Autoimmune T-Cell Reactivity to Myelin Proteolipids and Glycolipids in Multiple Sclerosis
Figure 1
Stylized diagram of myelinated nerve fibres in the CNS. (a) Myelin is produced by the oligodendrocyte (OLIG) and is laid down in segments along nerve axons. Single oligodendrocytes can myelinate up to 50 segments. The area of bare axon between each myelinated segment (shown in yellow) is called the node of Ranvier. Electrical impulses move down the axon by “jumping” from one node to another in a process known as saltatory conduction. A cross-section through the myelinated segment at the dotted line is shown in (b). (b) The myelin sheath forms from flattened cytoplasmic processes from the oligodendrocyte that are elaborated around the axon and which then compact their cytoplasmic content (except for small pockets at the periphery of the membrane, which can appear as the inner loop (IL) immediately adjacent to the axon and the outer loop (OL) at the outer edge of the membrane). The major dense line represents the compacted cytoplasm. The intraperiod line is formed by close apposition of the membrane layers.
