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Lin W, Liu S, Huang Z, Li H, Lu T, Luo Y, Zhong J, Xu Z, Liu Y, Li Y, Li P, Xu Q, Cai J, Li H, Chen XL. Mass cytometry and single-cell RNA sequencing reveal immune cell characteristics of active and inactive phases of Crohn's disease. Front Med (Lausanne) 2023; 9:1064106. [PMID: 36714133 PMCID: PMC9878392 DOI: 10.3389/fmed.2022.1064106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 12/14/2022] [Indexed: 01/13/2023] Open
Abstract
Objectives For Crohn's disease (CD), the alternation of the active phase and inactive phase may be related to humoral immunity and cellular immunity. This study aims to understand the characteristics of immune cells in patients with active CD (CDa) and inactive CD (CDin). Methods Mass cytometry (CyTOF) and single-cell RNA sequencing (scRNA-seq) data about CDa, CDin, and healthy control (HC) were included. CyTOF analysis was performed to capture gated subsets, including T cells, T regulatory (Treg) cells, B cells, innate immune cells, and natural killer (NK) cells. Differential analysis was used to identify different immune cell subsets among CDa, CDin, and HC. ScRNA-seq analysis was used to verify the results of CyTOF. CD-related signaling pathways were obtained using KEGG pathway enrichment analysis. CellChat analysis was used to infer the cell communication network among immune cell subsets. Results Compared to patients with CDin, patients with CDa had higher abundances of CD16+CD38+CD4+CXCR3+CCR6+ naive T cells, HLA-DR+CD38+IFNγ+TNF+ effector memory (EM) T cells, HLA-DR+IFNγ+ naive B cells, and CD14++CD11C+IFNγ+IL1B+ monocytes. KEGG analysis showed the similarity of pathway enrichment for the earlier four subsets, such as thermogenesis, oxidative phosphorylation, and metabolic pathways. The patients with CDin were characterized by an increased number of CD16+CD56dimCD44+HLA-DR+IL22+ NK cells. Compared to HC, patients with CDa demonstrated a low abundance of HLA-DR+CCR6+ NK cells and a high abundance of FOXP3+CD44+ EM Tregs. CellChat analysis revealed the interaction network of cell subsets amplifying in CDa compared with CDin. Conclusion Some immune subsets cells were identified for CDa and CDin. These cells may be related to the occurrence and development of CD and may provide assistance in disease diagnosis and treatment.
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Affiliation(s)
- Wenjia Lin
- School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Shiying Liu
- School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhuojian Huang
- School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Haiwen Li
- Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Tianyu Lu
- School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yongxin Luo
- School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jiamin Zhong
- School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zewen Xu
- School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yu Liu
- Department of Medical Statistics, School of Public Health, Sun Yat-sen University, Guangzhou, China
| | - Yanwu Li
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China,Pi-Wei Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Peiwu Li
- The First Affiliated Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Qian Xu
- School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jiazhong Cai
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, China,Pi-Wei Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Huibiao Li
- The First Affiliated Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xin-lin Chen
- School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China,*Correspondence: Xin-lin Chen,
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Sarvestani SK, Signs S, Hu B, Yeu Y, Feng H, Ni Y, Hill DR, Fisher RC, Ferrandon S, DeHaan RK, Stiene J, Cruise M, Hwang TH, Shen X, Spence JR, Huang EH. Induced organoids derived from patients with ulcerative colitis recapitulate colitic reactivity. Nat Commun 2021; 12:262. [PMID: 33431859 PMCID: PMC7801686 DOI: 10.1038/s41467-020-20351-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 11/30/2020] [Indexed: 02/08/2023] Open
Abstract
The pathogenesis of ulcerative colitis (UC), a major type of inflammatory bowel disease, remains unknown. No model exists that adequately recapitulates the complexity of clinical UC. Here, we take advantage of induced pluripotent stem cells (iPSCs) to develop an induced human UC-derived organoid (iHUCO) model and compared it with the induced human normal organoid model (iHNO). Notably, iHUCOs recapitulated histological and functional features of primary colitic tissues, including the absence of acidic mucus secretion and aberrant adherens junctions in the epithelial barrier both in vitro and in vivo. We demonstrate that the CXCL8/CXCR1 axis was overexpressed in iHUCO but not in iHNO. As proof-of-principle, we show that inhibition of CXCL8 receptor by the small-molecule non-competitive inhibitor repertaxin attenuated the progression of UC phenotypes in vitro and in vivo. This patient-derived organoid model, containing both epithelial and stromal compartments, will generate new insights into the underlying pathogenesis of UC while offering opportunities to tailor interventions to the individual patient.
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Affiliation(s)
- Samaneh K Sarvestani
- Department of Cancer Biology, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA
| | - Steven Signs
- Department of Cancer Biology, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA
| | - Bo Hu
- Department of Quantitative Health Sciences, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA
| | - Yunku Yeu
- Department of Quantitative Health Sciences, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA
| | - Hao Feng
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Ying Ni
- Department of Quantitative Health Sciences, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA
| | - David R Hill
- Department of Internal Medicine, Gastroenterology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Robert C Fisher
- Department of Cancer Biology, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA
| | - Sylvain Ferrandon
- Department of Cancer Biology, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA
| | - Reece K DeHaan
- Department of Colorectal Surgery, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Jennifer Stiene
- Department of Cancer Biology, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA
| | - Michael Cruise
- Department of Pathology, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Tae Hyun Hwang
- Department of Quantitative Health Sciences, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA
| | - Xiling Shen
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Jason R Spence
- Department of Internal Medicine, Gastroenterology, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Emina H Huang
- Department of Cancer Biology, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA.
- Department of Colorectal Surgery, Cleveland Clinic, Cleveland, OH, 44195, USA.
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3
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Rees WD, Sly LM, Steiner TS. How do immune and mesenchymal cells influence the intestinal epithelial cell compartment in inflammatory bowel disease? Let's crosstalk about it! J Leukoc Biol 2020; 108:309-321. [PMID: 32057139 DOI: 10.1002/jlb.3mir0120-567r] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 01/12/2020] [Accepted: 01/17/2020] [Indexed: 12/18/2022] Open
Abstract
Intestinal epithelial cells provide a front line of defense by establishing a barrier against food Ags, pathogens, and commensal microorganisms. This defense includes the establishment of a tolerogenic environment in the gastrointestinal (GI) tract. The intestinal epithelium replenishes itself by cell turnover every 4-5 days, and this process is facilitated by various pathways of communication between the intestinal epithelial cells (IECs), the underlying stromal cell network, and professional immune cells, which together help establish a proper intestinal stem cell (ISC) niche in the crypt. However, during a state of inflammation, such as in inflammatory bowel diseases (IBD), these communication pathways can be altered, and this can lead to the development of inflammatory IECs within the crypt that further drive inflammation. Here, we review the current literature looking at crosstalk between immune cells, stromal cells, and IECs: how does the immune system potentially alter the ISC niche, and how do IECs influence intestinal immunity? We discuss the latest research using single cell RNA sequencing and intestinal organoid cultures to help answer these questions. A better understanding of this complex crosstalk can help lead to a better understanding of intestinal biology in general, and more efficient therapeutic approaches to treat IBD.
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Affiliation(s)
- William D Rees
- Department of Medicine, BC Children's Hospital Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Laura M Sly
- Department of Pediatrics, BC Children's Hospital Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Theodore S Steiner
- Department of Medicine, BC Children's Hospital Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
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A primary human macrophage-enteroid co-culture model to investigate mucosal gut physiology and host-pathogen interactions. Sci Rep 2017; 7:45270. [PMID: 28345602 PMCID: PMC5366908 DOI: 10.1038/srep45270] [Citation(s) in RCA: 244] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 02/23/2017] [Indexed: 12/22/2022] Open
Abstract
Integration of the intestinal epithelium and the mucosal immune system is critical for gut homeostasis. The intestinal epithelium is a functional barrier that secludes luminal content, senses changes in the gut microenvironment, and releases immune regulators that signal underlying immune cells. However, interactions between epithelial and innate immune cells to maintain barrier integrity and prevent infection are complex and poorly understood. We developed and characterized a primary human macrophage-enteroid co-culture model for in-depth studies of epithelial and macrophage interactions. Human intestinal stem cell-derived enteroid monolayers co-cultured with human monocyte-derived macrophages were used to evaluate barrier function, cytokine secretion, and protein expression under basal conditions and following bacterial infection. Macrophages enhanced barrier function and maturity of enteroid monolayers as indicated by increased transepithelial electrical resistance and cell height. Communication between the epithelium and macrophages was demonstrated through morphological changes and cytokine production. Intraepithelial macrophage projections, efficient phagocytosis, and stabilized enteroid barrier function revealed a coordinated response to enterotoxigenic and enteropathogenic E. coli infections. In summary, we have established the first primary human macrophage-enteroid co-culture system, defined conditions that allow for a practical and reproducible culture model, and demonstrated its suitability to study gut physiology and host responses to enteric pathogens.
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Dicay MS, Hirota CL, Ronaghan NJ, Peplowski MA, Zaheer RS, Carati CA, MacNaughton WK. Interferon-γ suppresses intestinal epithelial aquaporin-1 expression via Janus kinase and STAT3 activation. PLoS One 2015; 10:e0118713. [PMID: 25793528 PMCID: PMC4405000 DOI: 10.1371/journal.pone.0118713] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 01/09/2015] [Indexed: 12/29/2022] Open
Abstract
Inflammatory bowel diseases are associated with dysregulated electrolyte and water transport and resultant diarrhea. Aquaporins are transmembrane proteins that function as water channels in intestinal epithelial cells. We investigated the effect of the inflammatory cytokine, interferon-γ, which is a major player in inflammatory bowel diseases, on aquaporin-1 expression in a mouse colonic epithelial cell line, CMT93. CMT93 monolayers were exposed to 10 ng/mL interferon-γ and aquaporin-1 mRNA and protein expressions were measured by real-time PCR and western blot, respectively. In other experiments, CMT93 cells were pretreated with inhibitors or were transfected with siRNA to block the effects of Janus kinases, STATs 1 and 3, or interferon regulatory factor 2, prior to treatment with interferon-γ. Interferon-γ decreased aquaporin-1 expression in mouse intestinal epithelial cells in a manner that did not depend on the classical STAT1/JAK2/IRF-1 pathway, but rather, on an alternate Janus kinase (likely JAK1) as well as on STAT3. The pro-inflammatory cytokine, interferon-γ may contribute to diarrhea associated with intestinal inflammation in part through regulation of the epithelial aquaporin-1 water channel via a non-classical JAK/STAT receptor signalling pathway.
