1. Autoimmunity and imunopathology
Tomas Milota, MD.
Department of Immunology,
Department of Rheumatology,
Second Medical Faculty, Charles University
and Motol University Hospital, Prague

2. Basic characteristics of immunity
Key system for homeostasis maintenance:
Protection against pathogens (PAMPs)
Autotolerance
Immune surveillance – removal of damaged or mutated cells
+ broad spectrum of non-immunological functions
■ interactions with central nervous system
■ interactions with endocrine system
Immunodeficiency
Autoimmunity
Malignancy

3. Characteristics of basic immune system disorders
Allergy – process, when immune system in predisposed individuals exerts inflammatory response against exogenous antigens – allergens (which is tolerated in healthy individuals) upon repeated expositions
Immunodeficiency – condition, when one or more components of immune system is completely missing or is partly defective, it is usually manifested with recurrent infections and/or immune system dysregulation
Autoimmunity – process, when immune system recognizes own structures (cells and tissues) as foreign and causes their destruction by cytotoxic mechanisms

4. Immunedeficiency vs. Autoimmunity
Monogenic causes of autoimmunity (rare)
ADA2 deficiency:
Monogenic vasculitis
AIRE deficiency:
APECED syndrome
FoxP3 deficiency:
IPEX syndrome
NOD2 GOF mutation:
Blau syndrome
PID with high prevalence of autoimmune complications:
• selective IgA deficiency
• CVID
• CMC
• CID
• AR- HIES
IL-10 deficiency:
Crohn disease
C3 deficiency:
SLE-like
Polygenic and multifactorial ethiology (common concept)

5. Exogenous factors Endogenous factors
■ Infectiosn (EBV – RS, H.py – CAG)
■ UV radiation (SLE)
■ Drugs (prokainamid,
hydrakazin – SLE, statiny –
dermato/polymyositis)
■ Smoking (vasculitis –
Burger disease,
rheumatoid arthritis)
■ Stress, trauma, chemicals
■ Genetic predisposition
■ Gender
■ Age
Mosaic of autoimmunity

6. Genetic predisposition
Monogenic causes autoimmune diseases
■ APECED (Autoimmune PolyEndocrinopathy, Candidosis, Ectodermal Dysplasia) – mutation AIRE gene (AutoImmune REgulator) – AR heredity
■ IPEX (autoimmune polyendocrinopathy, enteropathy) – mutation FOXP3 (TREGs) – X linked
■ CTLA4 deficiency – mutation in CTLA4 (inhibitory molecule) – AD heredity
■ ALPS (Autoimmune Lymphoproliferative Syndrome) – mutation in FAS (AD), FAS-L, CASP10 (AD/AR)

7. Kaleidoscope of autoimmunity
2) HLA asociace
2) MHC I association (in polygenic/multifactorial)
■ HLA B27 – spondylarthritis
■ HLA B51 – Behcet disease
2) MHC II association (in polygenic/multifactorial)
■ HLA DQ2, HLA DQ8 – Celiac disease
■ HLA DR3, HLA DR4 – Hashimoto thyreoiditis
■ HLA DR3, HLA DR4, HLA DQ2, HLA DQ8 – Type 1 diabetes
■ HLA DR15 – roztroušená skleróza
Protective variants:
HLA DR7 - Hashimoto hyreoiditis
HLA DR14 – Multiplex sclerosis
HLA DR14, HLA DR15 - Type 1 diabetes
Kaleidoscope of autoimmunity
High prevalence of Hashimoto hyreoiditis a Celiac disease in Type 1 diabetes patients

8. 2) Gene polymorphisms for cytokines and their receptors
Cytokinová rodina
Asociované onemocnění
Rodina IL-2
T1DM, RA, IBD, MS, vitiligo
Rodina IL-12
AS, IBD, PsA/Ps
Rodina IL-23
AS, Ps/PsA, IBD
Rodina IL-10
IBD, T1D
IFN I
SLE, SS

9. Th1 Th2 Thf Th17 Treg APC IFN-I IL-12 IL-4 IL-6, ICOS
T-bet / STAT4
IFN-I
CXCR3
IFN gamma
IL-12
Th2
GATA-3 / STAT6
IL-4
CRTH2
IL-4, 5, 13
CD80,CD86 / CD28
CD40 / CD40L
OX40 L / OX40
ICOS-L / ICOS
PD-1L / PD-1
PD-2L / PD-2
Thf
IL-6, ICOS
Bcl-6
APC
CXCR5
IL-21
TGF-beta, IL-6, IL-23
Th17
Ror-g / STAT3
CTLA4 /
IL-10 /
TGF beta
CCR6
TGF-beta
IL-17
Treg
FOXP3 / STAT5
IL-10, TGF beta

