151
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Paini M, Crippa S, Partelli S, Scopelliti F, Tamburrino D, Baldoni A, Falconi M. Molecular pathology of intraductal papillary mucinous neoplasms of the pancreas. World J Gastroenterol 2014; 20:10008-10023. [PMID: 25110429 PMCID: PMC4123331 DOI: 10.3748/wjg.v20.i29.10008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 04/09/2014] [Indexed: 02/06/2023] Open
Abstract
Since the first description of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas in the eighties, their identification has dramatically increased in the last decades, hand to hand with the improvements in diagnostic imaging and sampling techniques for the study of pancreatic diseases. However, the heterogeneity of IPMNs and their malignant potential make difficult the management of these lesions. The objective of this review is to identify the molecular characteristics of IPMNs in order to recognize potential markers for the discrimination of more aggressive IPMNs requiring surgical resection from benign IPMNs that could be observed. We briefly summarize recent research findings on the genetics and epigenetics of intraductal papillary mucinous neoplasms, identifying some genes, molecular mechanisms and cellular signaling pathways correlated to the pathogenesis of IPMNs and their progression to malignancy. The knowledge of molecular biology of IPMNs has impressively developed over the last few years. A great amount of genes functioning as oncogenes or tumor suppressor genes have been identified, in pancreatic juice or in blood or in the samples from the pancreatic resections, but further researches are required to use these informations for clinical intent, in order to better define the natural history of these diseases and to improve their management.
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MESH Headings
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/metabolism
- Carcinoma, Pancreatic Ductal/classification
- Carcinoma, Pancreatic Ductal/genetics
- Carcinoma, Pancreatic Ductal/metabolism
- Carcinoma, Pancreatic Ductal/pathology
- Carcinoma, Papillary/classification
- Carcinoma, Papillary/genetics
- Carcinoma, Papillary/metabolism
- Carcinoma, Papillary/pathology
- DNA Methylation
- Epigenesis, Genetic
- Gene Expression Regulation, Neoplastic
- Genetic Predisposition to Disease
- Genetic Testing
- Humans
- Neoplasms, Cystic, Mucinous, and Serous/classification
- Neoplasms, Cystic, Mucinous, and Serous/genetics
- Neoplasms, Cystic, Mucinous, and Serous/metabolism
- Neoplasms, Cystic, Mucinous, and Serous/pathology
- Pancreatic Neoplasms/classification
- Pancreatic Neoplasms/genetics
- Pancreatic Neoplasms/metabolism
- Pancreatic Neoplasms/pathology
- Phenotype
- Predictive Value of Tests
- Signal Transduction
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152
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Chen SJ, Liu XW, Liu JP, Yang XY, Lu FG. Ulcerative colitis as a polymicrobial infection characterized by sustained broken mucus barrier. World J Gastroenterol 2014; 20:9468-9475. [PMID: 25071341 PMCID: PMC4110578 DOI: 10.3748/wjg.v20.i28.9468] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Revised: 02/24/2014] [Accepted: 05/05/2014] [Indexed: 02/06/2023] Open
Abstract
To reduce medication for patients with ulcerative colitis (UC), we need to establish the etiology of UC. The intestinal microbiota of patients with inflammatory bowel disease (IBD) has been shown to differ from that of healthy controls and abundant data indicate that it changes in both composition and localization. Small intestinal bacterial overgrowth is significantly higher in IBD patients compared with controls. Probiotics have been investigated for their capacity to reduce the severity of UC. The luminal surfaces of the gastrointestinal tract are covered by a mucus layer. This normally acts as a barrier that does not allow bacteria to reach the epithelial cells and thus limits the direct contact between the host and the bacteria. The mucus layer in the colon comprises an inner layer that is firmly adherent to the intestinal mucosa, and an outer layer that can be washed off with minimal rinsing. Some bacteria can dissolve the protective inner mucus layer. Defects in renewal and formation of the inner mucus layer allow bacteria to reach the epithelium and have implications for the causes of colitis. In this review, important elements of UC pathology are thought to be the intestinal bacteria, gut mucus, and the mucosa-associated immune system.
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153
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Aliakbarpour HR, Chamani M, Rahimi G, Sadeghi AA, Qujeq D. The Bacillus subtilis and Lactic Acid Bacteria Probiotics Influences Intestinal Mucin Gene Expression, Histomorphology and Growth Performance in Broilers. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2014; 25:1285-93. [PMID: 25049692 PMCID: PMC4092943 DOI: 10.5713/ajas.2012.12110] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 06/05/2012] [Accepted: 04/26/2012] [Indexed: 12/21/2022]
Abstract
The aim of the present study was to evaluate the effect of commercial monostrain and multistrain probiotics in diets on growth performance, intestinal morphology and mucin gene (MUC2) expression in broiler chicks. Three hundred seventy-eight 1-d-old male Arian broiler chicks were allocated in 3 experimental groups for 6 wk. The birds were fed on a corn-soybean based diet and depending on the addition were labeled as follows: control-unsupplemented (C), birds supplemented with Bacillus subtilis (BS) and lactic acid bacteria (LAB) based probiotics. Each treatment had 6 replicates of 21 broilers each. Treatment effects on body weight, feed intake, feed conversion ratio and biomarkers such as intestinal goblet cell density, villus length, villus width, and mucin gene expression were determined. Total feed intake did not differ significantly between control birds and those fed a diet with probiotics (p>0.05). However, significant differences in growth performance were found. Final body weight at 42 d of age was higher in birds fed a diet with probiotics compared to those fed a diet without probiotic (p<0.05). Inclusion of Bacillus subtilis based probiotic in the diets also significantly affected feed conversion rate (FCR) compared with control birds (p<0.05). No differences in growth performance were observed in birds fed different types of probiotic supplemented diets. Inclusion of lactic acid bacteria based probiotic in the diets significantly increased goblet cell number and villus length (p<0.05). Furthermore, diets with Bacillus subtilis based probiotics significantly increased gene expression (p<0.05), with higher intestinal MUC2 mRNA in birds fed diet with probiotics compared to those fed the control diet. In BS and LAB probiotic fed chicks, higher growth performance may be related to higher expression of the MUC2 gene in goblet cells and/or morphological change of small intestinal tract. The higher synthesis of the mucin gene after probiotic administration may positively affect bacterial interactions in the intestinal digestive tract, intestinal mucosal cell proliferation and consequently efficient nutrient absorption.
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Affiliation(s)
- H R Aliakbarpour
- Laboratory for Molecular Genetics and Animal Biotechnology, Department of Animal Sciences, Sari Agricultural Sciences and Natural Resources University, Sari, 578-58932, Iran
| | - M Chamani
- Laboratory for Molecular Genetics and Animal Biotechnology, Department of Animal Sciences, Sari Agricultural Sciences and Natural Resources University, Sari, 578-58932, Iran
| | - G Rahimi
- Laboratory for Molecular Genetics and Animal Biotechnology, Department of Animal Sciences, Sari Agricultural Sciences and Natural Resources University, Sari, 578-58932, Iran
| | - A A Sadeghi
- Laboratory for Molecular Genetics and Animal Biotechnology, Department of Animal Sciences, Sari Agricultural Sciences and Natural Resources University, Sari, 578-58932, Iran
| | - D Qujeq
- Department of Biochemistry and Biophysics, Faculty of Medicine, Babol University of Medical Sciences, Babol, 4717647745, Iran
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154
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The Dynamic Interactions between Salmonella and the Microbiota, within the Challenging Niche of the Gastrointestinal Tract. INTERNATIONAL SCHOLARLY RESEARCH NOTICES 2014; 2014:846049. [PMID: 27437481 PMCID: PMC4897363 DOI: 10.1155/2014/846049] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 05/14/2014] [Indexed: 12/25/2022]
Abstract
Understanding how Salmonella species establish successful infections remains a foremost research priority. This gastrointestinal pathogen not only faces the hostile defenses of the host's immune system, but also faces fierce competition from the large and diverse community of microbiota for space and nutrients. Salmonella have solved these challenges ingeniously. To jump-start growth, Salmonella steal hydrogen produced by the gastrointestinal microbiota. Type 3 effector proteins are subsequently secreted by Salmonella to trigger potent inflammatory responses, which generate the alternative terminal electron acceptors tetrathionate and nitrate. Salmonella exclusively utilize these electron acceptors for anaerobic respiration, permitting metabolic access to abundant substrates such as ethanolamine to power growth blooms. Chemotaxis and flagella-mediated motility enable the identification of nutritionally beneficial niches. The resulting growth blooms also promote horizontal gene transfer amongst the resident microbes. Within the gastrointestinal tract there are opportunities for chemical signaling between host cells, the microbiota, and Salmonella. Host produced catecholamines and bacterial autoinducers form components of this chemical dialogue leading to dynamic interactions. Thus, Salmonella have developed remarkable strategies to initially shield against host defenses and to transiently compete against the intestinal microbiota leading to successful infections. However, the immunocompetent host is subsequently able to reestablish control and clear the infection.
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155
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Yassine H, Kamareddine L, Chamat S, Christophides GK, Osta MA. A serine protease homolog negatively regulates TEP1 consumption in systemic infections of the malaria vector Anopheles gambiae. J Innate Immun 2014; 6:806-18. [PMID: 25012124 DOI: 10.1159/000363296] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 04/29/2014] [Indexed: 11/19/2022] Open
Abstract
Clip domain serine protease homologs are widely distributed in insect genomes and play important roles in regulating insect immune responses, yet their exact functions remain poorly understood. Here, we show that CLIPA2, a clip domain serine protease homolog of Anopheles gambiae, regulates the consumption of the mosquito complement-like protein TEP1 during systemic bacterial infections. We provide evidence that CLIPA2 localizes to microbial surfaces in a TEP1-dependent manner whereby it negatively regulates the activity of a putative TEP1 convertase, which converts the full-length TEP1-F form into active TEP1cut. CLIPA2 silencing triggers an exacerbated TEP1-mediated response that significantly enhances mosquito resistance to infections with a broad class of microorganisms including Plasmodium berghei, Escherichia coli and the entomopathogenic fungus Beauveria bassiana. We also provide further evidence for the existence of a functional link between TEP1 and activation of hemolymph prophenoloxidase during systemic infections. Interestingly, the enhanced TEP1-mediated immune response in CLIPA2 knockdown mosquitoes correlated with a significant reduction in fecundity, corroborating the existence of a trade-off between immunity and reproduction. In sum, CLIPA2 is an integral regulatory component of the mosquito complement-like pathway which functions to prevent an overwhelming response by the host in response to systemic infections.
