Figure 4.

Clinical aspects of multiple sclerosis. (a) For quantification of the degree of disability, for example in the clinical assessment of new treatments, the expanded disability status scale (EDSS) has been developed (Kurtzke, 1983). (b) A graphical representation of the most common MS phenotype. In the beginning MS is asymptomatic, but with advanced imaging techniques (contrast-enhanced MRI for example) focal abnormalities due to inflammation can be observed inside the brain white matter. This is followed by a period of variable length between patients where the inflammation increases in severity causing discrete episodes of disability (relapse) alternating with complete recovery (remission). In about 50 % of the patients with relapsing–remitting MS the disease becomes progressive, where remissions disappear and neurological functions decrease progressively. Based on data from the marmoset EAE model, we posit that the degeneration of oligodendrocyte/myelin complexes can be differentiated into three types: (1) normal age-appropriate progressive degeneration; (2) progressive degeneration amplified by a newly discovered T cell attack on oligodendrocytes; (3) reversible degeneration induced by a classical autoimmune attack of pro-inflammatory T cells and autoantibodies on myelin sheaths.