The antibody ACSA-1 (astrocyte cell surface antigen-1) is specific for an extracellular epitope of the astrocyte specific transmembrane glycoprotein GLAST in the central nervous system (CNS). Besides GLT-1, GLAST is the most abundant glutamate transporter and is predominantly expressed by astrocytes in the developing and neonatal mammalian CNS. Also radial glia, which belong to the astrocyte lineage and play important roles in development, are known to express GLAST. Postnatally, radial glia only persist in a few regions, such as Bermann glia in the cerebellum, Müller glia in the retina, and radial glia in the dentate gyrus of the adult hippocampus.