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Affiliation(s)
- Hassan Yassine
- Department of Biology, American University of Beirut, Beirut, Lebanon
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156
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Keeney KM, Yurist-Doutsch S, Arrieta MC, Finlay BB. Effects of antibiotics on human microbiota and subsequent disease. Annu Rev Microbiol 2014; 68:217-35. [PMID: 24995874 DOI: 10.1146/annurev-micro-091313-103456] [Citation(s) in RCA: 184] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Although antibiotics have significantly improved human health and life expectancy, their disruption of the existing microbiota has been linked to significant side effects such as antibiotic-associated diarrhea, pseudomembranous colitis, and increased susceptibility to subsequent disease. By using antibiotics to break colonization resistance against Clostridium, Salmonella, and Citrobacter species, researchers are now exploring mechanisms for microbiota-mediated modulation against pathogenic infection, revealing potential roles for different phyla and family members as well as microbiota-liberated sugars, hormones, and short-chain fatty acids in regulating pathogenicity. Furthermore, connections are now being made between microbiota dysbiosis and a variety of different diseases such as rheumatoid arthritis, inflammatory bowel disease, type 1 diabetes, atopy, and obesity. Future advances in the rapidly developing field of microbial bioinformatics will enable researchers to further characterize the mechanisms of microbiota modulation of disease and potentially identify novel therapeutics against disease.
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157
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Patel S, McCormick BA. Mucosal Inflammatory Response to Salmonella typhimurium Infection. Front Immunol 2014; 5:311. [PMID: 25071772 PMCID: PMC4082011 DOI: 10.3389/fimmu.2014.00311] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 06/20/2014] [Indexed: 12/24/2022] Open
Abstract
The human intestinal epithelium consists of a single layer of epithelial cells that forms a barrier against food antigens and the resident microbiota within the lumen. This delicately balanced organ functions in a highly sophisticated manner to uphold the fidelity of the intestinal epithelium and to eliminate pathogenic microorganisms. On the luminal side, this barrier is fortified by a thick mucus layer, and on the serosal side exists the lamina propria containing a resident population of immune cells. Pathogens that are able to breach this barrier disrupt the healthy epithelial lining by interfering with the regulatory mechanisms that govern the normal balance of intestinal architecture and function. This disruption results in a coordinated innate immune response deployed to eliminate the intruder that includes the release of antimicrobial peptides, activation of pattern-recognition receptors, and recruitment of a variety of immune cells. In the case of Salmonella enterica serovar typhimurium (S. typhimurium) infection, induction of an inflammatory response has been linked to its virulence mechanism, the type III secretion system (T3SS). The T3SS secretes protein effectors that exploit the host’s cell biology to facilitate bacterial entry and intracellular survival, and to modulate the host immune response. As the role of the intestinal epithelium in initiating an immune response has been increasingly realized, this review will highlight recent research that details progress made in understanding mechanisms underlying the mucosal inflammatory response to Salmonella infection, and how such inflammatory responses impact pathogenic fitness of this organism.
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Affiliation(s)
- Samir Patel
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School , Worcester, MA , USA
| | - Beth A McCormick
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School , Worcester, MA , USA
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158
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Wang L, Cao H, Liu L, Wang B, Walker WA, Acra SA, Yan F. Activation of epidermal growth factor receptor mediates mucin production stimulated by p40, a Lactobacillus rhamnosus GG-derived protein. J Biol Chem 2014; 289:20234-44. [PMID: 24895124 DOI: 10.1074/jbc.m114.553800] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The mucus layer coating the gastrointestinal tract serves as the first line of intestinal defense against infection and injury. Probiotics promote mucin production by goblet cells in the intestine. p40, a Lactobacillus rhamnosus GG-derived soluble protein, has been shown to transactivate the EGF receptor (EGFR) in intestinal epithelial cells, which is required for inhibition of apoptosis and preservation of barrier function in the colon, thereby ameliorating intestinal injury and colitis. Because activation of EGFR has been shown to up-regulate mucin production in goblet cells, the purpose of this study was to investigate the effects and mechanisms of p40 regulation of mucin production. p40 activated EGFR and its downstream target, Akt, in a concentration-dependent manner in LS174T cells. p40 stimulated Muc2 gene expression and mucin production in LS174T cells, which were abolished by inhibition of EGFR kinase activity, down-regulation of EGFR expression by EGFR siRNA transfection, or suppression of Akt activation. Treatment with p40 increased mucin production in the colonic epithelium, thus thickening the mucus layer in the colon of wild type, but not of Egfr(wa5) mice, which have a dominant negative mutation in the EGFR kinase domain. Furthermore, inhibition of mucin-type O-linked glycosylation suppressed the effect of p40 on increasing mucin production and protecting intestinal epithelial cells from TNF-induced apoptosis in colon organ culture. Thus, these results suggest that p40-stimulated activation of EGFR mediates up-regulation of mucin production, which may contribute to the mechanisms by which p40 protects the intestinal epithelium from injury.
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Affiliation(s)
- Lihong Wang
- From the Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - Hailong Cao
- the Department of Gastroenterology, Tianjin Medical University General Hospital, Tianjin 300052, China, and
| | - Liping Liu
- From the Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - Bangmao Wang
- the Department of Gastroenterology, Tianjin Medical University General Hospital, Tianjin 300052, China, and
| | - W Allan Walker
- the Mucosal Immunology and Biology Research Center, Massachusetts General Hospital, Harvard University Medical School, Boston, Massachusetts 02114
| | - Sari A Acra
- From the Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - Fang Yan
- From the Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, Vanderbilt University Medical Center, Nashville, Tennessee 37232,
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159
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Loss of Sonic hedgehog leads to alterations in intestinal secretory cell maturation and autophagy. PLoS One 2014; 9:e98751. [PMID: 24887421 PMCID: PMC4041759 DOI: 10.1371/journal.pone.0098751] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 05/07/2014] [Indexed: 12/22/2022] Open
Abstract
Background Intestinal epithelial cells express the Sonic and Indian hedgehog ligands. Despite the strong interest in gut hedgehog signaling in GI diseases, no studies have specifically addressed the singular role of intestinal epithelial cell Sonic hedgehog signaling. The aim of this study was to investigate the specific role of Sonic hedgehog in adult ileal epithelial homeostasis. Methodology/Principal Findings A Sonic hedgehog intestinal epithelial conditional knockout mouse model was generated. Assessment of ileal histological abnormalities, crypt epithelial cell proliferation, epithelial cell fate, junctional proteins, signaling pathways, as well as ultrastructural analysis of intracellular organelles were performed in control and mutant mice. Mice lacking intestinal epithelial Sonic Hedgehog displayed decreased ileal crypt/villus length, decreased crypt proliferation as well as a decrease in the number of ileal mucin-secreting goblet cells and antimicrobial peptide-secreting Paneth cells during adult life. These secretory cells also exhibited disruption of their secretory products in mutant mice. Ultrastructural microscopy analysis revealed a dilated ER lumen in secretory cells. This phenotype was also associated with a decrease in autophagy. Conclusions/Significance Altogether, these findings indicate that the loss of Sonic hedgehog can lead to ileal secretory cell modifications indicative of endoplasmic reticulum stress, accompanied by a significant reduction in autophagy.
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160
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Amini A, Masoumi-Moghaddam S, Ehteda A, Morris DL. Secreted mucins in pseudomyxoma peritonei: pathophysiological significance and potential therapeutic prospects. Orphanet J Rare Dis 2014; 9:71. [PMID: 24886459 PMCID: PMC4013295 DOI: 10.1186/1750-1172-9-71] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 04/22/2014] [Indexed: 12/22/2022] Open
Abstract
Pseudomyxoma peritonei (PMP, ORPHA26790) is a clinical syndrome characterized by progressive dissemination of mucinous tumors and mucinous ascites in the abdomen and pelvis. PMP is a rare disease with an estimated incidence of 1-2 out of a million. Clinically, PMP usually presents with a variety of unspecific signs and symptoms, including abdominal pain and distention, ascites or even bowel obstruction. It is also diagnosed incidentally at surgical or non-surgical investigations of the abdominopelvic viscera. PMP is a neoplastic disease originating from a primary mucinous tumor of the appendix with a distinctive pattern of the peritoneal spread. Computed tomography and histopathology are the most reliable diagnostic modalities. The differential diagnosis of the disease includes secondary peritoneal carcinomatoses and some rare peritoneal conditions. Optimal elimination of mucin and the mucin-secreting tumor comprises the current standard of care for PMP offered in specialized centers as visceral resections and peritonectomy combined with intraperitoneal chemotherapy. This multidisciplinary approach has reportedly provided a median survival rate of 16.3 years, a median progression-free survival rate of 8.2 years and 10- and 15-year survival rates of 63% and 59%, respectively. Despite its indolent, bland nature as a neoplasm, PMP is a debilitating condition that severely impacts quality of life. It tends to be diagnosed at advanced stages and frequently recurs after treatment. Being ignored in research, however, PMP remains a challenging, enigmatic entity. Clinicopathological features of the PMP syndrome and its morbid complications closely correspond with the multifocal distribution of the secreted mucin collections and mucin-secreting implants. Novel strategies are thus required to facilitate macroscopic, as well as microscopic, elimination of mucin and its source as the key components of the disease. In this regard, MUC2, MUC5AC and MUC5B have been found as the secreted mucins of relevance in PMP. Development of mucin-targeted therapies could be a promising avenue for future research which is addressed in this article.
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Affiliation(s)
- Afshin Amini
- Department of Surgery, St George Hospital, The University of New South Wales, Level 3, Clinical Sciences (WR Pitney) Building, Gray Street, Kogarah, Sydney, NSW 2217, Australia
| | - Samar Masoumi-Moghaddam
- Department of Surgery, St George Hospital, The University of New South Wales, Level 3, Clinical Sciences (WR Pitney) Building, Gray Street, Kogarah, Sydney, NSW 2217, Australia
| | - Anahid Ehteda
- Department of Surgery, St George Hospital, The University of New South Wales, Level 3, Clinical Sciences (WR Pitney) Building, Gray Street, Kogarah, Sydney, NSW 2217, Australia
| | - David Lawson Morris
- Department of Surgery, St George Hospital, The University of New South Wales, Level 3, Clinical Sciences (WR Pitney) Building, Gray Street, Kogarah, Sydney, NSW 2217, Australia
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161
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Haq MRU, Kapila R, Saliganti V. Consumption of β-casomorphins-7/5 induce inflammatory immune response in mice gut through Th2 pathway. J Funct Foods 2014. [DOI: 10.1016/j.jff.2014.03.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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162
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Antoni L, Nuding S, Wehkamp J, Stange EF. Intestinal barrier in inflammatory bowel disease. World J Gastroenterol 2014; 20:1165-1179. [PMID: 24574793 PMCID: PMC3921501 DOI: 10.3748/wjg.v20.i5.1165] [Citation(s) in RCA: 265] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 11/08/2013] [Accepted: 12/13/2013] [Indexed: 02/06/2023] Open
Abstract
A complex mucosal barrier protects as the first line of defense the surface of the healthy intestinal tract from adhesion and invasion by luminal microorganisms. In this review, we provide an overview about the major components of this protective system as for example an intact epithelium, the synthesis of various antimicrobial peptides (AMPs) and the formation of the mucus layer. We highlight the crucial importance of their correct functioning for the maintenance of a proper intestinal function and the prevention of dysbiosis and disease. Barrier disturbances including a defective production of AMPs, alterations in thickness or composition of the intestinal mucus layer, alterations of pattern-recognition receptors, defects in the process of autophagy as well as unresolved endoplasmic reticulum stress result in an inadequate host protection and are thought to play a crucial role in the pathogenesis of the inflammatory bowel diseases Crohn’s disease and ulcerative colitis.
