Although the aetiology of inflammatory bowel disease (IBD) remains unknown, the pathogenesis is gradually being unravelled, seeming to be the result of a combination of environmental, genetic, and immunological factor...Although the aetiology of inflammatory bowel disease (IBD) remains unknown, the pathogenesis is gradually being unravelled, seeming to be the result of a combination of environmental, genetic, and immunological factors in which an uncontrolled immune response within the intestinal lumen leads to inflammation in genetically predisposed individuals. Multifactorial evidence suggests that a defect of innate immune response to microbial agents is involved in IBD. This editorial outlines the immunopathogenesis of IBD and their current and future therapy. We present IBD as a result of dysregulated mucosal response in the intestinal wall facilitated by defects in epithelial barrier function and the mucosal immune system with excessive production of cytokines growth factors, adhesion molecules, and reactive oxygen metabolites, resulting in tissue injury. Established and evolving therapies are discussed in the second part of this editorial and at the end of this section we review new therapies to modulate the immune system in patients with IBD.展开更多
AIM: To further assess of the incidence and localization of Crohn's disease (CD) in a well-defined population during the 1990s and to evaluate the prevalence of CD on the 1^st of January 2002. METHODS: In a retro...AIM: To further assess of the incidence and localization of Crohn's disease (CD) in a well-defined population during the 1990s and to evaluate the prevalence of CD on the 1^st of January 2002. METHODS: In a retrospective population based study, all 16-90 years old citizens of Stockholm County diagnosed as having CD according to Lennard Jones' criteria between 1990 and 2001 were included. Case identification was made by using computerized inpatient and outpatient registers. Moreover private gastroenterologists were asked for possible cases. The extent of the disease and the frequency of anorectal fistulae were determined as were the ages at diagnosis. Further, the prevalence of CD on the 1^st of January 2002 was assessed. RESULTS: All the 1 389 patients, 689 men and 700 women, fulfilled the criteria for CD. The mean incidence rate for the whole period was 8.3 per 10s (95%CI 7.9 -8.8). There was no difference between the genders. The mean annual incidence of the whole study period for colorectal disease and ileocecal disease, was 4.4 (95%CI 4.0-4.7) and 2.4 (95%CI 2.1-2.6) per 10s, respectively. Perianal disease occurred in 13.7% (95%CI 11.9-15.7 %) of the patients. The prevalence of CD was 213 per 100 000 inhabitants. CONCLUSION: The incidence of CD has markedly increased during the last decade in Stockholm County and 0.2% of the population suffers from CD. The increase is attributed to a further increase of colorectal disease, while the incidence of ileocecal disease has remained stable.展开更多
Inflammatory bowel disease (IBD) arises from disruption of immune tolerance to the gut commensal microbiota, leading to chronic intestinal inflammation and mucosal damage in genetically predisposed hosts. In healthy...Inflammatory bowel disease (IBD) arises from disruption of immune tolerance to the gut commensal microbiota, leading to chronic intestinal inflammation and mucosal damage in genetically predisposed hosts. In healthy individuals the intestinal microbiota have a symbiotic relationship with the host organism and possess important and unique functions, including a metabolic function (i.e. digestion of dietary compounds and xenobiotics, fermentation of undigestible carbohydrates with production of short chain fatty acids), a mucosal barrier function (i.e. by inhibiting pathogen invasion and strengthening epithelial barrier integrity), and an immune modula- tory function (i.e. mucosal immune system priming and maintenance of intestinal epithelium homeostasis). A fine balance regulates the mechanism that allows co- existence of mammals with their commensal bacteria. In IBD this mechanism of immune tolerance is impaired because of several potential causative factors. The gut microbiota composition and activity of IBD patients are abnormal, with a decreased prevalence of dominant members of the human commensal microbiota (i.e. Clostridium IXa and IV groups, Bacteroides, bifldobacteria) and a concomitant increase in detrimental bacteria (i.e. sulphate-reducing bacteria, Escherichia coll. The observed dysbiosis is concomitant with defectiveinnate immunity and bacterial killing (i.e. reduced mucosal defensins and IgA, malfunctioning phagocytosis) and overaggressive adaptive immune response (due to ineffective regulatory T cells and antigen presenting cells), which are considered the basis of IBD pathogen- esis. However, we still do not know how the interplay between these parameters causes the disease. Studies looking at gut microbial composition, epithelial integrity and mucosal immune markers in genotyped IBD populations are therefore warranted to shed light on this obscure pathogenesis.展开更多
