Cerebrospinal fluid and serum oligoclonal IgG bands in rabbits with experiment allergic encephalomyelitis

Rabbits sensitized with whole nervous tissue or myelin basic protein (MBP) plus adjuvant and developing experimental allergic encephalomyelitis (EAE) were studied for the presence of oligoclonal immunoglobulin (Ig) bands in spinal fluid and serum. Samples obtained prior to sensitization and at the time of sacrifice were concentrated and subjected to agar gel electrophoresis. Of 11 rabbits receiving whole nervous tissue and developing severe clinical signs of EAE, 7 showed new oligoclonal Ig bands in spinal fluid and in serum obtained 19 days or more after sensitization. With MBP sensitization, 2 of 6 rabbits exhibited new spinal fluid bands, while all 6 rabbits studied demonstrated serum banding. The bands were identified as IgG by immunochemical studies using peroxidase-labeled antisera and by Staph. protein A absorption. The majority of animals showed no banding in presensitization samples. The finding of oligoclonal IgG in EAE reveals yet another immunologic correlation between EAE and the human demyelinating disease, multiple sclerosis.