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163
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Quach J, St-Pierre J, Chadee K. The future for vaccine development against Entamoeba histolytica. Hum Vaccin Immunother 2014; 10:1514-21. [PMID: 24504133 DOI: 10.4161/hv.27796] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Entamoeba histolytica is the causative agent of amebiasis, one of the top three parasitic causes of mortality worldwide. In the majority of infected individuals, E. histolytica asymptomatically colonizes the large intestine, while in others, the parasite breaches the mucosal epithelial barrier to cause amebic colitis and can disseminate to soft organs to cause abscesses. Vaccinations using native and recombinant forms of the parasite Gal-lectin have been successful in protecting animals against intestinal amebiasis and amebic liver abscess. Protection against amebic liver abscesses has also been reported by targeting other E. histolytica components including the serine-rich protein and the 29-kDa-reductase antigen. To date, vaccines against the Gal-lectin hold the most promise but clinical trials will be required to validate its efficacy in humans. Here, we review the current strategies and future perspectives involved in the development of a vaccine against E. histolytica.
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Affiliation(s)
- Jeanie Quach
- Faculty of Medicine; Department of Microbiology, Immunology, and Infectious Diseases; Snyder Institute for Chronic Diseases; Gastrointestinal Research Group; University of Calgary; Calgary, AB Canada
| | - Joëlle St-Pierre
- Faculty of Medicine; Department of Microbiology, Immunology, and Infectious Diseases; Snyder Institute for Chronic Diseases; Gastrointestinal Research Group; University of Calgary; Calgary, AB Canada
| | - Kris Chadee
- Faculty of Medicine; Department of Microbiology, Immunology, and Infectious Diseases; Snyder Institute for Chronic Diseases; Gastrointestinal Research Group; University of Calgary; Calgary, AB Canada
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164
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Sinnecker H, Krause T, Koelling S, Lautenschläger I, Frey A. The gut wall provides an effective barrier against nanoparticle uptake. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:2092-101. [PMID: 25551037 PMCID: PMC4273221 DOI: 10.3762/bjnano.5.218] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 10/23/2014] [Indexed: 05/21/2023]
Abstract
BACKGROUND The omnipresence of nanoparticles (NPs) in numerous goods has led to a constant risk of exposure and inadvertent uptake for humans. This situation calls for thorough investigation of the consequences of NP intake. As the vast mucosa of the human gastrointestinal tract represents an attractive site of entry, we wanted to take a look on the fate that ingested NPs suffer in the gut. As a model to investigate NP uptake we used the isolated perfused rat small intestine. Differently sized fluorescent latex particles were used as exemplary anthropogenic NPs. RESULTS The particles were administered as bolus into the isolated intestine, and samples from the luminal, vascular and lymphatic compartments were collected over time. NP amounts in the different fluids were determined by fluorescence measurements. No particles could be detected in the vascular and lymphatic system. By contrast a major amount of NPs was found in luminal samples. Yet, a substantial share of particles could not be recovered in the fluid fractions, indicating a sink function of the intestinal tissue for NPs. A histological examination of the gut revealed that virtually no particles adhered to the epithelium or resided in the tissue, the bulk of particles seemed to be trapped in the mucus lining the gut tube. When this mucus was dissolved and removed from the gut almost the entire amount of particles missing could be recovered: over 95% of the given NPs were present in the two fractions, the luminal samples and the dissolved mucus. To foster NP uptake via an extended interaction time with the epithelium, the intestinal peristalsis was decelerated and the duration of the experiment was prolonged. Even under those conditions, no particle fluorescence was detected in the vascular and lymphatic samples. CONCLUSION We could show that after intestinal exposure with a large dose of NPs the vast majority of NPs did obviously not come into contact with the epithelium but was either directly discarded from the gut or trapped in mucus. The healthy small intestinal tract evidently provides an effective barrier against NP uptake whereby the mucus film seems to play an important role.
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Affiliation(s)
- Heike Sinnecker
- Division of Mucosal Immunology & Diagnostics, Priority Program Asthma & Allergy, Research Center Borstel, Leibniz Center for Medicine and Biosciences, Parkallee 22, Borstel, 23845, Germany, Airway Research Center North (ARCN), Member of the German Center for Lung Research
| | - Thorsten Krause
- Division of Mucosal Immunology & Diagnostics, Priority Program Asthma & Allergy, Research Center Borstel, Leibniz Center for Medicine and Biosciences, Parkallee 22, Borstel, 23845, Germany, Airway Research Center North (ARCN), Member of the German Center for Lung Research
| | - Sabine Koelling
- Central Laboratory of Analytical Chemistry, Hamburg University of Technology, Eißendorfer Straße 38, Hamburg, 21073, Germany
| | - Ingmar Lautenschläger
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Schwanenweg 21, Kiel, 24105, Germany
| | - Andreas Frey
- Division of Mucosal Immunology & Diagnostics, Priority Program Asthma & Allergy, Research Center Borstel, Leibniz Center for Medicine and Biosciences, Parkallee 22, Borstel, 23845, Germany, Airway Research Center North (ARCN), Member of the German Center for Lung Research
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Zhao B, Sun L, Zhang W, Wang Y, Zhu J, Zhu X, Yang L, Li C, Zhang Z, Zhang Y. Secretion of intestinal goblet cells: a novel excretion pathway of nanoparticles. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2013; 10:839-49. [PMID: 24183999 DOI: 10.1016/j.nano.2013.10.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 09/01/2013] [Accepted: 10/18/2013] [Indexed: 01/23/2023]
Abstract
UNLABELLED Understanding the excretion pathway is one of the most important prerequisites for the safe use of nanoparticles in biomedicine. However, the excretion of nanoparticles in animals remains largely unknown, except for some particles very small in size. Here we report a novel natural pathway for nanoparticle excretion, the intestinal goblet cell (GC) secretion pathway (IGCSP). Direct live observation of the behavior of 30-200nm activated carbon nanoparticles (ACNP) demonstrated that ACNP microinjected into the yolk sac of zebrafish can be excreted directly through intestinal tract without involving the hepato-biliary (hap-bile) system. Histopathological examination in mice after ligation of the common bile duct (CBD) demonstrated that the intravenously-injected ACNP were excreted into the gut lumen through the secretion of intestinal GCs. ACNP in various secretion phases were revealed by histopathological examination and transmission electron microscopy (TEM). IGCSP, in combination with renal and hap-bile pathways, constitutes a complete nanoparticle excretion mechanism. FROM THE CLINICAL EDITOR Nanoparticle elimination pathways are in the forefront of interest in an effort to optimize and enable nanomedicine applications. This team of authors reports a novel natural pathway for nanoparticle excretion, the intestinal goblet cell (GC) secretion pathway (IGCSP). Direct live observation of the behavior of activated carbon nanoparticles has shown excretion directly through the intestinal tract without involving the hepato-biliary (hap-bile) system in a zebrafish model.
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Affiliation(s)
- Baoquan Zhao
- Institute of Pharmacology and Toxicology and Key Laboratory of Nanopharmacology and NanoToxicology, Beijing Academy of Medical Sciences, Beijing, China
| | - Lan Sun
- Institute of Pharmacology and Toxicology and Key Laboratory of Nanopharmacology and NanoToxicology, Beijing Academy of Medical Sciences, Beijing, China
| | - Wuxu Zhang
- Institute of Pharmacology and Toxicology and Key Laboratory of Nanopharmacology and NanoToxicology, Beijing Academy of Medical Sciences, Beijing, China; School of Pharmacy; and Nanotechnology Research Center for Drugs; Zhengzhou University, Zhengzhou, China
| | - Yuxia Wang
- Institute of Pharmacology and Toxicology and Key Laboratory of Nanopharmacology and NanoToxicology, Beijing Academy of Medical Sciences, Beijing, China
| | - Junjing Zhu
- Hangzhou Hunter Biotechnology Incorporation, Hangzhou, China
| | - Xiaoyu Zhu
- Hangzhou Hunter Biotechnology Incorporation, Hangzhou, China
| | - Liuzhong Yang
- Institute of Pharmacology and Toxicology and Key Laboratory of Nanopharmacology and NanoToxicology, Beijing Academy of Medical Sciences, Beijing, China
| | - Chunqi Li
- Hangzhou Hunter Biotechnology Incorporation, Hangzhou, China
| | - Zhenzhong Zhang
- School of Pharmacy; and Nanotechnology Research Center for Drugs; Zhengzhou University, Zhengzhou, China
| | - Yingge Zhang
- Institute of Pharmacology and Toxicology and Key Laboratory of Nanopharmacology and NanoToxicology, Beijing Academy of Medical Sciences, Beijing, China.
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Ul Haq MR, Kapila R, Sharma R, Saliganti V, Kapila S. Comparative evaluation of cow β-casein variants (A1/A2) consumption on Th2-mediated inflammatory response in mouse gut. Eur J Nutr 2013; 53:1039-49. [PMID: 24166511 DOI: 10.1007/s00394-013-0606-7] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 10/14/2013] [Indexed: 02/07/2023]
Abstract
PURPOSE Recently, apprehension has been raised regarding "A1/A2 hypothesis" suggesting relationship between consumption of A1 "like" variants of cow β-casein and various physiological disorders. The information available is based on either the human epidemiological data of milk consumption or in vitro trials on cell lines with β-casomorphin peptides. The direct scientific evidence establishing the link between consumption of A1/A2 "like" milk and health is scanty. Thus, under present investigation, in vivo trials in mice were undertaken to study the effect of feeding three genetic variants (A1A1, A1A2 and A2A2) of cow β-casein milk on gastrointestinal immune system as it is the first and foremost site of immunological interactions. METHODS Animals were divided into four groups for feeding with basal diet (control) and β-casein isolated from milk of genotyped (A1A1, A1A2 and A2A2) dairy animals, respectively. Gut immune response was analyzed by spectrophotometric assessment of MPO activity, quantitative sandwich ELISA of inflammatory cytokines (MCP-1 and IL-4), antibodies (total IgE, IgG, sIgA, IgG1 and IgG2a) and qRT-PCR of mRNA expression for toll-like receptors (TLR-2 and TLR-4). Histological enumeration of goblet cells, total leukocytes and IgA(+) cells was also carried out. RESULTS It was observed that consumption of A1 "like" variants (A1A1 and A1A2) significantly increased (p < 0.01) the levels of MPO, MCP-1, IL-4, total IgE, IgG, IgG1, IgG2a and leukocyte infiltration in intestine. TLR-2 and TLR-4 mRNA expression was also up-regulated (p < 0.01) on administration of A1 "like" variants. However, no changes in sIgA, IgA(+) and goblet cell numbers were recorded on consumption of any of the β-casein variants. CONCLUSION It is reasonable to conclude that consumption of A1 "like" variants of β-casein induced inflammatory response in gut by activating Th2 pathway as compared to A2A2 variants. The present study thus supports the purported deleterious impacts of consumption of A1 "like" variants of β-casein and suggests possible aggravation of inflammatory response for etiology of various health disorders.