Crohn's disease and ulcerative colitis are chronic relapsing immune mediated disorders that results from an aberrant response to gut luminal antigen in genetically susceptible host. The adaptive immune response that ...Crohn's disease and ulcerative colitis are chronic relapsing immune mediated disorders that results from an aberrant response to gut luminal antigen in genetically susceptible host. The adaptive immune response that is then triggered was widely considered to be a T-helper-1 mediated condition in Crohn's disease and T-helpero2 mediated condition in ulcerative colitis. Recent studies in animal models, genome wide association, and basic science has provided important insights in in the immunopathogenesis of inflammatory bowel disease, one of which was the characterization of the interleukin-23/Th-17 axis.展开更多
Over the past four years, the field of the innate immune response has been highly influenced by the discovery of the IKB kinase (IKK)-related kinases, TANK Binding Kinase I (TBK1) and IKKi, which regulate the acti...Over the past four years, the field of the innate immune response has been highly influenced by the discovery of the IKB kinase (IKK)-related kinases, TANK Binding Kinase I (TBK1) and IKKi, which regulate the activity of interferon regulatory factor (IRF)-3/IRF-7 and NF-κB transcription factors. More recently, additional essential components of the signaling pathways that activate these IKK homologues have been discovered. These include the RNA helicases RIGi and MDA5, and the downstream mitochondrial effector known as CARDIF/MAVS/VISA/IPS-1. In addition to their essential functions in controlling the innate immune response, recent studies have highlighted a role of these kinases in cell proliferation and oncogenesis. The canonical IKKs are well recognized to be a bridge linking chronic inflammation to cancer. New findings now suggest that the IKK-related kinases TBK1 and IKKi also participate in signaling pathways that impact on cell transformation and tumor progression. This review will therefore summarize and discuss the role of TBK1 and IKKi in cellular transformation and oncogenesis by focusing on their regulation and substrate specificity.展开更多
AIM:Many defense factors of the mother's colostrum or milk protect infants from intestinal, respiratory and systemic infections. In the present study, we investigated the effect of colostrum and mature human milk ...AIM:Many defense factors of the mother's colostrum or milk protect infants from intestinal, respiratory and systemic infections. In the present study, we investigated the effect of colostrum and mature human milk on E. histolytica parasites in vitro.METHODS:Samples of human milk were collected from 5 healthy lactating mothers.The medium with human milk at concentrations of 2%, 5% and 10% was obtained.RESULTS:The lethal effect of E. histolytica on the medium supplemented with different concentrations of both colostrum and mature human milk was significant during the first 30min. We also detected that the results of colostrum and mature human milk were similar. No statistically significant differences were found between same concentrations of colostrum and mature human milk at the same times.CONCLUSION:Colostrum and mature human milk have significant lethal effect on E. histolytica and protect against its infection in breast fed children.展开更多
Inflammatory bowel diseases(IBD) are a complex group of diseases involving alterations in mucosal immunity and gastrointestinal physiology during both initiation and progressive phases of the disease.At the core of th...Inflammatory bowel diseases(IBD) are a complex group of diseases involving alterations in mucosal immunity and gastrointestinal physiology during both initiation and progressive phases of the disease.At the core of these alterations are endothelial cells,whose continual adjustments in structure and function coordinate vascular supply,immune cell emigration,and regulation of the tissue environment.Expansion of the endothelium in IBD(angiogenesis),mediated by inflammatory growth factors,cytokines and chemokines,is a hallmark of active gut disease and is closely related to disease severity.The endothelium in newly formed or inflamed vessels differs from that in normal vessels in the production of and response to inflammatory cytokines,growth factors,and adhesion molecules,altering coagulant capacity,barrier function and blood cell recruitment in injury.This review examines the roles of the endothelium in the initiation and propagation of IBD pathology and distinctive features of the intestinal endothelium contributing to these conditions.展开更多
