Early and progressive accumulation of reactive microglia in the Huntington disease brain

E Sapp, KB Kegel, N Aronin… - … of Neuropathology & …, 2001 - academic.oup.com
E Sapp, KB Kegel, N Aronin, T Hashikawa, Y Uchiyama, K Tohyama, PG Bhide, JP Vonsattel…
Journal of Neuropathology & Experimental Neurology, 2001academic.oup.com
Microglia may contribute to cell death in neurodegenerative diseases. We studied the
activation of microglia in affected regions of Huntington disease (HD) brain by localizing
thymosin β-4 (Tβ4), which is increased in reactive microglia. Activated microglia appeared in
the neostriatum, cortex, and globus pallidus and the adjoining white matter of the HD brain,
but not in control brain. In the striatum and cortex, reactive microglia occurred in all grades of
pathology, accumulated with increasing grade, and grew in density in relation to degree of …
Abstract
Microglia may contribute to cell death in neurodegenerative diseases. We studied the activation of microglia in affected regions of Huntington disease (HD) brain by localizing thymosin β-4 (Tβ4), which is increased in reactive microglia. Activated microglia appeared in the neostriatum, cortex, and globus pallidus and the adjoining white matter of the HD brain, but not in control brain. In the striatum and cortex, reactive microglia occurred in all grades of pathology, accumulated with increasing grade, and grew in density in relation to degree of neuronal loss. The predominant morphology of activated microglia differed in the striatum and cortex. Processes of reactive microglia were conspicuous in low-grade HD, suggesting an early microglia response to changes in neuropil and axons and in the grade 2 and grade 3 cortex, were aligned with the apical dendrites of pyramidal neurons. Some reactive microglia contacted pyramidal neurons with huntingtin-positive nuclear inclusions. The early and proximate association of activated microglia with degenerating neurons in the HD brain implicates a role for activated microglia in HD pathogenesis.
Oxford University Press