Current advances in multiple sclerosis immunopathology

Abstract

Multiple sclerosis is a demyelinating inflammatory disease that affects the central nervous system. Its etiology is the result of a complex interaction between genetic and environmental factors that trigger a deregulated immune response, with the resulting inflammation and neuronal/axonal degeneration. Neuroinflammation is triggered when peripheral leukocytes migrate to the central nervous system and release cytokines such as interleukins 1 and 6 (IL-1 and 6) and tumor necrosis factor (TNF), which act on dwelling cells. The innate immune system plays an important role in the onset and progression of the disease by identifying molecular patterns associated with pathogens and damage, which modulate effector and regulatory functions of the cells where they are expressed, in order to direct the specific immune response. Th17 cells favor the disruption of the blood-brain barrier, which enables the migration of leukocytes to the central nervous system and the triggering of the inflammatory cascade; the Th1 profile (IL-1, IL-6) collaborates to perpetuate it. B-cell function is to produce antibodies and cytokines (IL-6, IL-12 and TFN). Knowledge on multiple sclerosis pathophysiology will enable the development of new therapeutic options that impact on natural history of the disease and its prognosis.