At 42 years old,Stephanie Goldstein developed occasional blurred and double vision,numbness and 'pins and needles' in her arms and legs (paresthesia),and bladder incontinence.After a month of these symptoms she went to her doctor,who sent her to the neurology specialist.An MRI scan revealed areas of demyelination in the central nervous system (CNS),and Stephanie was diagnosed with the autoimmune disease multiple sclerosis (MS).Which of the following best explains why some people are susceptible to the development of MS?

Question

Quizplus · Accepted Answer

One mechanism for achieving immunological tolerance to self proteins is negative selection in the thymus. Developing T cells bearing T-cell receptors that bind too strongly to self MHC or to self-peptide:self-MHC complexes are signaled to die by apoptosis, which eliminates self-reactive T cells. Self proteins not presented to developing T cells in the thymus, such as proteins sequestered in the central nervous system, would not be scrutinized during negative selection, and self-reactive T cells would result.

At 42 Years Old,Stephanie Goldstein Developed Occasional Blurred and Double