A basic overview of multiple sclerosis immunopathology

<jats:p>Multiple sclerosis (<jats:styled-content style="fixed-case">MS</jats:styled-content>) is a multi‐component disease characterized by inflammation, neurodegeneration and failure of central nervous system (<jats:styled-content style="fixed-case">CNS</jats:styled-content>) repair mechanisms. Immune dysregulation appears to originate with dendritic cells (antigen‐presenting cells) which have an activated phenotype in individuals with <jats:styled-content style="fixed-case">MS</jats:styled-content>. Dendritic cells migrate across the blood–brain barrier and induce differentiation of memory T cells into pro‐inflammatory T helper 1 (Th1) and Th17 lymphocytes. In turn, induction of macrophage and microglial activation produces other pro‐inflammatory cytokines and oxygen and nitric oxide radicals responsible for the demyelination and axonal loss. Other known mediators of <jats:styled-content style="fixed-case">MS</jats:styled-content> pathology include <jats:styled-content style="fixed-case">CD</jats:styled-content>8+ T cells and memory B cells within the <jats:styled-content style="fixed-case">CNS</jats:styled-content>. Some pathological hallmarks of <jats:styled-content style="fixed-case">MS</jats:styled-content> are early axonal degeneration and progressive decline of brain volume in patients with clinically isolated syndromes who progress to clinically definite <jats:styled-content style="fixed-case">MS</jats:styled-content>. Many new options to interfere with the course of <jats:styled-content style="fixed-case">MS</jats:styled-content> have become available in recent years. To limit inflammatory demyelinating processes and delay disease progression, intervention to control inflammation must begin as early as possible. Each distinct type of immunotherapy (immunomodulation, immunosuppression and immune‐selective intervention – blockade type, sequestering type or depleting type) corresponds to a specific underlying immunopathology of <jats:styled-content style="fixed-case">MS</jats:styled-content>.</jats:p>