Immunofluorescent staining of frozen sections for glial fibrillary acidic protein.

Immunofluorescent staining for glial fibrillary acidic protein (GFAP) has been used as part of the diagnostic evaluation of eleven patients and compared with routine special stains. In one case, a difficult fibrillary neoplasm of the spinal cord, this diagnostic procedure provided rapid, positive identification of the glial nature of the tumor. In all cases, the GFAP reactivity was consistent with staining properties of PTAH and more rapid than PTAH.