APECED: monogenic autoimmune disease

Transcription

1 APECED: monogenic autoimmune disease Pärt Peterson University of Tampere, Finland University of Tartu, Estonia

2 APS1 or APECED APS1 (autoimmune polyendocrine syndrome type 1) or APECED (autoimmune polyendocrinopathy candidiasis ectodermal dystrophy) Autosomal recessive inheritance More prevalent in some populations such as Finns (1:25000), Iranian Jews (1:9000) and Sardinians (1:14400). Very high incidence (1/4400) reported in a small town Bassa del Grappa, in Northern Italy No HLA association Autoimmune regulator (AIRE) is a gene mutated in APECED

3 Clinical Features Endocrinopathies Hypoparathyreoidism Addison s disease Gonadal dysfunction Type 1 diabetes mellitus Autoimmune thyroiditis Autoimmune gastritis Chronic mucocutaneous candidiasis Ectodermal dystrophies dental enamel nails alopecia vitiligo Autoimmune hepatitis Keratopathy

4 Candida infection and vitiligo of APS1 patient From Prof. Olle Kämpe, Uppsala University

5 APS1/APECED and APS2 are two different syndromes Disease components APS1 APS2 Addison s disease Hypoparathyroidism absent Chronic candidiasis absent Ectodermal dysplasia absent Autoimmune thyroid disease Type 1 diabetes Hypogonadism Alopecia Vitiligo Keratopathy absent Autoimmune hepatitis Pernicious anemia Chronic gastritis 6 11

6 Autoantigens in Addison s disease Steroid 17a-hydroxylase, P450c17 Steroid 21-hydroxylase, P450c21 Side-chain cleavage enzyme, P450scc Thomas Addison All three P450 enzymes are active in steroidogenesis in adrenal cortex. P450c21 is expressed only in adrenal cortex, P450c17 and P450scc are also expressed in gonads Krohn et al. Lancet 339: 770, 1992 Uibo et al. JCEM 78: 323, 1994

7 APS1/APECED autoantigens Autoantigen Prevalence % Steroid 21 hydroxylase (P450c21) 66 Side-chain cleavage enzyme (P450scc) 52 Steroid 17 alpha hydroxylase (P450c17) 44 Aromatic L-amino acid decarboxylase (AADC) 51 Glutamic acid decarboxylase (GAD65) 37 Histidine decarboxylase (HDC) 37 Cysteine sulfinic acid decarboxylase (CSAD) 3.6 Tryptophan hydroxylase (TPH) 45 Tyrosine hydroxylase (TH) 44 Thyroglobulin (TG) 36 Thyroid peroxidase (TPO) 36 Transcription factor SOX10 22 Cytochrome P4501A2 (P4501A2) 8 Tyrosine phosphatase-like protein IA-2 (IA-2) 7

8 AIRE protein N-terminal HSR domain: homodimerisation SAND domain: putative DNA binding PHD finger: transcriptional regulation Proline rich region LXXLL motif: binding to nuclear receptors Nagamine et al. Nat Genetics 17: 393, 1997 The Finnish-German Consortium. Nat Genetics 17: 399, 1997

9 Similarity to Nuclear Proteins Mi-2: TIF1: helicase, involved in chromatin remodelling, autoantigen in dermatomyositis transcriptional coactivator Sp100: interferon responsive, transcription activator, autoantigen in PBC, lymphoid restricted Sp140: homologous protein to Sp100, autoantigen in PBC

10 Expression in the Thymus The major AIRE expressing tissue is the thymus Lower levels of expression are seen in the fetal liver, spleen and lymph nodes In the thymus, AIRE is seen in a distinct subset of cells in situ hybridisation Anti-AIRE ab Heino et al. BBRC 257: 821, 1999