10. Phases of autoimmunity development
Genetic
predisposition:
● Familial occurrence
● MHC
● (gender, age)
Environment
● Infection
● UV radiation
● Smoking
● Drugs
Immune systém dysregulation:
● dysbalance stimulatory / inhibitory signals
● impaired cytokine production
SUSCEPTIBILITY
INITIATION:
Autoantibody detection
PROPAGATION:
Unspecific manifestation (sub/febrilie, fatigue)
MANIFESTATION:
Clinically specific symptoms

11. Epidemiology I: gender influence
Disease
Incidence
Rheumatoid arthritis
10 – 50 :
JIA
1 – 20 :
Ankylosing spondylitis
6 – 7 :
Sjogren syndrome
7 :
SLE
1 – 8 :
Systemic scleroderma
0,3 – 2 :
Myositis
0,1 : 6M
16R
35R
50R
JIA
SLE RA
GCA

12. Epidemiology II: age influence
Disease
M:F Ratio
SLE
10 – 20x in F
Sjogren syndrome
Up to 9x in F
Systemic scleroderma
3 – 8x in F
Myositis
Up to 3x in F
JIA
3 – 4x in F
Rheumatoid arthritis
2 – 3x in F
Ankylosing spondylitis
2 – 3x in M
Estrogenys increase expression of IFN I a IRF 5 (interferon regulating faktor 5)
Overexpression of X linked genes: CD40L, CXCR3, OGT, FOXP3, TLR7, TLR8, IL2RG, BTK, and IL9R
Different changes in cell phenotype of males and females during aging
Differences microbiome composition between males and females

13. Classification of autoimmune diseases
1) According to pathophysiological mechanism: Coombse and Gell Classification
Type
Mechanism
Disease I.
IgE mediated
IgE
EGPA (Churg – Strauss)
II.
ADCC (Antibody Dependent Cell Cytotoxicity)
IgG, IgM
AIHA, ITP
Myasthenia gr.
Gravesova thyreoiditis
III.
Imunocomplex reactions
IgG
complement
SLE
Reactive arthritis
IC glomerulonephritis
IV.
Delayed hypersensitivity
T lymphocytes
T1DM
Hashimoto thyreoiditis
Multiplex sclerosis

14. 2) According to localisation
Organ specific:
Tissue specific autoantibodies may be detected
Autonatibodies may be diagnostic or pathogenic (activating / inhibiting / cytotoxic)
■ ENDOCRINOPATHY: Graves thyreoiditis (TRAK), Hashimoto thyreoiditis (anti TG, anti TPO), T1DM (anti GAD, anti IAA, anti IA2)
■ AI CYTOPENIAS: AIHA (anti erythrocyte AAb – direct/indirect Coombs test), ITP
(anti thrombocytic AAb), AI neutropenia (anti leukocytic)
■ NEUROLOGIC DISEASES: Myasthenia gravis (anti AceCh-R), Multiplex sclerosis
(no specific AAb present)
■ DERMATOLOGIC DISEASES: pemphigus (anti desmoglein 1,3), psoriasis (no specific AAb present)

15. B) Organ localized:
Organ Unspecific AAb present
Organ specific disease
■ Ulcerative colitis (ANCA)
■ Crohn disease (ASCA)
■ AI hepatitis (type I, II, III: ASMA/F-aktin, LKM, SLA, + ANA, anti dsDNA)
+ possible association with HCV infection in type II
■ Celiac disease (anti EMA, anti TRG)
■ Primary billiary cirrhosis (AMA)

16. C) Systemic autoimmune diseases
Presence of UNspecific AAb (ANA, ENA, RF, ACPA)
Multiorgan manifestation
■ systemic connective tissue diseases (SLE, dermato/polymyositis, Sjogren syndrome, systemic scleroderma)
■ systemic vasculitis (EGPA, GPA, MPA, PAN, OBA, Kawasaki,, Takayasu, ……)
■ rheumatic diseases (Rheumatoid arthritis, JIA, spondylarthritis)

17. Therapy
■ Non – steroid antiflogistics
■ Glucocorticosteroids
■ Disease Modifying Antirheumatic Drugs (DMARDs)

18. NSA Mechanisms of action:
Inhibition of cyclooxygenase (COX-1 – constitutive, COX-2 inducible): unselective (ASA, ibuprofenum, diclofenacum, ketoprofenum, indometacinum), COX-2 preferential (meloxicam, nimesulid), COX-2 selective (celekoxib, etorikoxib, rofekoxib)
Clinical effect:
Reduce production of proinflammatory cytokines – prostaglandines: analgetic, antipyretic a antiedematic effect, functional improvent of the joints
Administration: systemic vs. local
Adverse events:
Gastrointestinal toxicity (peptic ulcer disease)
Renal toxicity (renal insificiency, tubul-interstitial nephritis, papilar necrosis)
Hepatal toxicity
Dermatological toxicity (urtcaria)
Platelets disorders (thrombocytopenia)
Respiratory toxicity (nasal polyposis, ASA induced asthma)

19. Glucocorticoids Mechanisms of action:
- binding GRE (glucocorticoid response elements):
- non-genomic effect (immediate): COX-2 inhibition, reduction of proinflammatory cytokine release
genomic (delayed effect):
Effect on activity of transcriptional factors (NFkB, AP-1)
Clinical effect:
Reduction of proinflammatory cytokines, leukocytes activity, analgetic, antipyretic and antiedematic effect, functional improvent of the joints + disease modifying effect!!!