Inflammatory bowel disease(IBD)is a common and lifelong disabling gastrointestinal disease.Emerging treatments are being developed to target inflammatory cytokines which initiate and perpetuate the immune response.Ade...Inflammatory bowel disease(IBD)is a common and lifelong disabling gastrointestinal disease.Emerging treatments are being developed to target inflammatory cytokines which initiate and perpetuate the immune response.Adenosine is an important modulator of inflammation and its anti-inflammatory effects have been well established in humans as well as in animal models.High extracellular adenosine suppresses and resolves chronic inflammation in IBD models.High extracellular adenosine levels could be achieved by enhanced adenosine absorption and increased de novo synthesis.Increased adenosine concentration leads to activation of the A2a receptor on the cell surface of immune and epithelial cells that would be a potential therapeutic target for chronic intestinal inflammation. Adenosine is transported via concentrative nucleoside transporter and equilibrative nucleoside transporter transporters that are localized in apical and basolateral membranes of intestinal epithelial cells,respectively. Increased extracellular adenosine levels activate the A2a receptor,which would reduce cytokines responsible for chronic inflammation.展开更多
Inflammatory bowel diseases are the consequence of a dysregulated mucosal immune system. The mucosal immune system consists of two arms, innate and adaptive immunity, that have been studied separately for a long time....Inflammatory bowel diseases are the consequence of a dysregulated mucosal immune system. The mucosal immune system consists of two arms, innate and adaptive immunity, that have been studied separately for a long time. Functional studies from in vivo models of intestinal inflammation as well as results from genome-wide association studies strongly suggest a crossregulation of both arms. The present review will illustrate this interaction by selecting examples from innate immunity and adaptive immunity, and their direct impact on each other. Broadening our view by focusing on the cross-regulated areas of the mucosal immune system will not only facilitate our understanding of disease, but furthermore will allow identification of future therapeutic targets.展开更多
AIM: TO explore the relationship among interferon-γ (IFN-γ) activity, fibrogenesis, T cell immune responses and hepatic inflammatory activity. METHODS: Peripheral blood samples from a total of 43 hepatitis B cir...AIM: TO explore the relationship among interferon-γ (IFN-γ) activity, fibrogenesis, T cell immune responses and hepatic inflammatory activity. METHODS: Peripheral blood samples from a total of 43 hepatitis B cirrhotic patients (LC) and 19 healthy controls (NC) were collected to measure their serum levels of IFN-γ, interleukin-2 (IL-2), soluble interleukin-2 receptor (sIL-2R), interleukin-10 (IL-10) and three serological markers of fibrosis including hyaluronic acid (HA), procollagen type III peptide (PIIIP), and type iV collagen were measured using a double antibody sandwich ELISA. Also, serum total bilirubin (TB) and alanine aminotransferase (ALT) were measured by routine measures. RESULTS: The concentrations of serological markers of fibrosis in patients with active cirrhosis (ALC) were significantly higher than those in stationary liver cirrhosis (SLC) or NC groups. The levels of serological markers in HBeAg-positive patients were significantly higher than those in HBeAg-negative patients. In SLC and ALC patients, a negative linear correlation was found between IFN-γ levels and the serological markers of fibrosis. IFN-γ and IL-2 levels in the ALC group were significantly higher than those in the SLC and NC groups, but the statistical difference was not significant between the latter two. In contrast, IL-10 levels in the SLC group were significantly higher than that in the NC group, but no significant difference was found between SLC and ALC groups. The sIL-2R level was elevated gradually in all these groups, and the differences were significant. Positive linear correlations were seen between IFN-γ activity and ALT levels (r = 0.339, P 〈 0.05), and IL-2 activity and TB levels (r = 0.517, P 〈 0.05). sIL-2R expression was positively correlated with both ALT and TB levels (r = 0.324, 0.455, P 〈 0.05), whereas there was no statistically significant correlation between IL-10 expression and serum ALT and TB levels (r = -0.102, -0.093, P 〉 0.05). Finally, there was a positive correlation between IFN-γ and IL-2 levels. CONCLUSION: T cell immune responses are correlated with fibrosis and hepatic inflammatory activity and may play an important role in liver cirrhosis.展开更多
Cytokines are indispensable signals of the mucosaassociated immune system for maintaining normal gut homeostasis.An imbalance of their profile in favour of inflammation initiation may lead to disease states,such as th...Cytokines are indispensable signals of the mucosaassociated immune system for maintaining normal gut homeostasis.An imbalance of their profile in favour of inflammation initiation may lead to disease states,such as that is observed in inflammatory bowel diseases(IBD).Although Crohn's disease(CD) is often described as a prototype of T-helper 1-type diseases,and ulcerative colitis(UC) is traditionally viewed as a T-helper 2-mediated condition,the classic paradigm,which categorises cytokines into pro-and anti-inflammatory groups,has recently been changed.The inflammation regulatory pathways may not be mutually exclusive as individual cytokines can have diverse and even opposing functions in various clinical and immunological settings.None the less there are many common immunological responses in IBD that are mediated by cytokines.Although they regulate and influence the development,course and recurrence of the inflammatory process,the concrete pathogenic role of these small signaling molecules is sometimes not unambiguous in the subtypes of the disease.Our aim is to review the current information about pro-and anti-inflammatory effects of traditionally studied and recently discovered cytokines in the pathogenesis of UC and CD.The better understanding of their production and functional activity may lead to the development of new therapeutic modalities.展开更多
