Experimental Autoimmune Encephalomyelitis – A Model for Multiple Sclerosis
Experimental autoimmune encephalomyelitis (EAE) is an autoimmune demyelinating disease that is induced in several ways in rat and mouse and is commonly used as a model of multiple sclerosis. Myelin oligodendrocyte glycoprotein (MOG) induced EAE produces a range of phenotypes which closely mimic human Multiple Sclerosis. These include prominent demyelination, axonal damage and chronic relapsing disease (Becanovic et al, 2003; PMID:12517974). As in MS, the highest rat of axonal injury is found during active demylelination with a low but significant amount also found in inactive demyelination plaques (Kornek et al, 2000; PMID:10880396)
Induction Agents
Spinal cord homogenate
Myelin proteolipid protein (PLP)
Myelin oligodendrocyte glycoprotein (MOG) – effects include prominent demyelination, axonal damage and chronic relapsing disease (Becanovic et al, 2003 PMID:12517974)
Myelin oligodendrocyte basic protein
Myelin basic protein (MBP) (Myelin membrane encephalitogenic protein)
Myelin-associated glycoprotein (MAG)
Adjuvant Commonly Used with Induction Agents
Freund’s adjuvant (CFA)
Induction has also been accomplished without use of an adjuvant (Stosic-Grujicic et all, 2004 (PMID:15030513)
DISEASE COURSE
The disease course can be defined as relapsing/remitting, monophasic, acute lethal, primary progressive (Becanovic et al 2003; PMID:12517974)
PHENOTYPE INDICES
Weakness and Paralysis Researchers often use a 5-point index for clinical assessment of EAE in rats although some researchers have expanded this. Descriptions and numbering vary from researcher to researcher, but generally follow these guidelines. Index Details
Demyelination
Inflammatory demyelinating lesions found in CNS and can be present in the absence of weakness, paralysis or other neurological manifestations (Dahlman et al, 1999; PMID:10072499). A four-point scale is sometimes used: 1 = perivascular/subpial demyelination, 2 = marked demyelination, 3 extended demyelination (more than half of the spinal cord white matter or one optic nerve or more than half of the cerebellar white matter), 4 = full demyelination of the spinal cord white matter, or both optic nerves or the cerebellar white matter (Becanovic et al, 2003, PMID:12517974)
Inflammatory response in CNS
Can occur withoutweakness, paralysis or other neurological manifestations (Dahlman et al, 1999, PMID:10072499)
Perivascular mononuclear infiltrates – may be quantitated by counting inflammatory foci with 20 or more aggregated mononuclear cells – indexed by 0 = no infiltrates, 1 = less than 10 inflammatory foci with 20 or more aggregated mononuclear cells, 2 = 11-30 foci 3 = more than 30 foci T cell infiltration – both CD8+ and CD4+ T cells present in spinal cord tissue Perivascular deposition of immunoglobulins
Researchers sometimes use a 4-point index for histological assessment of EAE in rats. Index Details
