Molé C M, Montagne P M, Béné M C, Faure G C
Laboratoire d'Immunologie, Faculté de Médecine de Nancy Vandoeuvre les Nancy, France.
Lab Invest. 1992 Jul;67(1):147-51.
Little is known of the light chains associated to heavy chains in secretions immunoglobulins. We investigated the partition of light chains in a mucosal fluid of easy access and major physiologic importance: human milk.
This study provides a sequential analysis of IgA, lambda and kappa chains levels in human milk during the first days of lactation. The levels of IgA alpha-chain and of lambda and kappa light chains of immunoglobulins were assayed in 162 samples of normal human milk collected during the first night of lactation, using a classical immunonephelometric assay. A specific enzyme-linked immunosorbent assay was developed to specifically measure the levels of IgA-linked light chains, yielding similar values. Ten samples of normal human serum obtained from healthy adults were tested in parallel.
The highest levels were observed during the first 3 days of lactation, and a plateau appeared for the three proteins after day 4. Mean lambda chains levels were consistently higher than these of kappa chains, resulting in a reversed kappa/lambda ratio, significantly different from the classical 2:1 serum ratio confirmed with this method on control samples.
This study indicates that milk immunoglobulins use an unusual partition of light chains, especially in IgA.
关于分泌型免疫球蛋白中与重链相关的轻链，人们了解甚少。我们研究了一种易于获取且具有重要生理意义的黏膜液——人乳中轻链的分布情况。
本研究对哺乳期头几天人乳中的 IgA、λ链和κ链水平进行了序列分析。使用经典免疫比浊法，对哺乳期第一晚采集的 162 份正常人乳样本中的 IgA α链以及免疫球蛋白的λ链和κ链水平进行了检测。开发了一种特异性酶联免疫吸附测定法来专门测量与 IgA 相关的轻链水平，得到了相似的值。同时对 10 份从健康成年人获取的正常血清样本进行了检测。
在哺乳期的前 3 天观察到最高水平，4 天后这三种蛋白质出现平台期。λ链的平均水平始终高于κ链，导致κ/λ比值倒置，与用该方法在对照样本上确认的经典血清 2:1 比值有显著差异。
本研究表明，乳汁免疫球蛋白使用了一种不同寻常的轻链分布，尤其是在 IgA 中。