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Affiliation(s)
- Mohammad Raies Ul Haq
- Animal Biochemistry Division, National Dairy Research Institute, Karnal, 132001, Haryana, India,
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167
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Bar-Yoseph F, Lifshitz Y, Cohen T. Review of sn-2 palmitate oil implications for infant health. Prostaglandins Leukot Essent Fatty Acids 2013; 89:139-43. [PMID: 23541258 DOI: 10.1016/j.plefa.2013.03.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Human milk provides the optimal balanced nutrition for the growing infant in the first months after birth. The human mammary gland has evolved with unusual pathways, resulting in a specific positioning of fatty acids at the outer sn-1 and sn-3, and center sn-2 of the triacylglyceride, which is different from the triglycerides in other human tissues and plasma. The development of structured triglycerides enables mimicking the composition as well as structure of human milk fat in infant formulas. Studies conducted two decades ago, together with very recent studies, have provided increasing evidence that this unusual positioning of 16:0 in human milk triglycerides has a significant role for infant health in different directions, such as fat and calcium absorption, bone health, intestinal flora and infant comfort. This review aims to unravel the relevance of human milk triglyceride sn-2 16:0 for intestinal health and inflammatory pathways and for other post-absorption effects.
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168
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Hodges RR, Dartt DA. Tear film mucins: front line defenders of the ocular surface; comparison with airway and gastrointestinal tract mucins. Exp Eye Res 2013; 117:62-78. [PMID: 23954166 DOI: 10.1016/j.exer.2013.07.027] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 07/07/2013] [Accepted: 07/24/2013] [Indexed: 01/09/2023]
Abstract
The ocular surface including the cornea and conjunctiva and its overlying tear film are the first tissues of the eye to interact with the external environment. The tear film is complex containing multiple layers secreted by different glands and tissues. Each layer contains specific molecules and proteins that not only maintain the health of the cells on the ocular surface by providing nourishment and removal of waste products but also protect these cells from environment. A major protective mechanism that the corneal and conjunctival cells have developed is secretion of the innermost layer of the tear film, the mucous layer. Both the cornea and conjunctiva express membrane spanning mucins, whereas the conjunctiva also produces soluble mucins. The mucins present in the tear film serve to maintain the hydration of the ocular surface and to provide lubrication and anti-adhesive properties between the cells of the ocular surface and conjunctiva during the blink. A third function is to contribute to the epithelial barrier to prevent pathogens from binding to the ocular surface. This review will focus on the different types of mucins produced by the corneal and conjunctival epithelia. Also included in this review will be a presentation of the structure of mucins, regulation of mucin production, role of mucins in ocular surface diseases, and the differences in mucin production by the ocular surface, airways and gastrointestinal tract.
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Affiliation(s)
- Robin R Hodges
- Schepens Eye Research Institute/Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, 20 Staniford Street, Boston, MA 02114, USA
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169
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Commensal Clostridia: leading players in the maintenance of gut homeostasis. Gut Pathog 2013; 5:23. [PMID: 23941657 PMCID: PMC3751348 DOI: 10.1186/1757-4749-5-23] [Citation(s) in RCA: 509] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 08/01/2013] [Indexed: 02/08/2023] Open
Abstract
The gastrointestinal tract is a complex and dynamic network where an intricate and mutualistic symbiosis modulates the relationship between the host and the microbiota in order to establish and ensure gut homeostasis. Commensal Clostridia consist of gram-positive, rod-shaped bacteria in the phylum Firmicutes and make up a substantial part of the total bacteria in the gut microbiota. They start to colonize the intestine of breastfed infants during the first month of life and populate a specific region in the intestinal mucosa in close relationship with intestinal cells. This position allows them to participate as crucial factors in modulating physiologic, metabolic and immune processes in the gut during the entire lifespan, by interacting with the other resident microbe populations, but also by providing specific and essential functions. This review focus on what is currently known regarding the role of commensal Clostridia in the maintenance of overall gut function, as well as touch on their potential contribution in the unfavorable alteration of microbiota composition (dysbiosis) that has been implicated in several gastrointestinal disorders. Commensal Clostridia are strongly involved in the maintenance of overall gut function. This leads to important translational implications in regard to the prevention and treatment of dysbiosis, to drug efficacy and toxicity, and to the development of therapies that may modulate the composition of the microflora, capitalizing on the key role of commensal Clostridia, with the end goal of promoting gut health.
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170
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Peatman E, Li C, Peterson BC, Straus DL, Farmer BD, Beck BH. Basal polarization of the mucosal compartment in Flavobacterium columnare susceptible and resistant channel catfish (Ictalurus punctatus). Mol Immunol 2013; 56:317-27. [PMID: 23895942 DOI: 10.1016/j.molimm.2013.04.014] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 04/18/2013] [Accepted: 04/29/2013] [Indexed: 01/30/2023]
Abstract
The freshwater bacterial pathogen, Flavobacterium columnare, infects a variety of ornamental and farmed fish species worldwide through mucosal attachment points on the gill and skin. While previous studies have demonstrated a chemotactic response of F. columnare to fish mucus, little is known about how host gill mucosal molecular and cellular constituents may impact rates of adhesion, tissue invasion, and ultimately, mortality. Here, we describe the use of RNA-seq to profile gill expression differences between channel catfish (Ictalurus punctatus) differing in their susceptibility to F. columnare both basally (before infection) and at three early timepoints post-infection (1 h, 2 h, and 8 h). After sequencing and de novo assembly of over 350 million 100 base-pair transcript reads, between group comparisons revealed 1714 unique genes differentially expressed greater than 1.5-fold at one or more timepoints. In the large dataset, we focused our analysis on basal differential expression between resistant and susceptible catfish as these genes could potentially reveal genetic and/or environmental factors linked with differential rates of infection. A number of critical innate immune components including iNOS2b, lysozyme C, IL-8, and TNF-alpha were constitutively higher in resistant catfish gill, while susceptible fish showed high expression levels of secreted mucin forms, a rhamnose-binding lectin previously linked to susceptibility, and mucosal immune factors such as CD103 and IL-17. Taken together, the immune and mucin profiles obtained by RNA-seq suggest a basal polarization in the gill mucosa, with susceptible fish possessing a putative mucosecretory, toleragenic phenotype which may predispose them to F. columnare infection.
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Affiliation(s)
- Eric Peatman
- Department of Fisheries and Allied Aquacultures, Auburn University, Auburn, AL 36849, USA.
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171
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Lu P, Bar-Yoseph F, Levi L, Lifshitz Y, Witte-Bouma J, de Bruijn ACJM, Korteland-van Male AM, van Goudoever JB, Renes IB. High beta-palmitate fat controls the intestinal inflammatory response and limits intestinal damage in mucin Muc2 deficient mice. PLoS One 2013; 8:e65878. [PMID: 23776564 PMCID: PMC3680492 DOI: 10.1371/journal.pone.0065878] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 04/29/2013] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Palmitic-acid esterified to the sn-1,3 positions of the glycerol backbone (alpha, alpha'-palmitate), the predominant palmitate conformation in regular infant formula fat, is poorly absorbed and might cause abdominal discomfort. In contrast, palmitic-acid esterified to the sn-2 position (beta-palmitate), the main palmitate conformation in human milk fat, is well absorbed. The aim of the present study was to examine the influence of high alpha, alpha'-palmitate fat (HAPF) diet and high beta-palmitate fat (HBPF) diet on colitis development in Muc2 deficient (Muc2(-/-)) mice, a well-described animal model for spontaneous enterocolitis due to the lack of a protective mucus layer. METHODS Muc2(-/-) mice received AIN-93G reference diet, HAPF diet or HBPF diet for 5 weeks after weaning. Clinical symptoms, intestinal morphology and inflammation in the distal colon were analyzed. RESULTS Both HBPF diet and AIN-93G diet limited the extent of intestinal erosions and morphological damage in Muc2(-/-) mice compared with HAPF diet. In addition, the immunosuppressive regulatory T (Treg) cell response as demonstrated by the up-regulation of Foxp3, Tgfb1 and Ebi3 gene expression levels was enhanced by HBPF diet compared with AIN-93G and HAPF diets. HBPF diet also increased the gene expression of Pparg and enzymatic antioxidants (Sod1, Sod3 and Gpx1), genes all reported to be involved in promoting an immunosuppressive Treg cell response and to protect against colitis. CONCLUSIONS This study shows for the first time that HBPF diet limits the intestinal mucosal damage and controls the inflammatory response in Muc2(-/-) mice by inducing an immunosuppressive Treg cell response.
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Affiliation(s)
- Peng Lu
- Division of Neonatology, Department of Pediatrics, Erasmus MC-Sophia, Rotterdam, the Netherlands
- Department of Pediatrics, Emma Children’s Hospital - AMC, Amsterdam, the Netherlands
| | | | | | | | - Janneke Witte-Bouma
- Division of Neonatology, Department of Pediatrics, Erasmus MC-Sophia, Rotterdam, the Netherlands
| | | | | | - Johannes B. van Goudoever
- Department of Pediatrics, Emma Children’s Hospital - AMC, Amsterdam, the Netherlands
- Department of Pediatrics, VU University Medical Center, Amsterdam, the Netherlands
| | - Ingrid B. Renes
- Division of Neonatology, Department of Pediatrics, Erasmus MC-Sophia, Rotterdam, the Netherlands
- Department of Pediatrics, Emma Children’s Hospital - AMC, Amsterdam, the Netherlands
- * E-mail:
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172
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Mucosal barrier in ulcerative colitis and Crohn's disease. Gastroenterol Res Pract 2013; 2013:431231. [PMID: 23737764 PMCID: PMC3664489 DOI: 10.1155/2013/431231] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 04/09/2013] [Indexed: 12/24/2022] Open
Abstract
Background. The mucus layer in the gastrointestinal tract plays important role in host innate defense, regulation of secretion, and absorption processes, maintaining colonization resistance, which composes the integrity of protective mucus barrier in the large intestine. Investigations of mucin expression in the colon mucosa can improve the understanding of protective function of mucosal barrier in ulcerative colitis (UC) and Crohn's disease (CD). Materials and Methods. 77 patients with UC and CD were examined. Histological analysis of colon mucosa was done by standard method (haematoxylin-eosin, alcian blue at pH 1.0 and 2.5 to determine sulfated and nonsulfated glycosaminoglycans and glycoproteins, and goblet cells). To characterize the mucus production the PAS-reaction was performed. Immunohistochemistry was performed using monoclonal mouse antibodies raised against MUC2, MUC3, MUC4, and TFF3 (USBiological, USA). Results. The moderate expression of MUC2 and MUC3 (50.0% and 32.1%, P = 0.03) and high expression of MUC4 and TFF3 in the colon mucosa were observed in all patients with CD. The intensive labeling of MUC4 and TFF3 occurred more often (42.9% and 57.1%, P = 0.03) in patients with CD. The level of expression of secretory MUC2 and transmembrane MUC3 and MUC4 in all patients with UC was low, up to its complete absence (59.2% and 53.1% cases, P = 0.05). TFF3 expression had high and medium staining intensity in patients with UC. Conclusions. Different types of mucins synthesis, secretion, and expression were found in patients with UC and CD. The expression of mucin MUC2, MUC3, MUC4, and TFF3 correlated with the activity of disease and the extent of the inflammatory process in the large intestine. The most pronounced alteration of mucins expression was observed in patients with severe UC and CD.