11 Subcellular localization Aire localizes to nuclear dots in thymus medulla and in transfected Cos cells

12 Human and Mouse AIRE proteins are 77% identical aa PRR (23.5%) aa AIRE L L NLS HSR/ASS SAND PHD L PHD L Aire L HSR/ASS L NLS SAND PHD PRR (16%) L PHD L mouse : MAGGDGMLRRLLRLHRTEIAVAIDSAFPLLHALADHDVVPEDKFQETLRLKEKEGCPQAFHALLSWLLTRDSGAILDFWRILFKDYNLERYSRLHSILDGFPKDVDLNQSR : 111 human : MA-TDAALRRLLRLHRTEIAVAVDSAFPLLHALADHDVVPEDKFQETLHLKEKEGCPQAFHALLSWLLTQDSTAILDFWRVLFKDYNLERYGRLQPILDSFPKDVDLSQPR : 110 L mouse : KGRKPLAGPKAAVLPPRPPTKRKALEEPRATPPATLASKSVSSPGSHLKTKPPKKPDGNLESQHLPLGNGIQTMAASVQRAVTVASGDVPGTRGAVEGILIQQVFESGRSK : 222 human : KGRKPPAVPKALVPPPRLPTKRKASEEARAAAPAALTPRGTASPGSQLKAKPPKKPESSAEQQRLPLGNGIQTMSASVQRAVAMSSGDVPGARGAVEGILIQQVFESGGSK : 221 NLS mouse : KCIQVGGEFYTPNKFEDPSGNLKNKARSGSSLKPVVRAKGAQVTIPGRDEQKVGQQCGVPPLPSLPSEPQVNQKNEDECAVCHDGGELICCDGCPRAFHLACLSPPLQEIP : 333 human : KCIQVGGEFYTPSKFED-SGSGKNKARSSSGPKPLVRAKGAQGAAPGGGEARLGQQGSVPAPLALPSDPQLHQKNEDECAVCRDGGELICCDGCPRAFHLACLSPPLREIP : 331 SAND mouse : SGLWRCSCCLQGRVQQNLSQPEVSRPPELPAETPILVGLRSASEKTRGPSRELKASSDAAVTYVNLLAPHPAAPL--LEPSALCPLLSAGNEGRPGPAPSARCSVCGDGTE : 442 human : SGTWRCSSCLQATVQEVQPRAEEPRPQEPPVETPLPPGLRSAGEEVRGPPGEPLAGMDTTLVYKHLPAPPSAAPLPGLDSSALHPLLCVGPEGQQNLAPGARCGVCGDGTD : 442 mouse : VLRCAHCAAAFHWRCHFPTAAARPGTNLRCKSCSADSTPTPGTPGEAVPTSGPRPAPGLAKVGDDSASHDPVLHRDDLESLLNEHSFDGILQWAIQSMSRPLAETPPFSS : 552 human : VLRCTHCAAAFHWRCHFPAGTSRPGTGLRCRSCSGDVTPAP-VEGVLAPSP-ARLAPGPAK--DDTASHEPALHRDDLESLLSEHTFDGILQWAIQSMARPAA---PFPS : 545 PHD ASS L L L PHD Mittaz et al. BBRC, 255: 483, 1999

13 Aire co-localizes with epithelial cell markers in thymus medulla MTS5 MTS10

14 Thy CD8 + DC Thy CD8 lo/- DC Spl CD DC Spl CD4-8 - DC Spl CD4-8+DC Thymocytes Spl macroph. AIRE is expressed in Dendritic cells Aire β-actin Several subclasses of mouse dendritic cells express Aire AIRE mrna is upregulated in vitro stimulated human DCs

15 Cortex Thymocyte differentiation Double negative CD4- CD8- No T-cell receptor Medulla Double positive CD4+ CD8+ T-cell receptor Single positive CD4+ CD8- or CD4- CD8+ T-cell receptor

16 Thymocytes are selected differentially according to their reactivity TCR reactive to non-self antigens T-cell precursor Cells survive and when meeting pathogen will proliferate TCR reactive to self antigens Cell death

