A variety of glial pathological structures by the modified Gallyas‐Braak method

Abstract

Recent knowledge on tau‐positive glial abnormal structures and their clinico‐pathological significance were introduced. The structures outlined here, which are strikingly visualized by the modified Gallyas‐Braak method and have tauepitopes, included (i) tuft‐shaped astrocytes, (ii) thorn‐shaped astrocytes, (iii) glial coiled bodies, (iv) argyrophilic threads, (v) firework‐like structures and (vi) argyrophilic perivascular astrocytic feet. This study concludes that the tuft‐shaped astrocytes are favored in cases of progressive supranuclear palsy (PSP), and that there is a massive appearance of both the argyrophilic threads and the firework‐like structures characteristic in prototype of corticobasal degeneration (CBD). Unlike these structures, glial coiled bodies were observed in a wider range of neurological diseases such as PSP, CBD and some other cases with precocious appearance of the neurofibrillary tangles, although the glial coiled bodies were rare in routine laboratory examination and were not always uniform in their configuration. Thus, the modified Gallyas‐Braak method is useful for the diagnosing of some neurodegenerative diseases with tau abnormalities, especially of PSP and CBD. It must be noted, however, that this method could also impregnate tau‐negative structures such as glial cytoplasmic inclusions (oligodendroglial microtubular tangles) in multiple system atrophy or grumose or foamy spheroid body in various conditions, especially in PSP and CBD.