Die Internalisierung von Tight-Junction Proteinen nach IFN-γ Inkubation erfolgt Endozytose abhängig durch Makropinozytose

Background:Semaphorin 4D (SEMA4D) / CD100, known as a subfamily of axonal guidance proteins, has also been reported to act as an immunoregulator in several infectious and inflammatory diseases [1]. Sjögren’s syndrome (SS) is a systemic autoimmune disease that primarily affects the exocrine glands by infiltrated lymphocytes resulting in dryness of mouth and eyes. IL-17 was reported to impair the integrity of tight junction barrier and attenuate the expression of aquaporin 5 (AQP5), causing salivary gland dysfunction in SS [2].Objectives:This study was aimed to evaluate the role of SEMA4D in patients with SS and investigate the effect of SEMA4D on human salivary gland epithelial cell (SGEC) and T cell.Methods:Soluble SEMA4D levels in plasma were measured by enzyme-linked immunosorbent assay (ELISA) from patients with SS, non-SS sicca and healthy controls. Immortalized human SGECs, originated from acini (NS-SV-AC) and duct (NS-SV-DC), were used to evaluate the effects of SEMA4D. CD4+T cells from human peripheral blood were isolated to determine the secretion of cytokines in response to SEMA4D. IFN-γ and IL-17 were used to determine the effects on AQP5 expression of SGEC.Results:The levels of soluble SEMA4D in plasma were increased in patients with SS (median [interquartile range]: 1221.3 [393.5] pg/mL) compared to non-SS sicca (940.2 [355.1] pg/mL,p= 0.006) or healthy controls (909.5 [108.0] pg/mL,p <0.0001). The levels of soluble SEMA4D in plasma were correlated with the levels of several autoantibodies including anti-SSA (Spearman’s rho = 0.358,p= 0.006), anti-SSB (rho = 0.350,p= 0.007), and anti-muscarinic receptor 3 (M3R) Ab (rho = 0.495,p< 0.001), and also correlated with total IgG (rho = 0.431,p= 0.002). SEMA4D-stimulated SGECs showed decreased expression of tight junctions such as occludin and Zo-1. CD4+T cells secreted IFN-γ (p= 0.025), IL-17 (p= 0.028), and IL-21 (p= 0.007) with SEMA4D stimulation. IFN-γ and IL-17 decreased AQP5 expression in SGECs.Conclusion:SEMA4D contributed to decreased expression of tight junction in SGECs. SEMA4D induced production of IFN-γ and IL-17 in CD4+T cells and these cytokine decreased AQP5 expression in SGECs.References:[1]Worzfeld T, Offermanns S. Nat Rev Drug Discov. 2014;13(8):603-21.[2]Bhattarai KR, Junjappa R, Handigund M, Kim HR, Chae HJ. Autoimmun Rev. 2018;17(4):376-90.Disclosure of Interests:None declared

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TNF-α and IFN-γ affect on barrier function of tight junction in immortalized mouse cholangiocytes

Gastroenterology ◽

10.1016/s0016-5085(08)81768-4 ◽

2001 ◽

Vol 120 (5) ◽

pp. A356

Author(s):

Shinichiro Hanada ◽

Masaru Harada ◽

Shotaro Sakisaka ◽

Hironori Koga ◽

Takumi Kawaguchi ◽

...

Keyword(s):

Tight Junction ◽

Barrier Function ◽

Tnf Α ◽

Ifn Γ

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Effects of multi-strain probiotic supplementation on intestinal microbiota, tight junctions, and inflammation in young broiler chickens challenged with Salmonella enterica subsp. enterica

Asian-Australasian Journal of Animal Sciences ◽

10.5713/ajas.19.0427 ◽

2020 ◽

Vol 33 (11) ◽

pp. 1797-1808

Author(s):

Chi Huan Chang ◽

Po Yun Teng ◽

Tzu Tai Lee ◽

Bi Yu

Keyword(s):

