1 / 36

C ytokines and I nflammatory B owel D isease

C ytokines and I nflammatory B owel D isease. Alexander Lind University of Connecticut MCB5255 2014-04-09. Overview. Background information about cytokines Cytokines and IBD Article 1 Article 2 Future studies, specific aims. Cytokines. Cell communication and regulation

flint
Download Presentation

C ytokines and I nflammatory B owel D isease

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cytokines and Inflammatory Bowel Disease Alexander Lind University of Connecticut MCB5255 2014-04-09

  2. Overview • Background information about cytokines • Cytokines and IBD • Article 1 • Article 2 • Future studies, specific aims

  3. Cytokines • Cell communication and regulation • Involved in nearly all biological processes: • Embryonic development • Stem cell differentiation • Inflammatory responses • Used as prognostic and therapeutic agents in human disease http://www.genecopoeia.com/product/search/pathway/h_inflamPathway.php

  4. Cytokine storm http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3180813/ http://www.cytokinestorm.com/

  5. Pro-inflammatory/ Anti-inflammatory cytokines

  6. Overview • Background information about cytokines • Cytokines and IBD • Article 1 • Article 2 • Future studies, specific aims

  7. Cytokine imbalance contributes to IBD through: • Macrophage, Dendritic cell recruitment and activation • T-cells differentiation • Crohn's disease - Th1 cell mediated response • Ulcerative Colitis- Th2 cell mediated response http://www.nature.com/nrgastro/journal/v7/n2/fig_tab/nrgastro.2009.218_F1.html

  8. ULCERATIVE COLITIS Th2 atypical immune response Lack of increased IFN-γ expression (abundant in CD) rather than the elevation of IL-4 the Th2-defining cytokine Classical pro-inflammatory cytokines, such as IL-1, IL-6, and TNF-α Th2 cytokines IL-10 and IL-13 play a key role,  increased IL-13 production by NKT cells Crohn's disease • Th1 cell induced differentiation mediated by IL-12 and IL-23 • TH17cells producing IL-17 • Characterized by enhanced production of IFN-γ and TNF-α http://www.nature.com/nrd/journal/v5/n3/fig_tab/nrd1986_ft.html http://www.clinsci.org/cs/118/0707/cs1180707f03.htm

  9. TNF-α • TNF-α is up-regulated in both CD and UC • Mostly produced by activated macrophages • Transmembrane protein, activated through proteolytic cleavage • Play an important role in the pathogenesis of IBD http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2731177/

  10. Anticytokine therapies • Monoclonal anti-TNF-alpha antibodieshas showed good results in both inducing and maintaining remission • Do not act only by neutralizing TNF-alpha: • Induce monocyte and T-cell apoptosis • Antibody-dependent cell-mediated cytotoxicity • Unclear why certain anti-TNF therapies are effective in IBD where as other are not

  11. Problems with current Anti TNF-αtherapies • Liver Injury Secondary to Anti-TNF-Alpha Therapy in Inflammatory Bowel Disease: A Case Series and Review of the Literature. Parekh et. al. 2014 • Incidences of serious infections and tuberculosis among patients receiving anti-tumor necrosis factor-α therapy. Yoo et. al 2014 • Recurrence of active tuberculosis following resumption of anti-TNF-α therapy in a patient with Crohn's disease. Masia et. al. 2014 • Tuberculosis infection following anti-TNF therapy in inflammatory bowel disease, despite negative screening. Debeuckelaere et. al. 2013 • Immune-mediated inflammatory reactions and tumors as skin side effects of inflammatory bowel disease therapy Marzano et. al. 2014

  12. Overview • Background information about cytokines • Cytokines and IBD • Article 1 • Article 2 • Future studies, specific aims

  13. Article 1 • “Orally delivered siRNA targeting macrophage Map4k4 suppresses systemic inflammation” by Aoudi et.al. 2009 • Investigates the potential RNA interference to decrease inflammatory response

  14. http://silence-therapeutics.com/platform-technologies/rna-interference/http://silence-therapeutics.com/platform-technologies/rna-interference/

  15. Figure 1. Experimental design

  16. Figure 2. Orally delivered Map4k4 siRNA containing vectors can be phagocytized by macrophages and silence messenger RNA expression

  17. Figure 2. (Continued) Conclusion: In vitro treatment of Map4k4 siRNA can silence messenger RNA expression and inhibit LPS induced TNFαproduction.

  18. Figure 3: What effect does Map4k4 silencing have on LPS activation of previously known pathways for regulation of Tnf-α production? Conclusion: Map4k4 is a new target for suppression of Tnf-α expression, activation occurs independently of previously known pathways

  19. Figure 4. Oral administration of Map4k4 siRNA decreases mRNA expression in lung, liver and spleen.

  20. Figure 4. ( Continued) Conclusion: Demonstrated that macrophages in the gut internalize orally delivered siRNA, undergo RNA interferencemediated gene silencing and migrate into tissues throughout the body.