20. Administration:
■ systemic (parenteral, peroral) vs. local (intraarticular)
■ pulse therapy (500 – 1000mg Solu-medrol) – high dose (40 – 60 mg Prednisone) – medium dose (20 mg Prednison) – low dose (5 – 10mg Prednisone)
Adverse events
Infections (secondary immunodeficiency)
Higher risk of peptic ulcer disease
Osteoporis (densitometric screening necessary!!!)
Atherosclerosis
Impaired glucose metabolism
Negative impact on CNS (insomnia, emotional lability, psychosis)
Adrenocortical insuficiency
Ostatní: eye cataract, hirsutism, aseptic osteonecrosis, cushingoid habitus, glaukoma, sekundary amenorhea,…..

21. Disease modifying drugs (DMARDs) ■ Conventional synthetic (csDMARDs)
- methotrexate, leflunomide, antimalarics, ciclosporine,…
■ Biologic (bDMARDs)
- anti TNF alpha (infliximab, etanercept, adalimumab,……), anti IL-17 (ixekizumab, sekukinumab,…..), anti IL-1(anakinra, canakinumab,….) apod.
■ Targeted synthetic (tsDMARDs):
- tofacitinib (JAK-1, JAK-3 inhibitor), baricitinib (JAK-1, JAK-2 inhibitor)

22. Conventional synthetic (csDMARDs):
Mechanism of action
Antiproliferative: methotrexate, leflunomide, azathioprine, cyclophosphamide)
Inhibition of Ca dependent signalization (cytokines resposnible to activation and proliferation: Cyclosporin A
Inhibition of endosome: antimalarics
Unknown mechanism: sulfasalazin
Adverse event:
- hepatotoxicity, myelotoxicity, nephrotoxicity, GIT toxicity, retinopathy (Plaquenil), pneumonitis (methotrexate), cystitis (cyclophosphamide)
Remedy
Dosage regimen
Hydroxychloroquine
200 (400) mg dayly
Sulfasalazine
500 – 2000 (3000) mg dayly
Methotrexate
5 – 20 (25) mg weekly + Ac. folicum
Leflunomide
10 – 20mg daly
Cyclosporin A
2,5 – 3,2mg/kg/day
Azathioprine
1 – 3mg/kg/day

23. Biologické (bDMARDs)
monoclonal antibody: Chimeric (infliximab), humanized (certolizumab) or human (adalimumab, sekukinumab)
or fuze proteins (etanercept, abatacept)
block proinflamatoy cytokine or its receptor (anakinra), costimulatory molecules (abatacept)
Target
Remedy
Anti IL-1R
anakinra
Anti IL-1beta
canakinumab
Anti TNF alpha
infliximab, etanercept, adalimumab, certolizumab, golilumab
Anti IL-6RA
tocilizumab, sarilumab
Anti IL- 17A
sekucinumab, ixekizumab
CTLA4
abatacept
Anti BAFF
belilumab
Adverse events (Anti TNF alpha):
Hiher risk of infections (TBC, hepatitida B)
Autoimmmune complications (vaskulitiy, iSLE, sarkoidosis, demyelinizing disorder of CNS and PNS)
Panyctopenia, hepatal damage

24. Th1 Th2 Thf Th17 Treg APC IL-1 IFN-I IL-12 TNF-α IL-4 IL-6, ICOS
T-bet / STAT4
IL-1
IFN-I
CXCR3
Anakinra Canakinumab
IFN gamma
IL-12
TNF-α
Ustekinumab (+IL-23)
Th2
GATA-3 / STAT6
Etanercept
Adalimumab
Cetolizumab
Golilumab
IL-4
CRTH2
IL-4, 5, 13
Tocilizumab
CD80,CD86 / CD28
CD40 / CD40L
OX40 L / OX40
ICOS-L / ICOS
PD-1L / PD-1
PD-2L / PD-2
Thf
IL-6, ICOS
Bcl-6
APC
CXCR5
IL-21
TGF-beta, IL-6, IL-23
Th17
Ror-g / STAT3
Ustekinumab (+IL-12) Risankizumab
Abatacept
CTLA4 /
IL-10 /
TGF beta
CCR6
Sekucinumab
Bimekizumab
Ixekizumab
IL-17
TGF-beta
Treg
FOXP3 / STAT5
IL-10, TGF beta

25. Thank you for attention!