Gene Expression ◽

Tight Junction ◽

Intestinal Microbiota ◽

Broiler Chickens ◽

Infected Group ◽

Tight Junction Proteins ◽

Probiotic Supplementation ◽

Mucin 2 ◽

Ifn Γ ◽

Junction Proteins

Objective: This study assessed the effects of probiotics on cecal microbiota, gene expression of intestinal tight junction proteins, and immune response in the cecal tonsil of broiler chickens challenged with Salmonella enterica subsp. enterica.Methods: One-day-old broiler chickens (n = 240) were randomly allocated to four treatments: negative control (Cont), multi-strain probiotic-treated group (Pro), Salmonella-infected group (Sal), and multi-strain probiotic-treated and Salmonella-infected group (ProSal). All chickens except those in the Cont and Pro groups were gavaged with 1×10<sup>8</sup> cfu/mL of S. enterica subsp. enterica 4 days after hatching.Results: Our results indicated that body weight, weight gain, and feed conversion ratio of birds were significantly reduced (p<0.05) by Salmonella challenge. Chickens challenged with Salmonella decreased cecal microbial diversity. Chickens in the Sal group exhibited abundant Proteobacteria than those in the Cont, Pro, and ProSal groups. Salmonella infection downregulated gene expression of Occludin, zonula occludens-1 (ZO1), and Mucin 2 in the jejunum and Occludin and Claudin in the ileum. Moreover, the Sal group increased gene expression of interferon-γ (IFN-γ), interleukin-6 (IL-6), IL-1β, and lipopolysaccharide-induced tumor necrosis factor-alpha factor (LITAF) and reduced levels of transforming growth factor-β4 and IL-10 compared with the other groups (p<0.05). However, chickens receiving probiotic diets increased Lactobacillaceae abundance and reduced Enterobacteriaceae abundance in the ceca. Moreover, supplementation with probiotics increased the mRNA expression of Occludin, ZO1, and Mucin 2 in the ileum (p<0.05). In addition, probiotic supplementation downregulated the mRNA levels of IFN-γ (p<0.05) and LITAF (p = 0.075) and upregulated IL-10 (p = 0.084) expression in the cecal tonsil.Conclusion: The administration of multi-strain probiotics modulated intestinal microbiota, gene expression of tight junction proteins, and immunomodulatory activity in broiler chickens.

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Secreted bioactive factors fromBifidobacterium infantisenhance epithelial cell barrier function

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.90227.2008 ◽

2008 ◽

Vol 295 (5) ◽

pp. G1025-G1034 ◽

Cited By ~ 303

Author(s):

Julia B. Ewaschuk ◽

Hugo Diaz ◽

Liisa Meddings ◽

Brendan Diederichs ◽

Andrea Dmytrash ◽

...

Keyword(s):

Epithelial Cell ◽

Tight Junction ◽

Cell Permeability ◽

Tight Junction Proteins ◽

Gut Permeability ◽

Tnf Α ◽

Ifn Γ ◽

The Impact ◽

Deficient Mice ◽

Junction Proteins

Live probiotic bacteria are effective in reducing gut permeability and inflammation. We have previously shown that probiotics release peptide bioactive factors that modulate epithelial resistance in vitro. The objectives of this study were to determine the impact of factors released from Bifidobacteria infantis on intestinal epithelial cell permeability and tight junction proteins and to assess whether these factors retain their bioactivity when administered to IL-10-deficient mice. B. infantis conditioned medium (BiCM) was applied to T84 human epithelial cells in the presence and absence of TNF-α and IFN-γ. Transepithelial resistance (TER), tight junction proteins [claudins 1, 2, 3, and 4, zonula occludens (ZO)-1, and occludin] and MAP kinase activity (p38 and ERK) were examined. Acute effects of BiCM on intestinal permeability were assessed in colons from IL-10-deficient mice in Ussing chambers. A separate group of IL-1-deficient mice was treated with BiCM for 4 wk and then assessed for intestinal histological injury, cytokine levels, epithelial permeability, and immune response to bacterial antigens. In T84 cells, BiCM increased TER, decreased claudin-2, and increased ZO-1 and occludin expression. This was associated with enhanced levels of phospho-ERK and decreased levels of phospho-p38. BiCM prevented TNF-α- and IFN-γ-induced drops in TER and rearrangement of tight junction proteins. Inhibition of ERK prevented the BiCM-induced increase in TER and attenuated the protection from TNF-α and IFN-γ. Oral BiCM administration acutely reduced colonic permeability in mice whereas long-term BiCM treatment in IL-10-deficient mice attenuated inflammation, normalized colonic permeability, and decreased colonic and splenic IFN-γ secretion. In conclusion, peptide bioactive factors from B. infantis retain their biological activity in vivo and are effective in normalizing gut permeability and improving disease in an animal model of colitis. The effects of BiCM are mediated in part by changes in MAP kinases and tight junction proteins.