  21. Figure 5: What is the effect on TNF-αexpression after Map4k4 silencing? Conclusion:Map4k4-siRNA administration protects mice from LPS-induced lethality through inhibition of TNF-α in macrophages

  22. Conclusions from article 1 • The results in this articles describes a new strategy for oral delivery of siRNA to weaken inflammatory responses in human disease • Identification of Map4k4, a previously unknown mediator of cytokine expression. • Silencing of Map4k4 in macrophages in vivo protected mice from lipopolysaccharide-induced lethality by inhibiting of TNF-α This article demonstrated promising results for anti-TNF-α protein therapeutics. Development of GeRP-mediated delivery of siRNA show promising results as inflammatory decreasing agents for several disease including IBD.

  23. Overview • Background information about cytokines • Cytokines and IBD • Article 1 • Article 2 • Future studies, specific aims

  24. Article 2 • “Gene silencing of TNF-alpha in a murine model of acute colitis using a modified cyclodextrin delivery system” by MacCarthy et.al. 2013 • Investigates possibility of silencing TNF-α trough RNA interference in IBD

  25. Figure 1. Stability and delivery of siRNA • siRNA has short half-life time in plasma due to nuclease degradation • Cyclodextrin, natural occurring oligosaccharides http://pubs.rsc.org/en/content/articlepdf/2010/MB/C001050M

  26. Figure 2.Investigation of vector-siRNA complex stability in simulated intestinal fluids

  27. Figure 3. Quantification of TNF-α and IL-6 expression in LPS stimulated cells

  28. Figure 4. Examination of inhibitory effect of TNF-α siRNA onLPS-induced cytokine secretion and expression Conclusion: TNF-α siRNA reduced LPS induced cytokine expression of TNF-α and IL-6

  29. Figure 5. Clinical response after TNF-αsiRNA delivery in DSS treated mice A trends towards clinincal improvement could be observed after TNF-αsiRNAdelivery: increased body weight, reduced colon weight

  30. Figure 6. Decreased TNF-α and IL-6 expression in proximal colon after TNF-α -siRNA delivery to DSS-treated mice

  31. Conclusions from Article 2 • Showed in vitro studies that delivery of TNF-α siRNA could interfere with LPS induced activation of pro-inflammatory cytokines • Intrarectal administration of TNF-siRNA in DSS-treated mice gave indications of: • clinical improvements of IBD associated features • Lower expression of TNF-α and IL-6 in proximal colon This article demonstrated promising results of a CD-based siRNA delivery system for silencing of pro-inflammatory cytokine TNF-α. Potentially used in future treatment of IBD.

  32. Overview • Background information about cytokines • Cytokines and IBD • Article 1 • Article 2 • Future studies, specific aims

  33. Future studies • There is a problem with side effects using current therapies • RNA interference silencing Mp4k4 and TNF-α show promising results • Combination of silence several genes? Other ways affecting TNF-α expression? Specific aim: To use RNA interference technique to try and silence gene expression of transcription factor LITAF known to regulate TNF-αexpression

  34. References • Genecopoeia. Cytokines and Inflammatory Response http://www.genecopoeia.com/product/search/pathway/h_inflamPathway.php • Kindt TJ et.al.. KubyImmunologi 6th edition, Figure 12. • Morens DM et.al. The 1918 influenza pandemic: Lessons for 2009 and the future. Critical Care Medicine. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3180813/ • Osterholm et. al.. Proposed Mechanism of the Cytokine Storm Evoked by Influenza virus. New England Journal of Medicine http://www.cytokinestorm.com/cytokine_storm.html • Audet CM et. al. Interplay between pro-inflammatory cytokines and growth factors in depressive illnesses. Cellular neuroscience. http://journal.frontiersin.org/Journal/10.3389/fncel.2013.00068/full • Melmed GY et.al. Future biologic targets for IBD: potentials and pitfalls. Nature Reviews Gastroenterology and Hepatology. http://www.nature.com/nrgastro/journal/v7/n2/fig_tab/nrgastro.2009.218_F1.html • MonteleoneG et.al. T-cell-directed therapies in inflamatory bowel diseases. Clinical science. http://www.clinsci.org/cs/118/0707/cs1180707f03.htm • Joshua R et.al. Evolving knowledge and therapy of inflammatory bowel disase. Nature reviews. http://www.nature.com/nrd/journal/v5/n3/fig_tab/nrd1986_ft.html • Sanchez-Munoz et.al. Role of cytokines in inflammatory bowel disease. World J Gastroenterology. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2731177/ • RNA interference. Silence therapeutics. http://silence-therapeutics.com/platform-technologies/rna-interference/

More Related