[Characterization of lectin receptors on cell surfaces with regard to functional aspects].

The actual definitions of lectins are presented and discussed and lectins are classified as one group of the affinitins. The ability of lectins to bind carbohydrates serves as a widely used principle in the nature for cell recognition and adhesion processes. By means of labelled glycoconjugates the identification, localization and quantitation of receptor bound lectins can be investigated as by lectinological as by a combination of lectinological and immunological reactions. The special properties of toxic lectins are discussed by use of the lectin I from mistletoe as characteristic example. The coupling of A-chains with antibodies (immunotoxins) or other haptomers (affinotoxins) leads to agents render it possible to influence directly cell functions.