12th prac*ce: Autoan*body diagnos*cs

Transcription

1 12th prac*ce: Autoan*body diagnos*cs Basic Immunology University of Pécs, Clinical Center Department of Immunology and Biotechnology Pécs, 2016.

2 Autoimmunity Autoimmunity: Recogni*on and immune response to self-an(gens. Natural autoimmunity Pathological autoimmunity Has immunoregulatory role An*body produc*on without external s*muli Natural autoan(bodies: Low affinity Polyspecific Mainly IgM Low serum concentra*ons Produced by B1 B cells Causes or is associated with pathological condi*ons Pathological autoan(bodies: High affinity Monospecific Mainly IgG High serum concentra*ons Produced by B2 B cells

3 B1 B cells Self-renewal on the periphery Natural autoan*bodies (IgM) Marginal zone B cells B2 B cells Follicular B cells IgM IgM Germinal center reac*on Memory B cells Survival in the bone marrow IgG IgA IgE

4 Targets of natural autoan*bodies Evolu(onary conserved structures that are usually found in all cells, e.g.: Heat shock proteins Proteins of the cytoskeleton Metabolic enzymes Nuclear structures Hypothesized role: Maintaining immunological tolerance, removal of self-an*gens (e.g. DAMP: Damage-associated molecular paxern), preven*on of pathological autoimmunity Natural autoan*bodies are cons*tu*vely present and their repertoires are constant, independent of age or gender and characteris(c for each individual. Immunological homunculus or Immunculus

5 Removal of apopto(c material B1 B cells Preven(on of autoimmunity (Elimina(on of DAMPs) Natural autoan(bodies Immune regula(on and homeostasis

6 Removal of apopto*c bodies Opsoniza*on of apopto(c bodies, phagocytosis via Fc and complement receptors. MBL C1q CR IL-10, TGFβ APOPTOTIC BODY IgM FcR PHAGOCYTE

7 Autoimmune disorders They affect 7-8% of the popula*on. Have a strong female dominance. (e.g. the male:female ra*o in SLE is 1:9) Many affect young adults. Can occur jointly in the same pa*ent. Polyautoimmunity (e.g. a second autoimmune disease occurs in 41% of all pa*ents with SLE) They are chronic illnesses! Their development: Gene(cs Gender Pathogens B cell Autoimmune disease Life style (smoking, diet) Autoan(bodies, abnormal cytokine produc(on Phenotype, Polyautoimmunity Epigene(cs T cell TCR Hereditary factors Environmental factors Preclinical autoimmunity Manifest disease Time

8 Molecular mimicry The pathogen s an*gen shares a high degree of structural similarity with selfan*gens. Can lead to cross-reac(on and autoimmunity in gene*cally suscep*ble people. (e.g. rheuma*c fever ader Streptococcus pyogenes infec*ons) Pathogen with An(gen A Own (ssues with self-an(gen that resemble an(gen A Crossreac(ve T cell Crossreac(ve an(bodies Crossreac(ve B cell

9 Forma*on of neoan*gens Gliadin (component of gluten) Tissue transglutaminase Deamidated gliadin pep(de ttg + gliadin complex = NEOANTIGEN Deamida(on An(gen presenta(on to Th cells (HLA-DQ2 or HLA-DQ8) An(-tTG autoan(bodies in celiac disease

10 Loss of central tolerance Normal Thymus AIRE muta(on Thymus AIRE AIRE Nega(ve selec(on Autoreac*ve T cells released to the periphery APECED (Autoimmune polyendocrinopathycandidiasis - ectodermal dystrophy)

11 Classifica*on of autoimmune diseases Systemic diseases (Affect the en*re body) Autoimmune disorders (see in the clinical phase) Organ-specific diseases (Affect a specific organ) Rheumatoid arthri*s Addison s disease Myasthenia gravis Scleroderma (Systemic sclerosis) SLE (Systemic lupus erythematosus) Graves-Basedow disease

