Molecular basis of lectin-carbohydrate interactions

Studies carried out during the last two decades, many of them with the aid of lectins, have firmly established that all cells come in a sugar coating, and that this coating usually changes in the course of normal processes of growth and development, as well as in pathological situations. Concurrently, it has been found that many cells express surface lectins, which may function as recognition molecules by combining with sugars on the surfaces of apposing cells (Sharon and Lis, 1989a, 1989b) (Table I). A recent example, which has created a great deal of excitement, is the identification of the cell adhesion molecules, named select ins or LEC-CAMs, that mediate adhesion of leukocytes to carbohydrates on endothelium and platelets during inflammation and blood clotting (Brandley et al., 1990; Laskey, 1991; McEver, 1991; Rosen, 1990; Springer and Laskey, 1991).