Detection of oligoclonal IgG bands in cerebrospinal fluid by isoelectric focusing on thin layer agarose gels.

The detection of oligoclonal bands of IgG in cerebrospinal fluid by isoelectric focusing is a useful aid in the diagnosis of multiple sclerosis. At present, this test is performed on polyacrylamide gels which are technically very difficult to prepare and are not suitable for the routine laboratory. A technique is described for isoelectric focusing on thin layer agarose gels which permits oligoclonal banding detection in the routine laboratory in four hours. The advantages of this procedure over isoelectric focusing on polyacrylamide gels include: (a) it takes less time (four hours compared with at least 24 hours); (b) it requires less specimen (2.5 ml compared with reference laboratory requirements of at least 4 ml); (c) it is technically easier to perform; and (d) it can be done routinely in the clinical laboratory.