Surface Structures of Cultured Type 2 Astrocytes Revealed by Atomic Force Microscopy

Abstract

Abstract The incomplete morphological characterization of type 2 astrocytes is in part responsible for the slow progress of studies on these cells. To examine and characterize type 2 astrocytes morphologically, three-dimensional fine structures of the surfaces of type 2 astrocytes cultured from rat cerebella were studied by a combination of atomic force microscopic and immunocytochemical techniques. Atomic force microscopy (AFM) revealed irregular ridge-like structures that form a meshwork distributed throughout the cell body surfaces and the thick processes. These ridges were found to be of two heights (31 nm and 82 nm). This finding indicates two possible configurations responsible for shaping the meshwork: (1) two structures of different thickness are beneath the cell membrane; and (2) two structures are located at two different depths from the cell membrane. On the other hand, immunocytochemical studies for tubulin and glial fibrillary acidic protein (GFAP) revealed that these cytoskeletal filaments a...