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Dharmani P, De Simone C, Chadee K. The probiotic mixture VSL#3 accelerates gastric ulcer healing by stimulating vascular endothelial growth factor. PLoS One 2013; 8:e58671. [PMID: 23484048 PMCID: PMC3590171 DOI: 10.1371/journal.pone.0058671] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 02/07/2013] [Indexed: 12/12/2022] Open
Abstract
Studies assessing the effect and mechanism of probiotics on diseases of the upper gastrointestinal tract (GI) including gastric ulcers are limited despite extensive work and promising results of this therapeutic option for other GI diseases. In this study, we investigated the mechanisms by which the probiotic mixture VSL#3 (a mixture of eight probiotic bacteria including Lactobacilli, Bifidobacteria and Streptococcus species) heals acetic acid induced gastric ulcer in rats. VSL#3 was administered orally at low (6×109 bacteria) or high (1.2×1010 bacteria) dosages from day 3 after ulcer induction for 14 consecutive days. VSL#3 treatments significantly enhanced gastric ulcer healing in a dose-dependent manner. To assess the mechanism(s) whereby VSL#3 exerted its protective effects, we quantified the gene expression of several pro-inflammatory cytokines, protein and expression of stomach mucin-Muc5ac, regulatory cytokine-IL-10, COX-2 and various growth factors. Of all the components examined, only expression and protein production of VEGF was increased 332-fold on day 7 in the ulcerated tissues of animals treated with VSL#3. Predictably, animals treated with VEGF neutralizing antibody significantly delayed gastric ulcer healing in VSL#3 treated animals. This is the first report to demonstrate high efficacy of the probiotic mixture VSL#3 in enhancing gastric ulcer healing. Probiotic efficacy was effective at higher concentrations of VSL#3 by specifically increasing the expression and production of angiogenesis promoting growth factors, primarily VEGF.
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Affiliation(s)
- Poonam Dharmani
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Claudio De Simone
- Department of Experimental Medicine, University of L'Aquila, L'Aquila, Italy
| | - Kris Chadee
- Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
- * E-mail:
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174
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Kim JJ, Khan WI. Goblet cells and mucins: role in innate defense in enteric infections. Pathogens 2013; 2:55-70. [PMID: 25436881 PMCID: PMC4235714 DOI: 10.3390/pathogens2010055] [Citation(s) in RCA: 161] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 01/27/2013] [Accepted: 01/28/2013] [Indexed: 12/16/2022] Open
Abstract
Goblet cells reside throughout the gastrointestinal (GI) tract and are responsible for the production and preservation of a protective mucus blanket by synthesizing and secreting high molecular weight glycoproteins known as mucins. The concept of the mucus layer functioning as a dynamic protective barrier is suggested by studies showing changes in mucins in inflammatory conditions of the GI tract, by the altered goblet cell response in germ-free animals, and by the enhanced mucus secretion seen in response to infections. The mucin-containing mucus layer coating the GI epithelium is the front line of innate host defense. Mucins are likely to be the first molecules that invading pathogens interact with at the cell surface and thus, can limit binding to other glycoproteins and neutralize the pathogen. This review will focus on what is known about goblet cell response in various GI infections and the regulatory networks that mediate goblet cell function and mucin production in response to intestinal insults. In addition, we describe the current knowledge on the role of mucins in intestinal innate defense. It is the aim of this review to provide the readers with an update on goblet cell biology and current understanding on the role of mucins in host defense in enteric infections.
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Affiliation(s)
- Janice J Kim
- Farncombe Family Digestive Health Research Institute, McMaster University, 1280 Main St W, Hamilton, Ontario, L8S 4K1, Canada.
| | - Waliul I Khan
- Farncombe Family Digestive Health Research Institute, McMaster University, 1280 Main St W, Hamilton, Ontario, L8S 4K1, Canada.
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175
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Intestinal mucins: the first line of defense. J Clin Gastroenterol 2013; 47:104-5. [PMID: 23314666 DOI: 10.1097/mcg.0b013e3182713185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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176
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Entamoeba histolytica exacerbates epithelial tight junction permeability and proinflammatory responses in Muc2(-/-) mice. THE AMERICAN JOURNAL OF PATHOLOGY 2013; 182:852-65. [PMID: 23357502 DOI: 10.1016/j.ajpath.2012.11.035] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 10/29/2012] [Accepted: 11/19/2012] [Indexed: 12/18/2022]
Abstract
Human mucin-2 (MUC-2) is the first line of innate host defense in preventing pathogen-induced epithelial injury. Entamoeba histolytica (Eh) colonizes the mucus layer by binding of the parasite's surface galactose lectin to galactose and N-acetyl-d-galactosamine residues on colonic MUC-2, preventing parasite contact-dependent cytolysis of epithelial cells. We quantified early innate responses to Eh in wild-type and MUC-2-deficient mice (Muc2(-/-)) using closed colonic loops. Eh infection in wild-type but not Muc2(-/-) mice induced a time-dependent increase in (3)H-labeled mucin and nonmucin glycoprotein secretions. Immunohistochemical staining revealed intense MUC-2 secretion, which formed a thick, protective mucus plug overlying the surface epithelium, entrapping Eh. In Muc2(-/-) mice, Eh induced a pronounced time-dependent secretory exudate with increased gross pathology scores and serum albumin leakage. Colonic pathology, secretory responses, and increased proinflammatory cytokine secretions of TNF-α, IFN-γ, and IL-13 correlated with altered expression of the tight junction proteins claudin-2, occludin, and ZO-1. We identified the putative Eh virulence factor that elicits the proinflammatory responses and alters tight junction permeability as Eh cysteine protease A5 (EhCP-A5). The present findings demonstrate that colonic mucins confer both luminal and epithelial barrier functions and that, in the absence of MUC-2, mice are more susceptible to Eh-induced secretory and proinflammatory responses mediated by EhCP-A5.
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Hayashi N, Matsukawa M, Horinishi Y, Nakai K, Shoji A, Yoneko Y, Yoshida N, Minagawa S, Gotoh N. Interplay of flagellar motility and mucin degradation stimulates the uassociation of Pseudomonas aeruginosa with human epithelial colorectal adenocarcinoma (Caco-2) cells. J Infect Chemother 2013; 19:305-15. [DOI: 10.1007/s10156-013-0554-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 01/07/2013] [Indexed: 01/02/2023]
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178
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Di Bartolomeo F, Startek JB, Van den Ende W. Prebiotics to fight diseases: reality or fiction? Phytother Res 2012; 27:1457-73. [PMID: 23280537 DOI: 10.1002/ptr.4901] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2012] [Revised: 11/10/2012] [Accepted: 11/12/2012] [Indexed: 12/18/2022]
Abstract
Bacteria living in the gastrointestinal tract are crucial for human health and disease occurrence. Increasing the beneficial intestinal microflora by consumption of prebiotics, which are 'functional foods', could be an elegant way to limit the number and incidence of disorders and to recover from dysbiosis or antibiotic treatments. This review focuses on the short-chain low-digestible carbohydrates (LDCs) which are metabolized by gut microbiota serving as energy source, immune system enhancers or facilitators of mineral uptake. Intake of foods containing LDCs can improve the state of health and may prevent diseases as for example certain forms of cancer. Given the large number of different molecules belonging to LDCs, we focused our attention on fructans (inulin, fructo-oligosaccharides), galacto-oligosaccharides and resistant starches and their therapeutic and protective applications. Evidence is accumulating that LDCs can inhibit bacterial and viral infections by modulating host defense responses and by changing the interactions between pathogenic and beneficial bacteria. Animal studies and studies on small groups of human subjects suggest that LDCs might help to counteract colorectal cancer, diabetes and metabolic syndrome. The action mechanisms of LDCs in the human body might be broader than originally thought, perhaps also including reactive oxygen species scavenging and signaling events.
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Affiliation(s)
- F Di Bartolomeo
- Laboratory of Molecular Plant Biology and Leuven Food Science and Nutrition Research Centre (LFoRCe), Kasteelpark Arenberg 31, 3001, Leuven, Belgium; University of the Studies of Molise - Department of Agriculture Food and Environment (D.A.A.A.) - Terzo edificio polifunzionale, Via de Sanctis, 86100, Campobasso, Italy
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Rakhshandeh A, Dekkers JCM, Kerr BJ, Weber TE, English J, Gabler NK. Effect of immune system stimulation and divergent selection for residual feed intake on digestive capacity of the small intestine in growing pigs1. J Anim Sci 2012; 90 Suppl 4:233-5. [DOI: 10.2527/jas.53976] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- A. Rakhshandeh
- Department of Animal Science, Iowa State University, Ames, IA50011
| | - J. C. M. Dekkers
- Department of Animal Science, Iowa State University, Ames, IA50011
| | | | | | - J. English
- Department of Animal Science, Iowa State University, Ames, IA50011
| | - N. K. Gabler
- Department of Animal Science, Iowa State University, Ames, IA50011
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180
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Abstract
The intestinal barrier serves 2 critical functions for the survival of the individual: first, it allows nutrient absorption and second, it defends the body from dangerous macromolecule penetration. It is a complex multilayer system, consisting of an external "anatomic" barrier and an inner "functional" immunological barrier. The interaction of these 2 barriers enables equilibrated permeability to be maintained. Many factors can alter this balance: gut microflora modifications, mucus layer alterations, and epithelial damage can increase intestinal permeability, allowing the translocation of luminal content to the inner layer of intestinal wall. Several techniques are now available that enable us to study gut permeability: "in vitro" models (Caco-2 and HT29-MTX cells) and "in vivo" not invasive tests (sugar tests and radioisotope scanning tests) are used to estimate permeability and to suggest molecular pathophysiological mechanisms of intestinal permeability in health and diseases. Many medicinal products used in the treatment of gastrointestinal diseases have also found to play an active role in modulate intestinal permeability: corticosteroids, 5-aminosalicylic acid, anti-tumor necrosis factor, probiotics, and mucosal protectors, like gelatin tannate. This review will particularly address the role of the gut barrier in maintaining intestinal permeability (microbiota, mucus, and epithelial cells), the techniques used for estimating intestinal permeability and the therapeutic approaches able to modify it.
