ABSTRACT
Mucosal delivery of IL-27 has been shown to have a therapeutic benefit in murine models of inflammatory bowel disease (IBD). The IL-27 effect was associated with phosphorylated STAT1 (pSTAT1), a product of IL27 receptor signaling, in bowel tissue. To determine whether IL-27 acted directly on colonic epithelium, murine colonoids and primary intact colonic crypts were shown to be unresponsive to IL-27 in vitro and to lack detectable IL-27 receptors. On the other hand, macrophages, which are present in inflamed colon tissue, were responsive to IL-27 in vitro. IL-27 induced pSTAT1 in macrophages, the transcriptome indicated an IFN-like signature, and supernatants induced pSTAT1 in colonoids. IL-27 induced anti-viral activity in macrophages and MHC Class II induction. We conclude that the effects of mucosal delivery of IL-27 in murine IBD are in part based on the known effects of IL27 inducing immunosuppression of T cells mediated by IL-10. We also conclude that IL-27 has potent effects on macrophages in inflamed colon tissue, generating mediators that in turn act on colonic epithelium.
Subject(s)
Inflammatory Bowel Diseases , Interleukin-27 , Mice , Animals , Interleukin-27/therapeutic use , Colon , Inflammatory Bowel Diseases/drug therapy , Macrophages , EpitheliumABSTRACT
New treatment targets are needed for colorectal cancer (CRC). We define expression of High Mobility Group Box 1 (HMGB1) protein throughout colorectal neoplastic progression and examine the biological consequences of aberrant expression. HMGB1 is a ubiquitously expressed nuclear protein that shuttles to the cytoplasm under cellular stress. HMGB1 impacts cellular responses, acting as a cytokine when secreted. A total of 846 human tissue samples were retrieved; 6242 immunohistochemically stained sections were reviewed. Subcellular epithelial HMGB1 expression was assessed in a CRC Tissue Microarray (n = 650), normal colonic epithelium (n = 75), adenomatous polyps (n = 52), and CRC polyps (CaP, n = 69). Stromal lymphocyte phenotype was assessed in the CRC microarray and a subgroup of CaP. Normal colonic epithelium has strong nuclear and absent cytoplasmic HMGB1. With progression to CRC, there is an emergence of strong cytoplasmic HMGB1 (p < 0.001), pronounced at the leading cancer edge within CaP (p < 0.001), and reduction in nuclear HMGB1 (p < 0.001). In CRC, absent nuclear HMGB1 is associated with mismatch repair proteins (p = 0.001). Stronger cytoplasmic HMGB1 is associated with lymph node positivity (p < 0.001) and male sex (p = 0.009). Stronger nuclear (p = 0.011) and cytoplasmic (p = 0.002) HMGB1 is associated with greater CD4+ T-cell density, stronger nuclear HMGB1 is associated with greater FOXP3+ (p < 0.001) and ICOS+ (p = 0.018) lymphocyte density, and stronger nuclear HMGB1 is associated with reduced CD8+ T-cell density (p = 0.022). HMGB1 does not directly impact survival but is associated with an 'immune cold' tumour microenvironment which is associated with poor survival (p < 0.001). HMGB1 may represent a new treatment target for CRC.
ABSTRACT
A treatment with direct healing effects on the gastrointestinal epithelial barrier is desirable for inflammatory bowel disease (IBD). Interleukin-27 (IL-27) is an immunoregulatory cytokine, and oral delivery is an effective treatment in murine models of IBD. We aimed to define IL-27 effects on the human gastrointestinal epithelial barrier. We characterised gene and protein expression of permeability mediators in a human colon-derived organoid model. Functional permeability was determined in an organoid-derived 2D monolayer by transepithelial electrical resistance. IL-27 effects on epithelial innate immune responses were assessed through expression of cytokines, anti-microbial peptides and MUC genes. IL-27 effects on wound healing and proliferation were determined in human colon epithelial cell lines. IL-27 led to restoration of permeability regulation following inflammatory cytokine insult (p = 0.001), associated with differential expression of tight junction mediators with decrease in claudin 2 (p = 0.024) and increase in claudin 4 (p < 0.001), E-cadherin (p < 0.001) and zona occludens (p = 0.0014). IL-27 evoked differential gene expression of epithelial-derived innate immune responses (reduced IL1B and IL18, and increased IL33, HBD1, MUC1 and MUC2; p < 0.012). IL-27 induced epithelial barrier wound healing through restitution (p < 0.001), and increased proliferation (p < 0.001) following injury. Overall, IL-27 provokes mucosal healing of the human gastrointestinal epithelial barrier.