12 Organ-specific autoan*bodies Occur in organ-specific autoimmune diseases. Some examples of the targets of organ-specific autoan*bodies: Type I diabetes mellitus (IDDM): glutamic acid decarboxylase (GAD), tyrosine phosphatase-like protein (IA-2) Autoimmune thyroid diseases: thyroperoxidase (TPO), thyroglobulin Goodpasture syndrome: type IV collagen (basal membrane in the glomeruli and the lung) Myasthenia gravis: postsynap*c nico*nic acetylcholine receptors (neuromuscular junc*on) Celiac disease: (ssue transglutaminase (ttg), endomysium, gliadin (the laxer is a component of gluten found in cereals and therefore is not an autoan*gen!) Primary biliary cirrhosis: several mitochondrial an*gens Detec*on of such autoan*bodies can be diagnos(c and also have prognos(c significance. Their levels can also be measured to check the efficacy of treatment.

13 Myasthenia gravis Myelin sheath Axon Nico(nic receptor Muscle Acetylcholine Autoan(bodies against the nico(nic receptors Contrac(on Muscle weakness Blocking of transmission

14 Autoimmune thyroid diseases Hashimoto s thyroidi(s: Graves-Basedow disease: B CD4 T CD8 T CD4 T TSHR-reac(ve B cell B An(-TPO, An(-thyroglobulin ADCC, lysis Autoreac(ve Plasma cell Autoreac(ve CTL Thyreocyte TSHR An(-TSH receptor an(body Pathological s(mula(on Lysis/apoptosis Apoptosis Hypothyroidism (T3/T4, TSH ) Hyperthyroidism (T3/T4, TSH )

15 Autoan*bodies in systemic diseases Examples: An(-nuclear an(bodies (ANA) An*-citrullinated protein an*bodies (ACPA) An(-neutrophil cytoplasmic an(bodies (ANCA) Rheumatoid factor (RF, an*-igg an*bodies, usually of IgM isotype but can be IgG or IgA) An*phospholipid autoan*bodies (pl. an*-cardiolipin, an*-β2 glycoprotein I) Detec*on of such autoan*bodies can be diagnos(c and also have prognos(c significance. Their levels can also be measured to check the efficacy of treatment. IgG RF IgG IgG IgG RF IgG Rheumatoid factor of IgM isotype Rheumatoid factor of IgA isotype

16 An*-nuclear an*bodies (ANA) They recognize different nuclear structures, such as: An(-double-stranded DNA an(bodies (an*-dsdna) Mainly in SLE An*-Smith (an*-sm), against ribonucleoproteins SLE An(-Scl-70, against topoisomerase I Scleroderma An(-centromere an*bodies Scleroderma, primary biliary cirrhosis An*-Ro (an*-ssa) and an*-la (an*-ssb) Sjögren s syndrome, SLE An(-Jo-1 against his*dyl-trna synthetase Polymyosi(s, dermatomyosi(s An*-histone an*bodies Drug-induced SLE

17 Lupus nephri*s Apopto(c material Released chroma(n and histone proteins Deposi(on of apopto(c material in the glomerular basal membrane APC Th B An(-dsDNA Circula(ng + locally formed immunocomplexes Immunocomplex-mediated glomerulonephri(s (Type III. hypersensi(vity)

18 An*-neutrophil cytoplasmic an*bodies (ANCA) Have two main types: Perinuclear paxern (p-anca) Cytoplasmic paxern (c-anca) Indirect immunofluorescence microscopy An*gen: mainly myeloperoxidase (MPO) Examples: Ulcera*ve coli*s Churg-Strauss syndrome Microscopic polyangii*s Primary sclerosing cholangi*s An*gen: mainly proteinase 3 (PR3) Examples: Wegener s granulomatosis (GPA: Granulomatosis with polyangi*s)

19 Detec*on of autoan*bodies Screening: Direct immunofluorescence: Performed on *ssue samples taken from the pa*ent. (e.g. dermatological or nephrological diseases, see in the clinical phase) Indirect immunofluorescence: The pa*ent s serum is tested in different cell cultures or *ssue types for autoan*bodies. Different autoan*bodies produce specific paxerns with certain *ssues or cells (e.g. homogenous nuclear, nucleolar, centromeric, mitochondrial, cytoplasma*c, etc.) An(gen-specific serological methods: Done to confirm the diagnosis ader a posi*ve screening test or ader the evalua*on of the clinical signs and symptoms of the disease. Methods: ELISA Western blot Radial immunodiffusion 6-8th prac*ces

