Fig. 3.

Schwann cell demyelinating processes in inflammatory demyelination. Schematic longitudinal drawing shows potential routes for macrophage invasion (red arrows). a Longitudinal extension of myelin uncompaction with intraperiod line separation from an internodal region to the node of Ranvier may disrupt nodal and/or few paranodal junctions, allowing macrophages to invade into the nodal area. b Internodal routes for macrophage invasion into the cytoplasm of inflammatory demyelinating Schwann cell (iDSC). The locus where degenerating myelinosome or the myelin sheath exposed to basal lamina (with a similar manner to Wallerian demyelination), or degenerated outer mesaxon (OM) may provide an internodal route for macrophage invasion. CM compact myelin, PL paranodal loop, RN the node of Ranvier, MV microvilli, BL basal lamina