ABSTRACT
BACKGROUND & AIMS: Barrett's esophagus (BE) is a risk factor for esophageal adenocarcinoma but our understanding of how it evolves is poorly understood. We investigated BE gland phenotype distribution, the clonal nature of phenotypic change, and how phenotypic diversity plays a role in progression. METHODS: Using immunohistochemistry and histology, we analyzed the distribution and the diversity of gland phenotype between and within biopsy specimens from patients with nondysplastic BE and those who had progressed to dysplasia or had developed postesophagectomy BE. Clonal relationships were determined by the presence of shared mutations between distinct gland types using laser capture microdissection sequencing of the mitochondrial genome. RESULTS: We identified 5 different gland phenotypes in a cohort of 51 nondysplastic patients where biopsy specimens were taken at the same anatomic site (1.0-2.0 cm superior to the gastroesophageal junction. Here, we observed the same number of glands with 1 and 2 phenotypes, but 3 phenotypes were rare. We showed a common ancestor between parietal cell-containing, mature gastric (oxyntocardiac) and goblet cell-containing, intestinal (specialized) gland phenotypes. Similarly, we have shown a clonal relationship between cardiac-type glands and specialized and mature intestinal glands. Using the Shannon diversity index as a marker of gland diversity, we observed significantly increased phenotypic diversity in patients with BE adjacent to dysplasia and predysplasia compared to nondysplastic BE and postesophagectomy BE, suggesting that diversity develops over time. CONCLUSIONS: We showed that the range of BE phenotypes represents an evolutionary process and that changes in gland diversity may play a role in progression. Furthermore, we showed a common ancestry between gastric and intestinal-type glands in BE.
Subject(s)
Barrett Esophagus , Esophageal Neoplasms , Barrett Esophagus/pathology , Esophageal Neoplasms/pathology , Esophagogastric Junction/pathology , Humans , PhenotypeABSTRACT
BACKGROUND: Functional hyposplenism is a recognized complication of several gastroenterological disorders, including coeliac and inflammatory bowel diseases, and is believed to contribute to the increased infection risk seen in these disorders. SUMMARY: The mechanisms of hyposplenism are poorly understood. In this article, we review possible mechanisms underlying development of functional hyposplenism and discuss implications for its management. KEY MESSAGES: Identifying functional hyposplenism is important, as it may permit earlier recognition and treatment of serious infections through patient education and vaccination.
Subject(s)
Gastrointestinal Diseases , Splenic Diseases , Gastrointestinal Diseases/complications , Humans , Splenic Diseases/complications , Splenic Diseases/therapyABSTRACT
Interleukin (IL)-33 is highly expressed in the nucleus of cells present at barrier sites and signals via the ST2 receptor. IL-33 signalling via ST2 is essential for return to tissue homeostasis after acute inflammation, promoting fibrinogenesis and wound healing at injury sites. However, this wound-healing response becomes aberrant during chronic or sustained inflammation, leading to transforming growth factor beta (TGF-ß) release, excessive extracellular matrix deposition, and fibrosis. This review addresses the role of the IL-33 pathway in fibrotic diseases of the lung, liver, gastrointestinal tract, skin, kidney and heart. In the lung and liver, IL-33 release leads to the activation of pro-fibrotic TGF-ß, and in these sites, IL-33 has clear pro-fibrotic roles. In the gastrointestinal tract, skin, and kidney, the role of IL-33 is more complex, being both pro-fibrotic and tissue protective. Finally, in the heart, IL-33 serves cardioprotective functions by favouring tissue healing and preventing cardiomyocyte death. Altogether, this review indicates the presence of an unclear and delicate balance between resolving and pro-fibrotic capabilities of IL-33, which has a central role in the modulation of type 2 inflammation and fibrosis in response to tissue injury.
