Laboratory examinations in autoimmune disorders 三軍總醫院 內科部風濕免疫過敏科

與風濕病相關的自體抗體 SLE: ANA, Anti-dsDNA, Anti-Sm …… Drug-induced lupus: Anti-histone Rheumatoid arthritis: RF, ACPA (Anti- CCP) Mixed connective tissue disease (MCTD): Anti-RNP Polymyositis: Anti-Jo-1

與風濕病相關的自體抗體 Scleroderma : Anti-Scl-70, Anti-centromere Wegener’s granulomatosis: c-ANCA Microscopic polyangiitis p-ANCA Sjogren’s syndrome: Anti-Ro (SSA), Anti-La (SSB)  Antiphospholipid syndrome: Anti-cardiolipin, lupus anticoagulant, Anti-beta2-glycoprotein-I Ab

Frequency of antibodies in various autoimmune diseases ANA Anti-ds DNA Anti-Sm Anti-RNP Anti- SSA-Ro SSB-La Anti-histone centromere Jo-1 Scl-70 SLE ＞95﹪ 50-80﹪ 25-40﹪ 26-45﹪ 30-40﹪ 0-15﹪ 25-60﹪ －   Drug-induced lupus Rare 90﹪ Mixed connective tissue disease 99﹪ 100﹪ 0-20﹪ Rheumatoid arthritis 20-50﹪ 10﹪ 5-7﹪ 20﹪ Sjogren's syndrome 20-70﹪ 33-60﹪ Scleroderma 30-50﹪ 22﹪ 0-7﹪ (CREST) 89-90﹪ 70% Polymyositis 20-30﹪ 0-9﹪ 25-50﹪

Antinuclear antibodies (ANAs) 對抗: nucleic acids (DNA, RNA) nucleoproteins found in the connective tissue diseases

Antinuclear antibodies (ANAs) 低倍的ANA陽性1: 40 or 1: 80，在很多疾病及年老的正常人皆可發生。 如果是高倍陽性(>=640倍)，常是SLE、scleroderma或MCTD。故高倍與臨床有密切關係，而低倍陽性並不是假陽性，是與臨床疾病比較沒有特殊的關係。 感染、發炎、腫瘤甚至正常人也可能升高。

Antinuclear antibodies (ANAs) 陽性： 檢體血清中細胞核之螢光染色程度，亮於陰性品管測定孔，且有明顯可辨別之螢光形態，則被認定是陽性，且重複被確認依1:80，1:160，1:320..等被稀釋。每次檢驗，均須同時進行陽性對照組及陰性對照組。陰性對照組應對Hep-2細胞無任何特別之螢光反應，而陽性對照組對Hep-2細胞有明顯之螢光反應。

Antinuclear antibodies (ANAs) Homogeneous (diffuse): 1. Anti-ds DNA, Histones, Nucleosomes, Ku -- SLE, drug-induced SLE

Antinuclear antibodies (ANAs) Speckled pattern: 1. Anti-RNP, Anti-Sm (ribonucleoprotein, a component of splicesome) -- MCTD, SLE 2. SSA (Ro)/ SSB (La) (transcription termination factor) -- Sjögren’s syndrome -- Subacute cutaneous lupus

Antinuclear antibodies (ANAs) Nucleolar patterns: 1. Homogenous nucleolar pattern- anti-PM/ Scl --Systemic sclerosis, Polymyositis or Dermatomyositis 2. Clumpy nucleolar pattern- anti-fibrillarin -- Systemic sclerosis 3. Fine punctate nucleolar pattern- Antibodies to RNA polymerase

Antinuclear antibodies (ANAs) Peripheral (rim): Anti-ds-DNA: SLE

Antinuclear antibodies (ANAs) Centromere pattern: Anti-centromere antibodies -- CREST syndrome, Sjögren’s syndrome CREST syndrome: Calcinosis, Raynaud’s phenomenon , Esophageal dysmotility, Sclerodactyly, Telangiectasia

Antinuclear antibodies (ANAs) Cytoplasmic pattern: -- may be related to primary biliary cirrhosis (PBC)

Antineutrophil cytoplasmic antibodies (ANCA) c-ANCA: cytoplasmic staining 對抗proteinase 3 Wegener's Granulomatosis (90%) Microscopic polyarteritis

Antineutrophil cytoplasmic antibodies (ANCA) p-ANCA: peri-nuclear stain against myeloperoxidase and against elastase seen in patient with GN, various forms of vasculitis and collagen vascular disease

Anti-ds DNA Antibody 單股DNA抗體較無疾病的特殊性，雙股DNA抗體(anti-ds DNA)則是SLE的特殊抗體之一。 50-80 % of SLE patients In SLE, anti-ds DNA antibody strongly correlate with nephritis and disease activity

Anti-phospolipid antibodies Lupus anticoagulant, Anticardiolipin Ab, Anti-beta2-glycoprotein-I Ab, Antiphosphotidyl serine Ab (APTS) Thromboembolism events: CVA, AMI, Pulmonary embolism, DVT, Ischemic bowel Recurrent abortion, Infertility, Pre-eclampsia Hemolytic anemia, thrombocytopenia SLE CNS involvement, Mononeuropathy multiplex Raynaud’s phenomenon, Livedo reticularis

Anti-Ro & La Antibody 30-40% of SLE patients possess anti-Ro activity 0-15 % of SLE possess anti-La SS-B/La大部分存在於紅斑性狼瘡或Sjogren’s syndrome之病人，一般若SS-B/La陽性的病人，會同時有SS-A/Ro抗體，反之則不然。

Anti-Ro & La Antibody Anti-Ro is associated with photosensitive rash, subacute cutaneous lupus and the neonatal lupus syndrome In SLE, anti-La correlates with late-onset SLE, secondary Sjogren's syndrome, the neonatal lupus syndrome

