Severe subcortical TDP-43 pathology in sporadic frontotemporal lobar degeneration with motor neuron disease

Acta Neuropathol. 2008 Jan;115(1):123-31. doi: 10.1007/s00401-007-0315-5. Epub 2007 Nov 15.

Abstract

Recently, TDP-43, a 43 kDa nuclear TAR DNA-binding protein, was identified as the major disease protein in frontotemporal lobar degeneration with ubiquitinated inclusions (FTLD-U), FTLD-U with motor neuron disease (FTLD-MND), and amyotrophic lateral sclerosis. To date, TDP-43 pathology in sporadic FTLD-MND has been reported only in select central nervous system areas. However, this distribution of lesions is insufficient to explain all clinical signs of FTLD-MND and the extent of TDP-43 pathology, throughout the brain, remains unknown. Therefore, as a pilot study, we performed an immunohistochemical whole brain scan of two cases diagnosed clinically as FTLD-MND and two control subjects. We found evidence of both neuronal and glial TDP-43 pathology in multiple brain areas including the nigro-striatal system, neo- and allocortical brain areas, with varying frequency, morphology, and degree, and nowhere in control tissue. The finding of a distinct cytopathological profile consisting of a cell nucleus devoid of endogenous TDP-43 staining coupled with diffuse/granular cytoplasmic staining ("pre-inclusion") was prominent in a couple of brain areas. These pre-inclusions were not or only weakly ubiquitin-immunoreactive. While the findings of severe involvement of extracortical or extrapyramidal areas are strongly suggestive for FTLD-MND being a TDP-43 multisystem proteinopathy rather than a disease predominantly affecting the cortex and spinal cord, more detailed clinicopathological studies of larger cohorts are needed to fully elucidate the distribution and severity of pathological TDP-43 in this disease.

Publication types

  • Case Reports
  • Research Support, N.I.H., Extramural

MeSH terms

  • Brain / metabolism
  • Brain / pathology*
  • DNA-Binding Proteins / metabolism*
  • Dementia / complications
  • Dementia / metabolism
  • Dementia / pathology*
  • Humans
  • Immunohistochemistry
  • Inclusion Bodies / metabolism
  • Inclusion Bodies / pathology*
  • Male
  • Middle Aged
  • Motor Neuron Disease / complications
  • Motor Neuron Disease / metabolism
  • Motor Neuron Disease / pathology*
  • Neuroglia / metabolism
  • Neuroglia / pathology
  • Neurons / metabolism
  • Neurons / pathology
  • Pilot Projects

Substances

  • DNA-Binding Proteins