ABSTRACT
Colorectal cancer (CRC) remains a leading cause of cancer mortality. Here, we define the colonic epithelial expression of cathelicidin (LL-37) in CRC. Cathelicidin exerts pleotropic effects including anti-microbial and immunoregulatory functions. Genetic knockout of cathelicidin led to increased size and number of colorectal tumours in the azoxymethane-induced murine model of CRC. We aimed to translate this to human disease. The expression of LL-37 in a large (n = 650) fully characterised cohort of treatment-naïve primary human colorectal tumours and 50 matched normal mucosa samples with associated clinical and pathological data (patient age, gender, tumour site, tumour stage [UICC], presence or absence of extra-mural vascular invasion, tumour differentiation, mismatch repair protein status, and survival to 18 years) was assessed by immunohistochemistry. The biological consequences of LL-37 expression on the epithelial barrier and immune cell phenotype were assessed using targeted quantitative PCR gene expression of epithelial permeability (CLDN2, CLDN4, OCLN, CDH1, and TJP1) and cytokine (IL-1ß, IL-18, IL-33, IL-10, IL-22, and IL-27) genes in a human colon organoid model, and CD3+ , CD4+ , and CD8+ lymphocyte phenotyping by immunohistochemistry, respectively. Our data reveal that loss of cathelicidin is associated with human CRC progression, with a switch in expression intensity an early feature of CRC. LL-37 expression intensity is associated with CD8+ T cell infiltrate, influenced by tumour characteristics including mismatch repair protein status. There was no effect on epithelial barrier gene expression. These data offer novel insights into the contribution of LL-37 to the pathogenesis of CRC and as a therapeutic molecule.
Subject(s)
CD8-Positive T-Lymphocytes/pathology , Cathelicidins/metabolism , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Disease Progression , Immunohistochemistry , Aged , Animals , Cohort Studies , Cytokines/genetics , Female , Gene Expression , Humans , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Male , Mice , Organoids , PermeabilityABSTRACT
Cancer comprises a collection of highly proliferative and heterogeneous cells growing within an adaptive and evolving tumour microenvironment. Cancer survival rates have significantly improved following decades of cancer research. However, many experimental and preclinical studies do not translate to the bedside, reflecting the challenges of modelling the complexities and multicellular basis of human disease. Organoids are novel, complex, three-dimensional ex vivo tissue cultures that are derived from embryonic stem cells, induced pluripotent stem cells or tissue-resident progenitor cells, and represent a near-physiological model for studying cancer. Organoids develop by self-organisation, and can accurately represent the diverse genetic, cellular and pathophysiological hallmarks of cancer. In addition, co-culture methods and the ability to genetically manipulate these organoids have widened their utility in cancer research. Organoids thus offer a new and exciting platform for studying cancer and directing personalised therapies. This review aims to highlight how organoids are shaping the future of cancer research.
