Multiple Sclerosis: Immune Cells, Histopathology, and Therapeutics

Abstract

Multiple sclerosis (MS) is an inflammatory demyelinating disease affecting the central nervous system (CNS). In MS, oligodendrocytes and myelin that surround axons to facilitate transmission of neuronal signals are destroyed by adaptive and innate immune cells, resulting in the formation of demyelinating plaques. For many years, research into MS pathophysiology has identified immune cell populations in lesions such as T cells, B cells, and myeloid and innate lymphoid cells. In this review, we discuss the involvement of these immune cells in MS pathophysiology and demonstrate how findings from histopathology studies and single-cell analyses in animal and human models have identified which immune cell subsets contribute to disease. This knowledge has facilitated the introduction of numerous immune-targeted therapeutics towards CD20, CD52, interferon-beta, sphingosine-1-phosphate receptor, Bruton’s tyrosine kinase, and many more. These treatments have shown effective reduction in new lesion formation and management of symptoms in MS patients. Furthermore, as MS is a chronic disease, these therapeutics slow disease progression, reduce cognitive disabilities, and prevent relapses. Further research is required to develop a cure for MS with limited side effects. The ongoing research that utilises innovative methods to identify and assess MS pathophysiology could transform the treatment landscape for patients in the future.