Experimental autoimmune encephalomyelitis

Experimental autoimmune encephalomyelitis (EAE) is an animal model of brain inflammation. It is an inflammatory demyelinating disease of the central nervous system (CNS). It is mostly used with rodents and is widely studied as an animal model of the human CNS demyelinating diseases, including the disease multiple sclerosis. EAE was motivated by observations during the convalescence from viral diseases by Thomas M. Rivers, D. H. Sprunt and G. P. Berry in 1933. Their findings upon a transfer of inflamed patient tissue to primates was published in the Journal of Experimental Medicine article (Vol. 58, No. 1, pp. 39-56). It was previously referred to as Experimental allergic encephalomyelitis. EAE can be induced by inoculation with whole CNS tissue, purified myelin basic protein (MBP) or myelin proteolipid protein (PLP), together with adjuvants. It may also be induced by the passive transfer of T cells specifically reactive to these myelin antigens. EAE may have either an acute or a chronic relapsing course. Acute EAE closely resembles the human disease acute disseminated encephalomyelitis, while chronic relapsing EAE resembles multiple sclerosis. EAE is also the prototype for T-cell-mediated autoimmune disease in general.

EAE in mice
Demyelination is produced by injection of brain extracts (like myelin basic protein). The Blood-brain barrier is opened by injection of Freund adjuvant (adjuvant serves as BBB breaker).

Immune system of the animal ‘goes wild’ and multiple small disseminated lesions of demyelination (as well as micro-necroses) appear simultaneously in the brain.

Sharing some features, mostly demyelination, this model, first introduced in 1930s, cannot be considered equivalent to human MS. EAE either kills animals or leaves them with permanent disabilities, animals with EAE also suffer severe nerve inflammation, and the time course of EAE is entirely different to MS, being the main antigen (MBP) in charge.