Subject(s)
Neoplasms/pathology , Organoids/cytology , Animals , Biomedical Research , Cell Culture Techniques , Coculture Techniques , Gene Editing , Humans , Organoids/physiology , Tumor MicroenvironmentABSTRACT
BACKGROUND: The incidence of oesophageal adenocarcinoma is increasing globally. Barrett's oesophagus (BO) is a pre-malignant condition with no biomarker to risk stratify those at highest risk of dysplasia and malignant transformation. METHODS: Subcellular epithelial protein (HMGB1, p53, RUNX3) expression, alongside expression of CD20, CD4, CD8 and Foxp3 to characterise stromal B lymphocyte, and helper, cytotoxic and regulatory T-lymphocyte cell infiltrate, respectively, was assessed by immunohistochemistry in 218 human tissue samples including normal oesophageal/gastric biopsies (n = 39), BO (non-dysplasia, dysplasia, non-dysplastic background from progressors to dysplasia or cancer, n = 121) and oesophageal adenocarcinoma (n = 58). RESULTS: There is a dynamic subcellular epithelial expression of HMGB1 (loss of nuclear, emergence of cytoplasmic), associated with epithelial p53 expression and differential immune cell phenotype in oesophageal neoplastic progression. We identify a protein signature and lymphocyte infiltrate in non-dysplastic BO when progressive disease (dysplasia or adenocarcinoma) is present but not histologically represented in the biopsied field. There is a dynamic stromal lymphocytic infiltrate in oesophageal neoplastic progression. CONCLUSIONS: This data reveals novel insights into the microenvironment of BO and progression towards cancer and identifies a novel high-risk biomarker of disease progression to aid surveillance strategies to identify early progression and impact future incidence of oesophageal cancer.
Subject(s)
Barrett Esophagus/metabolism , Barrett Esophagus/pathology , Cell Transformation, Neoplastic/metabolism , HMGB1 Protein/biosynthesis , Lymphocytes, Tumor-Infiltrating/immunology , Tumor Microenvironment/immunology , Adenocarcinoma/immunology , Adenocarcinoma/metabolism , Barrett Esophagus/immunology , Biomarkers, Tumor/analysis , Biomarkers, Tumor/metabolism , Disease Progression , Esophageal Neoplasms/immunology , Esophageal Neoplasms/metabolism , Humans , Lymphocytes, Tumor-Infiltrating/pathology , Risk AssessmentABSTRACT
The intestine serves as both our largest single barrier to the external environment and the host of more immune cells than any other location in our bodies. Separating these potential combatants is a single layer of dynamic epithelium composed of heterogeneous epithelial subtypes, each uniquely adapted to carry out a subset of the intestine's diverse functions. In addition to its obvious role in digestion, the intestinal epithelium is responsible for a wide array of critical tasks, including maintaining barrier integrity, preventing invasion by microbial commensals and pathogens, and modulating the intestinal immune system. Communication between these epithelial cells and resident immune cells is crucial for maintaining homeostasis and coordinating appropriate responses to disease and can occur through cell-to-cell contact or by the release or recognition of soluble mediators. The objective of this review is to highlight recent literature illuminating how cytokines and chemokines, both those made by and acting on the intestinal epithelium, orchestrate many of the diverse functions of the intestinal epithelium and its interactions with immune cells in health and disease. Areas of focus include cytokine control of intestinal epithelial proliferation, cell death, and barrier permeability. In addition, the modulation of epithelial-derived cytokines and chemokines by factors such as interactions with stromal and immune cells, pathogen and commensal exposure, and diet will be discussed.