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IFN-γ induziert Endozytose von Tight Junction Proteinen in vacuolare, apicale Kompartimente

Zeitschrift für Gastroenterologie ◽

10.1055/s-2005-919858 ◽

2005 ◽

Vol 43 (05) ◽

Author(s):

M Utech ◽

M Brüwer ◽

A Ivanov ◽

A Nusrat

Keyword(s):

Tight Junction ◽

Ifn Γ

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Mechanism of IFN-γ-induced Endocytosis of Tight Junction Proteins: Myosin II-dependent Vacuolarization of the Apical Plasma Membrane

Molecular Biology of the Cell ◽

10.1091/mbc.e05-03-0193 ◽

2005 ◽

Vol 16 (10) ◽

pp. 5040-5052 ◽

Cited By ~ 219

Author(s):

Markus Utech ◽

Andrei I. Ivanov ◽

Stanislav N. Samarin ◽

Matthias Bruewer ◽

Jerrold R. Turner ◽

...

Keyword(s):

Plasma Membrane ◽

Epithelial Cells ◽

Tight Junction ◽

Rho Gtpase ◽

Intestinal Inflammation ◽

Myosin Ii ◽

Apical Plasma Membrane ◽

T84 Cells ◽

Ifn Γ ◽

First Time

Disruption of epithelial barrier by proinflammatory cytokines such as IFN-γ represents a major pathophysiological consequence of intestinal inflammation. We have previously shown that IFN-γ increases paracellular permeability in model T84 epithelial cells by inducing endocytosis of tight junction (TJ) proteins occludin, JAM-A, and claudin-1. The present study was designed to dissect mechanisms of IFN-γ-induced endocytosis of epithelial TJ proteins. IFN-γ treatment of T84 cells resulted in internalization of TJ proteins into large actin-coated vacuoles that originated from the apical plasma membrane and resembled the vacuolar apical compartment (VAC) previously observed in epithelial cells that lose cell polarity. The IFN-γ dependent formation of VACs required ATPase activity of a myosin II motor but was not dependent on rapid turnover of F-actin. In addition, activated myosin II was observed to colocalize with VACs after IFN-γ exposure. Pharmacological analyses revealed that formation of VACs and endocytosis of TJ proteins was mediated by Rho-associated kinase (ROCK) but not myosin light chain kinase (MLCK). Furthermore, IFN-γ treatment resulted in activation of Rho GTPase and induced expressional up-regulation of ROCK. These results, for the first time, suggest that IFN-γ induces endocytosis of epithelial TJ proteins via RhoA/ROCK-mediated, myosin II-dependent formation of VACs.

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Gut DNA Virome Diversity and Its Association with Host Bacteria Regulate Inflammatory Phenotype and Neuronal Immunotoxicity in Experimental Gulf War Illness

Viruses ◽

10.3390/v11100968 ◽

2019 ◽

Vol 11 (10) ◽

pp. 968 ◽

Cited By ~ 14

Author(s):

Ratanesh K. Seth ◽

Rabia Maqsood ◽

Ayan Mondal ◽

Dipro Bose ◽

Diana Kimono ◽

...

