Dalbosco I S, Vieria J G, Nishida S K, Lombardi M T, Moisés R C, Coifman R, Russo E M
Disciplina de Endocrinologia, Universidade Federal de São Paulo, Brasil.
Braz J Med Biol Res. 1996 Feb;29(2):193-9.
We describe a time-resolved fluoroimmunoassay specific for human proinsulin using a combination of two high-affinity monoclonal antibodies, one against insulin and the other specific for intact proinsulin and for split 65-66 and des 64-65 proinsulin forms. The assay employs only 200 microl of serum, with a detection limit of 0.1 pmol/l. The intra-assay variation coefficient was less than 3% between 3 and 1000 pmol/l. There was 0% cross-reaction with insulin, C-peptide, split 32-33 and des 31-32 proinsulin. Serum concentration of proinsulin was analyzed in 50 subjects during an oral glucose tolerance test (10 non-obese control, 10 obese controls, 10 subjects with impaired glucose tolerance, 10 patients with type II diabetes mellitus (DM) and fasting blood glucose (FBG) < 140 mg/dl, and 10 patients with type II DM and FBG > 150 mg/dl). Mean fasting serum proinsulin levels measured by this assay in non-obese controls (0.84 - 0.90 pmol/l; 0.1-2.4 pmol/l) were lower than the results reported by other investigators. There was an increase of proinsulin related to obesity and increased glucose levels, suggesting that proinsulin levels increase with insulin resistance.
我们描述了一种用于人胰岛素原的时间分辨荧光免疫测定法，该方法使用了两种高亲和力单克隆抗体的组合，一种针对胰岛素，另一种对完整的胰岛素原以及裂解的65-66和缺失64-65的胰岛素原形式具有特异性。该测定法仅需200微升血清，检测限为0.1皮摩尔/升。在3至1000皮摩尔/升之间，测定内变异系数小于3%。与胰岛素、C肽、裂解的32-33和缺失31-32的胰岛素原无交叉反应。在口服葡萄糖耐量试验期间，对50名受试者的血清胰岛素原浓度进行了分析（10名非肥胖对照者、10名肥胖对照者、10名糖耐量受损受试者、10名空腹血糖（FBG）<140毫克/分升的II型糖尿病（DM）患者以及10名FBG>150毫克/分升的II型DM患者）。通过该测定法在非肥胖对照者中测得的平均空腹血清胰岛素原水平（0.84 - 0.90皮摩尔/升；0.1 - 2.4皮摩尔/升）低于其他研究者报告的结果。胰岛素原水平与肥胖和血糖水平升高相关，表明胰岛素原水平随胰岛素抵抗增加而升高。
