Monoclonal antibodies to glial fibrillary acidic protein. 1. Characterization.

Mouse hybridomas producing antibodies to glial fibrillary acidic protein (GFAP) have been cloned and their immunoglobulins characterized biochemically, immunochemically and immunocytochemically. Immunoaffinity columns were prepared using cyanogen bromide activated sepharose 4R and the antibodies of the C9 clone. A protein giving a single band in the 50-55 kd range was thus isolated from aqueous extracts of bovine brain. The clone yields antibodies which are, on the basis of these studies, specific for GFAP. The antibody belongs to the class IgG1 and has been applied to human tissues, both frozen sections and sections embedded in paraffin wax following fixation in formaldehyde. The results show that the antibody may be of assistance in the classification of human brain tumors.