An improved, ultrasensitive method for the detection of IgM oligoclonal bands in cerebrospinal fluid

A new, 10-fold more sensitive method, based on an improved immunofixation technique, has been devised to detect oligoclonal IgM bands in unconcentrated cerebrospinal fluid (CSF). Using agarose gel electrophoresis, 5 microliters of an unconcentrated sample containing oligoclonal bands was separated and blotted on to a polyvinyldifluoride membrane. To visualise the pattern, a peroxidase-labelled double-antibody technique was used. No prior concentration of CSF was needed and the process required only 5 h. The technique may prove very useful in diagnosing an early intrathecal immune response.

Cerebrospinal fluid oligoclonal IgM in multiple sclerosis: analytical problems and clinical limitations

A method for detecting cerebrospinal fluid (CSF) oligoclonal IgM is described. Concentrated CSF was separated by agarose isoelectric-focusing and blotted with poly(vinyldifluoride). A double-antibody immunoperoxidase technique with avidin-biotin amplification was used to stain IgM. Special conditions were required to avoid cross-reaction with IgG. The method was applied to 99 patients on whom oligoclonal IgG analysis was performed. Positive IgM results occurred in 17 of the 27 patients positive for oligoclonal IgG, and in two patients negative for oligoclonal IgG, neither of whom had multiple sclerosis (MS). Fifteen of the patients positive for oligoclonal IgM had some IgM bands in their sera. Oligoclonal IgM was not found in the CSF of suspected MS patients without oligoclonal IgG, but occurred in several patients with oligoclonal IgG due to other diseases. As a test for MS, oligoclonal IgM was less sensitive than oligoclonal IgG and did not improve specificity.

CSF oligoclonal IgG bands in a patient with torsion dystonia

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Tarsal tunnel syndrome secondary to intraneural ganglion

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Differential oligoclonal band patterns on polyvinyldifluoride membranes

We report a novel observation which has been reproducibly noted whilst studying immunoglobulin G binding to antigen immobilized on polyvinyldifluoride membranes. In some samples we have observed a difference between the pattern of oligoclonal bands on the front surface when compared to the reverse side of the membrane. We postulate that this observation results from differing affinities of the specific antibody binding to the antigen immobilised on the membrane. High affinity antibody will bind to antigen on the surface of the membrane next to the gel, while lower affinity antibody appears to diffuse through to the reverse side of the membrane.

Immunoblotting techniques with picogram sensitivity in cerebrospinal fluid protein detection

Agarose isoelectric focusing followed by blotting with nitrocellulose, nylon or polyvinylidene difluoride membranes, and immunochemical detection of cerebrospinal fluid IgG with various combinations of antisera, was evaluated. Polyvinylidene difluoride proved to be an easy-to-handle and reliable membrane for protein blotting. Among immunochemical visualization reactions, the most sensitive employed biotinylated goat anti-human IgG followed by streptavidin colloidal gold conjugate and silver enhancement in 20% w/v urea, allowing a sensitivity of less then 1 picogram IgG/band.