Lectin-mediated drug delivery: Fundamentals and perspectives

Apart from the genetic and the peptide code, the sugar code appears more and more as a possible mailing system for biological information, Relying on carbohydrate-protein interactions, lectin-mediated drug delivery is a promising strategy to improve the efficacy of poorly absorbable drugs by opening endocytic pathways. This contribution summarizes the fundamentals of lectin-mediated drug delivery by describing the fate of lectins, especially that of wheat germ agglutinin, at the cellular level. Additionally, some issues probably limiting this strategy are discussed. In an effort to a practical application of the concept, perspectives for utility of lectins for oral, gastrointestinal and pulmonary drug delivery including prodrugs, microspheres, liposomes, and nanospheres are described. The challenge for the future will be to overcome some real or fictive hurdles now limiting the transformation of the concept into clinical practice. Nevertheless, lectin-mediated drug delivery technology offers new beneficial and exciting perspectives even for administration of proteinaceous drugs, vaccines, and therapeutic DNA.