical sites in individuals. Compared to active disease, the alpha diversity of CD in remission was increased towards the level of HC compared to the active stage. The principal coordinate analysis revealed that samples of active CD were clearly separated from those in remission, which clustered close to HC. Sixty-five genera were identified as differentially abundant between active and quiescent CD, with a loss of Fusobacterium and a gain of potential beneficial bacteria including Lactobacillus, Akkermansia, Roseburia, Ruminococcus and Lachnospira after the induction of remission. The combination of these taxa into a MDI showed a positive correlation with clinical disease severity and a negative correlation with species richness. The increased capacity for the inferred pathways including Lipopolysaccharide biosynthesis and Lipopolysaccharide biosynthesis proteins in patients before treatment negatively correlated with the abundance of Roseburia,Ruminococcus and Lachnospira.CONCLUSION The dysbiosis of mucosa-associated microbiota was associated with the disease phenotype and may become a potential diagnostic tool for the recurrence of disease.展开更多
As the gastrointestinal tract may also be a crucial entry or interaction site of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the role of the gut mucosal immune system as a first-line physical and immun...As the gastrointestinal tract may also be a crucial entry or interaction site of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the role of the gut mucosal immune system as a first-line physical and immunological defense is critical.Furthermore,gastrointestinal involvement and symptoms in coronavirus disease 2019(COVID-19)patients have been linked to worse clinical outcomes.This review discusses recent data on the interactions between the virus and the immune cells and molecules in the mucosa during the infection.By carrying out appropriate investigations,the mucosal immune system role in SARS-CoV-2 infection in therapy and prevention can be established.In line with this,COVID-19 vaccines that stimulate mucosal immunity against the virus may have more advantages than the others.展开更多
The intestine and the gut-associated lymphoid tissue（GALT） are essential components of whole body immune defense,protecting the body from foreign antigens and pathogens,while allowing tolerance to commensal bacteria...The intestine and the gut-associated lymphoid tissue（GALT） are essential components of whole body immune defense,protecting the body from foreign antigens and pathogens,while allowing tolerance to commensal bacteria and dietary antigens.The requirement for protein to support the immune system is well established.Less is known regarding the immune modifying properties of individual amino acids,particularly on the GALT.Both oral and parenteral feeding studies have established convincing evidence that not only the total protein intake,but the availability of specific dietary amino acids（in particular glutamine,glutamate,and arginine,and perhaps methionine,cysteine and threonine） are essential to optimizing the immune functions of the intestine and the proximal resident immune cells.These amino acids each have unique properties that include,maintaining the integrity,growth and function of the intestine,as well as normalizing inflammatory cytokine secretion and improving T-lymphocyte numbers,specific T cell functions,and the secretion of IgA by lamina propria cells.Our understanding of this area has come from studies that have supplemented single amino acids to a mixed protein diet and measuring the effect on specific immune parameters.Future studies should be designed using amino acid mixtures that target a number of specific functions of GALT in order to optimize immune function in domestic animals and humans during critical periods of development and various disease states.展开更多
基金the National Natural Science Foundation of China,No.81660101 and No.81860106the Special Scientific Research Fund of Public Welfare Profession of National Health and Family Planning Commission,No.201502026the Graduate Innovation Fund of Nanchang University,No.CX2017251
文摘BACKGROUND The dysbiosis of the gut microbiome is evident in Crohn's disease(CD) compared with healthy controls(HC), although the alterations from active CD to remission after treatment are unclear.AIM To characterize the mucosa-associated gut microbiota in patients with CD before and after the induction therapy.METHODS The basic information was collected from the subjects and the CD activity index(CDAI) was calculated in patients. A 16S rRNA sequencing approach was applied to determine the structures of microbial communities in mucosal samples including the terminal ileal, ascending colon, descending colon and rectum. The composition and function of mucosa-associated gut microbiota were compared between samples from the same cohort of patients before and after treatment.Differential taxa were identified to calculate the microbial dysbiosis index(MDI)and the correlation between MDI and CDAI was analyzed using Pearson correlation test. Predictive functional profiling of microbial communities was obtained with PICRUSt.RESULTS There were no significant differences in microbial richness among the four anatomical sites in individuals. Compared to active disease, the alpha diversity of CD in remission was increased towards the level of HC compared to the active stage. The principal coordinate analysis revealed that samples of active CD were clearly separated from those in remission, which clustered close to HC. Sixty-five genera were identified as differentially abundant between active and quiescent CD, with a loss of Fusobacterium and a gain of potential beneficial bacteria including Lactobacillus, Akkermansia, Roseburia, Ruminococcus and Lachnospira after the induction of remission. The combination of these taxa into a MDI showed a positive correlation with clinical disease severity and a negative correlation with species richness. The increased capacity for the inferred pathways including Lipopolysaccharide biosynthesis and Lipopolysaccharide biosynthesis proteins in patients before treatment negatively correlated with the abundance of Roseburia,Ruminococcus and Lachnospira.CONCLUSION The dysbiosis of mucosa-associated microbiota was associated with the disease phenotype and may become a potential diagnostic tool for the recurrence of disease.
文摘As the gastrointestinal tract may also be a crucial entry or interaction site of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the role of the gut mucosal immune system as a first-line physical and immunological defense is critical.Furthermore,gastrointestinal involvement and symptoms in coronavirus disease 2019(COVID-19)patients have been linked to worse clinical outcomes.This review discusses recent data on the interactions between the virus and the immune cells and molecules in the mucosa during the infection.By carrying out appropriate investigations,the mucosal immune system role in SARS-CoV-2 infection in therapy and prevention can be established.In line with this,COVID-19 vaccines that stimulate mucosal immunity against the virus may have more advantages than the others.
基金supported by CJ Field’s funding from the Natural Sciences and Engineering Council of Canada (NSERC)
文摘The intestine and the gut-associated lymphoid tissue（GALT） are essential components of whole body immune defense,protecting the body from foreign antigens and pathogens,while allowing tolerance to commensal bacteria and dietary antigens.The requirement for protein to support the immune system is well established.Less is known regarding the immune modifying properties of individual amino acids,particularly on the GALT.Both oral and parenteral feeding studies have established convincing evidence that not only the total protein intake,but the availability of specific dietary amino acids（in particular glutamine,glutamate,and arginine,and perhaps methionine,cysteine and threonine） are essential to optimizing the immune functions of the intestine and the proximal resident immune cells.These amino acids each have unique properties that include,maintaining the integrity,growth and function of the intestine,as well as normalizing inflammatory cytokine secretion and improving T-lymphocyte numbers,specific T cell functions,and the secretion of IgA by lamina propria cells.Our understanding of this area has come from studies that have supplemented single amino acids to a mixed protein diet and measuring the effect on specific immune parameters.Future studies should be designed using amino acid mixtures that target a number of specific functions of GALT in order to optimize immune function in domestic animals and humans during critical periods of development and various disease states.
