For complex diseases like multiple sclerosis (MS), animal models are highly important because they allow researchers to systematically study numerous factors which contribute to the disease in ways that are not possible in human patients. Animal models also serve as testing arenas for potential treatments. However, the disease complexity which makes animal models so necessary also means that animal models are only able to reflect some aspects of human MS.
Experimental autoimmune encephalomyelitis (EAE) is the oldest model of demyelinating diseases1, and has led to the discovery of human therapies for MS, but EAE has shortcomings that make it difficult to connect findings from the animal model to the human disease, particularly with respect to drug testing2. To induce EAE, researchers stimulate a T-cell-mediated immune response against myelin, which leads to an inflammatory response in the CNS, and demyelination. Not only is the pathophysiology of EAE potentially very different from MS, but since EAE is an induced model, the data is highly dependent on how the experiment is performed3.
Epstein-Barr virus (EBV) infection has been identified as an environmental factor linked to MS susceptibility, and it is likely that other viruses can contribute as well4,5. Many researchers have used Theiler’s murine encephalomyelitis virus (TMEV) intracerebral injections to cause demyelinating disease in mice. Despite being virally-induced, the pathology of these models is mediated by the immune system, not by direct viral effects. Also, the disease course is similar to that observed in chronic progressive MS, making these viral models valuable for studying MS6.
Recently, transgenic mice have come to the forefront of MS research. Unlike previous animal models, some transgenic mouse models can spontaneously develop demyelinating disease, thereby mimicking a key aspect of MS. Two groups independently generated nearly identical double-transgenic mouse models that express both T-cell and B-cell receptors both recognizing myelin oligodendrocyte glycoprotein (MOG)7-9. About half of these mice spontaneously develop an MS-like disease.
Humanized mouse models have also become powerful MS models in recent years. For example, mice expressing MS-associated versions of human leukocyte antigen (HLA) genes can be used in EAE induction experiments, and results can be translated more directly to MS in humans10.
Cyagen Biosciences is the world leader in custom mouse and rat models for research. We will work with you to create the animal model the is right for your experiments. Through our VectorBuilder platform, we also offer a wide variety of molecular engineering services. You can design and order custom DNA and viral constructs specific to your experimental needs, and we will do the cloning for you.