Table 1.

Histology analysis strategy

Method	Purpose	Finding
Confocal analysis of 0.2 mm optical sections (n = 104 cells).	To distinguish MDMs (RFP+) from MiDMs (GFP+).	MDMs and MiDMs can be distinguished by cell volume and primary processes.
SBF-SEM inspection in 0.2 mm sections from 14 lesions, 7 mice at EAE onset.	To detect MDMs and MiDMs in SBF-SEM using cell volume and process criteria.	Using criteria detected in the previous step, it is possible to distinguish MDMs and MiDMs in SBF-SEM images.
SBF-SEM inspection of ultrastructure of MDMs and MiDMs.	To detect ultrastructural characteristics of MDMs and MiDMs.	MDMs and MiDMs show characteristic ultrastructural differences regarding their mitochondria, nuclei, osmiophilic granules and microvilli.
Quantification of relation of MDMs (n = 169) and MiDMs (n = 86) to axoglial units (n = 29 intact axons, 46 demyelinated axons).	To determine relationship of MDMs and MiDMs to axoglial units and characterize presence of myelin debris.	Most (55/75; 73%) axoglial units are contacted in limited fashion by MDMs and MiDMs. If one cell type is present (20/75 cells), it’s nearly always (18/20 segments) MDMs.
Reconstruction of 3D shape of four representative MDMs at axoglial units.	To detect relationship of MDMs with axoglial units at EAE onset.	In all, 49 MDMs interacting with axoglial units in absence of nearby MiDMs, 2-3 MDMs were attached to each (n = 18) axoglial unit. MDMs have close relationship with nodes of Ranvier (7 MDMs /75 axoglial units). 3D reconstructions showed four representative MDMs at axoglial units: show one carrying out active demyelination, three at nodes of Ranvier.