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Affiliation(s)
- Michael S Dicay
- Inflammation Research Network and Department of Physiology and Pharmacology, University of Calgary, Calgary, Canada
| | - Christina L Hirota
- Inflammation Research Network and Department of Physiology and Pharmacology, University of Calgary, Calgary, Canada
| | - Natalie J Ronaghan
- Inflammation Research Network and Department of Physiology and Pharmacology, University of Calgary, Calgary, Canada
| | - Michael A Peplowski
- Inflammation Research Network and Department of Physiology and Pharmacology, University of Calgary, Calgary, Canada
| | - Raza S Zaheer
- Inflammation Research Network and Department of Physiology and Pharmacology, University of Calgary, Calgary, Canada
| | - Colin A Carati
- Department of Anatomy and Histology, Flinders University, Bedford Park, Australia
| | - Wallace K MacNaughton
- Inflammation Research Network and Department of Physiology and Pharmacology, University of Calgary, Calgary, Canada
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6
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Duell BL, Carey AJ, Tan CK, Cui X, Webb RI, Totsika M, Schembri MA, Derrington P, Irving-Rodgers H, Brooks AJ, Cripps AW, Crowley M, Ulett GC. Innate transcriptional networks activated in bladder in response to uropathogenic Escherichia coli drive diverse biological pathways and rapid synthesis of IL-10 for defense against bacterial urinary tract infection. THE JOURNAL OF IMMUNOLOGY 2011; 188:781-92. [PMID: 22184725 DOI: 10.4049/jimmunol.1101231] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Early transcriptional activation events that occur in bladder immediately following bacterial urinary tract infection (UTI) are not well defined. In this study, we describe the whole bladder transcriptome of uropathogenic Escherichia coli (UPEC) cystitis in mice using genome-wide expression profiling to define the transcriptome of innate immune activation stemming from UPEC colonization of the bladder. Bladder RNA from female C57BL/6 mice, analyzed using 1.0 ST-Affymetrix microarrays, revealed extensive activation of diverse sets of innate immune response genes, including those that encode multiple IL-family members, receptors, metabolic regulators, MAPK activators, and lymphocyte signaling molecules. These were among 1564 genes differentially regulated at 2 h postinfection, highlighting a rapid and broad innate immune response to bladder colonization. Integrative systems-level analyses using InnateDB (http://www.innatedb.com) bioinformatics and ingenuity pathway analysis identified multiple distinct biological pathways in the bladder transcriptome with extensive involvement of lymphocyte signaling, cell cycle alterations, cytoskeletal, and metabolic changes. A key regulator of IL activity identified in the transcriptome was IL-10, which was analyzed functionally to reveal marked exacerbation of cystitis in IL-10-deficient mice. Studies of clinical UTI revealed significantly elevated urinary IL-10 in patients with UPEC cystitis, indicating a role for IL-10 in the innate response to human UTI. The whole bladder transcriptome presented in this work provides new insight into the diversity of innate factors that determine UTI on a genome-wide scale and will be valuable for further data mining. Identification of protective roles for other elements in the transcriptome will provide critical new insight into the complex cascade of events that underpin UTI.
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Affiliation(s)
- Benjamin L Duell
- School of Medical Sciences, Centre for Medicine and Oral Health, Griffith University Gold Coast Campus, Queensland 4222, Australia
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7
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Kelly JC, Lungchukiet P, Macleod RJ. Extracellular Calcium-Sensing Receptor Inhibition of Intestinal EpithelialTNF Signaling Requires CaSR-Mediated Wnt5a/Ror2 Interaction. Front Physiol 2011; 2:17. [PMID: 21603229 PMCID: PMC3093814 DOI: 10.3389/fphys.2011.00017] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 03/31/2011] [Indexed: 01/20/2023] Open
Abstract
Tumor necrosis factor alpha (TNFα) and its receptor TNFR1 play a central role in the development of colitis-associated colon cancer. To understand a role for the extracellular calcium-sensing receptor (CaSR) and its non-canonical Wnt mediators, Wnt5a/Ror2, we used reductionistic systems. We added lipopolysaccharide (LPS) to mouse peritoneal macrophages, RAW264.7 cells, a murine macrophage cell line, and 18Co colonic myofibroblasts, to stimulate TNFα secretion and then activated endogenous CaSR. CaSR activation inhibited TNFα secretion, which in RAW264.7 cells knockdown of CaSR by short-interfering RNA (siRNA) duplex reversed. LPS-stimulated NFκB promoter activity in RAW264.7 cells was inhibited by CaSR activation with Ca2+ or other polyvalent CaSR agonists. Reducing CaSR expression with siRNA duplex prevented this inhibition. Following LPS addition to CaSR–HEK cells or RAW264.7 macrophages, CaSR stimulation deneddylated Cullin1. Wnt5a added to HT-29 cells which overexpressed Ror2 or T84 monolayers treated with 3 mM Ca2+ reduced TNFR1 protein expression ∼70%. TNFα/INFγ addition to high resistance T84 monolayers reduced transepithelial resistance 50% within 4 h. CaSR activation (3 mM Ca2+) together with rhWnt5a (200 ng/ml) prevented this reduction while Wnt3a addition had no effect. LPS-stimulated TNFα secretion from RAW264.7 cells was not effected by rhWnt5a but increased 10-fold by Wnt3a. Together our results suggest that following LPS challenge, CaSR activation will inhibit NFκB activity and reduce TNFα secretion from macrophages and stroma while Wnt5a/Ror2 engagement on intestinal epithelia reduces TNFR1 expression, allowing TNFα signaling to be titrated. Our results also suggest that canonical Wnt signaling may enhance TLR4 stimulation of TNFα secretion from murine macrophages.
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8
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Wang A, Fernando M, Leung G, Phan V, Smyth D, McKay DM. Exacerbation of oxazolone colitis by infection with the helminth Hymenolepis diminuta: involvement of IL-5 and eosinophils. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:2850-9. [PMID: 21037078 DOI: 10.2353/ajpath.2010.100537] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Substantial data show that infection with helminth parasites ameliorates colitis; however, oxazolone-induced colitis is exaggerated in mice infected with the tapeworm, Hymenolepis diminuta. We tested the hypothesis that the IL-5 response to helminth infection enhances the severity of oxazolone-induced colitis. Mice were infected with H. diminuta and 8 days later were treated with oxazolone ± anti-IL-5 antibodies. Colitis was assessed 72 hours postoxazolone treatment by disease activity scores, myeloperoxidase activity, and histopathology. Other mice received injections of a replication-deficient adenovirus that carried the IL-5 (Ad.IL-5) gene or a control adenovirus (Ad.delete) ± oxazolone. The effect of H. diminuta+oxazolone in CCL11/CCL22 (eotaxin-1 and 2) knockout (KO) mice was determined. Helminth infection and Ad.IL-5 treatment increased IL-5 and eosinophil numbers. In vivo neutralization of IL-5 significantly reduced the severity of colitis in H. diminuta+oxazolone-treated mice, and H. diminuta did not exaggerate oxazolone-induced colitis in CCL11/CCL22 KO mice. Mice receiving Ad.IL-5 only had no colitis, while oxazolone-induced colitis was more severe in animals cotreated with Ad.IL-5 (Ad.delete + oxazolone was not significantly different from oxazolone only). Thus, while there is much to be gleaned about antiinflammatory mechanisms from rodent-helminth model systems, these data illustrate the caveat that infection with helminth parasites as a therapy could be contraindicated in patients with eosinophilia or elevated IL-5 unless coupled to appropriate measures to block IL-5 and/or eosinophil activity.
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Affiliation(s)
- Arthur Wang
- Gastrointestinal Research Group, Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
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9
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Beaurepaire C, Smyth D, McKay DM. Interferon-gamma regulation of intestinal epithelial permeability. J Interferon Cytokine Res 2010; 29:133-44. [PMID: 19196071 DOI: 10.1089/jir.2008.0057] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The maintenance and regulation of the barrier function of the epithelial lining of the intestine are important homeostatic events, serving to allow selective absorption from the gut lumen while simultaneously limiting the access of bacteria into the mucosa. Interferon-gamma is a pleiotrophic cytokine produced predominantly by natural kill cells and CD4+ T cells that under normal circumstances, and particularly during infection or inflammation, will be a component of the intestinal milieu. Use of colon-derived epithelial cell lines and, to a less extent, murine in vivo analyses, have revealed that interferon-gamma (IFN-gamma) can increase epithelial permeability as gauged by markers of paracellular permeability and bacterial transcytosis, with at least a portion of the bacteria using the transcellular permeation pathway. In this review, we describe the main characteristics of epithelial permeability and then focus on the ability of IFN-gamma to increase epithelial permeability, and the mechanism(s) thereof.
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Affiliation(s)
- Cécile Beaurepaire
- Gastrointestinal Research Group, Department of Physiology and Biophysics, University of Calgary, Calgary, Alberta, Canada
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Hunter MM, Wang A, Parhar KS, Johnston MJG, Van Rooijen N, Beck PL, McKay DM. In vitro-derived alternatively activated macrophages reduce colonic inflammation in mice. Gastroenterology 2010; 138:1395-405. [PMID: 20044996 DOI: 10.1053/j.gastro.2009.12.041] [Citation(s) in RCA: 241] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Revised: 12/08/2009] [Accepted: 12/15/2009] [Indexed: 12/26/2022]
Abstract
BACKGROUND & AIMS Infection with the rat tapeworm Hymenolepis diminuta reduces the severity of dinitrobenzene sulfonic acid (DNBS)-induced colitis in mice. Infection with H. diminuta increases colonic expression of arginase-1 and found in inflammatory zone 1 (FIZZ1), markers of alternatively activated macrophages (AAMs). We investigated whether AAMs have anticolitic effects. METHODS Normal or macrophage-depleted Balb/c mice were infected with H. diminuta; some mice were given DNBS, and the severity of colitis was assessed by disease activity scores, myeloperoxidase activity, and histologic examination. AAMs were also differentiated in vitro, given to mice by intraperitoneal or intravenous injection, and the effects on DNBS-induced colitis were determined. Numbers of AAMs were assessed in biopsy specimens from patients with Crohn's disease. RESULTS Depletion of intestinal macrophages using clodronate-liposomes prevented the anticolitic effect of infection with H. diminuta. Injection of AAMs, but not classically activated macrophages, significantly reduced the severity of DNBS-induced colitis. The AAM-induced, anticolitic effect was accompanied by increased interleukin (IL)-10 production from mitogen-stimulated spleen cells; in vivo neutralization of IL-10 partially reduced the effects of AAM transfer. Patients with active CD had reduced numbers of CD68(+)CD206(+) macrophages (which indicate AAM), whereas biopsy specimens from patients with inactive CD had increased numbers of these cells. CONCLUSIONS Analysis of the H. diminuta-murine DNBS system identified the AAM, which, when administered to mice, significantly reduced DNBS-induced colitis. The ability to derive AAMs from patients' blood suggests that adoptive transfer of these cells could be a novel approach to inflammatory bowel disease.
