Ubiquitin-positive inclusions in different types of multiple system atrophy: distribution and specificity

Multiple system atrophy (MSA) is a neurodegenerative disorder that encompasses different clinicopathological syndromes, either occurring alone or with a variable degree of overlap. Oligodendroglial, intracytoplasmic argyrophilic and ubiquitin-reactive inclusions are regarded as a histologic hallmark. We examined the distribution and specificity of these ubiquitin-reactive inclusions (UBRI) in 20 cases of MSA (7 cases of sporadic adult olivoponto-cerebellar atrophy [OPCA], 1 case of hereditary adult OPCA, 4 cases of infantile OPCA, 2 cases of Shy-Drager-Syndrome [SDS], 4 cases of striatonigral degeneration [SND] and 2 cases of non-classified atrophy of multiple systems) and 93 control cases with various disorders. Antibodies were used against ubiquitin, PGP 9.5, TAU-protein, glutathion-S-transferase (GST) and metallothionein (MT). Oligodendroglial UBRI were detected in all but 2 cases of sporadic adult MSA and 3 controls, whereas they were absent in hereditary and infantile OPCA. They could also be recognized with Gallyas stain and anti-TAU. Immunopositivity was also seen with GST (11 cases), PGP 9.5 (4 cases) and MT (1 case). Distribution of oligodendroglial UBRI, although not showing topographical linkage to neuronal degeneration in all cases, does not seem to occur in a haphazard pattern.