Helicobacter pylori(H pylori) infection is a leading world-wide infectious disease as it affects more than half of the world population and causes chronic gastritis,peptic ulcer disease and gastric malignancies.The in...Helicobacter pylori(H pylori) infection is a leading world-wide infectious disease as it affects more than half of the world population and causes chronic gastritis,peptic ulcer disease and gastric malignancies.The infection elicits a chronic cellular inflammatory response in the gastric mucosa.However,the effects of this local inflammation may not be confi ned solely to the digestive tract but may spread to involve extraintestinal tissues and/or organs.Indeed,H pylori infection has been epidemiologically linked to extra-digestive conditions and diseases.In this context,it has been speculated that H pylori infection may be responsible for various endocrine disorders,such as autoimmune thyroid diseases,diabetes mellitus,dyslipidemia,obesity,osteoporosis and primary hyperparathyroidism.This is a review of the relationship between H pylori infection and these endocrine disorders.展开更多
AIM:To investigate whether butyrate or glutamine enemas could diminish inflammation in experimental diversion colitis.METHODS:Wistar specific pathogen-free rats were submitted to a Hartmann's end colostomy and tre...AIM:To investigate whether butyrate or glutamine enemas could diminish inflammation in experimental diversion colitis.METHODS:Wistar specific pathogen-free rats were submitted to a Hartmann's end colostomy and treated with enemas containing glutamine,butyrate,or saline.Enemas were administered twice a week in the excluded segment of the colon from 4 to 12 wk after the surgical procedure.Follow-up colonoscopy was performed every 4 wk for 12 wk.The effect of treatment was evaluated using video-endoscopic and histologic scores and measuring interleukin-1β,tumor necrosis factor-alpha,and transforming growth factor beta production in organ cultures by enzyme linked immunosorbent assay.RESULTS:Colonoscopies of the diverted segment showed mucosa with hyperemia,increased number of vessels,bleeding and mucus discharge.Treatment with either glutamine or butyrate induced significant reductions in both colonoscopic(P < 0.02) and histological scores(P < 0.01) and restored the densities of collagen fibers in tissue(P = 0.015;P = 0.001),the number of goblet cells(P = 0.021;P = 0.029),and the rate of apoptosis within the epithelium(P = 0.043;P = 0.011) to normal values.The high levels of cytokines in colon explants from rats with diversion colitis significantly decreased to normal values after treatment with butyrate or glutamine.CONCLUSION:The improvement of experimental diversion colitis following glutamine or butyrate enemas highlights the importance of specific luminal nutrients in the homeostasis of the colonic mucosa and supports their utilization for the treatment of human diversion colitis.展开更多
Patients with extensive or complicated Crohn's disease(CD) at diagnosis should be treated straightaway with immunosuppressive therapy according to the most recent guidelines.In patients with localized and uncompli...Patients with extensive or complicated Crohn's disease(CD) at diagnosis should be treated straightaway with immunosuppressive therapy according to the most recent guidelines.In patients with localized and uncomplicated CD at diagnosis,early use of immunosuppressive therapy is debated for preventing disease progression and limiting the disabling clinical impact.In this context,there is a need for predictors of benign or unfavourable subsequent clinical course,in order to avoid over-treating with risky drugs those patients who would have experienced spontaneous mid-term asymptomatic disease without progression towards irreversible intestinal lesions.At diagnosis,an age below 40 years,the presence of perianal lesions and the need for treating the first flare with steroids have been consistently associated with an unfavourable subsequent 5-year or 10-year clinical course.The positive predictive value of unfavourable course in patients with 2 or 3 predictors ranges between 0.75 and 0.95 in population-based and referral centre cohorts.Consequently,the use of these predictors can be integrated into the elements that influence individual decisions.In the CD postoperative context,keeping smoking and history of prior resection are the stron-gest predictors of disease symptomatic recurrence.However,these clinical predictors alone are not as reliable as severity of early postoperative endoscopic recurrence in clinical practice.In ulcerative colitis(UC),extensive colitis at diagnosis is associated with unfavourable clinical course in the first 5 to 10 years of the disease,and also with long-term colectomy and colorectal inflammation-associated colorectal cancer.In patients with extensive UC at diagnosis,a rapid step-up strategy aiming to achieve sustained deep remission should therefore be considered.At the moment,no reliable serological or genetic predictor of inflammatory bowel disease clinical course has been identified.展开更多