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Affiliation(s)
- Meaghan M Hunter
- Intestinal Disease Research Program, McMaster University, Hamilton, Ontario, Canada
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11
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Fang HW, Fang SB, Chiang Chiau JS, Yeung CY, Chan WT, Jiang CB, Cheng ML, Lee HC. Inhibitory effects of Lactobacillus casei subsp. rhamnosus on Salmonella lipopolysaccharide-induced inflammation and epithelial barrier dysfunction in a co-culture model using Caco-2/peripheral blood mononuclear cells. J Med Microbiol 2010; 59:573-579. [PMID: 20110387 DOI: 10.1099/jmm.0.009662-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In this study, we investigated the anti-inflammatory and reinforcing barrier effects of Lactobacillus casei subsp. rhamnosus (Lcr35) on Caco-2 intestinal epithelial cells already exposed to Salmonella LPS. Using the Transwell co-culture model, Salmonella LPS was apically added to polarized Caco-2 cells co-cultured with peripheral blood mononuclear cells (PBMCs) in the basolateral compartment. LPS-stimulated Caco-2 cells were incubated with Lcr35 for 1, 6, 24 or 48 h. Apical inoculation of Lcr35 after 48 h significantly inhibited the basolateral secretion of interleukin-8 (IL-8) in the Caco-2/PBMC co-culture. The PCR analysis showed that Lcr35 significantly downregulated mRNA expression of monocyte chemoattractant protein 1 (MCP-1) (P<0.05) and had a trend of decreasing mRNA expression of IL-8 (P=0.05), but did not alter mRNA expression of transforming growth factor-beta1 in LPS-stimulated Caco-2 cells at 48 h after addition of Lcr35. Compared to non-LPS-pretreated controls, transepithelial electrical resistance (TEER) of the polarized Caco-2 cell monolayers pretreated with LPS for 48 h was decreased by 9.9 % (P<0.05). Additionally, compared to those cells only treated with LPS, apical co-incubation with Lcr35 showed biphasic TEER levels increased by 12.1 % (P<0.001), 5.7 % (P<0.05) and 86.8 % (P<0.001) in the Caco-2 cell monolayers compared to those without Lcr35 treatment after 1, 6 and 48 h, respectively. In conclusion, Lcr35 can exert anti-inflammatory effects and ameliorate barrier dysfunction in the Salmonella LPS-pretreated inflamed intestinal epithelium in vitro.
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Affiliation(s)
- Hsu-Wei Fang
- Division of Medical Engineering Research, National Health Research Institutes, Miaoli, Taiwan, ROC.,Department of Chemical Engineering and Biotechnology, National Taipei University Technology, Taipei, Taiwan, ROC
| | - Shiuh-Bin Fang
- Centre for Paediatric Gastroenterology, Royal Free Campus, University College London Medical School, London, UK
| | | | - Chun-Yan Yeung
- Mackay Medicine, Nursing and Management College, Taipei, Taiwan, ROC.,Department of Paediatrics, Mackay Memorial Hospital, Taipei, Taiwan, ROC
| | - Wai-Tao Chan
- Department of Paediatrics, Mackay Memorial Hospital, Taipei, Taiwan, ROC
| | - Chuen-Bin Jiang
- Department of Paediatrics, Mackay Memorial Hospital, Taipei, Taiwan, ROC
| | - Mei-Lien Cheng
- Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan, ROC
| | - Hung-Chang Lee
- Department of Paediatrics, Taipei Medical University, Taipei, Taiwan, ROC.,Department of Paediatrics, Mackay Memorial Hospital, Taipei, Taiwan, ROC
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12
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Th2 responses elicited by nasal epithelial cells exposed to house dust mite extract. Clin Exp Otorhinolaryngol 2009; 2:175-80. [PMID: 20072691 PMCID: PMC2804092 DOI: 10.3342/ceo.2009.2.4.175] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Accepted: 09/16/2009] [Indexed: 11/14/2022] Open
Abstract
Objectives Respiratory epithelial cells are the first site of interaction of allergens with the immune system. The aim of this study was to examine the effect of epithelial cells, which were stimulated with house dust mite (HDM) extracts, on the immune response of peripheral blood mononuclear cells (PBMCs). Methods Primary nasal polyp epithelial cells were exposed to dermatophagoides pteronyssinus and dermatophagoides farina for 48 hr, and then the supernatant and cells were collected. After stimulation with HDM extract, the epithelial cells were co-cultured with PBMCs for 72 hr and then the supernatant was collected. We measured the interleukin (IL)-8 and granulocyte-macrophage colony stimulating factor to determine the activation of the epithelial cells. The tumor necrosis factor (TNF)-α, IL-5 and interferon-γ were measured to evaluate the interaction between the epithelial cells and the PBMCs. The mRNA expression of intercellular adhesion molecule 1 (ICAM-1) was assessed using the anti-ICAM-1 antibody. Results The HDM extracts activated the nasal epithelial cells and enhanced the expression of ICAM-1 mRNA and cell membrane ICAM-1. When the activated epithelial cells were co-cultured with PBMCs, the PBMCs produced lager amounts of TNF-α and IL-5. However the cytokine production was not inhibited by pretreatment with ICAM-1 antibody. Conclusion HDM allergens induce allergic inflammation by activating nasal epithelial cells, yet the interaction of the epitheila cells and the PBMCs may not be associated with an ICAM-1 medicated mechanism.
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Abstract
The epithelial lining of the gastrointestinal tract is the major interface between the external world (e.g., the gut lumen) and the body, and as such the proper maintenance and regulation of epithelial barrier function is a key determinant of digestive health and host well-being. Many enteropathies are associated with increased gut permeability, including inflammatory bowel disease (IBD). Maintaining the barrier function of the epithelium, independent of whether paracellular or transcellular permeation pathways are considered, is an energy-dependent process. Here we present an overview of the impact that metabolic stress (e.g., reductions in epithelial ATP synthesis) can have on permeability characteristics of epithelial monolayers and show that metabolic stress in the presence of a commensal flora results in a significant loss of epithelial integrity, and that this increase in epithelial permeability can be enhanced by the presence of tumor necrosis factor-alpha (TNFalpha). We speculate that the combination of these factors in vivo would result in significant perturbations in epithelial barrier function that could be of pathophysiological significance and contribute to the initiation of IBD or the induction of disease relapses.
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Affiliation(s)
- Kimberley Lewis
- Department of Physiology and Biophysics, University of Calgary, Calgary, Alberta, Canada
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14
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Lewis K, Caldwell J, Phan V, Prescott D, Nazli A, Wang A, Soderhölm JD, Perdue MH, Sherman PM, McKay DM. Decreased epithelial barrier function evoked by exposure to metabolic stress and nonpathogenic E. coli is enhanced by TNF-alpha. Am J Physiol Gastrointest Liver Physiol 2008; 294:G669-78. [PMID: 18187519 DOI: 10.1152/ajpgi.00382.2007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A defect in mitochondrial activity contributes to many diseases. We have shown that monolayers of the human colonic T84 epithelial cell line exposed to dinitrophenol (DNP, uncouples oxidative phosphorylation) and nonpathogenic Escherichia coli (E. coli) (strain HB101) display decreased barrier function. Here the impact of DNP on macrophage activity and the effect of TNF-alpha, DNP, and E. coli on epithelial permeability were assessed. DNP treatment of the human THP-1 macrophage cell line resulted in reduced ATP synthesis, and, although hyporesponsive to LPS, the metabolically stressed macrophages produced IL-1beta, IL-6, and TNF-alpha. Given the role of TNF-alpha in inflammatory bowel disease (IBD) and the association between increased permeability and IBD, recombinant TNF-alpha (10 ng/ml) was added to the DNP (0.1 mM) + E. coli (10(6) colony-forming units), and this resulted in a significantly greater loss of T84 epithelial barrier function than that elicited by DNP + E. coli. This increased epithelial permeability was not due to epithelial death, and the enhanced E. coli translocation was reduced by pharmacological inhibitors of NF-kappabeta signaling (pyrrolidine dithiocarbamate, NF-kappabeta essential modifier-binding peptide, BAY 11-7082, and the proteosome inhibitor, MG132). In contrast, the drop in transepithelial electrical resistance was unaffected by the inhibitors of NF-kappabeta. Thus, as an integrative model system, our findings support the induction of a positive feedback loop that can severely impair epithelial barrier function and, as such, could contribute to existing inflammation or trigger relapses in IBD. Thus metabolically stressed epithelia display increased permeability in the presence of viable nonpathogenic E. coli that is exaggerated by TNF-alpha released by activated immune cells, such as macrophages, that retain this ability even if they themselves are experiencing a degree of metabolic stress.
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Affiliation(s)
- Kimberley Lewis
- Gastrointestinal Research Group, Department of Physiology and Biophysics, University of Calgary, Calgary, Alberta, Canada
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15
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Hirota CL, McKay DM. Cholinergic regulation of epithelial ion transport in the mammalian intestine. Br J Pharmacol 2006; 149:463-79. [PMID: 16981004 PMCID: PMC2014671 DOI: 10.1038/sj.bjp.0706889] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Acetylcholine (ACh) is critical in controlling epithelial ion transport and hence water movements for gut hydration. Here we review the mechanism of cholinergic control of epithelial ion transport across the mammalian intestine. The cholinergic nervous system affects basal ion flux and can evoke increased active ion transport events. Most studies rely on measuring increases in short-circuit current (ISC = active ion transport) evoked by adding ACh or cholinomimetics to intestinal tissue mounted in Ussing chambers. Despite subtle species and gut regional differences, most data indicate that, under normal circumstances, the effect of ACh on intestinal ion transport is mainly an increase in Cl- secretion due to interaction with epithelial M3 muscarinic ACh receptors (mAChRs) and, to a lesser extent, neuronal M1 mAChRs; however, AChR pharmacology has been plagued by a lack of good receptor subtype-selective compounds. Mice lacking M3 mAChRs display intact cholinergically-mediated intestinal ion transport, suggesting a possible compensatory mechanism. Inflamed tissues often display perturbations in the enteric cholinergic system and reduced intestinal ion transport responses to cholinomimetics. The mechanism(s) underlying this hyporesponsiveness are not fully defined. Inflammation-evoked loss of mAChR-mediated control of epithelial ion transport in the mouse reveals a role for neuronal nicotinic AChRs, representing a hitherto unappreciated braking system to limit ACh-evoked Cl- secretion. We suggest that: i) pharmacological analyses should be supported by the use of more selective compounds and supplemented with molecular biology techniques targeting specific ACh receptors and signalling molecules, and ii) assessment of ion transport in normal tissue must be complemented with investigations of tissues from patients or animals with intestinal disease to reveal control mechanisms that may go undetected by focusing on healthy tissue only.