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Estensoro I, Redondo MJ, Salesa B, Kaushik S, Pérez-Sánchez J, Sitjà-Bobadilla A. Effect of nutrition and Enteromyxum leei infection on gilthead sea bream Sparus aurata intestinal carbohydrate distribution. DISEASES OF AQUATIC ORGANISMS 2012; 100:29-42. [PMID: 22885511 DOI: 10.3354/dao02486] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The effect of a practical plant protein-based diet containing vegetable oils (VO) as the major lipid source on the mucosal carbohydrate pattern of the intestine was studied in gilthead sea bream Sparus aurata challenged with the myxosporean parasite Enteromyxum leei. Fish fed for 9 mo either a fish oil (FO) diet or a blend of VO at 66% of replacement (66VO diet) were exposed to parasite-contaminated water effluent. Samples of the anterior, middle and posterior intestine (AI, MI and PI, respectively) were obtained for parasite diagnosis and histochemistry. Fish were categorised as control (C, not exposed), early (E) or late (L) infected. Mucin and lectin histochemistry was applied to detect the different types of mucins and sialic acid in goblet cells (GC), the brush border and enterocytes. The number of GC stained with periodic acid Schiff (PAS), alcian blue (AB), aldehyde fuchsin-alcian blue (AF-AB), for the detection of neutral, acidic, sulphated and carboxylic mucins, and with the lectin Sambucus nigra agglutinin (SNA), were counted in digital images. The 66VO diet produced a significant decrease of GC with neutral and acidic mucins in the AI and MI, and also of those with carboxylic mucins and sialic acid in the MI. Sulphated mucins and sialic acid were less abundant in the AI than in the MI and PI in the C-66VO treatment. E. leei infection had a strong effect on the number of GC, as E and L infected fish had a significant decrease of GC positive for all the stains versus C fish in PI. Time and diet effects were also observed, since the lowest values were mostly registered in E-66VO fish in PI. In conclusion, though GC depletion was mainly induced by enteromyxosis, an effect of the diet was also observed. Thus, the diet can be a predisposing factor that worsens the disease course.
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Affiliation(s)
- Itziar Estensoro
- Instituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas, Torre la Sal s/n, 12595 Ribera de Cabanes, Castellón, Spain
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182
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Influence of adhesion and bacteriocin production by Lactobacillus salivarius on the intestinal epithelial cell transcriptional response. Appl Environ Microbiol 2012; 78:5196-203. [PMID: 22610429 DOI: 10.1128/aem.00507-12] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Lactobacillus salivarius strain UCC118 is a human intestinal isolate that has been extensively studied for its potential probiotic effects in human and animal models. The objective of this study was to determine the effect of L. salivarius UCC118 on gene expression responses in the Caco-2 cell line to improve understanding of how the strain might modulate intestinal epithelial cell phenotypes. Exposure of Caco-2 cells to UCC118 led to the induction of several human genes (TNFAIP3, NFKBIA, and BIRC3) that are negative regulators of inflammatory signaling pathways. Induction of chemokines (CCL20, CXCL-1, and CXCL-2) with antimicrobial functions was also observed. Disruption of the UCC118 sortase gene srtA causes reduced bacterial adhesion to epithelial cells. Transcription of three mucin genes was reduced significantly when Caco-2 cells were stimulated with the ΔsrtA derivative of UCC118 compared to cells stimulated with the wild type, but there was no significant change in the transcription levels of the anti-inflammatory genes. UCC118 genes that were significantly upregulated upon exposure to Caco-2 cells were identified by bacterial genome microarray and consisted primarily of two groups of genes connected with purine metabolism and the operon for synthesis of the Abp118 bacteriocin. Following incubation with Caco-2 cells, the bacteriocin synthesis genes were transcribed at higher levels in the wild type than in the ΔsrtA derivative. These data indicate that L. salivarius UCC118 influences epithelial cells both through modulation of the inflammatory response and by modulation of intestinal cell mucin production. Sortase-anchored cell surface proteins of L. salivarius UCC118 have a central role in promoting the interaction between the bacterium and epithelial cells.
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183
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Howell JC, Wells JM. Generating intestinal tissue from stem cells: potential for research and therapy. Regen Med 2012; 6:743-55. [PMID: 22050526 DOI: 10.2217/rme.11.90] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Intestinal resection and malformations in adult and pediatric patients result in devastating consequences. Unfortunately, allogeneic transplantation of intestinal tissue into patients has not been met with the same measure of success as the transplantation of other organs. Attempts to engineer intestinal tissue in vitro include disaggregation of adult rat intestine into subunits called organoids, harvesting native adult stem cells from mouse intestine and spontaneous generation of intestinal tissue from embryoid bodies. Recently, by utilizing principles gained from the study of developmental biology, human pluripotent stem cells have been demonstrated to be capable of directed differentiation into intestinal tissue in vitro. Pluripotent stem cells offer a unique and promising means to generate intestinal tissue for the purposes of modeling intestinal disease, understanding embryonic development and providing a source of material for therapeutic transplantation.
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Affiliation(s)
- Jonathan C Howell
- Division of Endocrinology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA
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184
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Pieper R, Kröger S, Richter JF, Wang J, Martin L, Bindelle J, Htoo JK, von Smolinski D, Vahjen W, Zentek J, Van Kessel AG. Fermentable fiber ameliorates fermentable protein-induced changes in microbial ecology, but not the mucosal response, in the colon of piglets. J Nutr 2012; 142:661-7. [PMID: 22357743 DOI: 10.3945/jn.111.156190] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Dietary inclusion of fermentable carbohydrates (fCHO) is reported to reduce large intestinal formation of putatively toxic metabolites derived from fermentable proteins (fCP). However, the influence of diets high in fCP concentration on epithelial response and interaction with fCHO is still unclear. Thirty-two weaned piglets were fed 4 diets in a 2 × 2 factorial design with low fCP/low fCHO [14.5% crude protein (CP)/14.5% total dietary fiber (TDF)]; low fCP/high fCHO (14.8% CP/16.6% TDF); high fCP low fCHO (19.8% CP/14.5% TDF); and high fCP/high fCHO (20.1% CP/18.0% TDF) as dietary treatments. After 21-23 d, pigs were killed and colon digesta and tissue samples analyzed for indices of microbial ecology, tissue expression of genes for cell turnover, cytokines, mucus genes (MUC), and oxidative stress indices. Pig performance was unaffected by diet. fCP increased (P < 0.05) cell counts of clostridia in the Clostridium leptum group and total short and branched chain fatty acids, ammonia, putrescine, histamine, and spermidine concentrations, whereas high fCHO increased (P < 0.05) cell counts of clostridia in the C. leptum and C. coccoides groups, shifted the acetate to propionate ratio toward acetate (P < 0.05), and reduced ammonia and putrescine (P < 0.05). High dietary fCP increased (P < 0.05) expression of PCNA, IL1β, IL10, TGFβ, MUC1, MUC2, and MUC20, irrespective of fCHO concentration. The ratio of glutathione:glutathione disulfide was reduced (P < 0.05) by fCP and the expression of glutathione transferase was reduced by fCHO (P < 0.05). In conclusion, fermentable fiber ameliorates fermentable protein-induced changes in most measures of luminal microbial ecology but not the mucosal response in the large intestine of pigs.
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Affiliation(s)
- Robert Pieper
- Institute of Animal Nutrition, Freie Universität Berlin, Berlin, Germany
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185
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Barnett AM, Roy NC, McNabb WC, Cookson AL. The interactions between endogenous bacteria, dietary components and the mucus layer of the large bowel. Food Funct 2012; 3:690-9. [DOI: 10.1039/c2fo30017f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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186
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Ashida H, Ogawa M, Kim M, Mimuro H, Sasakawa C. Bacteria and host interactions in the gut epithelial barrier. Nat Chem Biol 2011; 8:36-45. [PMID: 22173358 DOI: 10.1038/nchembio.741] [Citation(s) in RCA: 219] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The gut mucosa acts as a barrier against microbial invaders, whereas resident commensal and foreign invading bacteria interact intimately with the gut epithelium and influence the host cellular and immune systems. The epithelial barrier serves as an infectious foothold for many bacterial pathogens and as an entry port for pathogens to disseminate into deeper tissues. Enteric bacterial pathogens can efficiently infect the gut mucosa using highly sophisticated virulence mechanisms that allow bacteria to circumvent the defense barriers in the gut. We provide an overview of the components of the mucosal barrier and discuss the bacterial stratagems that circumvent these barriers with particular emphasis on the roles of bacterial effector proteins.
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Affiliation(s)
- Hiroshi Ashida
- Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo, Japan
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187
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Croix JA, Bhatia S, Gaskins HR. Inflammatory cues modulate the expression of secretory product genes, Golgi sulfotransferases and sulfomucin production in LS174T cells. Exp Biol Med (Maywood) 2011; 236:1402-12. [PMID: 22101519 DOI: 10.1258/ebm.2011.011186] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The signals that mediate goblet cell expression of specific mucin chemotypes are poorly defined. Animal and in vitro studies show that acidomucin chemotypes may be altered by inflammation and changes in intestinal microbiota. To examine factors that may elicit this response, human adenocarcinoma-derived LS174T cells, which have a goblet cell-like phenotype and produce both sulfo- and sialomucins, were used to examine the effects of selected microbial and host factors on expression of goblet cell secretory product genes, sulfotransferases and sulfomucin production. Expression of genes encoding mucin 2 (MUC2), resistin-like molecule β (RETNLB), and trefoil factor 3 (TFF3) and Golgi sulfotransferases, carbohydrate (N-acetylglucosamine 6-O) sulfotransferase 5 (CHST5) and galactose-3-O-sulfotransferase 2 (GAL3ST2), was measured by quantitative reverse transcriptase-polymerase chain reaction following treatment with bacterial flagellin, tumor necrosis factor α (TNF-α) or the mucogenic cytokine interleukin-13 (IL-13). Expression of the toll-like receptor 5 (TLR5) gene was also analysed. Sulfomucin expression was examined via high-iron diamide/alcian blue (HID/AB) histochemistry and immunofluorescent staining for the Sulfo Le(a) antigen, which is synthesized in part by GAL3ST2. Flagellin, IL-13 and TNF-α all significantly increased GAL3ST2, MUC2, TFF3 and TLR5 expression, while only IL-13 increased RETNLB and CHST5 expression. Based on HID/AB histochemistry, mucin sulfation was significantly increased in response to both flagellin and IL-13 but not TNF-α. Only treatment with flagellin increased the expression of the Sulfo Le(a) antigen. Collectively, these results indicate that bacterial flagellin, IL-13 and TNF-α differentially modulate the expression of goblet cell secretory product genes, sulfotransferases and sulfomucin production.