Anti-Ro & La Antibody Anti-Ro (SS-A) antibodies recognize a set of primarily cytoplasmic ribonucleoproteins consisting of the 60-kDa Ro60 antigen and a single molecule of human Y1, Y3, Y4, or Y5 RNA The 47-kDa La (SS-B) antigen associates transiently with the precursors of several small RNAs synthesized by RNA polymerase III, including Ro60 ribonucleoproteins, and protects them from exonucleases. La is a termination factor for RNA polymerase III

Anti-Sm antibody Specific antibodies in the diagnosis of SLE 10 to 25 % of SLE patients Anti-Sm and anti-RNP autoantibodies recognize a set of small nuclear ribonucleoproteins (snRNPs) containing highly structured, uridine-rich small RNAs (U1, U2, U4, U5, and U6 RNAs) involved in the splicing of messenger RNA Sm及RNP抗原是mRNA製造過程所需要的Splicesome成員，由核內小RNA(SnRNA)及蛋白質組合而成。抗體作用的對象是蛋白質而不是RNA。

Anti-Sm antibody Sm及RNP抗體／抗原系統最初是以免疫擴散法定義出兩種不同的抗體，可與Sn RNA-蛋白質複合體 U1、U2、U4／U6、U5等結合 RNP抗體可使U1RNP 免疫沉澱(immuno precipitation)下來，而Sm抗體可使所有的SnRNP沉澱下來。約有20%-30%的SLE病人有Sm抗體，此抗體絕大部分發現於SLE的病人身上

Anti-RNP antibody 100 % in MCTD、high-titer 26 to 45 % of SLE lower titers in several other rheumatic diseases, including primary Raynaud’s phenomenon, rheumatoid arthritis, and scleroderma

Nucleic acid components of some autoantigens

Anti- histone antibody Histone好比線軸承，供DNA纏繞，依分子量大小分別是H1、H2A、H2B、H3及H4 In the 20 to 60 % of SLE patients, predominantly target the H1 and H2B proteins appear uniformly in drug-induced lupus low frequency in other diseases

Anti- Jo-1 antibody 20 to 50 % of polymyositis 皮肌炎或多發性肌炎主要是靠臨床表現，加上一些檢查（GOT GPT及CPK的升高，肌電圖異常及肌肉切片等）來診斷 Jo-1抗體大部分只存在於與惡性腫瘤無關的多發性肌炎，而Mi-2則與皮肌炎有密切的相關性，當Jo-1 Ab存在時較易出現肺部之侵犯

Anti- Scl 70 antibody Anti- Scl 70 antibody是對抗topoisomerase I topoisomerse之作用是將緊密扭繞（super-coiled）的雙股ＤＮＡ放鬆，其分子量是100000，但於萃取過程被切成較小分子，其中之一是具有抗原的70ＫＤ片段所以命名Scl-70，此一抗體可在Scleroderma病人測得，具有高度的特異性

Autoantibodies in scleroderma Anti-centromere antibody: limited cutaneous disease Anti-Scl-70 antibody: diffuse skin disease and interstitial lung disease Anti-RNA polymerase III antibody: worse prognosis, extensive skin thickening and renal crisis

C3 Decreased C3 levels: associated with most active diseases with immune complex formation

C3 Decreased C3 levels: Active SLE Absence of C3b inactivator factor Acute post-streptococcal glomerulonephritis Membranoproliferative glomerulonephritis End-stage liver disease Increased levels: found in numerous inflammatory states.

C4 Decreased C4 levels: Acute SLE Early glomerulonephritis Cryoglobulinemia Inborn C4 deficiency Hereditary angioneurotic edema Increased levels: found in numerous inflammatory states.

全身性紅斑狼瘡病患常出現各種自體抗體 Anti-dsDNA – lupus nephritis (84.4) Anti-Ro/SSA - congenital heart block Anti-Ribosomal P – psychosis (88.9) (neuropsychiatric) Anti-Neuronal – seizure Anti-Sm – specificity (最具特異性) (87.1; 85.7; 84.10) (Anti-dsDNA?) Anti-phospholipid Ab--spontaneous abortion, neuropsychiastric lesions (CNS involvement) (88.9)

全身性紅斑狼瘡病患常出現各種自體抗體 Anti-phospholipid antibody--Libman-Sachs氏心內膜炎(Libman-Sachs endocarditis) (88.6) Anti-Ro/SSA- 亞急性皮膚性紅斑狼瘡症(subacute cutaneous lupus erythematosus) --甚少侵犯中樞神經及腎臟，預後甚佳，常出現廣泛的皮膚病變及關節炎 (88.7) Anti-histone Ab – drug-induced lupus (87.2) (86.3) (85.3)

Rheumatoid Factor an autoantibody that recognize abnormally glycosylated IgG seropositive or seronegative diseases: ‘sero’ means rheumatoid factor RF主要是一種對抗IgG的IgM抗體，但也可以是IgG、IgA、IgD或IgE。

Rheumatoid factor in rheumatoid arthritis 診斷RA的criteria中的一項 High titers of RF, particularly IgG RF, are a risk factor for the development of vasculitis elevated IgA RFs may correlate with bone erosions, vasculitis, and a more severe disease course

Anti-citrullinated protein antibodies (ACPA) or anti-cyclic citrullinated protein antibodies (anti-CCP) During inflammation, arginine residues in proteins can be enzymatically converted into citrulline ones (a process called citrullination), and, if their shapes are significantly altered, the proteins may be seen as antigens by the immune system The most specific marker for the diagnosis of rheumatoid arthritis

Anti-citrullinated protein antibodies (ACPA) or anti-cyclic citrullinated protein antibodies (anti-CCP)