Systemic Lupus Erythematosus Epidemiology of SLE • Prevalence - 1/2,000 people • Sex - 10:1 female predominance • Age at onset 16-55 years: 65% (F:M = 10:1) <16 years: 20% (F:M = 3:1) >55 years: 15% (F:M = 7:1) • Race - more common in Blacks, Hispanics, and Asians than in Whites Common Manifestations of SLE Constitutional Symptoms • Fatigue • Fever • Weight loss Mucocutaneous Involvement • Photosensitive rash • Oral ulcers • Alopecia Arthralgias/Arthritis Manifestations of SLE (con’d) Kidneys - Glomerulonephritis Central Nervous System - Headache, seizures, stroke Peripheral Nervous System - sensory or motor Lungs - pleuritis, pneumonitis, hemorrhage Heart - pericarditis, myocardial infarction, valve disease GI - serositis, mesenteric vasculitis, pancreatitis Hematopoietic - lymphadenopathy, autoimmune cytopenias, antiphospholipid antibody syndrome Target Antigens in SLE • Nuclear antigens (e.g., dsDNA) • Cytoplasmic antigens (e.g., ribosomal proteins) • Cell surface antigens (e.g., blood cells) • Soluble antigens in sera (e.g., IgG, phospholipids) Anti-dsDNA Antibodies Evidence for a Pathogenic Role • Presence correlates with renal involvement • Serum levels correlate with disease activity • Concentration is enriched in glomerular eluates • Some monoclonal anti-dsDNA can produce lupus nephritis Anti-DNA Mediated Renal Injury Proposed Mechanisms • Deposition of circulating immune complexes • Binding of DNA to GBM (e.g., based on charge) • Binding of anti-dsDNA to glomerular antigens (e.g., due to polyspecificity - heparin sulfate, laminin) Autoantibodies in CNS Lupus (DeGiorgio et al.: Nature Med 7:1189,2001) 1) Some anti-DNA antibodies bind receptors for glutamate. 2) Glutamate receptors contribute to learning and memory. 3) Overstimulation of glutamate receptors can cause excitotoxic neuron death. Autoantibodies in CNS Lupus (DeGiorgio et al.: Nature Med 7:1189,2001) (continued) 4) Anti-DNA antibodies mediate neuronal cell death. 5) CSF from a patient with CNS lupus contain anti-DNA antibodies that mediate neuronal death. Antiphospholipid Antibodies aPL antibodies bind complexes of phospholipids and plasma proteins: • Prothrombin-activator complex (activated factor X, factor V, prothrombin, calcium, phospholipid) • b2-glycoprotein I (a naturally occurring anticoagulant) Antiphospholipid Antibody Syndrome (APS) • Venous thrombosis • Arterial thrombosis • Recurrent fetal loss • Thrombocytopenia Prevention of Fetal Loss with Crry-Ig (Holers VM…Salmon JE: J Exp Med 195:211, 2002) Other Postulated Mechanisms • Defective clearance of apoptotic bodies (persistence of self nuclear antigens) • Failure of tolerance (T cells and/or B cells) • Activation of B cells and/or dendritic cells by self DNA or RNA through tolllike receptors (i.e., TLR-7 and TLR-9) Special Serologic Studies in SLE Antinuclear Antibodies (ANA) Anti-dsDNA Antibodies Anti-ENA Antibodies (RNP, Sm) Rheumatoid Factor (RF) Complement (C3, C4, CH50) ACR Criteria For SLE 1. Malar rash 2. Discoid Rash 3. Photosensitivity 4. Oral ulcers 5. Arthritis 6. Serositis 7. Renal disorder 8. Neurologic disorder 9. Hematologic disorder 10. Antinuclear antibody 11. Immunologic disorder Case History Patient: 33-year-old woman Symptoms: Fatigue, myalgias/arthralgias, pleuritic chest pain Signs: T-38.5oC Nodes - mild diffuse adenopathy Lungs - dullness at right base Joints - synovitis at the wrists and MCPs; small effusions in both knees