心肌肌钙蛋白－IRIA建立及初步临床应用

DEVELOPMENT OF CARDIAC TROPONIN-I RADIOIMMUNOASSAY AND PRELIMINARY RESULTS IN CLINICAL APPLICATION

从人心肌组织中提纯并鉴定了心肌肌钙蛋白－１（ＣＴｎＩ），免疫新西兰纯系兔而获特异性抗血清，其亲和常数Ｋａ值为４．１×１０１０Ｌ／ｍｏｌ．Ｉｏｄｏｇｅｎ法制１２５Ｉ－ＣＴｎＩ，比活度为３６５９ＧＢｑ／ｇ．建立了ＣＴｎＩ双抗体ＲＩＡ，标准曲线ＥＤ５０为６．４±０．３４μｇ／Ｌ（ｘ±ｓ，ｎ＝８），灵敏度达１．５μｇ／Ｌ，工作范围为２－６４μｇ／Ｌ，批内、批间ＣＶ分别为２．１％－５．７％（ｎ＝８）和５．４％－９．０％（ｎ＝４），方法回收率为９０．１％－９５．３％．与骨胳肌肌钙蛋白－Ｉ（ＳＴｎＩ）未见交叉反应，测定８７例正常人血清ＣＴｎＩ浓度为２．１７±０．６６μｇ／Ｌ（ｘ±ｓ），８０例有关疾病患者ＣＴｎＩ血清浓度测定表明该方法对诊断心肌细胞损伤具有心肌特异性．并且ＣＴｎＩ于心肌细胞损伤后在血清中出现时间早，维持时间长，是一个理想的心肌细胞损伤标志物．

Abstract A double antibody radioimmunoassay (RIA) was developed to measure cardiac troponin-I (CTnI) in serum. CTnI from fresh human myocardium was purified and identified. Antisera against CTnI were raised in NZ rabbits with affinity constant (Ka) 4.1 × 10-10L/mol. Iodination of CTnI was carried out with iodogen. The specific activity of the product was 3659 GBq/g. The ED40 was 6.4±0.34μg/L (x±s, n=8) from standard curves. The sensitivity was 1.5μg/L and the assay covered the range 2￣ 64μg/L for CTnI. The intra-assay and inter-assay coefficient of variation (CV) were 2.1% ￣5.7% (n=8) and 5.4%￣9.9% (n=4) respectively. The assay recovery was 90.1%￣95.3%.Non-immunochemical cross reactivity with skeletal troponin-I(STnI) was observed. The normal value was 2.17 ± 0.66μg/L (x ± s) in sera of 87 normal persons.