Kahn S N, Bina M
Department of Pathology & Laboratory Medicine, University of Pennsylvania, Philadelphia 19104.
Clin Chem. 1988 Aug;34(8):1633-5.
Detection and characterization of small IgM paraproteins by immunoelectrophoresis are often difficult because of (a) slow diffusion of the macromolecular immunoglobulin, and (b) the obscuring of the light chain, especially kappa, by the light chains of background polyclonal immunoglobulin (the "umbrella effect"). Various methods of sample pretreatment have been tried in an attempt to overcome this problem. Using immunofixation electrophoresis (IFE), we were able to detect and characterize IgM paraproteins in serum at concentrations as low as 0.25 g/L, even when the polyclonal immunoglobulin background was increased. With routine IFE, our laboratory identified 58 patients with IgM paraproteinemia in a four-year period. In 36, the paraproteins were present at less than 5 g/L; 10 of these were detectable only by IFE.
通过免疫电泳检测和鉴定小IgM副蛋白往往很困难，原因如下：(a) 大分子免疫球蛋白扩散缓慢，以及 (b) 背景多克隆免疫球蛋白的轻链（尤其是κ链）会掩盖副蛋白的轻链（“伞效应”）。人们尝试了各种样品预处理方法来克服这个问题。使用免疫固定电泳（IFE），我们能够检测和鉴定血清中浓度低至0.25 g/L的IgM副蛋白，即使多克隆免疫球蛋白背景增加时也是如此。通过常规IFE，我们实验室在四年期间鉴定出58例IgM副蛋白血症患者。其中36例患者的副蛋白浓度低于5 g/L；其中10例仅通过IFE才能检测到。
