In a recent study published in Cell,an in-depth study on the formation of nuclear stress bodies(nSBs)and their impact on gene expression has been reported.1 The system-wide role of nSBs has been a mystery so far,and t...In a recent study published in Cell,an in-depth study on the formation of nuclear stress bodies(nSBs)and their impact on gene expression has been reported.1 The system-wide role of nSBs has been a mystery so far,and the authors presented potential roles of nSBs in negatively regulating acute cytokine responses in inflammatory conditions and in protecting patients with sepsis.展开更多
A mounting body of evidence indicates that dietary fiber(DF)metabolites produced by commensal bacteria play essential roles in balancing the immune system.DF,considered nonessential nutrients in the past,is now consid...A mounting body of evidence indicates that dietary fiber(DF)metabolites produced by commensal bacteria play essential roles in balancing the immune system.DF,considered nonessential nutrients in the past,is now considered to be necessary to maintain adequate levels of immunity and suppress inflammatory and allergic responses.Short-chain fatty acids(SCFAs),such as acetate,propionate,and butyrate,are the major DF metabolites and mostly produced by specialized commensal bacteria that are capable of breaking down DF into simpler saccharides and further metabolizing the saccharides into SCFAs.SCFAs act on many cell types to regulate a number of important biological processes,including host metabolism,intestinal functions,and immunity system.This review specifically highlights the regulatory functions of DF and SCFAs in the immune system with a focus on major innate and adaptive lymphocytes.Current information regarding how SCFAs regulate innate lymphoid cells,T helper cells,cytotoxic T cells,and B cells and how these functions impact immunity,inflammation,and allergic responses are discussed.展开更多
Immune tolerance deletes or suppresses autoreactive lymphocytes and is established at multiple levels during the development,activation and effector phases of T and B cells.These mechanisms are cell-intrinsically prog...Immune tolerance deletes or suppresses autoreactive lymphocytes and is established at multiple levels during the development,activation and effector phases of T and B cells.These mechanisms are cell-intrinsically programmed and critical in preventing autoimmune diseases.We have witnessed the existence of another type of immune tolerance mechanism that is shaped by lifestyle choices,such as diet,microbiome and microbial metabolites.Short-chain fatty acids(SCFAs)are the most abundant microbial metabolites in the colonic lumen and are mainly produced by the microbial fermentation of prebiotics,such as dietary fiber.This review focuses on the preventive and immunomodulatory effects of SCFAs on autoimmunity.The tissue-and disease-specific effects of dietary fiber,SCFAs and SCFA-producing microbes on major types of autoimmune diseases,including type I diabetes,multiple sclerosis,rheumatoid arthritis and lupus,are discussed.Additionally,their key regulatory mechanisms for lymphocyte development,tissue barrier function,host metabolism,immunity,autoantibody production,and inflammatory effector and regulatory lymphocytes are discussed.The shared and differential effects of SCFAs on different types and stages of autoimmune diseases are discussed.展开更多
While both the spleen and lymph nodes are called secondary lymphoid tissues,how lymphocytes enter these tissues are quite different from each other.This is because the architecture of the two types of organs and the m...While both the spleen and lymph nodes are called secondary lymphoid tissues,how lymphocytes enter these tissues are quite different from each other.This is because the architecture of the two types of organs and the mode of lymphocyte migration into these organs are quite distinct.In the spleen,T cells are passively released in the blood flow from the arterioles in the red pulp and marginal zone area.In contrast,T cells in the blood are actively captured on high endothelial venules in lymph nodes by the coordinated actions of CCR7 and several adhesion molecules.A recent finding indicates that T cells,released in the red pulp and marginal zone areas,actively find their way to the white zone by utilizing the migration track created by periarteriolar stromal cells.This finding adds one more piece to our understanding of lymphocyte migration for effective adaptive immune responses in the spleen.展开更多
基金supported,in part,by the National Institute of Health(R01AI173179 to C.H.K.)the Rogel Cancer Center discovery award.C.H.K.is Kenneth and Judy Betz Professor of Food Allergy Research.
文摘In a recent study published in Cell,an in-depth study on the formation of nuclear stress bodies(nSBs)and their impact on gene expression has been reported.1 The system-wide role of nSBs has been a mystery so far,and the authors presented potential roles of nSBs in negatively regulating acute cytokine responses in inflammatory conditions and in protecting patients with sepsis.
基金supported,in part,by the NIH(R01AI121302,R21AI14889801,R01AI074745,and R01AI080769)Kenneth and Judy Betz Professorship at the Mary H.Weiser Food Allergy Center at the University of Michigan to C.H.K.
文摘A mounting body of evidence indicates that dietary fiber(DF)metabolites produced by commensal bacteria play essential roles in balancing the immune system.DF,considered nonessential nutrients in the past,is now considered to be necessary to maintain adequate levels of immunity and suppress inflammatory and allergic responses.Short-chain fatty acids(SCFAs),such as acetate,propionate,and butyrate,are the major DF metabolites and mostly produced by specialized commensal bacteria that are capable of breaking down DF into simpler saccharides and further metabolizing the saccharides into SCFAs.SCFAs act on many cell types to regulate a number of important biological processes,including host metabolism,intestinal functions,and immunity system.This review specifically highlights the regulatory functions of DF and SCFAs in the immune system with a focus on major innate and adaptive lymphocytes.Current information regarding how SCFAs regulate innate lymphoid cells,T helper cells,cytotoxic T cells,and B cells and how these functions impact immunity,inflammation,and allergic responses are discussed.
文摘Immune tolerance deletes or suppresses autoreactive lymphocytes and is established at multiple levels during the development,activation and effector phases of T and B cells.These mechanisms are cell-intrinsically programmed and critical in preventing autoimmune diseases.We have witnessed the existence of another type of immune tolerance mechanism that is shaped by lifestyle choices,such as diet,microbiome and microbial metabolites.Short-chain fatty acids(SCFAs)are the most abundant microbial metabolites in the colonic lumen and are mainly produced by the microbial fermentation of prebiotics,such as dietary fiber.This review focuses on the preventive and immunomodulatory effects of SCFAs on autoimmunity.The tissue-and disease-specific effects of dietary fiber,SCFAs and SCFA-producing microbes on major types of autoimmune diseases,including type I diabetes,multiple sclerosis,rheumatoid arthritis and lupus,are discussed.Additionally,their key regulatory mechanisms for lymphocyte development,tissue barrier function,host metabolism,immunity,autoantibody production,and inflammatory effector and regulatory lymphocytes are discussed.The shared and differential effects of SCFAs on different types and stages of autoimmune diseases are discussed.
基金supported in part by grants from the NIH(R01AI121302 and R21AI14889801).
文摘While both the spleen and lymph nodes are called secondary lymphoid tissues,how lymphocytes enter these tissues are quite different from each other.This is because the architecture of the two types of organs and the mode of lymphocyte migration into these organs are quite distinct.In the spleen,T cells are passively released in the blood flow from the arterioles in the red pulp and marginal zone area.In contrast,T cells in the blood are actively captured on high endothelial venules in lymph nodes by the coordinated actions of CCR7 and several adhesion molecules.A recent finding indicates that T cells,released in the red pulp and marginal zone areas,actively find their way to the white zone by utilizing the migration track created by periarteriolar stromal cells.This finding adds one more piece to our understanding of lymphocyte migration for effective adaptive immune responses in the spleen.
