Identification of Glial Fibrillary Acidic Protein by the Immunoperoxidase Method in Human Brain Tumors

The immunocytochemical localization of glial fibrillary acidic portein within glioma cell bodies and their processes by the immunoperoxidase method is demonstrated to be of diagnostic value. This method has advantages over "special" stains because it is not so dependent upon color alone, and because it identifies a specific protein in the cells. The immunoperoxidase method using antiserum to glial fibrillary acidic protein is shown to be useful for the differentiation of mixed glial and mesenchymal tumors, and for the diagnosis of tumors in which a glial or mesenchymal cell origin is in doubt.