Table 2.

Characteristics of cerebral adrenoleukodystrophy lesions

	Normal-appearing white matter	Prelesional zone	Actively demyelinating zone	Gliotic core
Myelin	Normal.	No relevant myelin loss, myelin vacuolization.	Significant myelin breakdown. Few residual myelinated axons.	(Almost entirely) absent. Remnants vacuolized.
Axons	Normal.	Normal morphology, but immunohistochemical signs of damage1.	Substantial loss of axons.	(Almost entirely) absent.
Astrocytes	Normal.	Occasional reactive cells.	Numerous reactive cells, pattern of anisomorphic gliosis.	Scattered reactive astrocytes, pattern of isomorphic gliosis.
Oligodendrocytes	Normal.	Mild oligodendrocyte loss, cells have condensed nuclei.	Significant oligodendrocyte loss.	(Almost) entirely absent, altered morphology with few or no processes.
Microglia	Higher numbers with initial reactive morphology. Expression of homeostatic markers.	Almost entirely absent.	Significant microgliosis.	Return to near-normal activation state, with expression of homeostatic markers.
Macrophages	Absent.	Sparse macrophages, mainly in perivascular spaces.	Drastic increase in lipid-laden foamy macrophages containing degraded myelin fragments.	Persisting slight increase in numbers, as compared to NAWM.
Lymphocytes	Absent.	Absent.	Prominent perivascular cuffings of T-lymphocytes. Sparse B-lymphocytes and plasma cells.	Rare T-lymphocytes.

¹ Axonal damage was assessed by staining for amyloid precursor protein (APP) and Bielschowsky silver impregnation. The presented results were extracted from studies by Schaumburg et al. (1974 and 1975), Powers et al. (2000), Ito et al. (2001), Eichler et al. (2008) and Bergner et al. (2019 and 2021)