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Affiliation(s)
- Jennifer A Croix
- Division of Nutritional Sciences, University of Illinois, 1207 W. Gregory Dr. Urbana, Urbana, IL 61801, USA
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188
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Langerholc T, Maragkoudakis PA, Wollgast J, Gradisnik L, Cencic A. Novel and established intestinal cell line models - An indispensable tool in food science and nutrition. Trends Food Sci Technol 2011; 22:S11-S20. [PMID: 32336880 PMCID: PMC7172287 DOI: 10.1016/j.tifs.2011.03.010] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This review presents the applications of intestinal cell models of human and pig origin in food and nutritional sciences and highlights their potential as in vitro platforms for preclinical research. Intestinal cell models are used in studies of bioavailability, adsorption and transport in nutritional or toxicological settings, allergic effects of food components, as well as probiotics and/or host-pathogen gut interactions. In addition, this review discusses the advantages of using specialized and functional cell models over generic cancer-derived cell lines.
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Affiliation(s)
- Tomaz Langerholc
- Dep. of Microbiology, Biochemistry, Molecular Biology and Biotechnology, Faculty of Agriculture and Life Science, University of Maribor, Pivola 10, 2311 Hoce, Slovenia
| | - Petros A Maragkoudakis
- European Commission - Joint Research Centre - Institute for Health and Consumer Protection, Via Enrico Fermi 2749, 21027 Ispra (VA), Italy
| | - Jan Wollgast
- European Commission - Joint Research Centre - Institute for Health and Consumer Protection, Via Enrico Fermi 2749, 21027 Ispra (VA), Italy
| | - Lidija Gradisnik
- Dep. of Biochemistry and Nutrition, Faculty of Medicine, University of Maribor, Slomskov trg 15, 2000 Maribor, Slovenia
| | - Avrelija Cencic
- Dep. of Microbiology, Biochemistry, Molecular Biology and Biotechnology, Faculty of Agriculture and Life Science, University of Maribor, Pivola 10, 2311 Hoce, Slovenia
- Dep. of Biochemistry and Nutrition, Faculty of Medicine, University of Maribor, Slomskov trg 15, 2000 Maribor, Slovenia
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189
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Lu P, Burger-van Paassen N, van der Sluis M, Witte-Bouma J, Kerckaert JP, van Goudoever JB, Van Seuningen I, Renes IB. Colonic gene expression patterns of mucin Muc2 knockout mice reveal various phases in colitis development. Inflamm Bowel Dis 2011; 17:2047-57. [PMID: 21910166 DOI: 10.1002/ibd.21592] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Accepted: 11/02/2010] [Indexed: 12/26/2022]
Abstract
BACKGROUND Mucin Muc2 knockout (Muc2(-/-)) mice spontaneously develop colitis. METHODS To identify genes and biological responses which play a pivotal role during colitis development in Muc2(-/-) mice, gene expression profiles of colonic tissues from 2- and 4-week-old Muc2(-/-) and wildtype mice were determined using microarrays. RESULTS The majority of highly upregulated genes in 2-week-old as well as 4-week-old Muc2(-/-) mice were primarily involved in immune responses related to antigen processing/presentation, B-cell and T-cell receptor signaling, leukocyte transendothelial migration, and Jak-STAT signaling. Specifically, Muc2(-/-) mice expressed high levels of immunoglobulins, murine histocompatibility-2, proinflammatory cytokines, chemokines, and antimicrobial proteins. Additionally, in 4-week-old Muc2(-/-) mice, expression of genes involved in cell structure related pathways was significantly altered. Particularly, the tight junction-associated gene claudin-10 was upregulated, whereas claudin-1 and claudin-5 were downregulated. Furthermore, 4-week-old Muc2(-/-) mice showed increased expression of genes regulating cell growth in conjunction with increased crypt length and increased epithelial proliferation. CONCLUSIONS Muc2-deficiency leads to an active inflammatory response in 2- and 4-week-old Muc2(-/-) mice as demonstrated by the altered expression in immune response related genes. In addition, 4-week-old Muc2(-/-) mice also showed a decrease in epithelial barrier function and an increase in epithelial proliferation as indicated by, respectively, the altered expression in tight junction-related genes and upregulation of genes stimulating cell growth. Remarkably, upregulation of genes stimulating cell growth correlated with increased crypt length and increased epithelial proliferation in 4-week-old Muc2(-/-) mice. Together, these data demonstrate that there are distinct phases in colitis development in 2-4-week-old Muc2(-/-) mice.
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Affiliation(s)
- Peng Lu
- Laboratory of Pediatrics, Division Neonatology, Erasmus MC-Sophia, Rotterdam, The Netherlands
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190
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Dharmani P, Leung P, Chadee K. Tumor necrosis factor-α and Muc2 mucin play major roles in disease onset and progression in dextran sodium sulphate-induced colitis. PLoS One 2011; 6:e25058. [PMID: 21949848 PMCID: PMC3176316 DOI: 10.1371/journal.pone.0025058] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Accepted: 08/26/2011] [Indexed: 12/17/2022] Open
Abstract
The sequential events and the inflammatory mediators that characterize disease onset and progression of ulcerative colitis (UC) are not well known. In this study, we evaluated the early pathologic events in the pathogenesis of colonic ulcers in rats treated with dextran sodium sulfate (DSS). Following a lag phase, day 5 of DSS treatment was found clinically most critical as disease activity index (DAI) exhibited an exponential rise with severe weight loss and rectal bleeding. Surprisingly, on days 1-2, colonic TNF-α expression (70-80-fold) and tissue protein (50-fold) were increased, whereas IL-1β only increased on days 7-9 (60-90-fold). Days 3-6 of DSS treatment were characterized by a prominent down regulation in the expression of regulatory cytokines (40-fold for IL-10 and TGFβ) and mucin genes (15-18 fold for Muc2 and Muc3) concomitant with depletion of goblet cell and adherent mucin. Remarkably, treatment with TNF-α neutralizing antibody markedly altered DSS injury with reduced DAI, restoration of the adherent and goblet cell mucin and IL-1β and mucin gene expression. We conclude that early onset colitis is dependent on TNF-α that preceded depletion of adherent and goblet cell mucin prior to epithelial cell damage and these biomarkers can be used as therapeutic targets for UC.
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Affiliation(s)
- Poonam Dharmani
- Department of Microbiology, Immunology and Infectious Diseases, Gastrointestinal Research Group, Health Sciences Centre, University of Calgary, Calgary, Alberta, Canada
| | - Pearl Leung
- Department of Microbiology, Immunology and Infectious Diseases, Gastrointestinal Research Group, Health Sciences Centre, University of Calgary, Calgary, Alberta, Canada
| | - Kris Chadee
- Department of Microbiology, Immunology and Infectious Diseases, Gastrointestinal Research Group, Health Sciences Centre, University of Calgary, Calgary, Alberta, Canada
- * E-mail:
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191
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Jacobsen M, Cirera S, Joller D, Esteso G, Kracht SS, Edfors I, Bendixen C, Archibald AL, Vogeli P, Neuenschwander S, Bertschinger HU, Rampoldi A, Andersson L, Fredholm M, Jørgensen CB. Characterisation of five candidate genes within the ETEC F4ab/ac candidate region in pigs. BMC Res Notes 2011; 4:225. [PMID: 21718470 PMCID: PMC3160978 DOI: 10.1186/1756-0500-4-225] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 06/30/2011] [Indexed: 12/22/2022] Open
Abstract
Background Enterotoxigenic Escherichia coli (ETEC) that express the F4ab and F4ac fimbriae is a major contributor to diarrhoea outbreaks in the pig breeding industry, infecting both newborn and weaned piglets. Some pigs are resistant to this infection, and susceptibility is inherited as a simple dominant Mendelian trait. Indentifying the genetics behind this trait will greatly benefit pig welfare as well as the pig breeding industry by providing an opportunity to select against genetically susceptible animals, thereby reducing the number of diarrhoea outbreaks. The trait has recently been mapped by haplotype sharing to a 2.5 Mb region on pig chromosome 13, a region containing 18 annotated genes. Findings The coding regions of five candidate genes for susceptibility to ETEC F4ab/ac infection (TFRC, ACK1, MUC20, MUC4 and KIAA0226), all located in the 2.5 Mb region, were investigated for the presence of possible causative mutations. A total of 34 polymorphisms were identified in either coding regions or their flanking introns. The genotyping data for two of those were found to perfectly match the genotypes at the ETEC F4ab/ac locus, a G to C polymorphism in intron 11 of TFRC and a C to T silent polymorphism in exon 22 of KIAA0226. Transcriptional profiles of the five genes were investigated in a porcine tissue panel including various intestinal tissues. All five genes were expressed in intestinal tissues at different levels but none of the genes were found differentially expressed between ETEC F4ab/ac resistant and ETEC F4ab/ac susceptible animals in any of the tested tissues. Conclusions None of the identified polymorphisms are obvious causative mutations for ETEC F4ab/ac susceptibility, as they have no impact on the level of the overall mRNA expression nor predicted to influence the composition of the amino acids composition. However, we cannot exclude that the five tested genes are bona fide candidate genes for susceptibility to ETEC F4ab/ac infection since the identified polymorphism might affect the translational apparatus, alternative splice forms may exist and post translational mechanisms might contribute to disease susceptibility.
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Affiliation(s)
- Mette Jacobsen
- Department of Basic Animal and Veterinary Sciences, University of Copenhagen, 1870 Frederiksberg, Denmark.
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192
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Coagulation, an ancestral serine protease cascade, exerts a novel function in early immune defense. Blood 2011; 118:2589-98. [PMID: 21613262 DOI: 10.1182/blood-2011-02-337568] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Phylogenetically conserved serine protease cascades play an important role in invertebrate and vertebrate immunity. The mammalian coagulation system can be traced back some 400 million years and shares homology with ancestral serine proteinase cascades that are involved in, for example, Toll receptor signaling in insects and release of antimicrobial peptides during hemolymph clotting. In the present study, we show that the induction of coagulation by bacteria leads to immobilization and killing of Streptococcus pyogenes bacteria inside the clot. The entrapment is mediated via cross-linking of bacteria to fibrin fibers by the action of coagulation factor XIII (fXIII), an evolutionarily conserved transglutaminase. In a streptococcal skin infection model, fXIII(-/-) mice developed severe signs of pathologic inflammation at the local site of infection, and fXIII treatment of wild-type animals dampened bacterial dissemination during early infection. Bacterial killing and cross-linking to fibrin networks was also detected in tissue biopsies from patients with streptococcal necrotizing fasciitis, supporting the concept that coagulation is part of the early innate immune system.