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Affiliation(s)
- C L Hirota
- Department Physiology & Biophysics, University of Calgary, Calgary, AB, Canada.
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16
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Kammanadiminti SJ, Chadee K. Suppression of NF-κB Activation by Entamoeba histolytica in Intestinal Epithelial Cells Is Mediated by Heat Shock Protein 27. J Biol Chem 2006; 281:26112-20. [PMID: 16840786 DOI: 10.1074/jbc.m601988200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Little is known about the pathogenesis of Entamoeba histolytica and how epithelial cells respond to the parasite. Herein, we characterized the interactions between E. histolytica and colonic epithelial cells and the role macrophages play in modulating epithelial cell responses. The human colonic epithelial cell lines Caco-2 and T84 were grown either as monoculture or co-cultured in transwell plates with differentiated human THP-1 macrophages for 24 h before stimulation with soluble amebic proteins (SAP). In naive epithelial cells, prolonged stimulation with SAP reduced the levels of heat shock protein (Hsp) 27 and 72. However in THP-1 conditioned intestinal epithelial cells SAP enhanced Hsp27 and Hsp72, which was dependent on the activation of ERK MAP kinase. Hsp synthesis induced by SAP conferred protection against oxidative and apoptotic injuries. Treatment with SAP inhibited NF-kappaB activation induced by interleukin-1beta; specifically, the NF-kappaB-DNA binding, nuclear translocation of p65 subunit, and phosphorylation of IkappaB-alpha were reduced. Gene silencing by small interfering RNA confirmed the role of Hsp27 in suppressing NF-kappaB activation at IkappaB kinase (IKK) level. By co-immunoprecipitation studies, we found that Hsp27 interacts with IKK-alpha and IKK-beta, and this association was increased in SAP-treated conditioned epithelial cells. Overexpression of wild type Hsp27 amplified the effects of SAP, whereas a phosphorylation-deficient mutant of Hsp27 abrogated SAP-induced NF-kappaB inhibition. In conditioned epithelial cells, Hsp27 was phosphorylated at serine 15 after prolonged exposure to SAP. This mechanism may explain the absence of colonic inflammation seen in the majority of individuals infected with E. histolytica.
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Affiliation(s)
- Srinivas J Kammanadiminti
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta T2N 4N1, Canada
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17
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Watson JL, Ansari S, Cameron H, Wang A, Akhtar M, McKay DM. Green tea polyphenol (-)-epigallocatechin gallate blocks epithelial barrier dysfunction provoked by IFN-gamma but not by IL-4. Am J Physiol Gastrointest Liver Physiol 2004; 287:G954-61. [PMID: 15231486 DOI: 10.1152/ajpgi.00302.2003] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A characteristic of many enteropathies is increased epithelial permeability, a potentially pathophysiological event that can be evoked by T helper (Th)-1 (i.e., IFN-gamma) and Th2 (i.e., IL-4) cytokines and bacterial infection [e.g., enteropathogenic Escherichia coli (EPEC)]. The green tea polyphenol (-)-epigallocatechin gallate (EGCG) has immunosuppressive properties, and we hypothesized that it would ameliorate the increased epithelial permeability induced by IFN-gamma, IL-4, and/or EPEC. EGCG, but not the related epigallocatechin, completely prevented the increase in epithelial (i.e., T84 cell monolayer) permeability caused by IFN-gamma exposure as gauged by transepithelial resistance and horseradish peroxidase flux; EGCG did not alleviate the barrier disruption induced by IL-4 or EPEC. IFN-gamma-treated T84 and THP-1 (monocytic cell line) cells displayed STAT1 activation (tyrosine phosphorylation on Western blot analysis, DNA binding on EMSA) and upregulation of interferon response factor-1 mRNA, a STAT1-dependent gene. All three events were inhibited by EGCG pretreatment. Aurintricarboxylic acid also blocked IFN-gamma-induced STAT1 activation, but it did not prevent the increase in epithelial permeability. Additionally, pharmacological blockade of MAPK signaling did not affect IFN-gamma-induced epithelial barrier dysfunction. Thus, as a potential adjunct anti-inflammatory agent, EGCG can block STAT1-dependent events in gut epithelia and monocytes and prevent IFN-gamma-induced increased epithelial permeability. The latter event is both a STAT1- and MAPK-independent event.
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Affiliation(s)
- James L Watson
- Intestinal Disease Research Programme, Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, L8N 3Z5, Canada
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18
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Abstract
PURPOSE OF REVIEW T cells are central to most inflammatory disorders of the intestine, particularly Celiac disease, graft vs. host disease, Crohn disease, and ulcerative colitis. The mechanisms by which T cells contribute to mucosal damage in these disorders have been explored using both in vitro and in vivo models. This review will highlight recent studies directed at understanding the mechanisms by which T cells are involved in the induction of mucosal damage. RECENT FINDINGS The recent studies of in vivo T-cell activation using monoclonal anti-CD3 antibody have shown that a number of cytotoxic T-cell pathways are required and involved in the induction of mucosal damage and in particular in the induction of epithelial cell apoptosis. These include the Fas/FasL and perforin pathways. Other mediators of T-cell-induced cytotoxicity, such as TNFalpha and IFNgamma may contribute to mucosal damage but are not required for the induction of mucosal damage in vivo. In addition, several studies have tried to identify the role of regulatory mucosal T cells and the physiologically relevant triggers for T-cell-induced mucosal damage. SUMMARY It is now clear that there are significant redundancies in the mechanisms that lead to immune-mediated mucosal damage and that the mechanisms that operate in vivo may not be predicted by in vitro experiments. These investigations are improving our understanding of the pathogenesis of immune-mediated enteropathies and will hopefully lead to new approaches to the management of these disorders.
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Affiliation(s)
- Kenneth Croitoru
- Intestinal Diseases Research Program, Division of Gastroenterology, McMaster University, Hamilton, Ontario, Canada.
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19
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Howe KL, Wang A, Hunter MM, Stanton BA, McKay DM. TGFbeta down-regulation of the CFTR: a means to limit epithelial chloride secretion. Exp Cell Res 2004; 298:473-84. [PMID: 15265695 DOI: 10.1016/j.yexcr.2004.04.026] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2003] [Revised: 04/13/2004] [Indexed: 11/22/2022]
Abstract
Transforming growth factor beta (TGFbeta) is a multifunctional cytokine with effects on many cell types. We recently showed that in addition to epithelial barrier enhancing properties, TGFbeta causes diminished cAMP-driven chloride secretion in colonic epithelia, in a manner that is p38 MAPK-dependent. In this study, we sought to further delineate the mechanism behind TGFbeta diminution of chloride secretion. Using colonic and kidney epithelial cell lines, we found that exposure to TGFbeta causes dramatic changes in the expression and localization of the apical membrane chloride channel, cystic fibrosis transmembrane conductance regulator (CFTR). In TGFbeta-treated colonic epithelia (T84 and HT-29), CFTR mRNA was significantly reduced 2-24 h post-cytokine exposure. At a time consistent with decreased colonic epithelial secretory responses (16 h), TGFbeta treatment caused diminished intracellular CFTR protein expression (confocal microscopy) and reduced channel expression in the apical membrane during stimulated chloride secretion (biotinylation assay). In comparison, polarized kidney epithelia (MDCK) treated with TGFbeta displayed similarly reduced secretory responses to cAMP stimulating agents; however, a perinuclear accumulation of CFTR was observed, contrasting the diffuse cytoplasmic CFTR expression of control cells. Our data indicate that TGFbeta has profound effects on the expression and subcellular localization of an important channel involved in cAMP-driven chloride secretion, and thus suggest TGFbeta represents a key regulator of fluid movement.
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Affiliation(s)
- Kathryn L Howe
- Intestinal Disease Research Programme, Department of Pathology and Molecular Medicine, McMaster University, HSC-3N5C, Hamilton, Ontario, Canada L8N 3Z5
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20
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Affiliation(s)
- M Sawkat Anwer
- Department of Biomedical Sciences, Tufts University School of Veterinary Medicine, 200 Westboro Road, N. Grafton, MA 01536, USA.
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21
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Nazli A, Yang PC, Jury J, Howe K, Watson JL, Söderholm JD, Sherman PM, Perdue MH, McKay DM. Epithelia under metabolic stress perceive commensal bacteria as a threat. THE AMERICAN JOURNAL OF PATHOLOGY 2004; 164:947-57. [PMID: 14982848 PMCID: PMC1614709 DOI: 10.1016/s0002-9440(10)63182-3] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/19/2003] [Indexed: 12/12/2022]
Abstract
The normal gut flora has been implicated in the pathophysiology of inflammatory bowel disease and there is increased interest in the role that stress can play in gut disease. The chemical stressor dinitrophenol (DNP, uncouples oxidative phosphorylation) was injected into the ileum of laparotomized rats and mitochondria structure, epithelial permeability, and inflammatory cell infiltrate were examined 6 and 24 hours later. Monolayers of human colonic epithelial cells (T84, HT-29) were treated with DNP +/- commensal Escherichia coli, followed by assessment of epithelial permeability, bacterial translocation, and chemokine (ie, interleukin-8) synthesis. Delivery of DNP into rat distal ileum resulted in disruption of epithelial mitochondria; similar changes were noted in mildly inflamed ileal resections from patients with Crohn's disease. Also, DNP-treated ileum displayed increased gut permeability and immune cell recruitment. Subsequent studies revealed deceased barrier function, increased bacterial translocation, increased production of interleukin-8, and enhanced mobilization of the transcription factor AP-1 in the model epithelial cell lines exposed to commensal bacteria (E. coli strains HB101 or C25), but only when the monolayers were pretreated with DNP (0.1 mmol/L). These data suggest that enteric epithelia under metabolic stress perceive a normally innocuous bacterium as threatening, resulting in loss of barrier function, increased penetration of bacteria into the mucosa, and increased chemokine synthesis. Such responses could precipitate an inflammatory episode and contribute to existing enteric inflammatory disorders.