20 Characteris*cs of tests Immunofluorescence: not specific, shows paxerns, mul*plex image, manual, many autoan*bodies cannot be detected What is this? ELISA: an*gen-specific, can measure individual autoan*bodies, can be automated, can iden*fy new autoan*gens Time? Mul(plex microarray technology: an*gen-specific, complex autoan*body paxerns, can be automated Quick and specific

21 Immunofluorescence I. Direct immunofluorescence test from the renal manifesta*on of SLE (lupus nephri*s): Membranous glomerulonephri*s (see from pathology and nephrology) 1. Biopsy from the kidney of the pa*ent 2. Glomerulus with PAS reac*on: thickened basal membrane 3. Direct IF microscopic image of a glomerulus: Deposi*on of IgG immunocomplexes in the GBM (Type III. hypersensi*vity)

22 Immunofluorescence II. An*-TPO autoan*bodies in a thyroid *ssue sec*on Mitochondrial staining paxern in a kidney *ssue Nucleolar paxern in Hep2 cells (an*-ssa) Homogenous nuclear staining in Hep2 cells (an*-dsdna)

23 Immunofluorescence III. Detec*on of An(-dsDNA from the serum of the pa*ent with indirect immunofluorescence microscopy in different cell types: HEp cell culture (human epithelial tumor) Crithidia luciliae cells (pro*st parasite) Rat liver *ssue

24 ANAscreen - microplate ELISA The ELISA plate is sensi*zed with a mixture of an(gens derived from the nuclei of Hep2 cells: dsdna histone centromere SSA/Ro, SSB/La Sm, Sm/RNP Scl-70, Jo-1 ANAscreen If posi(ve, than the test is repeated with ELISA plates each sensi(zed with only one specific an(gen. an(-dsdna an(-histone an(-cenpb an(-ssa an(-ssb an(-scl-70 an(-jo-1 an(-sm an(-rnp

25 References (not in order) Poletaev AB 1, et al.: Immunophysiology versus immunopathology: Natural autoimmunity in human health and disease. Pathophysiology Jun;19(3): doi: /j.pathophys Epub 2012 Aug 9. Nguyen TT 1, Elsner RA 2, Baumgarth N 3 : Natural IgM prevents autoimmunity by enforcing B cell central tolerance induc(on. J Immunol Feb 15;194(4): doi: /jimmunol Epub 2015 Jan 16. Binder CJ 1 : Naturally occurring IgM an(bodies to oxida(on-specific epitopes. Adv Exp Med Biol. 2012;750:2-13. doi: / _1. Lutz HU 1 : Homeosta(c roles of naturally occurring an(bodies: an overview. J Autoimmun Dec;29(4): Epub 2007 Sep 12. Lutz HU 1, Binder CJ, Kaveri S: Naturally occurring auto-an(bodies in homeostasis and disease. Trends Immunol Jan;30(1): doi: /j.it Epub 2008 Dec 4. Aziz M 1, et al.: The role of B-1 cells in inflamma(on. Immunol Res Dec;63(1-3): doi: / s Savage HP 1,2, Baumgarth N 1,2,3 : Characteris(cs of natural an(body-secre(ng cells. Ann N Y Acad Sci Jun 23. doi: /nyas Grönwall C 1, Vas J, Silverman GJ: Protec(ve Roles of Natural IgM An(bodies. Front Immunol Apr 4;3:66. doi: /fimmu ecollec*on Elkon K 1, Casali P: Nature and func(ons of autoan(bodies. Nat Clin Pract Rheumatol Sep;4(9): doi: /ncprheum0895. Grönwall C 1, Silverman GJ: Natural IgM: beneficial autoan(bodies for the control of inflammatory and autoimmune disease. J Clin Immunol Jul;34 Suppl 1:S doi: /s Epub 2014 Apr 2. Cohen IR 1 : Biomarkers, self-an(gens and the immunological homunculus. J Autoimmun Dec;29(4): Epub 2007 Sep 20.

