Triggering Thyroid Autoimmunity: Genes,
Viruses, and Epigenetics
Yaron Tomer, MD
Division of Endocrinology, Department of Medicine, Icahn
School of Medicine at Mount Sinai, New York
Nothing to Disclose PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Genes
Viruses
Interactions
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Genes
Viruses
Interactions
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
HLA-DRb1-Arg74
CTLA-4
PTPN22
Tg
ARID5B GD HT
TSHR
CD40
CD25
12q
(BTG1)
Reviewed in:
Tomer. Thyroid 2010; 20: 715-725
Huber, et al. Endocr Rev 2008; 29: 697-725
Brand, Gough, Curr Genomics 2011; 12: 526-541 PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Tg, TSHR
B-cell
Translational Implications
+
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Genes
Viruses
Interactions
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Country Year Patients Controls P-value Study No. %TAb’s No. %TAb’s
France 1993 72 12.5 60 1.7 0.02 Tran
Japan 1994 109 9.2 -- -- -- Watanabe
Spain 1995 96 5.2 96 8.3 NS Boadas
Italy 1995 75 10.7 -- -- -- Carella
UK 1997 111 4.5 99 11.1 NS Metcalfe
Italy 1999 86 9.3 1147 17.1 NS Loviselli
France 2000 97 13.4 97 3.1 0.02 Ganne-Carrie
Italy 2004 630 21 389 12 0.0001 Antonelli
Hepatitis C and Thyroiditis
Reviewed in: Mandac, Chaudhry, Sherman, and Tomer. Hepatology; 2006; 43: 661-672 PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
How can HCV infection
trigger thyroiditis?
Can HCV infect human thyroid cells
Non-specific effects of the virus
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Detection of HCV-RNA in the thyroid
by in-situ hybridization
Bartolome et al J Med Virol 2008; 80: 1588-1594 PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Control – PS cells
Control – PS supernatant
Control – NS cells
Control – NS supernatant
NS sup: uninfected
NS supernatant: infected
NS cells: uninfected
NS cells: infected
PS sup: uninfected
PS cells: uninfected
PS cells: infected
PS sup: infected
295 bp 295 bp
ML-1 Huh7.5
Blackard et al.
Thyroid 2013;
23: 863-870 PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
HCV Infection in the Presence or Absence of anti-CD81
0.00
0.25
0.50
0.75
1.00
0.00
0.25
0.50
0.75
1.00
Huh 7.5
ML-1
Blackard et al. Thyroid 2013; 23: 863-870
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Exposure of cryptic Ag’s
Alteration of self Ag’s
Inflammatory response
Secretion of cytokines (IL-8)
Mechanisms of induction of Thyroiditis by HCV: Bystander Activation
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Genes
Viruses
Interactions
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Non-coding effects on gene expression/function that
are mitotically stable (i.e. long lasting)
• DNA methylation
• Histone modifications
• microRNA activation
Epigenetics: Definition
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Non-coding effects on gene expression/function that
are mitotically stable (i.e. long lasting)
• DNA methylation
• Histone modifications
• microRNA activation
Epigenetics: Definition
Which environmental factor triggers epigenetic
changes in thyroid cells? PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Interferon and AITD
• IFN is a key cytokine secreted during infections
• IFN therapy has been associated with autoimmunity –
AITD, type 1 DM, SLE
• Transgenic mice expressing IFN in thyroid develop thyroiditis
IFN is a Key Cytokine Triggering AITD Akeno. J Immunol 2011; 186: 4693-4706
Tomer. J Autoimmun 2010; 34: J322-J326
Stewart . Science 1993; 260: 1942-1946
Eisenbarth. Clin Immunol 2004; 111: 225-233
Diana. Nat Med 2013; 19: 65-73 PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
IFNa
Human Thyroid Cells
Epigenetic Effects of IFNa
Global histone modifications
H3K4me1 H3K4me3
Genetic Variants
Associated with AITD
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Tg Promoter
rs180195
IFNa +
IFNa -
AAA(A/G)GAAA
Exon 1
TSS
ATG TATA CAAT
40
cAMP-RE
1623
A Tg Promoter SNP That is Associated with AITD
Shows Enrichment in H3K4me1
Stefan et al. JBC 2011; 286; 31168-31179 PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
183
120
173
TG (-1623 G)
HLA-B promoter
TSHR promoter
Tg Promoter -1623 G Allele Binds IRF-1
Stefan et al. JBC 2011; 286; 31168-31179 PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
TG proximal promoter
H3K4me3
H3K4me1
TG -1623 G
H3Ac Active
Chromatin
Active
Transcriptional
Element
Active
Chromatin
Enhancer
Element
Binding of IRF-1 to the -1623 G-Allele Induces
Epigenetic Changes Driving TG Transcription
Stefan et al. JBC 2011; 286: 31168-31179 PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Luciferase Activity
0 5 10 15 20 25 30
p=0.007
p=0.008
pGL4.10-TG (A)
pGL4.10-TG (G)
pGL4.10-TG (del)
Construct
Tg Promoter -1623 G Allele Increases
Promoter Activity
Stefan et al. JBC 2011; 286: 31168-31179 PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Fo
ld c
ha
ng
e
IFNα conc. (U/ml)
1000 5000 10,000 0
TG
IFNα conc. (U/ml)
Fo
ld c
ha
ng
e
IRF-1
0
0.5
1
1.5
2
2.5
3
0 1000 5000 10,000
**
*
*
0
0.5
1
1.5
2
2.5
*
* *
Interferon Induces Tg Expression in Thyroid Cells
How can upregulation of Tg trigger AITD? PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
MECHANISM
Infection
Tg
ER
Stress
PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)
Mihaela Stefan
Erlinda Concepcion
Angela Lombardi
Francesca Menconi
Cheuk Wun Li
Nagako Akeno
Eric Jacobson
Alia Hasham
Molecular Modeling
Roman Osman
Taiji Oashi
Collaborators
Proteomics
Rong Wang
Bioinformatics
Weijia Zhang
Lucy Skrabanek
Statistical Genetics
David Greenberg
Susan Hodge
Cristina Monti
Next gen Sequencing, Genotyping
Mehdi Keddache
Small molecule screening
Dan Felsenfeld PRESENTATION FROM THE 83rd ANNUAL MEETING OF THE AMERICAN THYROID ASSOCIATION, OCTOBER 16-20, 2013 (Yaron Tomer)