文摘Although the aetiology of inflammatory bowel disease (IBD) remains unknown, the pathogenesis is gradually being unravelled, seeming to be the result of a combination of environmental, genetic, and immunological factors in which an uncontrolled immune response within the intestinal lumen leads to inflammation in genetically predisposed individuals. Multifactorial evidence suggests that a defect of innate immune response to microbial agents is involved in IBD. This editorial outlines the immunopathogenesis of IBD and their current and future therapy. We present IBD as a result of dysregulated mucosal response in the intestinal wall facilitated by defects in epithelial barrier function and the mucosal immune system with excessive production of cytokines growth factors, adhesion molecules, and reactive oxygen metabolites, resulting in tissue injury. Established and evolving therapies are discussed in the second part of this editorial and at the end of this section we review new therapies to modulate the immune system in patients with IBD.
基金Supported by the grants from Knut and Alice Wallenbergs foundation
文摘AIM: To further assess of the incidence and localization of Crohn's disease (CD) in a well-defined population during the 1990s and to evaluate the prevalence of CD on the 1^st of January 2002. METHODS: In a retrospective population based study, all 16-90 years old citizens of Stockholm County diagnosed as having CD according to Lennard Jones' criteria between 1990 and 2001 were included. Case identification was made by using computerized inpatient and outpatient registers. Moreover private gastroenterologists were asked for possible cases. The extent of the disease and the frequency of anorectal fistulae were determined as were the ages at diagnosis. Further, the prevalence of CD on the 1^st of January 2002 was assessed. RESULTS: All the 1 389 patients, 689 men and 700 women, fulfilled the criteria for CD. The mean incidence rate for the whole period was 8.3 per 10s (95%CI 7.9 -8.8). There was no difference between the genders. The mean annual incidence of the whole study period for colorectal disease and ileocecal disease, was 4.4 (95%CI 4.0-4.7) and 2.4 (95%CI 2.1-2.6) per 10s, respectively. Perianal disease occurred in 13.7% (95%CI 11.9-15.7 %) of the patients. The prevalence of CD was 213 per 100 000 inhabitants. CONCLUSION: The incidence of CD has markedly increased during the last decade in Stockholm County and 0.2% of the population suffers from CD. The increase is attributed to a further increase of colorectal disease, while the incidence of ileocecal disease has remained stable.
文摘Inflammatory bowel disease (IBD) arises from disruption of immune tolerance to the gut commensal microbiota, leading to chronic intestinal inflammation and mucosal damage in genetically predisposed hosts. In healthy individuals the intestinal microbiota have a symbiotic relationship with the host organism and possess important and unique functions, including a metabolic function (i.e. digestion of dietary compounds and xenobiotics, fermentation of undigestible carbohydrates with production of short chain fatty acids), a mucosal barrier function (i.e. by inhibiting pathogen invasion and strengthening epithelial barrier integrity), and an immune modula- tory function (i.e. mucosal immune system priming and maintenance of intestinal epithelium homeostasis). A fine balance regulates the mechanism that allows co- existence of mammals with their commensal bacteria. In IBD this mechanism of immune tolerance is impaired because of several potential causative factors. The gut microbiota composition and activity of IBD patients are abnormal, with a decreased prevalence of dominant members of the human commensal microbiota (i.e. Clostridium IXa and IV groups, Bacteroides, bifldobacteria) and a concomitant increase in detrimental bacteria (i.e. sulphate-reducing bacteria, Escherichia coll. The observed dysbiosis is concomitant with defectiveinnate immunity and bacterial killing (i.e. reduced mucosal defensins and IgA, malfunctioning phagocytosis) and overaggressive adaptive immune response (due to ineffective regulatory T cells and antigen presenting cells), which are considered the basis of IBD pathogen- esis. However, we still do not know how the interplay between these parameters causes the disease. Studies looking at gut microbial composition, epithelial integrity and mucosal immune markers in genotyped IBD populations are therefore warranted to shed light on this obscure pathogenesis.
