Sindic C J, Van Antwerpen M P, Goffette S
Laboratoire de Neurochimie, Université Catholique de Louvain et Cliniques, Universitaires Saint-Luc, Bruxelles, Belgium.
Clin Chem Lab Med. 2001 Apr;39(4):333-40. doi: 10.1515/CCLM.2001.052.
In normal conditions, albumin and immunoglobulin (Ig)G in the cerebrospinal fluid (CSF) originate from the blood, and there is no antibody production within the central nervous system. Up to 20% of CSF proteins are intrathecally synthesized, but the major fraction is blood-derived. The CSF/serum albumin quotient (QAlb) is the best marker of the blood-CSF barrier function. The corresponding immunoglobulin quotients (QIGG, QIGA, QIGM) are not linearly related to QAlb and their correlations are defined by an hyperbolic equation. This equation is used to discriminate between a blood-derived and a locally produced fraction of immunoglobulins in case of an intrathecal humoral immune response. The detection of CSF-specific oligoclonal IgG is more sensitive than the quantitative comparison between QIGG and QAlb. A further step is the determination of antibody indices and the detection of specific oligoclonal antibodies by antigen-driven immunoblots. CSF analysis remains a cornerstone for the diagnosis of various neurological disorders, including multiple sclerosis and infectious diseases of the central nervous system.
在正常情况下，脑脊液（CSF）中的白蛋白和免疫球蛋白（Ig）G来源于血液，中枢神经系统内不产生抗体。高达20%的脑脊液蛋白质是鞘内合成的，但大部分是血液来源的。脑脊液/血清白蛋白商（QAlb）是血脑屏障功能的最佳标志物。相应的免疫球蛋白商（QIGG、QIGA、QIGM）与QAlb并非线性相关，它们的相关性由一个双曲线方程定义。在鞘内体液免疫反应的情况下，该方程用于区分免疫球蛋白的血液来源部分和局部产生部分。脑脊液特异性寡克隆IgG的检测比QIGG和QAlb之间的定量比较更敏感。进一步的步骤是确定抗体指数，并通过抗原驱动的免疫印迹检测特异性寡克隆抗体。脑脊液分析仍然是诊断各种神经系统疾病的基石，包括多发性硬化症和中枢神经系统感染性疾病。
