Demyelination of which cell type's myelin sheaths is the underlying pathology in multiple sclerosis, a disease of autoimmune origin?

Oligodendrocytes produce and maintain myelin in the central nervous system, and their autoimmune-mediated destruction is the central pathology of multiple sclerosis. Schwann cells perform the analogous function in the peripheral nervous system (relevant to conditions like Guillain-Barré syndrome instead).