文摘Crohn's disease and ulcerative colitis are chronic relapsing immune mediated disorders that results from an aberrant response to gut luminal antigen in genetically susceptible host. The adaptive immune response that is then triggered was widely considered to be a T-helper-1 mediated condition in Crohn's disease and T-helpero2 mediated condition in ulcerative colitis. Recent studies in animal models, genome wide association, and basic science has provided important insights in in the immunopathogenesis of inflammatory bowel disease, one of which was the characterization of the interleukin-23/Th-17 axis.
文摘Over the past four years, the field of the innate immune response has been highly influenced by the discovery of the IKB kinase (IKK)-related kinases, TANK Binding Kinase I (TBK1) and IKKi, which regulate the activity of interferon regulatory factor (IRF)-3/IRF-7 and NF-κB transcription factors. More recently, additional essential components of the signaling pathways that activate these IKK homologues have been discovered. These include the RNA helicases RIGi and MDA5, and the downstream mitochondrial effector known as CARDIF/MAVS/VISA/IPS-1. In addition to their essential functions in controlling the innate immune response, recent studies have highlighted a role of these kinases in cell proliferation and oncogenesis. The canonical IKKs are well recognized to be a bridge linking chronic inflammation to cancer. New findings now suggest that the IKK-related kinases TBK1 and IKKi also participate in signaling pathways that impact on cell transformation and tumor progression. This review will therefore summarize and discuss the role of TBK1 and IKKi in cellular transformation and oncogenesis by focusing on their regulation and substrate specificity.
文摘AIM:Many defense factors of the mother's colostrum or milk protect infants from intestinal, respiratory and systemic infections. In the present study, we investigated the effect of colostrum and mature human milk on E. histolytica parasites in vitro.METHODS:Samples of human milk were collected from 5 healthy lactating mothers.The medium with human milk at concentrations of 2%, 5% and 10% was obtained.RESULTS:The lethal effect of E. histolytica on the medium supplemented with different concentrations of both colostrum and mature human milk was significant during the first 30min. We also detected that the results of colostrum and mature human milk were similar. No statistically significant differences were found between same concentrations of colostrum and mature human milk at the same times.CONCLUSION:Colostrum and mature human milk have significant lethal effect on E. histolytica and protect against its infection in breast fed children.
基金Supported by National Institute of Health,NIH DK 43785
文摘Inflammatory bowel diseases(IBD) are a complex group of diseases involving alterations in mucosal immunity and gastrointestinal physiology during both initiation and progressive phases of the disease.At the core of these alterations are endothelial cells,whose continual adjustments in structure and function coordinate vascular supply,immune cell emigration,and regulation of the tissue environment.Expansion of the endothelium in IBD(angiogenesis),mediated by inflammatory growth factors,cytokines and chemokines,is a hallmark of active gut disease and is closely related to disease severity.The endothelium in newly formed or inflamed vessels differs from that in normal vessels in the production of and response to inflammatory cytokines,growth factors,and adhesion molecules,altering coagulant capacity,barrier function and blood cell recruitment in injury.This review examines the roles of the endothelium in the initiation and propagation of IBD pathology and distinctive features of the intestinal endothelium contributing to these conditions.
