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The 1rst Kuwait-North American Update in Internal Medicine Conference 8-9 February 2014. BIOMARKERS TO GUIDE TREATMENT IN RA. Henri A. Ménard, MD, FRCP (C) Professor of Medicine McGill University McGill University Health Center. Rheumatoid Arthritis (circa 1987).
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The 1rst Kuwait-North American Update in Internal Medicine Conference 8-9 February 2014 BIOMARKERS TO GUIDE TREATMENT IN RA Henri A. Ménard, MD, FRCP (C) Professor of Medicine McGill University McGill University Health Center
Rheumatoid Arthritis (circa 1987) Chronic progressively deforming polyarthritis Extra-articular involvement (lung fibrosis, serositis, scleritis, nodules, vasculitis, sicca) X-Ray joint damage in the 1st year in 30-50% of patients. Permanent inability to work within 5 yrs in 40%. Life expectancy shortened by 3-14 yrsdepending on the severity of the disease Textbook
RA Biomarkers • Clinical 2010 • AutoAbs 2010 • Genetic • Imaging Early Intervention Prognosis RA TEXTBOOK љњҗ EA/ERA Office
The ACR-EULAR 2010 Classification Criteria A probabilistic approach to early diagnosis CLINICAL PROGRES
1987 CRITERIAMean Disease Duration: 8 Years Arthritis and Rheumatism 31:315-24,1988
Goals 2010 In patients with undifferentiated arthritis : • Identify those at high risk of chronicity and erosive damage • candidates for DMARD therapy • Not exclude patients later in the disease course
2010 ACR/EULAR RA CRITERIA • Target population 1) at least 1 joint with definite clinical synovitis (swelling)* • 2) the synovitis is not better explained by another disease† • Classification: add score of categories A–D (6/10 is needed for a definite RA)‡ • A. Joint involvement§Score • 1 large joint 0 • 2-10 large joints 1 • 1-3 small joints (with or without involvement of large joints)# 2 • 4-10 small joints (with or without involvement of large joints) 3 • >10 joints (at least 1 small joint)** 5 • B. Serology (at least 1 test result is needed for classification)†† • Negative RF and negative ACPA 0 • Low-positive RF or low-positive ACPA 2 • High-positive RF or high-positive ACPA 3 • C. Acute-phase reactants (at least 1 test result is needed for classification)‡‡ • Normal CRP and normal ESR 0 • Abnormal CRP or abnormal ESR 1 • D. Duration of symptoms§§ < 6 weeks 0 • > 6 weeks 1
HYPOTHETICAL COURSE of RA 1987 Established RA 2010 Early RA Inflammation clinical threshold Pre-RA Auto-Ab Time
POST-2010 PERSPECTIVES Extrapolation Validation Stratification No erosions New treatment approaches New remission criteria Aggressive Tx for less active disease Societal cost of early Tx with biologicals Need for local reference values for APR and Auto-Abs.
EXPERT PANEL 12 12 KUWAIT
Biomarkers For Early Disease Clinical : ACR-EULAR 2010 Criteria Serological : Citrullinated Immune Systems
Studying Auto-Immune Systems • DIAGNOSIS Auto-Abs Clinician • PROGNOSIS • MONITORING • TOOLS FOR BIOLOGY Auto-Ags Biologist • PHYSIOPATHOLOGY • CLUES TO ETIOLOGY Roadmap to Personalized Medicine
Anti-IgGs (RFs) Agn (Many) Abn (Many) Rheumatoid Arthritis An In Vivo ELISA Secondary Systems Amplification Primary Systems Specificity
RA-Associated Auto-Immune Systems Nucleus: DNP/ssDNA/histones/macro-histone, LMG and HMG proteins, Ro (SS-A), hnRNP(s) A2/B1, etc… Cytoplasm: intermediary filaments (vimentin, filaggrin, reticulin, fodrin), endoplasmic reticulum, chaperone(s), cytokeratin(s), etc… Extracellular Matrix Proteins: collagen(s), GAGs, link protein(s), elastin, fibulin, keratin, etc… Enzymes and Inhibitors: G6PI, PDI, calpastatin(s), follistatin-related protein,hyaluran synthase, enolase, aldolase, PADI4, MPO, etc… Others: lactoferin, phospholipids, advance glycation endproducts (AGE), etc… Rheumatoid Factors: poly-, oligo-, monoclonal Ig isotypes targeting Fc, Fab, idiotopes, paratopes, etc….
RA-Specific Immune Systems A C P A s • Anti-Citrullinated PEPTIDE Antibodies. • Anti-Citrullinated PROTEINS Antibodies
Citrullination isthe Enzymatic Conversion ofArginine To Citrulline The Antigen(s)
CitrullinationAn Intracellular Agonic Event • PADIs are present in most cells: epithelial, fibroblast, osteoblast, endothelial, myeloid and dentritic cells but NOT IN LYMPHOID CELLS. • Citrullination occurs during the calcium influx of early apoptosis. Vimentin is the first protein to be citrullinated in macrophages (Senshu). Cit-Vimentin = the Sa antigen. • Citrullination is thus a cellular agonic event, a NORMAL feature of inflammation and repair.