Subject(s)
Cytokines/metabolism , Intestinal Mucosa/metabolism , Animals , Apoptosis/genetics , Cell Membrane Permeability , Cell Proliferation , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/immunology , Cell Transformation, Neoplastic/metabolism , Chemokines/metabolism , Humans , Immune System/immunology , Immune System/metabolism , Immunity, Mucosal , Intestinal Mucosa/immunologyABSTRACT
Background: Epidemiological studies indicate that the use of artificial sweeteners doubles the risk for Crohn's disease (CD). Herein, we experimentally quantified the impact of 6-week supplementation with a commercial sweetener (Splenda; ingredients sucralose maltodextrin, 1:99, w/w) on both the severity of CD-like ileitis and the intestinal microbiome alterations using SAMP1/YitFc (SAMP) mice. Methods: Metagenomic shotgun DNA sequencing was first used to characterize the microbiome of ileitis-prone SAMP mice. Then, 16S rRNA microbiome sequencing, quantitative polymerase chain reaction, fluorescent in situ hybridization (FISH), bacterial culture, stereomicroscopy, histology, and myeloperoxidase (MPO) activity analyses were then implemented to compare the microbiome and ileitis phenotype in SAMP with that of control ileitis-free AKR/J mice after Splenda supplementation. Results: Metagenomics indicated that SAMP mice have a gut microbial phenotype rich in Bacteroidetes, and experiments showed that Helicobacteraceae did not have an exacerbating effect on ileitis. Splenda did not increase the severity of (stereomicroscopic/histological) ileitis; however, biochemically, ileal MPO activity was increased in SAMP treated with Splenda compared with nonsupplemented mice (P < 0.022) and healthy AKR mice. Splenda promoted dysbiosis with expansion of Proteobacteria in all mice, and E. coli overgrowth with increased bacterial infiltration into the ileal lamina propria of SAMP mice. FISH showed increase malX gene-carrying bacterial clusters in the ilea of supplemented SAMP (but not AKR) mice. Conclusions: Splenda promoted gut Proteobacteria, dysbiosis, and biochemical MPO reactivity in a spontaneous model of (Bacteroidetes-rich) ileal CD. Our results indicate that although Splenda may promote parallel microbiome alterations in CD-prone and healthy hosts, this did not result in elevated MPO levels in healthy mice, only CD-prone mice. The consumption of sucralose/maltodextrin-containing foods might exacerbate MPO intestinal reactivity only in individuals with a pro-inflammatory predisposition, such as CD.
Subject(s)
Crohn Disease/pathology , Dysbiosis/physiopathology , Ileitis/pathology , Intestinal Mucosa/pathology , Sucrose/analogs & derivatives , Sweetening Agents/adverse effects , Animals , Bacteroidetes/drug effects , Bacteroidetes/genetics , Crohn Disease/metabolism , Disease Models, Animal , Female , Humans , Ileitis/metabolism , In Situ Hybridization, Fluorescence , Intestinal Mucosa/metabolism , Male , Mice , Mice, Inbred AKR , Microbiota , Peroxidase/metabolism , Proteobacteria/drug effects , Proteobacteria/genetics , RNA, Ribosomal, 16S/genetics , Sucrose/adverse effectsABSTRACT
Commensal bacteria are critical for physiological functions in the gut, and dysbiosis in the gut may cause diseases. In this article, we report that mice deficient in cathelin-related antimicrobial peptide (CRAMP) were defective in the development of colon mucosa and highly sensitive to dextran sulfate sodium (DSS)-elicited colitis, as well as azoxymethane-mediated carcinogenesis. Pretreatment of CRAMP-/- mice with antibiotics markedly reduced the severity of DSS-induced colitis, suggesting CRAMP as a limiting factor on dysbiosis in the colon. This was supported by observations that wild-type (WT) mice cohoused with CRAMP-/- mice became highly sensitive to DSS-induced colitis, and the composition of fecal microbiota was skewed by CRAMP deficiency. In particular, several bacterial species that are typically found in oral microbiota, such as Mogibacterium neglectum, Desulfovibrio piger, and Desulfomicrobium orale, were increased in feces of CRAMP-/- mice and were transferred to WT mice during cohousing. When littermates of CRAMP+/- parents were examined, the composition of the fecal microbiota of WT pups and heterozygous parents was similar. In contrast, although the difference in fecal microbiota between CRAMP-/- and WT pups was small early on after weaning and single mouse housing, there was an increasing divergence with prolonged single housing. These results indicate that CRAMP is critical in maintaining colon microbiota balance and supports mucosal homeostasis, anti-inflammatory responses, and protection from carcinogenesis.
