Background:
Multiple sclerosis is a chronic inflammatory disease that affects the CNS (brain and spinal cord). MS attacks the myelinated axons in the CNS, causing adverse effects in motor and autonomic function. The four major categories of MS are relapsing-remitting MS, secondary progressive MS, primary progressive MS, and progressive-relapsing MS but the course of the disease remains very unpredictable. Although tests to diagnose MS do not exist, studies have shown that genetic and environmental factors may have a substantial effect in the incidence of MS. For example, the incidence rate of MS is twice as high for women compared to men and significantly higher in people with a Northern European. Recent studies have shown different factors, such as viruses and bacteria, to trigger MS as well. …show more content…
External agents seem to be of interest in the deregulation of T cell selection, known as negative selection, in the thymus. The incorrect mechanism for screening certain subsets of human cells causes differentiation of auto reactive and self-antigen specific cells to enter the periphery. The self-antigen specific T cells usually recognize myelin antigens located in the CNS such as MOG, PLP, and MBP. These activated cells, through an unknown mechanism, diffuse through the blood brain barrier (BBB) and attack myelin components located in the CNS, causing lesions in the brain and spinal