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Affiliation(s)
- Aisha Nazli
- Intestinal Disease Research Programme, McMaster University, Hamilton, Ontario, Canada
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22
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Akhtar M, Watson JL, Nazli A, McKay DM. Bacterial DNA evokes epithelial IL‐8 production by a MAPK‐dependent, NFκB‐independent pathway. FASEB J 2003. [DOI: 10.1096/fj.02-0950fje] [Citation(s) in RCA: 126] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Mahmood Akhtar
- Intestinal Disease Research Programme, Department of Pathology and Molecular MedicineMcMaster University Hamilton Ontario Canada
| | - James L. Watson
- Intestinal Disease Research Programme, Department of Pathology and Molecular MedicineMcMaster University Hamilton Ontario Canada
| | - Aisha Nazli
- Intestinal Disease Research Programme, Department of Pathology and Molecular MedicineMcMaster University Hamilton Ontario Canada
| | - Derek M. McKay
- Intestinal Disease Research Programme, Department of Pathology and Molecular MedicineMcMaster University Hamilton Ontario Canada
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Yang H, Finaly R, Teitelbaum DH. Alteration in epithelial permeability and ion transport in a mouse model of total parenteral nutrition. Crit Care Med 2003; 31:1118-25. [PMID: 12682482 DOI: 10.1097/01.ccm.0000053523.73064.8a] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE To investigate the effects of total parenteral nutrition administration on intestinal ion transport and intestinal epithelial permeability. Additionally, to assess the role of interferon-gamma on the total parenteral nutrition-induced loss of epithelial barrier function. DESIGN Randomized, controlled study. SETTING Experimental laboratory, University of Michigan Medical School, Ann Arbor. SUBJECTS Adult wild-type and interferon-gamma knockout mice. INTERVENTIONS Wild-type mice received total parenteral nutrition or enteral diet (control group) for 7 days. Segments of small bowel from the mice were mounted in Ussing chambers. Short circuit current, as an indictor of active ion transport, was constantly monitored. Epithelial barrier function was assessed by measuring transepithelial resistance and transmural passage of 51Cr-EDTA and 3H-mannitol. Intestinal intraepithelial lymphocyte-derived interferon-gamma protein expression was detected with enzyme-linked immunosorbent assay and confirmed by using intracellular staining and flow cytometry. To investigate the effect of total parenteral nutrition on intestinal ion transport, we used a secretory agonist, carbachol, and an absorptive agent, glucose. MEASUREMENTS AND MAIN RESULTS Total parenteral nutrition significantly increased small-bowel permeability. Ion transport in the total parenteral nutrition group was significantly increased. To stimulate ion transport, we found that increases in short circuit current induced by carbachol and glucose were higher in the total parenteral nutrition group compared with the control group. Intestinal intraepithelial lymphocyte interferon-gamma protein expression significantly increased with the administration of total parenteral nutrition. Intestinal permeability in interferon-gamma knockout total parenteral nutrition mice was significantly lower than in wild-type mice receiving total parenteral nutrition. CONCLUSION Total parenteral nutrition has significant effects on intestinal epithelial physiology, stimulating ion secretion and reducing epithelial barrier function. Interferon-gamma appears to play an important role in the loss of the epithelial barrier function that is associated with total parenteral nutrition.
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Affiliation(s)
- Hua Yang
- Section of Pediatric Surgery, University of Michigan Hospitals, Mott F3970, Box 0245, Ann Arbor, MI 48109, USA
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24
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Howe K, Gauldie J, McKay DM. TGF-beta effects on epithelial ion transport and barrier: reduced Cl- secretion blocked by a p38 MAPK inhibitor. Am J Physiol Cell Physiol 2002; 283:C1667-74. [PMID: 12388073 DOI: 10.1152/ajpcell.00414.2001] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Growth factors affect a variety of epithelial functions. We examined the ability of TGF-beta to modulate epithelial ion transport and permeability. Filter-grown monolayers of human colonic epithelia, T84 and HT-29 cells, were treated with TGF-beta (0.1-100 ng/ml, 15 min-72 h) or infected with an adenoviral vector encoding TGF-beta (Ad-TGF beta) for 144 h. Ion transport (i.e., short-circuit current, I(sc)) and transepithelial resistance (TER) were assessed in Ussing chambers. Neither recombinant TGF-beta nor Ad-TGF beta infection affected baseline I(sc); however, exposure to > or = 1 ng/ml TGF-beta led to a significant (30-50%) reduction in the I(sc) responses to forskolin, vasoactive intestinal peptide, and cholera toxin (agents that evoke Cl(-) secretion via cAMP mobilization) and to the cell-permeant dibutyryl cAMP. Pharmacological analysis of signaling pathways revealed that the inhibition of cAMP-driven epithelial Cl(-) secretion by TGF-beta was blocked by pretreatment with SB-203580, a specific inhibitor of p38 MAPK, but not by inhibitors of JNK, ERK1/2 MAPK, or phosphatidylinositol 3'-kinase. TGF-beta enhanced the barrier function of the treated monolayers by up to threefold as assessed by TER; however, this event was temporally displaced from the altered I(sc) response, being statistically significant only at 72 h posttreatment. Thus, in addition to TGF-beta promotion of epithelial barrier function, we show that this growth factor also reduces responsiveness to cAMP-dependent secretagogues in a chronic manner and speculate that this serves as a braking mechanism to limit secretory enteropathies.
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Affiliation(s)
- Kathryn Howe
- Intestinal Disease Research Program, Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada L8N 3Z5
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Yang H, Kiristioglu I, Fan Y, Forbush B, Bishop DK, Antony PA, Zhou H, Teitelbaum DH. Interferon-gamma expression by intraepithelial lymphocytes results in a loss of epithelial barrier function in a mouse model of total parenteral nutrition. Ann Surg 2002; 236:226-34. [PMID: 12170028 PMCID: PMC1422569 DOI: 10.1097/00000658-200208000-00011] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To determine the etiology of the loss of epithelial barrier function observed with the administration of total parenteral nutrition (TPN) in a mouse model. SUMMARY BACKGROUND DATA Removal of enteral nutrition with the administration of TPN is associated with a loss of intestinal epithelial barrier function. The etiology of this barrier loss is not clear. Because intraepithelial lymphocytes (IELs) produce a number of cytokines that may alter epithelial permeability, the authors investigated IEL cytokine expression in a mouse model of TPN. METHODS Adult C57BL/6 mice received TPN or enteral diet for 7 days. IELs were subsequently harvested and the mRNA expression of cytokines was measured. Epithelial barrier function was assessed in vitro with 51Cr-EDTA in Ussing chambers and was expressed as the permeability coefficient (Papp). RESULTS IEL mRNA expression of interferon-gamma (IFN-gamma) rose from 0.14 +/- 0.07 in the control (enterally fed) group to 0.44 +/- 0.11 attomoles/microL in the TPN group (P <.05). Transforming growth factor-beta1 declined slightly but not significantly, from 0.75 +/- 0.35 to 0.55 +/- 0.18 attomoles/microL in the control and TPN groups, respectively. Epithelial barrier function declined significantly with TPN compared to controls. To assess the relevance of IFN-gamma changes, permeability in IFN-gamma knockout mice was studied. Barrier function was significantly higher in IFN-gamma knockout mice on TPN compared to C57BL/6 mice that received TPN. CONCLUSIONS IEL cytokine expression changes significantly with TPN administration. The partial correction with IFN-gamma knockout mice suggests that an upregulation of IFN-gamma expression is one mechanism responsible for the loss of the epithelial barrier associated with TPN.
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Affiliation(s)
- Hua Yang
- Section of Pediatric Surgery, The University of Michigan Medical School and C. S. Mott Children's Hospital, Ann Arbor, Michigan, USA
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26
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Rachlis A, Watson JL, Lu J, McKay DM. Nitric oxide reduces bacterial superantigen‐immune cell activation and consequent epithelial abnormalities. J Leukoc Biol 2002. [DOI: 10.1189/jlb.72.2.339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Alisa Rachlis
- Intestinal Disease Research Programme, McMaster University, Hamilton, Ontario, Canada
| | - James L. Watson
- Intestinal Disease Research Programme, McMaster University, Hamilton, Ontario, Canada
| | - Jun Lu
- Intestinal Disease Research Programme, McMaster University, Hamilton, Ontario, Canada
| | - Derek M. McKay
- Intestinal Disease Research Programme, McMaster University, Hamilton, Ontario, Canada
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27
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Black JL, Johnson PRA. Factors controlling smooth muscle proliferation and airway remodelling. Curr Opin Allergy Clin Immunol 2002; 2:47-51. [PMID: 11964750 DOI: 10.1097/00130832-200202000-00008] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
It is clear that airway smooth muscle plays an important role in the hyperresponsiveness and remodelling that occur in the asthmatic airway. This is by virtue of its roles as a contractile cell, a cell that undergoes proliferation as part of the inflammatory response, a cell that actively participates in the inflammatory response via the production of cytokines and chemokines, and perhaps as a cell that undergoes migration. Now that airway smooth muscle cells cultured from asthmatic patients have been studied in vitro, it is apparent that there is an abnormality in the growth of these cells such that they grow more rapidly than cells derived from nonasthmatic patients. This raises the possibility of identifying the exact point(s) in the signal transduction pathways at which this abnormality occurs. To do this it is necessary to define precisely the mitogenic pathways that lead to proliferation in the airway smooth muscle cell, and this information is accumulating rapidly. The possibility is raised for new therapeutic targets that are aimed specifically at the airway smooth muscle, leading to an effective method for reversing or preventing the airway remodelling that accompanies chronic severe asthma.
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Affiliation(s)
- Judith L Black
- Department of Pharmacology, University of Sydney, New South Wales, Australia 2006.
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28
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Abstract
Human peripheral blood CD8+ T cells comprise cells that are in different states of differentiation and under the control of complex homeostatic processes. In a number of situations ranging from chronic inflammatory conditions and infectious diseases to ageing, immunodeficiency, iron overload and heavy alcohol intake, major phenotypic changes, usually associated with an increase in CD8+ T cells lacking CD28 expression, take place. CD8+CD28- T cells are characterized by a low proliferative capacity to conventional stimulation in vitro and by morphological and functional features of activated/memory T cells. Although the nature of the signals that give origin to this T-cell subset is uncertain, growing evidence argues for the existence of an interplay between epithelial cells, molecules with the MHC-class I fold and CD8+ T cells. The possibility that the generation of CD8+CD28- T cells is the combination of TCR/CD3zeta- and regulatory factor-mediated signals as a result of the sensing of modifications of the internal environment is discussed.
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Affiliation(s)
- Fernando A Arosa
- Laboratory of Molecular Immunology, Institute for Molecular and Cell Biology (IBMC) and Molecular Immunology and Pathology, Abel Salazar Institute for the Biomedical Sciences(ICBAS), Porto, Portugal.
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29
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Oprins JC, van der Burg C, Meijer HP, Munnik T, Groot JA. PLD pathway involved in carbachol-induced Cl- secretion: possible role of TNF-alpha. Am J Physiol Cell Physiol 2001; 280:C789-95. [PMID: 11245595 DOI: 10.1152/ajpcell.2001.280.4.c789] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In a previous study, it was found that exposure to tumor necrosis factor-alpha (TNF-alpha) potentiated the electrophysiological response to carbachol in a time-dependent and cycloheximide-sensitive manner. It was deduced that the potentiation could be due to protein kinase C activity because of increased 1,2-diacylglycerol. It was also observed that propranolol could decrease the electrophysiological response to carbachol (Oprins JC, Meijer HP, and Groot JA. Am J Physiol Cell Physiol 278: C463-C472, 2000). The aim of the present study was to investigate whether the phospholipase D (PLD) pathway plays a role in the carbachol response and the potentiating effect of TNF-alpha. The transphosphatidylation reaction in the presence of the primary alcohol 1-butanol [leading to stable phosphatidylbutanol (Pbut) formation] was used to measure activity of PLD. The phosphatidic acid (PA) levels were also measured. Muscarinic stimulation resulted in an increased formation of Pbut and PA. TNF-alpha decreased levels of PA.
