Ubiquitin-positive tau-negative intraneuronal inclusions in dementia with motor neuron disease

The 50th Anniversary of Japanese Society of Neuropathology


Koichi Okamoto, MD, PhD, Department of Neurology, Gunma University Graduate School of Medicine, 3-39-22, Showa-machi, Maebashi 371-8511, Japan. Email: okamotok@med.gunma-u.ac.jp


We first reported ubiquitin-positive tau-negative intraneuronal inclusions in the hippocampal granular cell layer and entorhinal cortices in patients with amyotrophic lateral sclerosis (ALS). We then found that those inclusions occur frequently in patients with presenile dementia and motor neuron disease. The ultrastructure of the inclusions consists mainly of granules with a few filaments. In 2006, TDP-43 was identified as a major component of the inclusions specific for frontotemporal lobar degeneration and ALS. Here, we review the current knowledge regarding ubiquitin-positive tau-negative intraneuronal inclusions.