Subject(s)
Antimicrobial Cationic Peptides/metabolism , Colon/metabolism , Colon/microbiology , Gastrointestinal Microbiome/physiology , Homeostasis/physiology , Microbiota/physiology , Animals , Colitis/metabolism , Colitis/microbiology , Disease Models, Animal , Feces/microbiology , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Mice , Mice, Inbred C57BL , Proteins/metabolism , CathelicidinsABSTRACT
BACKGROUND: If treatment with intravenous steroids fail, inflammatory bowel disease patients with acute severe colitis face systemic anti-tumor necrosis factor biologic rescue therapy or colectomy. Interleukin (IL)-27 is a cytokine with an immunosuppressive role in adaptive immune responses. However, the IL-27 receptor complex is also expressed on innate immune cells, and there is evidence that IL-27 can impact the function of innate cell subsets, although this particular functionality in vivo is not understood. Our aim was to define the efficacy of IL-27 in acute severe colitis and characterize novel IL-27-driven mechanisms of immunosuppression in the colonic mucosa. METHODS: We assessed oral delivery of Lactococcus lactis expressing an IL-27 hyperkine on the innate immune response in vivo in a genetically intact, noninfective, acute murine colitis model induced by intrarectal instillation of 2,4,6-trinitrobenzenesulfonic acid in SJL/J mice. RESULTS: IL-27 attenuates acute severe colitis through the reduction of colonic mucosal neutrophil infiltrate associated with a decreased CXC chemokine gradient. This suppression was T cell independent and IL-10 dependent, initially featuring enhanced mucosal IL-10. IL-27 was associated with a reduction in colonic proinflammatory cytokines and induced a multifocal, strong, positive nuclear expression of phosphorylated STAT-1 in mucosal epithelial cells. CONCLUSION: We have defined novel mechanisms of IL-27 immunosuppression toward colonic innate immune responses in vivo. Mucosal delivery of IL-27 has translational potential as a novel therapeutic for inflammatory bowel disease, and it is a future mucosal directed rescue therapy in acute severe inflammatory bowel disease.
Subject(s)
Colitis/drug therapy , Colon/immunology , Immunity, Innate , Interleukin-10/metabolism , Interleukin-27/pharmacology , Intestinal Mucosa/metabolism , Acute Disease , Animals , Colitis/chemically induced , Colon/physiopathology , Disease Models, Animal , Inflammation/pathology , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/pathology , Interleukin-27/immunology , Intestinal Mucosa/drug effects , Male , Mice , Mice, Knockout , T-Lymphocytes/metabolism , Trinitrobenzenesulfonic Acid/administration & dosageABSTRACT
Inflammatory bowel disease (IBD) is an inflammatory disorder of the intestine that affects an estimated 329 per 100,000 people in the United States and is increasing in incidence within a number of cultures worldwide. Likely due to its incompletely understood pathophysiology and etiology, the standard treatments for IBD are only efficacious in subsets of patients and often do not induce lasting remission. As a result, novel therapies are needed. The success of anti-tumor necrosis factor-α treatment in a subset of patients with IBD demonstrated that therapy targeting a single cytokine could be efficacious in IBD, and clinical trials investigating the blockade of a variety of cytokines have commenced. Interleukin (IL) 27 is a relatively recently discovered type I cytokine with established roles in infectious disease, autoimmunity, and cancer in a variety of organs. IL-27 was identified as a candidate gene for IBD, and a number of studies in mouse models of IBD have demonstrated that IL-27 therapy is protective. However, in contrast to these investigations, genetic deletion of the IL-27 receptor has been shown to be protective in some mouse models of IBD. The purpose of this review is to highlight the recent literature investigating the role of IL-27 in IBD and to discuss the possible explanations for the sometimes conflicting results of these studies. Evidence supporting IL-27 therapy as a treatment for IBD will also be discussed.