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Affiliation(s)
- J C Oprins
- Swammerdam Institute for Life Sciences, University of Amsterdam, P.O. Box 94084, 1090 GB Amsterdam, The Netherlands.
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Zareie M, Singh PK, Irvine EJ, Sherman PM, McKay DM, Perdue MH. Monocyte/macrophage activation by normal bacteria and bacterial products: implications for altered epithelial function in Crohn's disease. THE AMERICAN JOURNAL OF PATHOLOGY 2001; 158:1101-9. [PMID: 11238058 PMCID: PMC1850371 DOI: 10.1016/s0002-9440(10)64057-6] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Intestinal immune cells are less reactive than those in the peripheral blood; however, such cells from patients with Crohn's disease may be more responsive to bacterial products. Our study examined if nonpathogenic bacteria or lipopolysaccharide (LPS), can affect epithelial function in the presence of monocytes/macrophages. Lamina propria mononuclear cells (LPMCs) and peripheral blood monocytes (PBMs) were obtained from patients with Crohn's disease and control patients. Filter-grown T84 epithelial monolayers were co-cultured with nonactivated or LPS-activated LPMCs or PBMs for 48 hours. Epithelial secretory [baseline short-circuit current (Isc) and DeltaIsc to forskolin] and barrier (transepithelial electrical resistance) parameters were measured in Ussing chambers. LPS-activated PBMs from both controls and patients with Crohn's disease significantly increased Isc ( approximately 300%) and reduced transepithelial electrical resistance ( approximately 40%). Epithelial function was not altered after co-culture with control LPMCs +/- LPS. However, LPMCs from patients with Crohn's disease spontaneously secreted tumor necrosis factor-alpha, and induced epithelial changes similar to those produced by LPS-activated PBMs. Co-culture with control Escherichia coli and PBMs induced comparable changes in epithelial physiology, which were abrogated by anti-tumor necrosis factor-alpha antibody. We conclude that LPMCs of patients with Crohn's disease are spontaneously activated, possibly by gram-negative luminal bacteria, and can directly cause significant alterations in epithelial ion transport and barrier functions.
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Affiliation(s)
- M Zareie
- Intestinal Disease Research Program, McMaster University, 1200 Main St. West, Hamilton, Ontario, L8N 3Z5, Canada
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31
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Gitter AH, Bendfeldt K, Schmitz H, Schulzke JD, Bentzel CJ, Fromm M. Epithelial barrier defects in HT-29/B6 colonic cell monolayers induced by tumor necrosis factor-alpha. Ann N Y Acad Sci 2001; 915:193-203. [PMID: 11193576 DOI: 10.1111/j.1749-6632.2000.tb05242.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The barrier function of intestinal epithelia relies upon the continuity of the enterocyte monolayer and intact tight junctions. After incubation with tumor necrosis factor-alpha TNF-alpha, however, the number of strands that form the tight junctions decreases, and apoptosis is induced in intestinal epithelial cells. These morphological changes lead to a rise of transepithelial ion permeability, because the paracellular ion permeability increases and leaks associated with sites of apoptosis increase by number and magnitude. Thus apoptosis and degradation of tight junctions contribute to the increased permeability observed after exposure to TNF-alpha. These mechanisms explain clinical manifestations in the inflamed intestinal wall containing cytokine-secreting macrophages--for example, leak flux diarrhea and invasion of bacterial enterotoxins.
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Affiliation(s)
- A H Gitter
- Institut für Klinische Physiologie, Universitätsklinikum Benjamin Franklin, Freie Universität Berlin, 12200 Berlin, Germany.
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32
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Abstract
There is increasing evidence supporting the involvement of immune cells and mediators in the control of intestinal physiology. Cell coculture systems and epithelial cell lines have provided convenient model systems for the study of immunomodulation of epithelial function. Abundant cytokines and immune mediators have been shown to directly or indirectly alter epithelial transport of ions and macromolecules. Animal models of hypersensitivity have shown that luminal antigen challenge in the intestine of sensitized rats induces a rapid ion secretory response due to enhanced transepithelial transport of antigen. Transport of ions and macromolecules is highly regulated and an important component of host defense. Dysregulation of epithelial function may play a role in several intestinal disorders, such as inflammatory bowel diseases and food allergy.
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Affiliation(s)
- L C Yu
- Intestinal Disease Research Program, Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario L6J3X6, Canada
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33
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Yang PC, Berin MC, Yu L, Perdue MH. Mucosal pathophysiology and inflammatory changes in the late phase of the intestinal allergic reaction in the rat. THE AMERICAN JOURNAL OF PATHOLOGY 2001; 158:681-90. [PMID: 11159205 PMCID: PMC1850309 DOI: 10.1016/s0002-9440(10)64010-2] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Relatively little information exists concerning the late phase of the allergic reaction in the gastrointestinal tract. Here, we characterized jejunal mucosal pathophysiology and inflammation after oral antigen challenge of sensitized rats, and examined the role of mast cells in events after challenge. Sprague-Dawley rats, mast cell-deficient (Ws/Ws), and +/+ control rats were sensitized to horseradish peroxidase, and challenged intragastrically with antigen 14 days later. Jejunal segments were obtained at 0.5 to 72 hours after challenge for functional assessment in Ussing chambers and for morphological assessment by light and electron microscopy. Intestine from sensitized Sprague-Dawley rats demonstrated enhanced ion secretion and permeability at all times after challenge. Electron microscopy revealed abnormal mitochondria within enterocytes and disruption of the epithelial basement membrane associated with influx into the mucosa of mast cells, eosinophils, neutrophils, and mononuclear cells. Many inflammatory cells appeared activated. In contrast, antigen-challenged Ws/Ws rats demonstrated no functional changes or inflammatory cell infiltrate. We conclude that oral antigen challenge of sensitized rats induces sustained epithelial dysfunction. Mast cells mediate both epithelial pathophysiology and recruitment of additional inflammatory cells that may contribute to persistent pathophysiology and symptoms.
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Affiliation(s)
- P C Yang
- Intestinal Disease Research Program, McMaster University, Hamilton, Ontario, Canada
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34
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Bisping G, Lügering N, Lütke-Brintrup S, Pauels HG, Schürmann G, Domschke W, Kucharzik T. Patients with inflammatory bowel disease (IBD) reveal increased induction capacity of intracellular interferon-gamma (IFN-gamma) in peripheral CD8+ lymphocytes co-cultured with intestinal epithelial cells. Clin Exp Immunol 2001; 123:15-22. [PMID: 11167992 PMCID: PMC1905965 DOI: 10.1046/j.1365-2249.2001.01443.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Intestinal epithelial cells seem to play a key role during IBD. The network of cellular interactions between epithelial cells and lamina propria mononuclear cells is still incompletely understood. In the following co-culture model we investigated the influence of intestinal epithelial cells on cytokine expression of T cytotoxic and T helper cells from patients with IBD and healthy controls. Peripheral blood mononuclear cells (PBMC) were purified by a Ficoll-Hypaque gradient followed by co-incubation with epithelial cells in multiwell cell culture insert plates in direct contact as well as separated by transwell filters. We used Caco-2 cells as well as freshly isolated colonic epithelia obtained from surgical specimens. Three-colour immunofluorescence flow cytometry was performed after collection, stimulation and staining of PBMC with anti-CD4, anti-CD8, anti-IFN-gamma and anti-IL-4. Patients with IBD (Crohn's disease (CD), n = 12; ulcerative colitis (UC), n = 16) and healthy controls (n = 10) were included in the study. After 24 h of co-incubation with Caco-2 cells we found a significant increase of IFN-gamma-producing CD8+ lymphocytes in patients with IBD. In contrast, healthy controls did not respond to the epithelial stimulus. No significant differences could be found between CD and UC or active and inactive disease. A significant increase of IFN-gamma+/CD8+ lymphocytes in patients with UC was also seen after direct co-incubation with primary cultures of colonic crypt cells. The observed epithelial-lymphocyte interaction seems to be MHC I-restricted. No significant epithelial cell-mediated effects on cytokine expression were detected in the PBMC CD4+ subsets. Patients with IBD-even in an inactive state of disease-exert an increased capacity for IFN-gamma induction in CD8+ lymphocytes mediated by intestinal epithelial cells. This mechanism may be important during chronic intestinal inflammation, as in the case of altered mucosal barrier function epithelial cells may become targets for IFN-gamma-producing CD8+ lymphocytes.
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Affiliation(s)
- G Bisping
- Department of Medicine B, Department of General Surgery and Institute of Immunology, University of Münster, Münster, Germany
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35
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Oprins JC, Meijer HP, Groot JA. TNF-alpha potentiates the ion secretion induced by muscarinic receptor activation in HT29cl.19A cells. Am J Physiol Cell Physiol 2000; 278:C463-72. [PMID: 10712234 DOI: 10.1152/ajpcell.2000.278.3.c463] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Chronic gastrointestinal diseases such as ulcerative colitis and Crohn's disease are characterized by severe diarrhea. Mucosal biopsies of these patients show enhanced levels of cytokines, secreted by infiltrated inflammatory cells. In this study, we investigated the effect of the cytokine tumor necrosis factor-alpha (TNF-alpha) on ion secretion in human intestinal epithelial cells. The conventional microelectrode technique in the cell line HT29cl. 19A was used, which allows for simultaneous measurements of transepithelial potential difference and intracellular potential difference across the apical membrane. Preincubation (2-78 h) with 10 ng/ml TNF-alpha did not change basal secretory activity. However, the secretory response to the muscarinic receptor agonist carbachol was strongly increased after exposure to TNF-alpha. Application of the protein kinase C (PKC) inhibitor GF 109203X (bisindolylmaleimide I) inhibited the response to carbachol as well as the TNF-alpha-potentiated response, indicating that PKC mediates the effect of carbachol in this cell line. Propranolol, a substance that inhibits the phospholipase D (PLD) pathway, strongly reduced the response to muscarinic stimulation and its potentiation by TNF-alpha. The results indicate that activation of PLD is involved in ion secretion induced by muscarinic receptor activation and that TNF-alpha can potentiate this pathway.
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Affiliation(s)
- J C Oprins
- Institute for Neurobiology, Biological Faculty, University of Amsterdam, 1098 SM Amsterdam, The Netherlands.
