GFAP [GA-5]

Glial fibrillary acidic protein (GFAP) is the subunit of the glial specific “intermediate” filament that include desmin filaments in smooth muscle, vimentin filaments in cultured fibroblasts, keratin filaments in epithelium and neurofilaments in neural cells. GFAP is a major product of astrocytic differentiation. Compared with special stains currently used to identify an astroglial component in brain tumors, GFAP staining is more sensitive. Further, the immunohistochemical staining method is useful in demonstrating reactive astrocytes, whether secondary to a brain tumor or to any other neuro-pathological condition.