Keyword(s):

Tight Junction ◽

Intestinal Inflammation ◽

Chronic Fatigue ◽

Gulf War ◽

Innate Immune ◽

Tight Junction Protein ◽

Gulf War Illness ◽

Antiviral Compound ◽

Junction Protein ◽

Ifn Γ

Gulf War illness (GWI) is characterized by the persistence of inflammatory bowel disease, chronic fatigue, neuroinflammation, headache, cognitive impairment, and other medically unexplained conditions. Results using a murine model show that enteric viral populations especially bacteriophages were altered in GWI. The increased viral richness and alpha diversity correlated positively with gut bacterial dysbiosis and proinflammatory cytokines. Altered virome signature in GWI mice also had a concomitant weakening of intestinal epithelial tight junctions with a significant increase in Claudin-2 protein expression and decrease in ZO1 and Occludin mRNA expression. The altered virome signature in GWI, decreased tight junction protein level was followed by the presence an activation of innate immune responses such as increased Toll-like receptor (TLR) signaling pathways. The altered virome diversity had a positive correlation with serum IL-6, IL-1β, and IFN-γ, intestinal inflammation (IFN-γ), and decreased Brain-Derived Neurotrophic Factor (BDNF), a neurogenesis marker. The co-exposure of Gulf War chemical and antibiotic (for gut sterility) or Gulf War chemical and Ribavirin, an antiviral compound to suppress virus alteration in the gut showed significant improvement in epithelial tight junction protein, decreased intestinal-, systemic-, and neuroinflammation. These results showed that the observed enteric viral dysbiosis could activate enteric viral particle-induced innate immune response in GWI and could be a novel therapeutic target in GWI.

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The JAK-Inhibitor Tofacitinib Rescues Human Intestinal Epithelial Cells and Colonoids from Cytokine-Induced Barrier Dysfunction

Inflammatory Bowel Diseases ◽

10.1093/ibd/izz266 ◽

2019 ◽

Vol 26 (3) ◽

pp. 407-422 ◽

Cited By ~ 5

Author(s):

Anica Sayoc-Becerra ◽

Moorthy Krishnan ◽

Shujun Fan ◽

Jossue Jimenez ◽

Rebecca Hernandez ◽

...

Keyword(s):

Epithelial Cells ◽

Tight Junction ◽

Tight Junctions ◽

Barrier Function ◽

Intestinal Epithelial Cells ◽

Janus Kinase ◽

Intestinal Epithelial ◽

Jak Inhibitor ◽

Barrier Dysfunction ◽

Ifn Γ

Abstract Background Alterations to epithelial tight junctions can compromise the ability of the epithelium to act as a barrier between luminal contents and the underlying tissues, thereby increasing intestinal permeability, an early critical event in inflammatory bowel disease (IBD). Tofacitinib (Xeljanz), an orally administered pan-Janus kinase (JAK) inhibitor, was recently approved for the treatment of moderate to severe ulcerative colitis. Nevertheless, the effects of tofacitinib on intestinal epithelial cell functions are largely unknown. The aim of this study was to determine if JAK inhibition by tofacitinib can rescue cytokine-induced barrier dysfunction in intestinal epithelial cells (IECs). Methods T84 IECs were used to evaluate the effects of tofacitinib on JAK-signal transducer and activator of transcription (STAT) activation, barrier permeability, and expression and localization of tight junction proteins. The impact of tofacitinib on claudin-2 promoter activity was assessed in HT-29 IECs. Tofacitinib rescue of barrier function was also tested in human colonic stem cell-derived organoids. Results Pretreatment with tofacitinib prevented IFN-γ-induced decreases in transepithelial electrical resistance (TER) and increases in 4 kDa FITC-dextran permeability (FD4), partly due to claudin-2 transcriptional regulation and restriction of ZO-1 rearrangement at tight junctions. Although tofacitinib administered after IFN-γ challenge only partially normalized TER and claudin-2 levels, FD4 permeability and ZO-1 localization were fully recovered. The IFN-γ-induced FD4 permeability in primary human colonoids was fully rescued by tofacitinib. Conclusions These data suggest differential therapeutic efficacy of tofacitinib in the rescue of pore vs leak-tight junction barrier defects and indicate a potential contribution of improved epithelial barrier function to the beneficial effects of tofacitinib in IBD patients.

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