26 References Vas J 1, Grönwall C, Silverman GJ: Fundamental roles of the innate-like repertoire of natural an(bodies in immune homeostasis. Front Immunol Feb 5;4:4. doi: /fimmu ecollec*on Xu X 1, et al.: Human-derived natural an(bodies: biomarkers and poten(al therapeu(cs. Future Neurol. 2015;10(1): Casali P 1, Schewno EW: Structure and func(on of natural an(bodies. Curr Top Microbiol Immunol. 1996;210: Panda S 1, Ding JL 2 : Natural an(bodies bridge innate and adap(ve immunity. J Immunol Jan 1;194(1): doi: /jimmunol Mannoor K 1, Xu Y, Chen C: Natural autoan(bodies and associated B cells in immunity and autoimmunity. Autoimmunity Mar;46(2): doi: / Epub 2013 Jan 10. Madi A 1, et al.: The natural autoan(body repertoire in newborns and adults: a current overview. Adv Exp Med Biol. 2012;750: doi: / _15. Kaveri SV 1 : Intravenous immunoglobulin: exploi(ng the poten(al of natural an(bodies. Autoimmun Rev Sep;11(11): doi: /j.autrev Epub 2012 Feb 12. Choi YS 1, et al.: B-1 cells in the bone marrow are a significant source of natural IgM. Eur J Immunol Jan; 42(1): doi: /eji Epub 2011 Nov 28. Rahyab AS 1, et al.: Natural an(body - Biochemistry and func(ons. Glob J Biochem. 2011;2(4): Baumgarth N 1 : The double life of a B-1 cell: self-reac(vity selects for protec(ve effector func(ons. Nat Rev Immunol Jan;11(1): doi: /nri2901. Epub 2010 Dec 10. Chan AY 1,2, Anderson MS 1 : Central tolerance to self revealed by the autoimmune regulator. Ann N Y Acad Sci Nov;1356:80-9. doi: /nyas

27 References Anaya JM 1 : The diagnosis and clinical significance of polyautoimmunity. Autoimmun Rev Apr-May; 13(4-5): doi: /j.autrev Epub 2014 Jan 11. Pisetsky DS 1 : An(-DNA an(bodies - quintessen(al biomarkers of SLE. Nat Rev Rheumatol Nov 19. doi: /nrrheum Czömpöly T 1, et al.: An(-topoisomerase I autoan(bodies in systemic sclerosis. Autoimmun Rev Jul;8(8): doi: /j.autrev Epub 2009 Feb 13. Nihtyanova SI 1, Denton CP: Autoan(bodies as predic(ve tools in systemic sclerosis. Nat Rev Rheumatol Feb;6(2): doi: /nrrheum Liberal R 1, et al.: Diagnos(c and clinical significance of an(-centromere an(bodies in primary biliary cirrhosis. Clin Res Hepatol Gastroenterol Dec;37(6): doi: /j.clinre Epub 2013 Jul 19. Zampieri S 1, et al.: An(-Jo-1 an(bodies. Autoimmunity Feb;38(1):73-8. Aggarwal A 1 : Role of autoan(body tes(ng. Best Pract Res Clin Rheumatol Dec;28(6): doi: / j.berh Epub 2015 May 23. Csernok E 1, Moosig F 1 : Current and emerging techniques for ANCA detec(on in vasculi(s. Nat Rev Rheumatol Aug;10(8): doi: /nrrheum Epub 2014 Jun 3. Poletaev AB 1, Stepanyuk VL, Gershwin ME: Integra(ng immunity: the immunculus and self-reac(vity. J Autoimmun Feb-Mar;30(1-2): doi: /j.jaut Poletaev AB 1 : The immunological homunculus (immunculus) in normal state and pathology. Biochemistry (Mosc) May;67(5):600-8.