Differential Diagnosis Infection • Virus (HIV, hepatitis, EBV, Coxsackie) • Gonococcus • Subacute bacterial endocarditis • Pneumonia • Tuberculosis Differential Diagnosis Infection • • • • • Virus (HIV, hepatitis, EBV, Coxsackie) Gonococcus Subacute bacterial endocarditis Pneumonia Tuberculosis Rheumatic Disease • Rheumatoid arthritis • Systemic lupus erythematosus Differential Diagnosis Infection • • • • • Virus (HIV, hepatitis, EBV, Coxsackie) Gonococcus Subacute bacterial endocarditis Pneumonia Tuberculosis Rheumatic Disease • • • • • Rheumatoid Arthritis Systemic lupus erythematosus Mixed connective tissue disease Polymyositis Polyarteritis nodosa Differential Diagnosis Infection • • • • • Virus (HIV, hepatitis, EBV, Coxsackie) Gonococcus Subacute bacterial endocarditis Pneumonia Tuberculosis Rheumatic Disease • • • • • Rheumatoid Arthritis Systemic lupus erythematosus Mixed connective tissue disease Polymyositis Polyarteritis nodosa Malignancy • Leukemia • Lymphoma Laboratory Data Hgb - 11.3 Hct - 34 WBC - 3,200 Platelets - 220,000 LFTs - wnl Creatinine - 1.0 Urinalysis - wnl EKG - wnl X-rays: Chest - small pleural effusion on the right Hands/knees - swelling, no bony abnormalities RF - 1:80 ANA - 1:160 Serology CH50 - low Anti-DNA - high Laboratory Data Hgb - 11.3 Hct - 34 WBC - 3,200 Platelets - 220,000 LFTs - wnl Creatinine - 1.0 Urinalysis - wnl EKG - wnl *X-rays: Chest - small pleural effusion on the right Hands/knees - swelling, erosions at MCP joints RF - 1:80 *ANA - negative Laboratory Data Hgb - 11.3 Hct - 34 WBC - 3,200 Platelets - 220,000 LFTs - wnl *Creatinine - 1.8 *Urinalysis - 2+ protein, RBCs EKG - wnl X-rays: Chest - small pleural effusion on the right Hands/knees - swelling, no bony abnormalities *RF - negative *ANA - 1:160 Laboratory Data Hgb - 11.3 Hct - 34 *WBC - 5,600 Platelets - 220,000 LFTs - wnl *Creatinine - 1.8 *Urinalysis - 2+ protein, RBCs EKG - wnl X-rays: Chest - small pleural effusion on the right Hands/knees - swelling, no bony abnormalities RF - 1:80 *ANA - negative Laboratory Data Hgb - 11.3 Hct - 34 *WBC - 84,000 Platelets - 220,000 LFTs - wnl Creatinine - 1.0 Urinalysis - wnl EKG - wnl X-rays: Chest - small pleural effusion on the right Hands/knees - swelling, no bony abnormalities *RF - negative *ANA - negative Principles of Management Careful monitoring Attention to psychosocial problems Topical therapy for skin involvement NSAIDs for arthritis/pleuritis Treat associated medical problems Steroids/cytotoxic drugs for refractory symptoms and/or life threatening manifestations Potential Biologically-Based Therapeutic Interventions for Lupus (a partial list) B Cell Targets • • • • • Anti-BLyS Anti-CD20 Anti-CD22 Anti-B7 TACI-Ig T Cell Targets • • • • Anti-CD3 Anti-CD4 Anti-CD40L CTLA4Ig Cytokine Targets • • • • Anti-IFN (a or g) Anti-TNF-a Anti-IL-10 Anti-IL-6R Complement System Targets • Anti-C5 • C3 convertase inhibitor (Crry-Ig) Regulatory Cell Targets • CD4+ CD25+ T Cells Stem Cell Transplantation Anti-BLyS (Belimumab) Summary BLISS-52 a Wallace BLISS-76 et al. Presented at the American College of Rheumatology Annual Meeting, Nov 9, 2010, Poster 1172. Changes in Serologic Measures -9.7% Anti-dsDNA Median % Change In Patients Positive at Baseline -43.3% -49.5% 51.9% C4 38.5% % Change Over Time In Patients With Low Baseline C4 16.7% # p <0.001, + p <0.01, * p <0.05 T Cell Costimulation Inhibition of T Cell Costimulation Systemic Lupus Erythematosus