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193
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Muc-2-deficient mice display a sex-specific, COX-2-related impairment of gastric mucosal repair. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 178:1126-33. [PMID: 21356364 DOI: 10.1016/j.ajpath.2010.11.048] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 10/18/2010] [Accepted: 11/15/2010] [Indexed: 12/18/2022]
Abstract
Mucus is known to contribute significantly to the prevention and repair of mucosal damage throughout the gastrointestinal tract. Although not normally expressed in the stomach, mucin-2 (MUC-2, encoded by the MUC2 gene) is expressed in certain disease states. The aim of this study was to determine in a mouse model whether the absence of Muc-2 would result in impaired susceptibility to and healing of gastric mucosal injury. Acute gastric damage was induced in mice deficient in Muc-2 and in wild-type controls, through oral administration of indomethacin. Chronic gastric ulcers were induced by serosal application of acetic acid. The extent of injury and the extent of healing of the damage over time were examined in both models. Indomethacin administration caused similar levels of gastric damage in Muc-2-deficient and wild-type mice, but the erosions healed more slowly in the former. Acetic acid-induced gastric ulcers were initially similar in size in Muc-2-deficient and wild-type mice of both sexes, but ulcer healing was significantly impaired in male Muc-2-deficient mice. Induction of cyclooxygenase-2 in the stomach, in response to indomethacin- or acetic acid-induced ulceration, was significantly reduced in male Muc-2-deficient mice. This phenomenon, and the sex specificity, was also apparent in bone marrow-derived macrophages stimulated with endotoxin. These results demonstrate a marked impairment of gastric mucosal repair in male Muc-2-deficient mice that may be related to an insufficient induction of cyclooxygenase-2, an enzyme known to contribute to mucosal repair.
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194
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Lactobacillus adhesion to mucus. Nutrients 2011; 3:613-36. [PMID: 22254114 PMCID: PMC3257693 DOI: 10.3390/nu3050613] [Citation(s) in RCA: 192] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Revised: 05/05/2011] [Accepted: 05/11/2011] [Indexed: 12/12/2022] Open
Abstract
Mucus provides protective functions in the gastrointestinal tract and plays an important role in the adhesion of microorganisms to host surfaces. Mucin glycoproteins polymerize, forming a framework to which certain microbial populations can adhere, including probiotic Lactobacillus species. Numerous mechanisms for adhesion to mucus have been discovered in lactobacilli, including partially characterized mucus binding proteins. These mechanisms vary in importance with the in vitro models studied, which could significantly affect the perceived probiotic potential of the organisms. Understanding the nature of mucus-microbe interactions could be the key to elucidating the mechanisms of probiotic adhesion within the host.
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195
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Modulation of intestinal morphology and immunity in nile tilapia (Oreochromis niloticus) by Lactobacillus rhamnosus GG. Res Vet Sci 2011; 91:e92-7. [PMID: 21536310 DOI: 10.1016/j.rvsc.2011.02.014] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2009] [Revised: 01/30/2011] [Accepted: 02/20/2011] [Indexed: 12/12/2022]
Abstract
The use of lactic acid bacteria from human origins as a potential probiotic supplementation in aquaculture feed is now widely accepted. Here, we examined some of the properties and mechanisms of the action of Lactobacillus rhamnosus GG, originating from humans, on growth performance, gut mucosal immunity and humoral and cellular immune response in tilapia (Oreochromis niloticus). The results suggested that supplementation of L. rhamnosus gave an advantage in promoting the intestinal structure and the mucosal immunity of tilapia. Probiotic fish had a greater villous height in all parts of the intestines and, significantly, in the proximal and middle part. The population of intraepithelial lymphocytes was significantly higher in the probiotic group than in the control group in all parts of the intestines. The population of acidophilic granulocyte in the probiotic group was significantly higher at the proximal and distal parts when compared with the control group. The higher serum complement activity as well as the enhanced phagocytosis and killing ability of the head kidney leukocytes in the probiotic supplemented fish corresponded with the higher level of TNF alpha and IL-1 gene expression, suggesting that the induction of IL-1 and TNF alpha cytokines by L. rhamnosus served as an important regulator of gut associated immune systems.
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196
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Abstract
This review discusses the barriers an enteric pathogen encounters when establishing an infection in the intestinal tract. There are potential barriers in the lumen that increase competition for nutrients and space. The role of mucus layer, and the antimicrobial peptides and secretory IgA sequestered within it, are also significant barriers. After overcoming these defences, the pathogen encounters the epithelial layer. This layer can be broken down into various protective components including enterocytes, Paneth cells, goblet cells, M cells and pathogen recognition receptors. Collectively, these intestinal defences constitute significant barriers that pathogens must overcome to successfully colonize this important mucosal surface.
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Affiliation(s)
- Navkiran Gill
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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197
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Antibiotic treatment alters the colonic mucus layer and predisposes the host to exacerbated Citrobacter rodentium-induced colitis. Infect Immun 2011; 79:1536-45. [PMID: 21321077 DOI: 10.1128/iai.01104-10] [Citation(s) in RCA: 287] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Antibiotics are often used in the clinic to treat bacterial infections, but the effects of these drugs on microbiota composition and on intestinal immunity are poorly understood. Citrobacter rodentium was used as a model enteric pathogen to investigate the effect of microbial perturbation on intestinal barriers and susceptibility to colitis. Streptomycin and metronidazole were used to induce alterations in the composition of the microbiota prior to infection with C. rodentium. Metronidazole pretreatment increased susceptibility to C. rodentium-induced colitis over that of untreated and streptomycin-pretreated mice, 6 days postinfection. Both antibiotic treatments altered microbial composition, without affecting total numbers, but metronidazole treatment resulted in a more dramatic change, including a reduced population of Porphyromonadaceae and increased numbers of lactobacilli. Disruption of the microbiota with metronidazole, but not streptomycin treatment, resulted in an increased inflammatory tone of the intestine characterized by increased bacterial stimulation of the epithelium, altered goblet cell function, and thinning of the inner mucus layer, suggesting a weakened mucosal barrier. This reduction in mucus thickness correlates with increased attachment of C. rodentium to the intestinal epithelium, contributing to the exacerbated severity of C. rodentium-induced colitis in metronidazole-pretreated mice. These results suggest that antibiotic perturbation of the microbiota can disrupt intestinal homeostasis and the integrity of intestinal defenses, which protect against invading pathogens and intestinal inflammation.
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Cinova J, De Palma G, Stepankova R, Kofronova O, Kverka M, Sanz Y, Tuckova L. Role of intestinal bacteria in gliadin-induced changes in intestinal mucosa: study in germ-free rats. PLoS One 2011; 6:e16169. [PMID: 21249146 PMCID: PMC3020961 DOI: 10.1371/journal.pone.0016169] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Accepted: 12/13/2010] [Indexed: 02/07/2023] Open
Abstract
Background and Aims Celiac disease (CD) is a chronic inflammatory disorder of the small intestine that is induced by dietary wheat gluten proteins (gliadins) in genetically predisposed individuals. The overgrowth of potentially pathogenic bacteria and infections has been suggested to contribute to CD pathogenesis. We aimed to study the effects of gliadin and various intestinal bacterial strains on mucosal barrier integrity, gliadin translocation, and cytokine production. Methodology/Principal Findings Changes in gut mucosa were assessed in the intestinal loops of inbred Wistar-AVN rats that were reared under germ-free conditions in the presence of various intestinal bacteria (enterobacteria and bifidobacteria isolated from CD patients and healthy children, respectively) and CD-triggering agents (gliadin and IFN-γ) by histology, scanning electron microscopy, immunofluorescence, and a rat cytokine antibody array. Adhesion of the bacterial strains to the IEC-6 rat cell line was evaluated in vitro. Gliadin fragments alone or together with the proinflammatory cytokine interferon (IFN)-γ significantly decreased the number of goblet cells in the small intestine; this effect was more pronounced in the presence of Escherichia coli CBL2 and Shigella CBD8. Shigella CBD8 and IFN-γ induced the highest mucin secretion and greatest impairment in tight junctions and, consequently, translocation of gliadin fragments into the lamina propria. Shigella CBD8 and E. coli CBL2 strongly adhered to IEC-6 epithelial cells. The number of goblet cells in small intestine increased by the simultaneous incubation of Bifidobacterium bifidum IATA-ES2 with gliadin, IFN-γ and enterobacteria. B. bifidum IATA-ES2 also enhanced the production of chemotactic factors and inhibitors of metalloproteinases, which can contribute to gut mucosal protection. Conclusions Our results suggest that the composition of the intestinal microbiota affects the permeability of the intestinal mucosa and, consequently, could be involved in the early stages of CD pathogenesis.
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Affiliation(s)
- Jana Cinova
- Department of Immunology, Institute of Microbiology v.v.i., Academy of Sciences of the Czech Republic, Prague, Czech Republic.
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Kim YS, Ho SB. Intestinal goblet cells and mucins in health and disease: recent insights and progress. Curr Gastroenterol Rep 2011; 12:319-30. [PMID: 20703838 PMCID: PMC2933006 DOI: 10.1007/s11894-010-0131-2] [Citation(s) in RCA: 912] [Impact Index Per Article: 70.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The mucus layer coating the gastrointestinal tract is the front line of innate host defense, largely because of the secretory products of intestinal goblet cells. Goblet cells synthesize secretory mucin glycoproteins (MUC2) and bioactive molecules such as epithelial membrane-bound mucins (MUC1, MUC3, MUC17), trefoil factor peptides (TFF), resistin-like molecule beta (RELMbeta), and Fc-gamma binding protein (Fcgbp). The MUC2 mucin protein forms trimers by disulfide bonding in cysteine-rich amino terminal von Willebrand factor (vWF) domains, coupled with crosslinking provided by TFF and Fcgbp proteins with MUC2 vWF domains, resulting in a highly viscous extracellular layer. Colonization by commensal intestinal microbiota is limited to an outer "loose" mucus layer, and interacts with the diverse oligosaccharides of mucin glycoproteins, whereas an "inner" adherent mucus layer is largely devoid of bacteria. Defective mucus layers resulting from lack of MUC2 mucin, mutated Muc2 mucin vWF domains, or from deletion of core mucin glycosyltransferase enzymes in mice result in increased bacterial adhesion to the surface epithelium, increased intestinal permeability, and enhanced susceptibility to colitis caused by dextran sodium sulfate. Changes in mucin gene expression and mucin glycan structures occur in cancers of the intestine, contributing to diverse biologic properties involved in the development and progression of cancer. Further research is needed on identification and functional significance of various components of mucus layers and the complex interactions among mucus layers, microbiota, epithelial cells, and the underlying innate and adaptive immunity. Further elucidation of the regulatory mechanisms involved in mucin changes in cancer and inflammation may lead to the development of novel therapeutic approaches.
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Affiliation(s)
- Young S Kim
- Genemed Biotechnologies, 458 Carlton Court, South San Francisco, CA 94080, USA.
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Kissoon-Singh V, Mortimer L, Chadee K. Entamoeba histolytica Cathepsin-Like Enzymes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 712:62-83. [DOI: 10.1007/978-1-4419-8414-2_5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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