EXON-2 CONTAINING MYELIN BASIC-PROTEIN (MBP) TRANSCRIPTS ARE EXPRESSED IN LESIONS OF EXPERIMENTAL ALLERGIC ENCEPHALOMYELITIS (EAE)

Exon 2 containing myelin basic protein (MBP) transcripts are expressed during developmental myelination in mice and humans, and during remye lination subsequent to virally induced demyelination in adult mice. Si nce remyelination characterizes CNS lesions during experimental allerg ic encephalomyelitis (EAE) and multiple sclerosis (MS), we investigate d whether exon 2 containing isoforms of MBP are expressed in EAE lesio ns during relapsing disease. Exon 2 containing MBP transcripts were de tected by in situ hybridization in 17 of 52 EAE mice and in 16 of 30 m ice at the peak of the first or second episode of paralysis. Thus exon 2 containing MBP transcripts are expressed in lesions of the CNS duri ng active phases of chronic relapsing autoimmune disease. Implications of these findings with respect to future therapies aimed toward enhan cing remyelination in EAE and, possibly MS, are discussed.