Detection of epidermal growth factor receptors and E-cadherins in the basolateral membrane of A431 cells by laser scanning fluorescence microscopy.

We have examined the localization of epidermal growth factor (EGF) receptors and E-cadherins in cultured A431 cells, an epidermoid carcinoma cell line, using a laser scanning fluorescence microscope. The fluorescence signals generated by monoclonal antibodies against EGF receptor and E-cadherin were localized mainly in the cell-cell contact sites, about 3 microns in width. When these areas for cell adhesion were scanned perpendicularly, fluorescence was detected from a point 4 microns from the cell base for a distance of 8 microns towards the cell surface (about 16 microns from the cell base). These data suggest the subcellular localization of EGF receptors and E-cadherins in the basolateral membrane of A431 cells.