基金Supported by A research grant(DK-018777)from the National Institute of Diabetes and Digestive and Kidney Diseases
文摘Inflammatory bowel disease(IBD)is a common and lifelong disabling gastrointestinal disease.Emerging treatments are being developed to target inflammatory cytokines which initiate and perpetuate the immune response.Adenosine is an important modulator of inflammation and its anti-inflammatory effects have been well established in humans as well as in animal models.High extracellular adenosine suppresses and resolves chronic inflammation in IBD models.High extracellular adenosine levels could be achieved by enhanced adenosine absorption and increased de novo synthesis.Increased adenosine concentration leads to activation of the A2a receptor on the cell surface of immune and epithelial cells that would be a potential therapeutic target for chronic intestinal inflammation. Adenosine is transported via concentrative nucleoside transporter and equilibrative nucleoside transporter transporters that are localized in apical and basolateral membranes of intestinal epithelial cells,respectively. Increased extracellular adenosine levels activate the A2a receptor,which would reduce cytokines responsible for chronic inflammation.
基金Supported by SFB 633 of the Deutsche Forschungsgemeinschaft
文摘Inflammatory bowel diseases are the consequence of a dysregulated mucosal immune system. The mucosal immune system consists of two arms, innate and adaptive immunity, that have been studied separately for a long time. Functional studies from in vivo models of intestinal inflammation as well as results from genome-wide association studies strongly suggest a crossregulation of both arms. The present review will illustrate this interaction by selecting examples from innate immunity and adaptive immunity, and their direct impact on each other. Broadening our view by focusing on the cross-regulated areas of the mucosal immune system will not only facilitate our understanding of disease, but furthermore will allow identification of future therapeutic targets.
基金Supported by Shanghai Leading Academic Discipline Project,No. Y0205
文摘AIM: TO explore the relationship among interferon-γ (IFN-γ) activity, fibrogenesis, T cell immune responses and hepatic inflammatory activity. METHODS: Peripheral blood samples from a total of 43 hepatitis B cirrhotic patients (LC) and 19 healthy controls (NC) were collected to measure their serum levels of IFN-γ, interleukin-2 (IL-2), soluble interleukin-2 receptor (sIL-2R), interleukin-10 (IL-10) and three serological markers of fibrosis including hyaluronic acid (HA), procollagen type III peptide (PIIIP), and type iV collagen were measured using a double antibody sandwich ELISA. Also, serum total bilirubin (TB) and alanine aminotransferase (ALT) were measured by routine measures. RESULTS: The concentrations of serological markers of fibrosis in patients with active cirrhosis (ALC) were significantly higher than those in stationary liver cirrhosis (SLC) or NC groups. The levels of serological markers in HBeAg-positive patients were significantly higher than those in HBeAg-negative patients. In SLC and ALC patients, a negative linear correlation was found between IFN-γ levels and the serological markers of fibrosis. IFN-γ and IL-2 levels in the ALC group were significantly higher than those in the SLC and NC groups, but the statistical difference was not significant between the latter two. In contrast, IL-10 levels in the SLC group were significantly higher than that in the NC group, but no significant difference was found between SLC and ALC groups. The sIL-2R level was elevated gradually in all these groups, and the differences were significant. Positive linear correlations were seen between IFN-γ activity and ALT levels (r = 0.339, P 〈 0.05), and IL-2 activity and TB levels (r = 0.517, P 〈 0.05). sIL-2R expression was positively correlated with both ALT and TB levels (r = 0.324, 0.455, P 〈 0.05), whereas there was no statistically significant correlation between IL-10 expression and serum ALT and TB levels (r = -0.102, -0.093, P 〉 0.05). Finally, there was a positive correlation between IFN-γ and IL-2 levels. CONCLUSION: T cell immune responses are correlated with fibrosis and hepatic inflammatory activity and may play an important role in liver cirrhosis.
文摘Cytokines are indispensable signals of the mucosaassociated immune system for maintaining normal gut homeostasis.An imbalance of their profile in favour of inflammation initiation may lead to disease states,such as that is observed in inflammatory bowel diseases(IBD).Although Crohn's disease(CD) is often described as a prototype of T-helper 1-type diseases,and ulcerative colitis(UC) is traditionally viewed as a T-helper 2-mediated condition,the classic paradigm,which categorises cytokines into pro-and anti-inflammatory groups,has recently been changed.The inflammation regulatory pathways may not be mutually exclusive as individual cytokines can have diverse and even opposing functions in various clinical and immunological settings.None the less there are many common immunological responses in IBD that are mediated by cytokines.Although they regulate and influence the development,course and recurrence of the inflammatory process,the concrete pathogenic role of these small signaling molecules is sometimes not unambiguous in the subtypes of the disease.Our aim is to review the current information about pro-and anti-inflammatory effects of traditionally studied and recently discovered cytokines in the pathogenesis of UC and CD.The better understanding of their production and functional activity may lead to the development of new therapeutic modalities.