Subject(s)
Inflammatory Bowel Diseases/drug therapy , Interleukin-27/genetics , Interleukin-27/pharmacology , Intestinal Mucosa/metabolism , Animals , Disease Models, Animal , Gene Expression , Humans , Immunity, Innate , Inflammatory Bowel Diseases/genetics , Intestinal Mucosa/pathology , MiceABSTRACT
The microbiota of the human metaorganism is not a mere bystander. These microbes have coevolved with us and are pivotal to normal development and homoeostasis. Dysbiosis of the GI microbiota is associated with many disease susceptibilities, including obesity, malignancy, liver disease and GI pathology such as IBD. It is clear that there is direct and indirect crosstalk between this microbial community and host immune response. However, the precise mechanism of this microbial influence in disease pathogenesis remains elusive and is now a major research focus. There is emerging literature on the role of the microbiota in the pathogenesis of autoimmune disease, with clear and increasing evidence that changes in the microbiota are associated with some of these diseases. Examples include type 1 diabetes, coeliac disease and rheumatoid arthritis, and these contribute significantly to global morbidity and mortality. Understanding the role of the microbiota in autoimmune diseases may offer novel insight into factors that initiate and drive disease progression, stratify patient risk for complications and ultimately deliver new therapeutic strategies. This review summarises the current status on the role of the microbiota in autoimmune diseases.
Subject(s)
Autoimmune Diseases/microbiology , Gastrointestinal Tract/microbiology , Microbiota/physiology , Arthritis, Rheumatoid/microbiology , Celiac Disease/microbiology , Diabetes Mellitus, Type 1/microbiology , HumansABSTRACT
IL-22 has multiple activities ranging from tissue repair to inflammation. To characterize the pathogenicity and plasticity of cells that produce IL-22, a novel reporter mouse strain was generated. Homeostatic IL-22 reporter expression was observed in intestinal lymphoid cells identified as CD4 T cells and ILC3 cells. In a model of inflammatory bowel disease, CD4 T cells strongly expressed the IL-22 reporter in mesenteric lymph node. To examine plasticity of IL-22(+) T cells, they were purified after generation in vitro or in vivo from inflamed colon, and then cultured under Th1, Th2, or Th17 conditions. In vitro-generated IL-22(+) CD4 T cells showed relatively durable IL-22 expression under Th1 or Th2 conditions, whereas in vivo-generated cells rapidly lost IL-22 expression under these conditions. In vitro-generated cells could not be diverted to express Th1 or Th2 cytokines despite the expression of "master regulators." In vivo-generated cells could be diverted, at very low frequency, to express Th1 or Th2 cytokines. Both in vitro- and in vivo-generated cells could be induced in vitro to express high levels of IL-17A and IL-17F, assigning them to a "Th17 biased" class. However, IL-27 potently downregulated IL-22 expression. To examine IL-22(+) T cell pathogenicity, in vitro-generated cells were transferred into Rag1(-/-) mice, retaining the modest reporter expression and inducing moderate colitis. In contrast, IL-22 expressers from colitic mice, transferred into secondary hosts, lost reporter expression, acquired high T-bet and modest IFNγ and IL-17 expression, and induced severe colitis. These findings are consistent with a model of strong polarization under optimal in vitro conditions, but a plastic state of T cells in vivo.
ABSTRACT
Gastric cancer remains highly prevalent and accounts for a notable proportion of global cancer mortality. This cancer is also associated with poor survival rates. Understanding the genetic basis of gastric cancer will offer insights into its pathogenesis, help identify new biomarkers and novel treatment targets, aid prognostication and could be central to developing individualized treatment strategies in the future. An inherited component contributes to <3% of gastric cancers; the majority of genetic changes associated with gastric cancer are acquired. Over the past few decades, advances in technology and high-throughput analysis have improved understanding of the molecular aspects of the pathogenesis of gastric cancer. These aspects are multifaceted and heterogeneous and represent a wide spectrum of several key genetic influences, such as chromosomal instability, microsatellite instability, changes in microRNA profile, somatic gene mutations or functional single nucleotide polymorphisms. These genetic aspects of the pathogenesis of gastric cancer will be addressed in this Review.
