Wheat Amylase Trypsin Inhibitors as Divers of Innate Immunity in ...

Wheat Amylase Trypsin Inhibitors as Divers of
Innate Immunity in Celiac Disease
Detlef Schuppan
Professor of Molecular and Translational Medicine, Dept. Medicine e I,
Univ. of Mainz, Germany
Professor of Medicine, Division of Gastroenterology, Beth Israel Deaconess
Medical Center, Harvard Medical School, Boston, USA
Associazione Italiana Celiachia, , Florence, March 29-31, 2012
HARVARD
MEDICAL
SCHOOL

Hallmarks of celiac disease
• Dietary gluten from wheat, barley, rye
as trigger
• Genetic Predisposition (HLA-DQ2 or –
DQ8)
• IgA autoantibodies to endomysium and
reticulin

Definition of non-celiac gluten sensitivity
Symptoms induced by gluten ingestion in the
absence of 1-3 of the 3 defining hallmarks of
(adapative imunity )of celiac disease
GS patients are orphans living in a (diagnostic and
therapeutic) no man‘s land

„gluten
sensitivity“
without DQ2/8 and
celiac auto-Abs
Verdu EF et al, Am J Gastroenterol 2009

Role of the Innate Immune System in celiac disease – prior work
• Stimulation of biopsies from CD patients with whole gliadin digests or α2
gliadin p31-43 increases the number of IL-15 positive cells within the lamina
propria
(Maiuri
et al, Lancet 2003)
• p31-43 induces MICA on intestinal epithelial cells via IL-15, providing a target
for cytotoxic IELs (Hue et al, Immunity 2004)
• Peptic-tryptic
tryptic gliadin digests and certain gliadin peptides induce activation
and maturation of monocytes, , macrophages and dendritic cells (Tuckova
Tuckova et al, J
Leuk Biol 2002; Palova-Jelinkova
et al, FEBS Lett 2004; Nikulina et al, J Immunol 2004;
Palova-Jelinkova
et al. J Immunol., 2005; Cinova et al, J Clin Immunol 2007; Rakhimova et al.,
J Clin Immunol 2008)
• Gliadin increases intestinal permeability and induces DC activation via MyD88
(implication of CXCR3 on intestinal epithelial cells as gliadin receptor) (Thomas
et al., J Immunol., 2006; Lammert et al, Gastroenterology 2008)
Problems:
1. LPS contamination not strictly ruled out
2. No reproducible identification of a certain (set of) gliadin peptide(s)
3. No receptor identified

The innate immune
response to gluten
gliadin
PAMPs
Major role of professional
APC
Is it all gluten
NKG2D (CD94)
TCR+
MIC-A/B
HLA-E E NKG2A+ TCR+
→ CTL suppression
Bhagat G et al, JCI 2008
NK-like
IL-15
IL-15
CTL
epithelial cell killing,
apoptosis, permeability
potentiation of the adaptive
immune response to gluten
TCR+
CD8+
interferon , perforin
granzyme, FasL
IL-15:
• central growth
factor for
intraepithelial NK
cells and CTL
• major driving force
of clonal T cell
expansion in
refractory sprue &
intestinal T cell
lymphoma
Jabri B et al, Gastroenterology 2000
Maiuri L et al, Lancet 2003
Hue S et al, Immunity 2004
Meresse B et al, Immunity 2004
Rakhimova M et al, J Clin Immunol 2008

Wheat amylase-trypsin
inhibitors (ATIs)) as triggers of innate immunity
Junker Y et al, 2012
HPLC purified extracted
wheat ATI
Oda Y et al, Biochemistry 1997

Purified ATI triggers inflammation via TLR4
5 *
4
3
Monocyte derived DCs
*
*
*
*
3 wildtype
C3H/HeJ
2
TLR4 wt and KO mice fed ATI
2
1
*
*
1
0
0
ATI 50g
LPS and ATI: 2.5 nmol/ mouse
C3H/HeJ: TLR4-/- due to a spontaneous
point mutation
Junker Y et al, 2011

Characteristics and functions of cereal ATIs
• Mr 12-16
16 kDa
• 5 (4) highly conserved S-S bonds
• Conserved 4 helix conformation
• Hydrophobic interaction sites
• Forming mono - tetramers
• Highly resistant to (intestinal(
intestinal) proteolysis
Tatham and Shewry, Clin Exp Allergy 2008

Characteristics and functions of cereal ATIs (2)
• Up to 11 homologues in wheat (CM1-3, 16, 17,
0.19, 0.28, 0.53……
……)
• Tetraploid encodes fewer than hxaploid wheat
(lack of the D chromosome: : CM1, 3b, 7, 0.19, 0.28)
• Pest control (inhibition
of parasite amylase and
trypsin like activities)
• Major wheat allergens (baker‘s asthma),
food
allergy to wheat and barley)
Tatham and Shewry, Clin Exp Allergy 2008

Allergen as TLR4 agonist
2nd allergen
Derp1……
MD2
TLR4
MD2-mimetics:
Derp2, ATI
ATI
Derp1
Derp2
from house
dust mite
CD23+
IgE
Allergy
IL-4, IL-13
Th2
IL-6
Rantes
IRF3
MCP-1
IL-8
TLR4 mediated potentiation
of Th1 or allergic responses
NFkB
TNFα, , IL-12,
IL-15
Th1
modified from
Trompette A et al, Nature 2009
Wills-Karp M et al, Mucosal Immunol 2010

Origin of Wheat
Increase of content of immunogenic epitopes and ATI with higher ploidity

Celiac disease
Cd is the best defined and most frequent intestinal (auto-)
immune disease, with gluten (and ATI) as triggers, HLA-
DQ2 (DQ8) as necessary genetic predisposition and TG2
as patho-genetically
linked autoantigen
Most cases are not associated with diarrhea or overt
malabsorption, but are silent or atypical
Disease severity depends on 1. gluten dose, 2. HLA-
DQ2(DQ8)-gene dose, 3. innate immunity (triggered
by
ATIs), , 4. 4
. additional polygenetic and environmental factors
Innate immunity to cereal ATI likely impacts other
intestinal inflammatory diseases