Transcript Nertila_Ujkaj:Littin_Kandoth_Sandra

The Role of
TCR gamma-delta T cells in
Celiac Disease
By: Nertila Ujkaj
Littin Kandoth
Sandra
Mentor: Dr. Manavalan
Columbia University, College of Physicians and Surgeons
Celiac disease (CD)
•a digestive disease that damages the small intestine
and interferes with absorption of nutrients from food.
•when people with CD consume gluten, their immune
system responds by damaging the small intestine
•a genetic disorder
•symptoms: diarrhea, weight loss, malnutrition, etc…
•diagnosis is done by intestinal biopsy histological
grading and presence of serum auto- antibodies.
•CD is considered an autoimmune disorder because the
body's own immune system causes the damage
The Gut Lumen
IFN-g & Cytotoxic granules
IMMUNOPATHOGENESIS OF
CELIAC DISEASE
Gluten
?
MICA/B
NKG2D
CD94/NKG2C
IEL
gd T cell
IEL
ab T cell
INTRAEPITHELIAL SPACE
Gliadin
Peptide
IL-15
IL-15
LAMINA PROPRIA
HLA-DQ2
or DQ8
Antigen
Presenting
Cell
LP
CD4+
T cell
B cell
Anti-gliadin and
anti-TTG2
antibodies
Objective
• To determine if the TCR gamma-delta IELs in patients with
CD are Regulatory/Suppressor T cells
– Regulatory T cells (also known as suppressor T cells) are a
specialized subpopulation of T cells that act to suppress
activation of the immune system and thereby maintain
immune system homeostasis and tolerance to self.
– They are characterized by having some of the following
markers
•Intracellular FOXP3
•TGF-beta
•IL-10
•CTLA 4
•GITR
Methods
• Isolation of Lymphocytes from the Duodenal biopsies of 30 patients with Celiac
Disease
• Immunostaining for the following extracellular and intracellular markers:
– T-Cell markers
• CD3
• CD8
• TCR alpha-beta
• TCR-gamma-delta
– Markers for Regulatory/Suppressor cells:
• Intra-cellular FOXP3
• Intracellular TGF-beta
• GITR
• CTLA-4
• Intra-cellular IL-10
• Flow cytometry- technique for counting, examining and sorting microscopic
particles (such as cells) suspended in a stream of fluid
http://www.flow-cytometry.de/img/fcm.gif
A. Immunohistochemistry
B. Flow Cytometry
EPITHELIAL CELLS
INTRAEPITHELIAL LYMPHOCYTES (IEL)
Results
Results
Results
Means (error bars: 95% CI for mean)
45
35
30
25
20
15
10
5
50
% Intracellular TGF-beta expressing cells
40
Means (error bars: 95% CI for mean)
40
30
20
10
0
0
TCR alpha-beta
TCR gamma-delta
TCR alpha-beta
TCR gamma-delta
IFN-g & Cytotoxic granules
Gliadin
MICA/B
NKG2D
CD94/NKG2C
TTG
IL-15
IEL
ab T cell
TGFb
IEL
gd T cell
FOXP3
IL-15
HLA-DQ2/8
Antigen
Presenting
Cell
LP
CD4+
T cell
B cell
Anti-gliadin and
anti-TTG2
antibodies
Conclusion
• The TCR gamma-delta T cells have FOXP3 and secrete
TGF-beta and are probably Regulator/ Suppressor T
cells
Future studies
• To prove that TCR gamma delta T cells can suppress the
immune response
• To determine if CD patients who are on therapy have
more suppressor TCR gamma-delta T cells than Active
CD patients
References
•
Green, P.H. and B. Jabri, Celiac disease. Annu Rev Med, 2006. 57: p. 207-21.
•
Shan, L., et al., Structural basis for gluten intolerance in celiac sprue. Science, 2002. 297(5590): p. 2275-9.
•
Meresse, B., et al., Coordinated induction by IL15 of a TCR-independent NKG2D signaling pathway
converts CTL into lymphokine-activated killer cells in celiac disease. Immunity, 2004. 21(3): p. 357-66.
•
Chen, Y., et al., Protection of the intestinal mucosa by intraepithelial gamma delta T cells. Proc Natl Acad
Sci U S A, 2002. 99(22): p. 14338-43.
•
Peng, S.L., et al., Propagation and regulation of systemic autoimmunity by gammadelta T cells. J Immunol,
1996. 157(12): p. 5689-98.
•
Roncador, G., et al., Analysis of FOXP3 protein expression in human CD4+CD25+ regulatory T cells at the
single-cell level. Eur J Immunol, 2005. 35(6): p. 1681-91.
•
Manavalan, J.S., et al., Alloantigen specific CD8+CD28- FOXP3+ T suppressor cells induce ILT3+ ILT4+
tolerogenic endothelial cells, inhibiting alloreactivity. Int Immunol, 2004. 16(8): p. 1055-68.
Acknowledgements
•Dr. Manavalan
•Dr. Sat Bhattacharya
•Harlem Children Society
•Allison
•Shannon
•Harold
•Celiac Disease Center of Columbia University
Thank You!!!