Chui S H, Lam C W, Lai K N
Department of Chemical Pathology and Medicine, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin.
Clin Chem. 1990 Mar;36(3):501-2.
We describe an enzyme-linked immunosorbent assay for determination of light-chain ratios for IgG, IgA, and IgM in serum. A commercial serum with known overall kappa and lambda concentrations was used as standard. To capture the respective immunoglobulins, we used antibodies to gamma, lambda and mu chains coated onto microtiter plates. Peroxidase-conjugated anti-kappa and anti-lambda chain antisera were reacted with light chains on the captured immunoglobulins, and the amount of enzyme bound was monitored with o-phenylenediamine and urea-hydrogen peroxide as substrates. Calculation of absorbance ratios allowed determination of kappa and lambda chain concentrations of individual immunoglobulins in the standard and samples. Within-run and between-run CVs (n = 25) ranged from 5.9% to 13.0% for "high," "normal," and "low" kappa/lambda ratios for IgG, IgA, and IgM. The thoroughness of light-chain detection, expressed as, e.g., (IgA kappa + IgA lambda)/(total IgA), for 150 sera was 91-110%. The detection limit was 1 microgram/L. Reference intervals (mean +/- SD) for kappa/lambda ratios in sera from 100 apparently healthy adults were 2.34 +/- 0.80 for IgG, 1.59 +/- 0.40 for IgA, and 1.86 +/- 0.76 for IgM.
我们描述了一种用于测定血清中IgG、IgA和IgM轻链比例的酶联免疫吸附测定法。使用一种已知总κ和λ浓度的商业血清作为标准品。为捕获相应的免疫球蛋白，我们使用包被在微量滴定板上的抗γ、λ和μ链抗体。将过氧化物酶偶联的抗κ和抗λ链抗血清与捕获的免疫球蛋白上的轻链反应，并用邻苯二胺和尿素 - 过氧化氢作为底物监测结合的酶量。通过计算吸光度比值可以测定标准品和样品中各个免疫球蛋白的κ和λ链浓度。对于IgG、IgA和IgM的“高”、“正常”和“低”κ/λ比值，批内和批间变异系数（n = 25）范围为5.9%至13.0%。以例如（IgA κ + IgA λ）/（总IgA）表示的150份血清的轻链检测完整性为91 - 110%。检测限为1微克/升。100名明显健康成年人血清中κ/λ比值的参考区间（平均值±标准差）为：IgG为2.34±0.80，IgA为1.59±0.40，IgM为1.86±0.76。
