Cytokines and IBD - University of Connecticut

Cytokines and
Inflammatory Bowel
Alexander Lind
University of Connecticut MCB5255 2014-04-09
Background information about cytokines
Cytokines and IBD
Article 1
Article 2
Future studies, specific aims
and regulation
Involved in
nearly all
Stem cell
Used as
prognostic and
agents in human
Cytokine storm
Pro-inflammatory/ Anti-inflammatory cytokines
Background information about cytokines
Cytokines and IBD
Article 1
Article 2
Future studies, specific aims
Cytokine imbalance
contributes to IBD
Dendritic cell
recruitment and
T-cells differentiation
 Crohn's disease Th1 cell mediated
Ulcerative ColitisTh2 cell mediated
•Th1 cell induced differentiation
mediated by IL-12 and IL-23
•Th2 atypical immune response
•Lack of increased IFN-γ expression
(abundant in CD) rather than the
elevation of IL-4 the Th2-defining
•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
•TH17 cells producing IL-17
•Characterized by enhanced
production of IFN-γ and TNF-α
•TNF-α is upregulated in both
CD and UC
•Mostly produced
by activated
• Transmembrane
protein, activated
through proteolytic
• Play an important
role in the
pathogenesis of
Anticytokine therapies
•Monoclonal anti-TNF-alpha antibodies has 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
Problems with current Anti TNF-α
• 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-TNFα 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
Background information about cytokines
Cytokines and IBD
Article 1
Article 2
Future studies, specific aims
Article 1
“Orally delivered siRNA targeting
macrophage Map4k4 suppresses systemic
inflammation” by Aoudi 2009
Investigates the potential RNA interference to
decrease inflammatory response
Figure 1. Experimental design
Figure 2. Orally delivered Map4k4 siRNA containing vectors can be phagocytized by
macrophages and silence messenger RNA expression
Figure 2. (Continued)
Conclusion: In vitro treatment of Map4k4 siRNA can silence
messenger RNA expression and inhibit LPS induced TNFα
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
Figure 4. Oral
administration of Map4k4
siRNA decreases mRNA
expression in lung, liver
and spleen.
Figure 4. ( Continued)
Conclusion: Demonstrated that macrophages in the gut internalize orally
delivered siRNA, undergo RNA interference mediated gene silencing and
migrate into tissues throughout the body.
Figure 5: What is the effect on TNFα expression after Map4k4
Conclusion:Map4k4-siRNA administration protects mice from LPS-induced
lethality through inhibition of TNF-α in macrophages
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
 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.
Background information about cytokines
Cytokines and IBD
Article 1
Article 2
Future studies, specific aims
Article 2
“Gene silencing of TNF-alpha in a murine model of acute colitis
using a modified cyclodextrin delivery system” by MacCarthy
Investigates possibility of silencing TNF-α trough RNA
interference in IBD
Figure 1. Stability and delivery of siRNA
siRNA has short half-life time in plasma due to nuclease
Cyclodextrin, natural occurring oligosaccharides
Figure 2.Investigation of vector-siRNA complex
stability in simulated intestinal fluids
Figure 3. Quantification
of TNF-α and IL-6
expression in LPS
stimulated cells
Figure 4. Examination of inhibitory
effect of TNF-α siRNA on LPSinduced cytokine secretion and
Conclusion: TNF-α siRNA reduced LPS
induced cytokine expression of TNF-α and
Figure 5. Clinical response after TNF-α siRNA delivery in
DSS treated mice
A trends towards clinincal improvement could be observed
after TNF-α siRNA delivery: increased body weight,
reduced colon weight
Figure 6. Decreased TNF-α and
IL-6 expression in proximal colon
after TNF-α -siRNA delivery to
DSS-treated mice
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
1) clinical improvements of IBD associated features
2) 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
Background information about cytokines
Cytokines and IBD
Article 1
Article 2
Future studies, specific aims
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-α expression
Genecopoeia. Cytokines and Inflammatory Response
• Kindt TJ Kuby Immunologi 6th edition, Figure 12.
• Morens DM The 1918 influenza pandemic: Lessons for 2009 and the future. Critical Care Medicine.
• Osterholm et. al.. Proposed Mechanism of the Cytokine Storm Evoked by Influenza virus. New England Journal of Medicine
• Audet CM et. al. Interplay between pro-inflammatory cytokines and growth factors in depressive illnesses. Cellular neuroscience.
• Melmed GY Future biologic targets for IBD: potentials and pitfalls. Nature Reviews Gastroenterology and Hepatology.
• Monteleone G T-cell-directed therapies in inflamatory bowel diseases. Clinical science.
• Joshua R Evolving knowledge and therapy of inflammatory bowel disase. Nature reviews.
• Sanchez-Munoz Role of cytokines in inflammatory bowel disease. World J Gastroenterology.
• RNA interference. Silence therapeutics.

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