文摘Helicobacter pylori(H pylori) infection is a leading world-wide infectious disease as it affects more than half of the world population and causes chronic gastritis,peptic ulcer disease and gastric malignancies.The infection elicits a chronic cellular inflammatory response in the gastric mucosa.However,the effects of this local inflammation may not be confi ned solely to the digestive tract but may spread to involve extraintestinal tissues and/or organs.Indeed,H pylori infection has been epidemiologically linked to extra-digestive conditions and diseases.In this context,it has been speculated that H pylori infection may be responsible for various endocrine disorders,such as autoimmune thyroid diseases,diabetes mellitus,dyslipidemia,obesity,osteoporosis and primary hyperparathyroidism.This is a review of the relationship between H pylori infection and these endocrine disorders.
基金Supported by Grants from the Brazilian Research CouncilFundao de Amparo à Pesquisa do Estado do Rio de Janeiro
文摘AIM:To investigate whether butyrate or glutamine enemas could diminish inflammation in experimental diversion colitis.METHODS:Wistar specific pathogen-free rats were submitted to a Hartmann's end colostomy and treated with enemas containing glutamine,butyrate,or saline.Enemas were administered twice a week in the excluded segment of the colon from 4 to 12 wk after the surgical procedure.Follow-up colonoscopy was performed every 4 wk for 12 wk.The effect of treatment was evaluated using video-endoscopic and histologic scores and measuring interleukin-1β,tumor necrosis factor-alpha,and transforming growth factor beta production in organ cultures by enzyme linked immunosorbent assay.RESULTS:Colonoscopies of the diverted segment showed mucosa with hyperemia,increased number of vessels,bleeding and mucus discharge.Treatment with either glutamine or butyrate induced significant reductions in both colonoscopic(P < 0.02) and histological scores(P < 0.01) and restored the densities of collagen fibers in tissue(P = 0.015;P = 0.001),the number of goblet cells(P = 0.021;P = 0.029),and the rate of apoptosis within the epithelium(P = 0.043;P = 0.011) to normal values.The high levels of cytokines in colon explants from rats with diversion colitis significantly decreased to normal values after treatment with butyrate or glutamine.CONCLUSION:The improvement of experimental diversion colitis following glutamine or butyrate enemas highlights the importance of specific luminal nutrients in the homeostasis of the colonic mucosa and supports their utilization for the treatment of human diversion colitis.
文摘Patients with extensive or complicated Crohn's disease(CD) at diagnosis should be treated straightaway with immunosuppressive therapy according to the most recent guidelines.In patients with localized and uncomplicated CD at diagnosis,early use of immunosuppressive therapy is debated for preventing disease progression and limiting the disabling clinical impact.In this context,there is a need for predictors of benign or unfavourable subsequent clinical course,in order to avoid over-treating with risky drugs those patients who would have experienced spontaneous mid-term asymptomatic disease without progression towards irreversible intestinal lesions.At diagnosis,an age below 40 years,the presence of perianal lesions and the need for treating the first flare with steroids have been consistently associated with an unfavourable subsequent 5-year or 10-year clinical course.The positive predictive value of unfavourable course in patients with 2 or 3 predictors ranges between 0.75 and 0.95 in population-based and referral centre cohorts.Consequently,the use of these predictors can be integrated into the elements that influence individual decisions.In the CD postoperative context,keeping smoking and history of prior resection are the stron-gest predictors of disease symptomatic recurrence.However,these clinical predictors alone are not as reliable as severity of early postoperative endoscopic recurrence in clinical practice.In ulcerative colitis(UC),extensive colitis at diagnosis is associated with unfavourable clinical course in the first 5 to 10 years of the disease,and also with long-term colectomy and colorectal inflammation-associated colorectal cancer.In patients with extensive UC at diagnosis,a rapid step-up strategy aiming to achieve sustained deep remission should therefore be considered.At the moment,no reliable serological or genetic predictor of inflammatory bowel disease clinical course has been identified.