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36
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Mägert HJ, Hill O, Zucht HD, Martin S, Meyer M, Forssmann WG, Adermann K. Porcine guanylin and uroguanylin: cDNA sequences, deduced amino acid sequences, and biological activity of the chemically synthesized peptides. Biochem Biophys Res Commun 1999; 259:141-8. [PMID: 10334930 DOI: 10.1006/bbrc.1999.0719] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Guanylin and uroguanylin are structurally related intestinal peptide hormones which were purified from a limited number of mammals and are capable of activating the particulate guanylate cyclase-C. Although the biological functions of guanylin and uroguanylin are not yet clarified in detail, they are involved in the regulation of the intestinal water and electrolyte balance. In order to verify the general importance of this hormone system in mammals, we cloned the corresponding cDNAs from pig. Here, we present the nucleotide sequences and the deduced amino acid sequences representing porcine guanylin and uroguanylin. The expression patterns of the corresponding genes, as shown by Northern hybridization and RT-PCR analysis, resemble those of the human homologues. Further, we demonstrate the bioactivity of both porcine peptide hormones by inducing the intracellular cGMP production in human T84 cells and by ion transport experiments using porcine intestinal mucosa in the Ussing chamber.
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Affiliation(s)
- H J Mägert
- Lower Saxony Institute for Peptide Research (IPF), Feodor-Lynen-Strasse 31, Hannover, D-30625, Germany
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37
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Abstract
Determination of plasma and tissue cytokine levels in inflammatory bowel disease have frequently resulted in conflicting data. In the present study we determined in patients with ulcerative colitis (UC), the levels of the proinflammatory cytokines interleukin (IL)-1beta, IL-6, interferon (IFN)-gamma, and tumor-necrosis factor (TNF)-alpha liberated by peripheral blood mononuclear cells (PBMC) and lamina propria mononuclear cells (LPMC) after 48-hr culture with pokeweed mitogen (PWM). IL-1beta, IL-6, IFN-gamma and TNF-alpha in the supernatant were detected by ELISA. Results show low basal levels of IL-1beta secretion by PBMC and LPMC, and a considerable increase after mitogen stimulation. Basal IL-6 production by PBMC was higher in UC patients than in controls [2029 pg/ml, CI95(-165 to 4223) vs 572 pg/ml (-383 to 1527) respectively, P = 0.05] and also after PWM activation [14,995 pg/ml (7759-22,230) vs 6598 pg/ml (3240-9956), respectively, P = 0.05]. In LPMC, no differences in IL-6 secretion were observed. TNF-alpha in activated PBMC of patients with UC was not significantly increased in relation to control (P = 0.09). No constitutive secretion of IFN-gamma was observed in mononuclear cells. IFN-gamma levels secreted by activated LPMC were lower in patients with UC than in controls [1571 pg/ml (-108 to 3251) vs 7953 pg/ml (3851-12,055), respectively, P = 0.03]. These results suggest that IL-6, IL-1beta, and TNF-alpha participate as mediators in the inflammatory phenomena observed in UC. Further studies are necessary to evaluate the role of IFN-gamma in this condition.
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38
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Hill CE. The anion transport inhibitor DIDS activates a Ba2+-sensitive K+ flux associated with hepatic exocrine secretion. Can J Physiol Pharmacol 1999. [DOI: 10.1139/y99-025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
4,4'-Diisothiocyanatostilbene-2,2'-disulfonate (DIDS), an anion transport inhibitor and choleretic organic anion, was used to study the relationship between putative DIDS-sensitive K channels and exocrine secretion in the isolated and bile duct cannulated perfused rat liver. Bile flow, DIDS excretion, and effluent perfusate K+ content were measured. DIDS (125 µM) caused a doubling in bile generation concomitant with its appearance in bile, confirming earlier reports. Furthermore, DIDS induced a transient increase in perfusate K+ concentration that peaked prior to the biliary parameters and, after 10 min, reversed to net uptake that fully compensated for the initial release. The K channel blocker Ba2+ (1 mM) strongly inhibited the release phase along with the accompanying choleresis and DIDS excretion. Ouabain (13.5 µM) alone was choleretic and hyperkalemic and, when applied in combination with DIDS, depressed DIDS excretion, choleresis, and DIDS-sensitive K+ uptake. To obtain further evidence for the presence of DIDS-sensitive K channels K+ flux was measured under the influence of different gradients of the cation. Perfusate K+ at 26 and 80 mM changed the DIDS-activated K+ flux from a transient outward to a sustained inward flux, and both DIDS excretion and bile flow decreased. Mean net K+ flux over 20 min DIDS perfusion changed from -1.3 ± 1.1 µmol/g with 5.9 mM K+ to -1304 ± 55 µmol/g with 80 mM K+ in the perfusate. K+ efflux was fully and reversibly blocked by Ba2+ and influx was ouabain-insensitive, suggesting that the DIDS-activated K+ flux was channel mediated. The results show that a significant fraction of DIDS-induced bile generation is associated with K+ release that may be mediated by Ba2+-sensitive K channels, possibly of the inward rectifying type.Key words: hepatocyte, inward rectifier, 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (DIDS), K+ channel, bile formation.
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39
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Radojevic N, McKay DM, Merger M, Vallance BA, Collins SM, Croitoru K. Characterization of enteric functional changes evoked by in vivo anti-CD3 T cell activation. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:R715-23. [PMID: 10070131 DOI: 10.1152/ajpregu.1999.276.3.r715] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Specific in vivo T cell activation initiated by treatment with anti-CD3 antibodies leads to diarrhea and structural damage of the intestinal mucosa. In this study, the effect of T cell-induced mucosal damage on jejunal epithelial ion transport, muscle contractility, and neuronal ACh release was assessed in Ussing chambers, organ baths, and a specialized perfusion apparatus, respectively. Time-matched control mice received hamster serum containing irrelevant antibodies. Jejunal segments from anti-CD3-treated mice displayed a significantly elevated epithelial baseline short-circuit current (which indicates increased ion transport) and a concomitant reduction in responsiveness to prosecretory stimuli (nerve stimulation, carbachol, and forskolin). Longitudinal smooth muscle displayed altered spontaneous contractile activity, length-tension relationships, and carbachol-stimulated contraction in tissues excised from mice 20 and 40 h posttreatment. Anti-CD3 treatment did not affect stimulated ACh release from myenteric plexus neurons. We conclude that specific T cell activation via anti-CD3 antibody results in dramatic alterations in jejunal epithelial and smooth muscle function. Such T cell-induced changes in intestinal function may contribute to the symptomatology of T cell-mediated enteropathies, including graft-versus-host disease, celiac disease, and idiopathic inflammatory bowel disease.
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Affiliation(s)
- N Radojevic
- Intestinal Disease Research Programme, McMaster University, Hamilton, Ontario, Canada L8N 3Z5
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40
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Trauner M, Mennone A, Gigliozzi A, Fraioli F, Boyer JL. Nitric oxide and guanosine 3',5'-cyclic monophosphate stimulate bile secretion in isolated rat hepatocyte couplets, but not in isolated bile duct units. Hepatology 1998; 28:1621-8. [PMID: 9828227 DOI: 10.1002/hep.510280623] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Nitric oxide (NO) and guanosine 3',5'-cyclic monophosphate (cGMP) have recently been shown to stimulate bile acid-independent bile flow in the isolated perfused rat liver (IPRL). However, the cellular origin and mechanisms of this choleresis have not yet been determined. To address these questions, we examined the effects of NO and cGMP on bile secretion in isolated rat hepatocyte couplets (IRHC) and in isolated bile duct units (IBDU), both of which are isolated cell systems in which cell polarity is maintained and secretion can be measured directly. Changes in the area of the canalicular and ductular lumens were determined in IRHC and IBDU, respectively, as indicators of the rate of fluid secretion using video microscopy. In addition, Cl-/HCO3- exchanger activity in IBDU was evaluated by measuring changes in intracellular pH (pHi) after Cl- removal/readmission by microfluorometric methods. In the presence of HCO3-, both the NO donor, S-nitroso-acetyl-penicillamine (SNAP), and the cell-permeant cGMP analogue, dibutyryl cGMP (DBcGMP), stimulated canalicular bile secretion (P <.05), as did the cell-permeant cAMP analogue, dibutyryl cAMP (DBcAMP) (P <.05). Removal of HCO3- from the buffer completely abolished the choleretic effects of DBcGMP, but had no effect on NO-induced choleresis. In contrast, secretion in IBDU was not stimulated following incubations with SNAP or DBcGMP over 30 minutes, whereas DBcAMP and secretin, a cholangiocyte secretagogue and cAMP agonist, both had a marked effect on ductular secretion over this same time interval (P <.05). SNAP also had no effect on Cl-/HCO3- exchanger activity in IBDU, and inhibition of endogenous NO synthesis by NG-monomethyl-L-arginine (L-NMMA) did not alter secretin-induced stimulation of ductular bile secretion and Cl-/HCO3- exchanger activity. In summary, NO and cGMP stimulate bile secretion exclusively at the the level of hepatocytes, whereas cAMP mediates choleresis at both hepatocyte and bile duct levels. These findings may have important implications for the regulation of ductular bile secretion by hormones and neuropeptides, as well as under pathological conditions with increased hepatic NO synthesis.
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Affiliation(s)
- M Trauner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Karl Franzens University School of Medicine, Graz, Austria
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41
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Kiliaan AJ, Saunders PR, Bijlsma PB, Berin MC, Taminiau JA, Groot JA, Perdue MH. Stress stimulates transepithelial macromolecular uptake in rat jejunum. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 275:G1037-44. [PMID: 9815034 DOI: 10.1152/ajpgi.1998.275.5.g1037] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Evidence suggests that stress may be a contributing factor in intestinal inflammatory disease; however, the involved mechanisms have not been elucidated. We previously reported that acute stress alters epithelial physiology of rat intestine. In this study, we documented stress-induced macromolecular transport across intestinal epithelium. After exposure of Wistar-Kyoto rats to acute restraint stress, transport of a model protein, horseradish peroxidase (HRP), was assessed in isolated segments of jejunum. The flux of intact HRP was significantly enhanced across intestine from stressed rats compared with controls. Electron microscopy revealed HRP-containing endosomes within enterocytes, goblet cells, and Paneth cells of stressed rats. The number and area of HRP endosomes within enterocytes were found to be significantly increased by stress. HRP was also visualized in paracellular spaces between adjacent epithelial cells only in intestine from stressed rats. Atropine treatment of rats prevented the stress-induced abnormalities of protein transport. Our results suggest that stress, via a mechanism that involves release of acetylcholine, causes epithelial dysfunction that includes enhanced uptake of macromolecular protein antigens. We speculate that immune reactions to such foreign proteins may initiate or exacerbate inflammation.
