摘要
目的检测抗钙蛋白酶抑素C端Ⅳ区抗体(ACAST-DⅣ)在类风湿关节炎(RA)中的阳性率,探讨ACAST-DⅣ在RA中的意义。方法人工合成已鉴定的钙蛋白酶抑素C端Ⅳ区A、B、C3个抗原表位多肽,分别以A、B、C肽(均为9肽)为抗原,并将3个肽稀释后混合作为Ⅳ区抗原。用酶联免疫吸附试验(ELISA)分别检测191例RA、147例其他风湿病患者和106名正常人血清中抗A、B、C肽和ACAST-DⅣ的水平及阳性率。同时分析ACAST-DⅣ与类风湿因子(RF)、抗环瓜氨酸多肽(CCP)抗体相关性,比较ACAST-DⅣ阳性组与阴性组的血沉(ESR)、RF、C反应蛋白(CRP)和日常生活能力(HAQ)。结果RA患者ACAST-DⅣ抗原表位A、B和C肽的吸光度值水平和阳性率均明显高于其他风湿病和正常对照组(P<0.01),对RA诊断的敏感性分别为33.3%、28.9%和46.7%;特异性分别为96.7%、96.7%和87.8%。ACAST-DⅣ(3个肽混合)在RA、骨关节炎(OA)、系统性红斑狼疮(SLE)、脊柱关节病(SPA)和正常对照组中的阳性率分别为74.3%、2.8%、0、0和6.6%(P<0.01)。ACAST-DⅣ对RA诊断的敏感性和特异性为74.3%和96.3%;阳性预测值92.6%,阴性预测值85.8%。ACAST-DⅣ与抗CCP抗体之间有相关性(P<0.05),与RF之间无明显相关。ACAST-DⅣ阳性组ESR明显高于阴性组(P<0.05),但CRP、RF和HAQ两组之间差异无统计学意义。结论ACAST-DⅣ对RA诊断有较好的敏感性(74.3%)和特异性(96.3%)。ACAST-DⅣ与抗CCP抗体相关,且该抗体阳性患者的ESR明显升高,可能与疾病活动有关。ACAST-DⅣ可作为RA的血清学诊断指标。
Objective To explore the diagnostic value of autoantibodies against C-terminal domain Ⅳ of human calpastatin （ACAST-DⅣ） in patients with rheumatoid arthritis （RA）. Methods The synthesized three epitopes of C-terminal domain Ⅳ of calpastatin, namely DKDLDDALD （residue, 564-572, A peptides）, DTIPPEYRH （residue, 612-620, B peptides）, QDPIDALSG （residue, 648-656, C peptides） and A＋B＋C peptides mixing as the DⅣ antigen. The anti-A,B,C peptide autoantibodies and ACAST-DⅣ were detected by enzyme-linked immunosorbent assay （ELISA） in 191 patients with RA, 147 patients with other rheumatic diseases and 106 healthy controls. To compare the correlation ACAST-DⅣ with the anti-cyclic citrullinated peptide （CCP） antibody, rheumatoid factor （RF）, erythrocyte sedimentation rate （ESR）, C-reactive protein （CRP） and health assessment questionnaire （HAQ）. Results The sensitivity of autoantibodies against A,B,C peptides epitopes of domain Ⅳ calpastatin was 33.3% （30/90）, 28.9% （26/90） and 46.7% （42/90） respectively, which were higher than other rheumatic diseases and healthy controls （P〈0.01）. The specificity of autoantibedies against A, B, C peptides was 96.7%, 96.7% and 87.8%, respectively. The ACAST-D Ⅳ were found in the sera of 75 of 101 patients （74.3%） with RA, in contrast, the ACAST-DⅣ were found in the sera of only 1 of 36 （2.8%） patients with osteoarthritis （OA）, 0 of 38 patients with systemic lupus erythematosus （SLE）, 0 of 13 patients with spondyloarthropathy （SPA） and 5 of 76 （6.6%） healthy control. The ACAST-D Ⅳ also showed high specificity （96.3%）. Correlations between ACAST-DⅣ and anfi-CCP was found. No correlation was found between ACAST-DⅣ and RF. The ESR of ACAST-DⅣ positive group was higher than that of negative patients with B.A. No statistically significant difference was found in CRP, RF and HAQ between ACAST-DⅣ positive and negative patients with B.A. Conclusion ACAST-D Ⅳ presents a high s
出处
《中华风湿病学杂志》
CAS
CSCD
2006年第5期280-283,共4页
Chinese Journal of Rheumatology
基金
安徽省卫生厅科研基金资助项目(2002A009)
关键词
类风湿关节炎
肽水解酶类
钙蛋白酶抑素
抗钙蛋白酶抑素抗体
Arthritis, rheumatoid
Peptide hydrolases
Antibodies to calpastatin
Anti-cyclic citrullinated peptide, enzyme-linked immunosorbent assay