17 Autoimmune diseases and autoantigens Addison s disease Autoimmune gastritis Pernicious anemia Hashimoto thyroiditis Graves disease Myasthenia gravis Type 1 diabetes Vitiligo Rheumatoid arthritis Multiple sclerosis steroid P450 cytochromes H + /K + ATPase intrinsic factor thyroid peroxidase, thyroglobulin thyroid receptor Acetylcholine receptor insulin, GAD65 tyrosinase, MART type 2 collagen myelin basic protein

18 Ectopic (promiscuous) expression of self antigens in thymus Many tissue specific autoantigens are expressed in thymus. During negative selection, T- cells to these antigens are deleted. If antigen is not expressed in thymus or is expressed in a different way, this may cause autoimmunity From Gotter et al. 2004

19 Diverse genes expressed in thymic epithelial cells Tissues specific antigens (pancreas, stomach, brain, eye, liver, muscle, kidney specific genes) Expression of genes expressed during fetal stages, pregnancyassociated genes Expression of male specific genes in females and vice versa Expression of cancer specific antigens Conserved in mice and humans Estimation of 3000 genes (5-10% of known genes) in addition to basal expression of thymic epithelial cells

20 AIRE (autoimmune regulator) gene is central in expressing tissue specific antigens

21 Aire deficient mice have autoantibodies and lymphocytic infiltration in multiple tissues Anderson et al. Science, 2002

22 Microarray analysis of gene expression in wild-type and Aire deficient mouse The expression of tissue specific genes is lower or non-existing in Aire deficient mouse Anderson et al. Science, 2002

23 The PHD zinc fingers form the activation domain of AIRE HSR NLS SAND PHD PRR PHD

24 AIRE Interacts with CBP AIRE binds CBP at its CH1 and CH3 domains by far western and yeast two-hybrid assays CH1 also binds STAT2 and HIF-1a; CH3 binds E1A and TFIIB

25 CBP: camp response element binding (CREB) protein binding protein CBP is implicated in various transcriptional responses regulating growth, differentiation or apoptosis Belongs to the class of transcription co-activators possessing histone acetyltransferase activity (HAT) and thus have the potential to regulate the chromatin structure CBP/p300 interacts with many transcription activators and coactivators From Hottiger and Nabel, 2000

26 AIRE Colocalises with CBP AIRE CBP merge

27 3D picture of AIRE dots Nuclear Bodies Most prominent nuclear bodies are promyelocytic leukemia (PML) nuclear body or POD (PML oncogenic domain) Approximately 0.3 to 1 micrometers in diameter Other proteins in nuclear dots are involved in transcription or suspected in chromatin binding (Sp100, CBP, BLM, p53) Function unknown, activation or degradation site? Some of the proteins like CBP move in and out.

28 AIRE Function AIRE induces the expression of autoantigens that lead to the elimination of the autoreactive T cells T cell autoreactive to APECED autoantigen Thymus AIRE Thymic epithelial cell expressing autoantigens

29 Loss of Function When AIRE is defective, autoreactive T cells escape selection, and autoimmunity develops T cell autoreactive to APECED autoantigen Thymus No AIRE Thymic epithelial cell expressing autoantigens

30 University of Tampere Jukka Pitkänen Camelia Magureanu Ulla Aapola Niko Sillanpää Astrid Murumägi Maarit Heino Pärt Peterson Kai Krohn WEHI, Melbourne Hamish Scott Li Wu University of Tokushima Mitsuru Matsumoto Keio University, Tokyo Jun Kudoh Nobuyoshi Shimizu University of Würzburg Philipp Ströbel Alex Marx University of Geneva Laureane Mittaz Stylianos Antonarakis University of Birmingham Graham Anderson Eric Jenkinson

31 University of Tartu Ana Rebane Vivian Kont Kaidi Möll Tõnis Org Ingrid Liiv Eneli Õis Annika Reimets Rainis Venta Mario Saare