Sobey W J, Beer S F, Carrington C A, Clark P M, Frank B H, Gray I P, Luzio S D, Owens D R, Schneider A E, Siddle K
Department of Clinical Biochemistry, University of Cambridge, Addenbrooke's Hospital, U.K.
Biochem J. 1989 Jun 1;260(2):535-41. doi: 10.1042/bj2600535.
Monoclonal antibody-based two-site immunoradiometric assays are described for human insulin, proinsulin, 65-66 split and 32-33 split proinsulin. The detection limits of the assays lie in the range 0.8-2.5 pM. The assays for 65-66 and 32-33 split proinsulins do not distinguish between these substances and their respective C-terminal di-desamino derivatives. The assay of 65-66 split proinsulin does not cross-react with insulin, proinsulin or 32-33 split proinsulin. This material was undetectable (less than 1.0 pM) in plasma taken after an overnight fast in eight normal male subjects and the maximum individual concentration reached in plasma taken during an oral glucose tolerance test of these subjects was 3.8 pM. The proinsulin assay cross-reacted 66% with 65-66 split proinsulin but not with insulin or 32-33 split proinsulin. The 32-33 split proinsulin assay cross-reacted 84 and 60% with proinsulin and 65-66 split proinsulin respectively. The insulin assay cross-reacted 5.3, 62 and 5.0% with intact proinsulin, 65-66 split proinsulin and 32-33 split proinsulin respectively. The very low concentration of 65-66 split proinsulin meant that this derivative did not interfere significantly with the specificity of the assays of proinsulin and insulin. The concentration of 32-33 split proinsulin could be calculated by subtracting the cross-reactivity of the measured proinsulin. The mean concentrations of insulin, proinsulin and 32-33 split proinsulin in eight young male subjects in the fasting state were (pM +/- S.E.M.) 20 +/- 0.3, 2.3 +/- 0.3 and 2.1 +/- 0.7 and at the maximum reached during an oral glucose tolerance test, 150 +/- 26, 9.9 +/- 1.4 and 19.7 +/- 6.0 respectively.
本文描述了基于单克隆抗体的双位点免疫放射分析方法，用于检测人胰岛素、胰岛素原、65-66裂解胰岛素原和32-33裂解胰岛素原。这些分析方法的检测限在0.8-2.5 pM范围内。65-66和32-33裂解胰岛素原的分析方法无法区分这些物质及其各自的C端双去氨基衍生物。65-66裂解胰岛素原的分析方法与胰岛素、胰岛素原或32-33裂解胰岛素原无交叉反应。在8名正常男性受试者过夜禁食后采集的血浆中未检测到该物质（低于1.0 pM），在这些受试者口服葡萄糖耐量试验期间采集的血浆中达到的个体最大浓度为3.8 pM。胰岛素原分析方法与65-66裂解胰岛素原的交叉反应率为66%，但与胰岛素或32-33裂解胰岛素原无交叉反应。32-33裂解胰岛素原分析方法与胰岛素原和65-66裂解胰岛素原的交叉反应率分别为84%和60%。胰岛素分析方法与完整胰岛素原、65-66裂解胰岛素原和32-33裂解胰岛素原的交叉反应率分别为5.3%、62%和5.0%。65-66裂解胰岛素原的极低浓度意味着该衍生物对胰岛素原和胰岛素分析方法的特异性无显著干扰。32-33裂解胰岛素原的浓度可通过减去所测胰岛素原的交叉反应率来计算。8名年轻男性受试者在禁食状态下胰岛素、胰岛素原和32-33裂解胰岛素原的平均浓度（pM±标准误）分别为20±0.3、2.3±0.3和2.1±0.7，在口服葡萄糖耐量试验期间达到的最大值分别为150±26、9.9±1.4和19.7±6.0。
