Analysis of immune complexes of cerebrospinal fluid by two-dimensional gel electrophoresis.

From the cerebrospinal fluid of 32 patients with different neurological diseases immune complexes were isolated using protein A-Sepharose. The isolated heavy and light chains and their constituents were analyzed by two-dimensional gel electrophoresis. In addition to immunoglobulins, some proteins such as albumin, apolipoprotein A-I and a number of unknown proteins were detected in all preparations. A complex consisting of three proteins with molecular masses between 52-55 kDa reacted slightly with polyclonal antibodies to glial fibrillary acidic protein. Whether the linkage between these antigens and the Ig is due to the Fab region or the Fc region remains unknown in our study. In some immune complexes of neurological diseases such as amyotrophic lateral sclerosis, astrocytoma and multiple sclerosis, differences are easily recognizable in the gel pattern.