Lessons from multiple sclerosis: models, concepts, observations.

Experimental autoimmune encephalomyelitis (EAE) is often termed "the" model of human multiple sclerosis (MS). This is, however, an oversimplification. MS is a multifaceted disorder, with no single experimental model representing the entire complexity of the human disease. On the other hand, EAE comes in numerous, distinct variants, which may reflect individual aspects of MS. This presentation reviews EAE variants and their usability as models for human MS. New transgenic models representing mechanisms determining spontaneous initiation, the course of central nervous system (CNS) autoimmunity, the distribution of lesions within the CNS and the cellular composition of the inflammatory infiltrate are discussed. Aspects of the early, inflammatory phase of MS plaque generation, in particular concerning the dynamics of immune cell invasion into the CNS, are also reviewed. Finally, the usability of EAE models for discovery and validation of MS drugs is discussed.