Citrullination Is AlsoA Secondary Extracellular Event Fibrin, Collagen, ANY PROTEIN Exocytosis / Apoptosis No known natural inhibitor
Five Points To Remember About Cit-Proteins/ACPAs In Joints • Cit-proteins are found in all inflammed tissues and fluids, not CCP. • The PANNUS CITRULLINOME is mostly made of the Sa Ag (Ménard 1988) i.e. neo-Ags on Cit-VIMENTIN (Ménard 2004, Bang 2007, Tilleman 2008) generated during apoptosis and present in ACPA-containing immune complexes (Van Steendam 2008). • The SYNOVIAL FLUID CITRULLINOME is mostly made of cit-FIBRIN (Serre 2006, Pruijn 2006) generated extracellularly and present in ACPA-containing immune complexes (Zhao 2008). • The pannus is an ectopic lymphoid tissue producing RF, anti-AgN including ACPAs (Smiley 1970, Serre 2000). • ACPAs are IgGs typical of a mature/ongoing polyclonal Ag-driven response (Ménard 1984, Schellekens 1998 and Ioan-Facsinay 2008, 10) .
Anti-CCP2 ELISA : Designed For Screening Populations Ceiling effect ULT O.D. ULN Low Threshold Anti-CCP2 Titer van Venrooij W 2003
Retrospective Study Scandinavian Blood Donors SRDahlqvist et al. A&R 2003
Hypothetical Course of RA 1987 Established RA 2010 Early RA Inflammation clinical threshold Pre-RA Auto-Ab Time
Prospective StudyNorth American Natives • highest rates of RA in the world (2-4%) • high rates of multicase families • predisposing HLA-DRB1 alleles very common • high levels of antibodies (RF, ACPA) Ideal population to identify individuals at risk…
Co-PI : HA Ménard Montreal, Quebec PI : H El-Gabalawy, Winnipeg, Manitoba
Anti-Sa ELISA (2004) : Design For Prognosis and Monitoring Individual RA Patients ULT ULT O.D. ULN ULN Anti-CCP Titer Anti-Sa titer
Anti-Sa / anti-CCP2In NANA Prospective Study Anti-CCP2 ELISA 79% 20% 9% RA FDR UNRELATED 51% 0% 0% Anti-Sa ELISA Ioan-Facsinay A et al. (El Gabalawy H, Ménard H) A&R 2008
Baseline AutoAbs And Erosions After 3 years Prospective Early RA Sherbrooke Cohort Titers at Inclusion (n) Erosive (≥ 5) % (n) Very Erosive (≥14) % (n) RF (n=253) Neg (140) Pos (113) Low (21) Moderate/High (92) 42.9 (60) 55.8 (63) 42.9 (9) 58.7 (54) p<0.05 29.3 (41) 40.7 (46) 38.1 (8) 32.6 (38) Anti-CCP2 (n=253) Neg (156) Pos (97) Low (11) Moderate/High (86) 42.9 (67) 57.7 (56) 54.5 (6) 58.1 (50) p<0.05 31.4 (49) 39.2 (38) 36,4 (4) 39.5 (34) Anti-Sa (n=253) Neg (195) Pos (58) Low (18) Moderate/High (40) 41.0 (80) 74.1 (43) p<0.0001 66.7 (12) 77.5 (31) p<0.0001 29.2 (57) 51.7 (30) p<0.005 33.3 (6) 60.0 (24) p<0.0005 Guzian C et al. (Boire G, Ménard H) AR&T 2010
Examples of Anti-CCP2 in Non-Rheumatoid Patients • Idiopathic inflammatory myopathy (Rheumatology (Oxford) 2009) from a Tertiary Care Center in Barcelona. 13% positive anti-CCP (75% mod-high titers). No arthritis, no AKA. • 25% positive anti-CCP in SLE from low to high titers. (Unpublished Ménard and Van Venroij). No arthritis, no anti-Sa. • Chronic infections like HIV (South Africa), Tb (India) No arthritis. Anti-CCP positive, anti-Sa status unknown, • RA-like conditions: HVB or HVC with cryo, CPPD with hemochromatosis, Psoriatic Arthritis, IBD Arthritis. Some anti-CCP pos but anti-Sa always negative.
ERA NHL-RA RA VASC RTX RTX SR CSR ERA RA VASC Palindrome CSR MonoA RA CSR CR CR MONITORING RA WITH ANTI-Sa CSR = Clinical Serological Remission Anti-CCP2 never changed significantly Rotman J (Ménard HA) European Workshop Rheum Res Toulouse 2008
Summary Of ACPA in Pre-RA • Anti-CCP and RF are present up to 15 years before disease onset; • The higher the anti-CCP titres the shorter the time to disease onset (retrospective data). • Anti-Sa Abs define a sub-group of RA patients with higher titres of anti-CCP and higher Ig isotype usage = MORE SEVERE • Anti-Sa Abs are strictly RA disease-associated, not anti-CCP.
SPECIFICITY (85-100%) anti-Sa >> CCP > MCV SENSITIVITY 40% to 80% depending on test and patients i.e. phase of disease, age at onset, treatment. anti-CCP = MCV > anti-Sa For SCREENING anti-CCP > MCV >> Sa more sensitive, less specific. for DIAGNOSIS anti-Sa>> CCP > MCV for MONITORING anti-Sa >> MCV >> CCP = 0 ACPA are highly correlated with RF 80-90% ACPA also have RF 50-85% RF also have ACPA 25-30% RF(-) have ACPA Same in children with adult form Clinical Summary of ACPA LiteratureIn Early and Established RA
Interpretation Of The Clinical Data NEPHRITIS ARTHRITIS SLE RA ANA Anti-dsDNA Anti-CCP Anti-Sa “It is not one or the other, it is one and the other”. Ménard HA. Nature Clin Practice Rheumatol 2007.
SHUKRAN ALA ALDAWAH