Walter has a degenerative condition known as multiple sclerosis (ms). in the context of specialized cell structure, his disease is most likely caused by the:

The disease is caused mainly because of the attack on the myelin sheath by own immune system.

Explanation:

The MS or multiple sclerosis refers to a possibly disabling disorder of central nervous system. In the condition, immune system fights against and destroys the myelin, that is, the protective sheath, which envelopes the nerve fibers. This causes problems of communications between the brain and the entire part of the body. Ultimately, the disease can result in deterioration or permanent destruction of the nerves.

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