Okada Y, Yokono K, Katsuta A, Yoshida M, Morita S, Irino H, Goto T, Baba S, Roth R A, Shii K
Hyogo Institute of Clinical Research, Akashi, Japan.
Anal Biochem. 1998 Mar 15;257(2):134-8. doi: 10.1006/abio.1997.2446.
A method to detect the biological activity of serum insulin has been developed. This method, called a bioactive insulin assay, determines the ability of serum insulin to stimulate the autophosphorylation of insulin receptors in an intact cell system. For this, intact Chinese hamster ovary cells which overexpress the human insulin receptor are treated with serum and then lysed. Autophosphorylation of the insulin receptors is then measured by a two-site immunofluorometric assay using monoclonal anti-insulin receptor antibodies and europium-labeled anti-phosphotyrosine antibodies. The detection limit of this assay is 1 microU/ml of insulin. Dilution and recovery test inter- and intraassay coefficient variations are permissible. The amount of insulin determined by this assay correlated well with the amount of insulin detected by a traditional immunological assay for insulin (r = 0.94, P < 0.001). In the case of a mutant insulin, the insulin from a Wakayama subject, the biologically active insulin was found to constitute 9% of the immunologically reactive insulin. Since this assay specifically measures the amount of biologically active insulin present in serum, it should be particularly useful in monitoring active insulin in patients with various mutant insulins.
已开发出一种检测血清胰岛素生物活性的方法。这种方法称为生物活性胰岛素测定法，可在完整细胞系统中测定血清胰岛素刺激胰岛素受体自磷酸化的能力。为此，用血清处理过表达人胰岛素受体的完整中国仓鼠卵巢细胞，然后进行裂解。然后使用单克隆抗胰岛素受体抗体和铕标记的抗磷酸酪氨酸抗体，通过双位点免疫荧光测定法测量胰岛素受体的自磷酸化。该测定法的检测限为1微单位/毫升胰岛素。允许进行稀释和回收试验的批间和批内系数变异。通过该测定法测定的胰岛素量与通过传统胰岛素免疫测定法检测到的胰岛素量相关性良好（r = 0.94，P < 0.001）。对于突变胰岛素，即和歌山县一名受试者的胰岛素，发现生物活性胰岛素占免疫反应性胰岛素的9%。由于该测定法专门测量血清中存在的生物活性胰岛素的量，因此在监测各种突变胰岛素患者的活性胰岛素方面应该特别有用。
