Experimental Autoimmune Encephalomyelitis (EAE)

Hooke has extensive experience with all commonly-used models of EAE. We can also work with you to develop new or modified models; our founder is Suzana Marusic, MD, PhD, a pioneer in development of adoptive transfer EAE models in C57BL/6 mice [3][4]; we believe Hooke is the leading EAE CRO in the world.

At Hooke we routinely run the following EAE models (click on any model for details and typical results):

For all EAE models, Hooke offers an extensive set of tissue collection and analysis options. Click here for more information.

Multiple sclerosis and EAE

Multiple sclerosis (MS) is a disease of the central nervous system (CNS) that affects over 2 million people; EAE is the most commonly used animal model of MS.

MS is an immune-mediated inflammatory disease affecting the central nervous system which causes demyelination of neurons, axonal damage, and neurodegeneration. CD4+ (Th1, Th17), CD8+ T cells, and B cells are believed to play a role in MS. The disease primarily affects white matter, but demyelination in gray matter also plays an important role. In most cases (> 80%) the disease begins with a relapsing/remitting course.

EAE is induced by CD4+ T cells specific for myelin-derived antigens, either generated after immunization or injected directly. However, B cells are known to be critical for disease development in the MOG1-125-induced EAE model in C57BL/6 mice.

As with MS in human patients, EAE is characterized by paralysis caused by CNS inflammation, demyelination of neurons, axonal damage, and neurodegeneration. Some EAE models exhibit remission and relapse (relapsing-remitting EAE). These similarities to MS make EAE an excellent animal model for evaluation of potential MS treatments. EAE is also considered a model of T cell mediated autoimmune diseases in general.

EAE development

EAE involves an initial wave of paralysis followed by full or partial recovery. In some models this initial recovery is followed by one or more relapses (relapsing-remitting EAE), or by chronic paralysis.

Chronic EAE
(MOG35-55 induced EAE in C57BL/6 mice) Partial recovery, chronic paralysis
Relapsing-remitting EAE
([Ser140]-PLP139-151 induced EAE in SJL mice) Recovery, relapse

Stress reduces susceptibility to EAE. Administration of treatment during the disease induction period (~0-10 days after immunization) postpones EAE onset and reduces severity, due to stress from compound administration and vehicle effects. The more frequent and stressful the administration, and the less tolerated the vehicle, the greater the impact on disease development.

In C57BL/6 mice the effects of stress are less pronounced if treatment starts after onset of paralysis.

Relative to disease-free controls, animals lose body weight during the acute phase of EAE, followed by partial recovery in the chronic phase.

Direct EAE models

In direct EAE (models listed above), disease is induced by immunization with spinal cord homogenate or myelin-derived antigens such as MOG, PLP, or MBP proteins or peptides.

Direct EAE is generally the first choice for compound evaluation. These models can be used to test compound efficacy in all disease phases, and are generally shorter (and therefore less expensive) EAE models.

Adoptive transfer EAE

Adoptive transfer EAE is a therapeutic model which isolates the induction phase of EAE from the effector phase. Encephalitogenic helper T cells (CD4+) specific for myelin-derived antigens are generated in donor mice by immunization. These cells are then activated in cell culture and injected into recipient mice, where EAE develops.

This model is robust and more sensitive than other therapeutic EAE models. In addition, adoptive transfer EAE allows study of compounds specifically targeting Th1 or Th17 cells and cell trafficking. Click here for more details.

Treatment regimens

In most EAE models, your study can have any of the following treatment regimens:

Positive controls

Hooke has established the following as positive controls in EAE:

Of these, we use FTY720 (fingolimod, Gilenya) most frequently. It is a very potent inhibitor of EAE development when dosed p.o. at 0.5 mg/kg or more QD. Methylprednisolone and dexamethasone are used often as well.

Copaxone (Teva Pharmaceuticals) is used in MOG35-55/CFA-induced EAE, or in the adoptive transfer EAE model in SJL mice, usually to evaluate efficacy of generic glatiramer acetate.

The best positive control depends on the particular EAE model and the details of your study. Our scientists can help you choose the best model, treatment regimen, and controls to evaluate your compounds.

In vivo readouts

Our usual in vivo readouts for EAE are paralysis score and change in body weight.

Typically, paralysis is scored on a scale of 0 to 5. The scoring method differs slightly depending on the stage of disease (onset/peak vs. recovery). Reliable EAE scoring requires skill which comes after considerable experience. To avoid unconscious bias in scoring, all scoring at Hooke is performed blind, by a person unaware of both treatment and of previous scores for each animal.

Hooke has standardized scoring guidelines for mice and for rats (click for details).

Reporting results

Once or more weekly during your study, we report interim results with raw daily EAE scores and graphs of average EAE scores for each group.

At the end of the study, we perform statistical analysis and issue a final report, normally within 4 weeks of study completion.

Tissue collection and end-of-study analyses

References

[1] Rangacharia, M and Kuchroo V., J Autoimmun 45:31 (2013)
[2] Thakker P et al, J Immunol 187:1986 (2011)
[3] Thakker P et al, J Immunol 178:2589 (2007)
[4] Marusic S et al, J Exp Med 202:841 (2005)
[5] Lyons JA et al, Eur J Immunol 29:3432 (1999)
[6] Mendel I et al, Eur J Immunol 25:1951 (1995)
[7] van der Veen RC et al, J Neuroimmunol 21:183 (1989)
[8] McCarron R and McFarlin D, J Immunol 141:1143 (1988)

See also