Visualization of Concanavalin A-binding Sites with Scanning Electron Microscopy

Plant lectins, because they bind to specific carbohydrate moieties, can be used to investigate the glyco-components of the cell surface. When considering the distribution, number, or mobility of lectin-binding sites, a distinction must be made between a natural distribution and a redistribution induced by binding with multivalent ligands (2, 4, 5, 8, 14, 15). In some cell types the induced redistribution results in the phenomenon of "cap-ping." Taylor et al. (14), on the basis of immuno-fluorescent studies, introduced the term capping to refer to the progressive movement and clumping of receptor-ligand complexes (e.g. binding site-lectin complexes) to form an aggregate of these com