Loss of epithelial barrier function is characteristic of inflammatory, infectious, ischemic, and immune mediated intestinal diseases. Synergistic signaling between the TH1 cytokines interferon-gamma (IFNgamma) and tumor necrosis factor-alpha (TNFalpha), which are frequently elevated in these diseases, has been implicated in this barrier dysfunction. In turn, compromised barrier function can allow noxious nominal material to access the lamina propria, stimulate immune cells, and augment IFNgamma and TNFalpha release, culminating in a self-amplifying cycle of epithelial dysfunction. In vivo data show that barrier dysfunction can be reversed by anti-TNF a therapies. We have recently shown that IFN gamma / TNFalpha -induced loss of barrier function is related to increased myosin light chain (MLC) phosphorylation and that both loss of barrier function and increased MLC phosphorylation can be reversed by a novel oligopeptide MLC kinase inhibitor. Despite this, the mechanisms by which IFNgamma / TNFalpha increase MLC phosphorylation and decrease barrier function are not well understood. Characterization of these regulatory mechanisms is important to understanding the pathogenesis of diverse intestinal diseases and may also identify novel targets for therapy of IFNgamma / TNFalpha -driven intestinal disease. This may lead to the development of effective non-immunosuppresive therapies for diseases such as Crohn's disease, enteric infection, ischemia-reperfusion injury, and graft versus host disease. The central hypothesis of this proposal is that IFNgamma and TNFalpha synergize to activate a signaling cascade that results in increased TNF receptor expression, increased MLC kinase expression, increased MLC phosphorylation, tight junction reorganization, and epithelial barrier dysfunction.
The aims of this application are to test this hypothesis by i) determining the role of IFNgamma in enhancing epithelial responsiveness to TNFalpha and the mechanisms by which IFNgamma and TNalpha synergize to increase MLC phosphorylation, ii) defining the effects of IFNgamma and TNFalpha on tight junction protein dynamics using integrated functional, biochemical, and real time imaging approaches, and iii) exploring the effects of IFNgamma and TNFalpha on the regulation of MLC phosphorylation in vivo using knockout mice and pharmacologic agents that prevent IFNgamma / TNFalpha -induced barrier dysfunction in vitro. We expect that these studies will have significant positive effects on human health because they will lead to the development of new understanding of the mechanisms by which barrier function is compromised in disease and will provide the foundation necessary for the development of strategies for enhancement of barrier function as a therapeutic modality.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
3R01DK068271-05S1
Application #
7991912
Study Section
Special Emphasis Panel (ZRG1-DIG-C (02))
Program Officer
May, Michael K
Project Start
2005-07-01
Project End
2010-12-02
Budget Start
2009-12-03
Budget End
2010-12-02
Support Year
5
Fiscal Year
2010
Total Cost
$99,959
Indirect Cost
Name
University of Chicago
Department
Pathology
Type
Schools of Medicine
DUNS #
005421136
City
Chicago
State
IL
Country
United States
Zip Code
60637
Krug, S M; Bojarski, C; Fromm, A et al. (2018) Tricellulin is regulated via interleukin-13-receptor ?2, affects macromolecule uptake, and is decreased in ulcerative colitis. Mucosal Immunol 11:345-356
Odenwald, Matthew A; Choi, Wangsun; Kuo, Wei-Ting et al. (2018) The scaffolding protein ZO-1 coordinates actomyosin and epithelial apical specializations in vitro and in vivo. J Biol Chem 293:17317-17335
Buckley, Aaron; Turner, Jerrold R (2018) Cell Biology of Tight Junction Barrier Regulation and Mucosal Disease. Cold Spring Harb Perspect Biol 10:
Syed, Sana; Yeruva, Sunil; Herrmann, Jeremy et al. (2018) Environmental Enteropathy in Undernourished Pakistani Children: Clinical and Histomorphometric Analyses. Am J Trop Med Hyg 98:1577-1584
Drolia, Rishi; Tenguria, Shivendra; Durkes, Abigail C et al. (2018) Listeria Adhesion Protein Induces Intestinal Epithelial Barrier Dysfunction for Bacterial Translocation. Cell Host Microbe 23:470-484.e7
Sallis, Benjamin F; Erkert, Lena; MoƱino-Romero, Sherezade et al. (2018) An algorithm for the classification of mRNA patterns in eosinophilic esophagitis: Integration of machine learning. J Allergy Clin Immunol 141:1354-1364.e9
Almansour, Khaled; Taverner, Alistair; Turner, Jerrold R et al. (2018) An intestinal paracellular pathway biased toward positively-charged macromolecules. J Control Release 288:111-125
Hu, Madeleine D; Ethridge, Alexander D; Lipstein, Rebecca et al. (2018) Epithelial IL-15 Is a Critical Regulator of ?? Intraepithelial Lymphocyte Motility within the Intestinal Mucosa. J Immunol 201:747-756
Hou, Qihang; Ye, Lulu; Liu, Haofei et al. (2018) Lactobacillus accelerates ISCs regeneration to protect the integrity of intestinal mucosa through activation of STAT3 signaling pathway induced by LPLs secretion of IL-22. Cell Death Differ 25:1657-1670
Odenwald, Matthew A; Choi, Wangsun; Buckley, Aaron et al. (2017) ZO-1 interactions with F-actin and occludin direct epithelial polarization and single lumen specification in 3D culture. J Cell Sci 130:243-259

Showing the most recent 10 out of 103 publications