Subject(s)
Stomach Neoplasms/genetics , Chromosomal Instability/genetics , Genetic Predisposition to Disease/genetics , Helicobacter Infections/complications , Helicobacter Infections/genetics , Humans , Microsatellite Instability , Polymorphism, Single Nucleotide/genetics , Stomach Neoplasms/etiologyABSTRACT
: Inflammatory bowel disease accounts for significant patient morbidity in the Western world. Several immunosuppressive therapies are available but are associated with potential significant adverse effects. In addition, there remains a cohort of patients with refractory or relapsing disease. Therefore, the search for novel therapeutic agents continues. In this review, we evaluate the role of a number of designated cytokines that are candidates in the pathogenesis of inflammatory bowel disease and discuss how their manipulation has been explored as a therapeutic strategy for this disease. The interleukins (ILs) chosen for discussion reflect those that currently show most promise as future therapeutic targets, as well as discussing the role of some of the most recently identified ILs, such as IL-27, IL-33, IL-35, and IL-22, in this context.
Subject(s)
Immunologic Factors/therapeutic use , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/metabolism , Interleukins/metabolism , Tumor Necrosis Factor-alpha/antagonists & inhibitors , HumansABSTRACT
BACKGROUND & AIMS: Treatment of inflammatory bowel disease would benefit from specific targeting of therapeutics to the intestine. We developed a strategy for localized delivery of the immunosuppressive cytokine interleukin (IL)-27, which is synthesized actively in situ by the food-grade bacterium Lactococcus lactis (LL-IL-27), and tested its ability to reduce colitis in mice. METHODS: The 2 genes encoding mouse IL-27 were synthesized with optimal codon use for L lactis and joined with a linker; a signal sequence was added to allow for product secretion. The construct was introduced into L lactis. Colitis was induced via transfer of CD4(+)CD45RB(hi) T cells into Rag(-/-) mice to induce colitis; 7.5 weeks later, LL-IL-27 was administered to mice via gavage. Intestinal tissues were collected and analyzed. RESULTS: LL-IL-27 administration protected mice from T-cell transfer-induced enterocolitis and death. LL-IL-27 reduced disease activity scores, pathology features of large and small bowel, and levels of inflammatory cytokines in colonic tissue. LL-IL-27 also reduced the numbers of CD4(+) and IL-17(+) T cells in gut-associated lymphoid tissue. The effects of LL-IL-27 required production of IL-10 by the transferred T cells. LL-IL-27 was more effective than either LL-IL-10 or systemic administration of recombinant IL-27 in reducing colitis in mice. LL-IL-27 also reduced colitis in mice after administration of dextran sodium sulfate. CONCLUSIONS: LL-IL-27 reduces colitis in mice by increasing the production of IL-10. Mucosal delivery of LL-IL-27 could be a more effective and safer therapy for inflammatory bowel disease.
Subject(s)
Drug Delivery Systems/methods , Enterocolitis/immunology , Immunologic Factors/administration & dosage , Inflammatory Bowel Diseases , Interleukin-10/immunology , Interleukins/administration & dosage , Intestinal Mucosa/immunology , Lactococcus lactis , Administration, Oral , Animals , Disease Models, Animal , Immunologic Factors/pharmacology , Interleukins/immunology , Intestinal Mucosa/drug effects , Mice , T-Lymphocytes , Transformation, BacterialABSTRACT
Genetic epidemiology is an important discipline that is helping to unravel the aetiology and pathogenesis of complex human diseases. In the context of gastrointestinal malignancy, the paradigm model of host genetic influence on disease outcome is H. pylori-associated gastric adenocarcinoma. This cancer represents a classic example of an inflammation-induced malignancy and highlights the importance of host genetics in disease development. This chapter gives an insight into how genetic epidemiology can play an important role in the development of gastric cancer. Increasing our understanding of host genetics in cancer development may allow particularly susceptible individuals to be targeted for screening or treatment to reduce risk of future malignant transformation.