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Affiliation(s)
- A J Kiliaan
- Intestinal Disease Research Program, Faculty of Health Sciences, McMaster University, Hamilton, Ontario, Canada L8N 3Z5
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42
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Zareie M, McKay DM, Kovarik GG, Perdue MH. Monocyte/macrophages evoke epithelial dysfunction: indirect role of tumor necrosis factor-alpha. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 275:C932-9. [PMID: 9755046 DOI: 10.1152/ajpcell.1998.275.4.c932] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We examined the ability of monocytes (MPhi) activated by bacterial products to alter epithelial physiology. Confluent monolayers of the T84 colonic epithelial cell line were grown on filter supports and then cocultured in the presence of human MPhi with or without the activating agents bacterial lipopolysaccharide and the bacterial tripeptide formyl-methionyl-leucyl-phenylalanine. After 24 or 48 h, monolayers were mounted in Ussing chambers where parameters of epithelial function were measured. Exposure to activated MPhi resulted in a significant increase (P < 0.05) in baseline short-circuit current (250% after 48 h) that was associated with enhanced secretion of Cl-. In addition, epithelial permeability was significantly increased as shown by reduced transepithelial resistance and increased flux of 51Cr-EDTA. Activated MPhi produced substantial amounts (approximately 3 ng/ml at 48 h) of tumor necrosis factor-alpha (TNF-alpha). TNF-alpha was identified as a key mediator acting via an autocrine mechanism to induce epithelial pathophysiology. Our data show that MPhi, when activated by common bacterial components, are potent effector cells capable of initiating significant changes in the transport and barrier properties of a model epithelium.
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Affiliation(s)
- M Zareie
- Intestinal Disease Research Program, McMaster University, Hamilton, Ontario, Canada L8N 3Z5
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43
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McKay DM, Benjamin MA, Lu J. CD4+ T cells mediate superantigen-induced abnormalities in murine jejunal ion transport. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 275:G29-38. [PMID: 9655681 DOI: 10.1152/ajpgi.1998.275.1.g29] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The immunomodulatory properties of bacterial superantigens (SAgs) have been defined, yet comparatively little is known of how SAgs may affect enteric physiology. Staphylococcus aureus enterotoxin B (SEB) was used to examine the ability of SAgs to alter epithelial ion transport. BALB/c mice, severe combined immunodeficient (SCID, lack T cells) mice, or SCID mice reconstituted with lymphocytes or CD4+ T cells received SEB intraperitoneally, and jejunal segments were examined in Ussing chambers; controls received saline only. Baseline short-circuit current (Isc, indicates net ion transport) and Isc responses evoked by electrical nerve stimulation, histamine, carbachol, or forskolin were recorded. Serum levels of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) were measured. SEB-treated BALB/c mice showed elevated serum IL-2 and IFN-gamma levels, and jejunal segments displayed a time- and dose-dependent increase in baseline Isc compared with controls. Conversely, evoked ion secretion was selectively reduced in jejunum from SEB-treated mice. Elevated cytokine levels and changes in jejunal Isc were not observed in SEB-treated SCID mice. In contrast, SCID mice reconstituted with T cells were responsive to SEB challenge as shown by increased cytokine production and altered jejunal Isc responses that were similar to those observed in jejunum from SEB-treated BALB/c mice. We conclude that exposure to a model bacterial SAg causes distinct changes in epithelial physiology and that these events can be mediated by CD4+ T cells.
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Affiliation(s)
- D M McKay
- Intestinal Disease Research Program, McMaster University, Hamilton, Ontario, Canada L8N 3Z5
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44
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Benjamin MA, Lu J, Donnelly G, Dureja P, McKay DM. Changes in murine jejunal morphology evoked by the bacterial superantigen Staphylococcus aureus enterotoxin B are mediated by CD4+ T cells. Infect Immun 1998; 66:2193-9. [PMID: 9573107 PMCID: PMC108181 DOI: 10.1128/iai.66.5.2193-2199.1998] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Bacterial superantigens (SAgs) are potent T-cell stimuli that have been implicated in the pathophysiology of autoimmune and inflammatory disease. We used Staphylococcus aureus enterotoxin B (SEB) as a model SAg to assess the effects of SAg exposure on gut form and cellularity. BALB/c, SCID (lacking T cells) and T-cell-reconstituted SCID mice were treated with SEB (5 or 100 microg intraperitoneally), and segments of the mid-jejunum were removed 4, 12, or 48 h later and processed for histochemical or immunocytochemical analysis of gut morphology and major histocompatibility complex class II (MHC II) expression and the enumeration of CD3+ T cells and goblet cells. Control mice received saline only. SEB treatment of BALB/c mice caused a time- and dose-dependent enteropathy that was characterized by reduced villus height, increased crypt depth, and a significant increase in MHC II expression. An increase in the number of CD3+ T cells was observed 48 h after exposure to 100 microg of SEB. Enteric structural alterations were not apparent in SEB-treated SCID mice compared to saline-treated SCID mice. In contrast, SEB challenge of SCID mice reconstituted with a mixed lymphocyte population or purified murine CD4+ T cells resulted in enteric histopathological changes reminiscent of those observed in SEB-treated BALB/c mice. These findings implicate CD4+ T cells in this SEB-induced enteropathy. Our results show that SAg immune activation causes significant changes in jejunal villus-crypt architecture and cellularity that are likely to impact on normal physiological processes. We speculate that the elevated MHC II expression and increased number of T cells could allow for enhanced immune responsiveness to other SAgs or environmental antigens.
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Affiliation(s)
- M A Benjamin
- Intestinal Disease Research Programme, McMaster University, Hamilton, Ontario, Canada
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45
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Arosa FA, Irwin C, Mayer L, de Sousa M, Posnett DN. Interactions between peripheral blood CD8 T lymphocytes and intestinal epithelial cells (iEC). Clin Exp Immunol 1998; 112:226-36. [PMID: 9649184 PMCID: PMC1904972 DOI: 10.1046/j.1365-2249.1998.00566.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Intestinal intraepithelial lymphocytes (iIEL) are primarily CD8 cells and most of them have a CD28- phenotype, the phenotype of effector cytotoxic T cells. We asked whether the predominance of CD8+CD28- T cells in the gut may result from peripheral blood T cells preferentially migrating to the iIEL compartment and adhering to iEC. Compared with CD4 cells, adhesion of resting CD8+ T cells to iEC cell lines was significantly higher. Adhesion could be blocked with a MoAb to gp180, a molecule expressed on iEC which is known to interact with CD8/lck. No significant difference in the level of adhesion was observed between CD8+CD28+ and CD8+CD28- T cells. Thus CD8 cells may preferentially migrate to the iIEL compartment, but loss of CD28 expression could occur in situ after migration. Consistent with this hypothesis, the CD8+CD28- cells became enriched after co-culturing T cells with iEC cell lines and primary iEC. Induction of the CD8+CD28- phenotype in cord blood and adult T cells was observed in co-cultures with iEC and also with mitogens and superantigens. In the latter case, CD28 down-modulation was seen specifically in the Vbeta subset targeted by the superantigen, indicating that loss of CD28 expression is a direct result of T cell receptor (TCR)-mediated stimulation. The combined results suggest that CD8+CD28- T cells are antigen experienced T cells, and that they may have a survival advantage in the presence of gut epithelial cells in vitro. This may contribute to the predominance of CD8+CD28- T cells in the iIEL compartment.
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Affiliation(s)
- F A Arosa
- Department of Molecular Immunology, Abel Salazar Institute for the Biomedical Sciences, University of Porto, Portugal
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Shiomi M, Wakabayashi Y, Sano T, Shinoda Y, Nimura Y, Ishimura Y, Suematsu M. Nitric oxide suppression reversibly attenuates mitochondrial dysfunction and cholestasis in endotoxemic rat liver. Hepatology 1998; 27:108-15. [PMID: 9425925 DOI: 10.1002/hep.510270118] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This study aimed to examine whether nitric oxide (NO) plays a causal role in endotoxin-induced dysfunction of biliary transport. Rats were treated with intraperitoneal injection of endotoxin (O111B4, 4 mg/kg). At 2 hours, the liver was excised and perfused ex vivo with taurocholate (TC)-containing Krebs-Ringer solution under monitoring bile output and NO2 in the perfusate and tissue cyclic guanosine monophosphate (cGMP) levels as indices of NO production. The endotoxin treatment evoked a marked decrease in the bile acid-dependent bile formation concurrent with the increasing NO2 output, cGMP elevation, and a reduction of hepatic adenosine triphosphate (ATP) contents and oxygen consumption. Perfusion with 1 mmol/L aminoguanidine (AG), an inhibitor of inducible NO synthase, but not with L-nitroarginine methyl ester, an inhibitor of the constitutive form of the enzyme, significantly reversed the endotoxin-induced increment of the bile formation in concert with the recovery of oxygen consumption and ATP levels. Laser confocal microfluorography of the liver lobules using rhodamine 123 (Rh), a fluoroprobe sensitive to mitochondrial membrane potential, revealed that endotoxin elicited a significant mitochondrial dysfunction panlobularly. The AG administration reversed the endotoxin-induced decrease in mitochondrial membrane potential. Collectively, up-regulation of NO by inducible NO synthase accounts for a mechanism through which endotoxin impairs the bile formation, and its suppression serves as a therapeutic strategy for improvement of hepatobiliary function.
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Affiliation(s)
- M Shiomi
- First Department of Surgery, Nagoya University School of Medicine, Japan
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McKay DM, Philpott DJ, Perdue MH. Review article: In vitro models in inflammatory bowel disease research--a critical review. Aliment Pharmacol Ther 1997; 11 Suppl 3:70-80. [PMID: 9467981 DOI: 10.1111/j.1365-2036.1997.tb00811.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Research efforts in inflammatory bowel disease (IBD) have been directed towards the epithelium as it has become clear that epithelial cells play a critical role in inflammatory response. Most research involving IBD employs in vitro techniques. In vitro epithelial cell studies have played and are continuing to play a major role in providing specific information relevant to IBD. Thus, such studies have provided irrefutable evidence that epithelial responses can be induced by microbes/microbial products and by immune activation. Culture experiments have provided insights into the effects of individual cytokines and other inflammatory mediators on epithelial pathophysiology, injury and repair, apoptosis, necrosis, and other processes that may be involved in IBD. Activated epithelial cells can participate in and even orchestrate immune responses, by stimulating T cells (and possibly others) and by producing cytokines that recruit specific inflammatory cells. Physiological regulation of epithelial tight junctions has been demonstrated by in vitro studies; the implication of this information for treating IBD is just beginning to be explored. It is becoming increasingly clear that epithelial processing and presentation of antigens is critical to the outcome of the immune response.
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Affiliation(s)
- D M McKay
- Intestinal Disease Research Programme, McMaster University, Hamilton, Ontario, Canada
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