Novel approaches for oral delivery of macromolecules.

Traditional forms of administrations of nonabsorbable drugs and peptides often rely on their parenteral injection, since the intestinal epithelium is poorly permeable to these therapeutical agents. A number of innovative drug delivery approaches have been recently developed, including the drug entrapment within small vesicles or their passage through the intestinal paracellular pathway. Zonula occludens toxin, a recently discovered protein elaborated by Vibrio cholerae, provided tools to gain more insights on the pathophysiology of the regulation of intestinal permeability through the paracellular pathway and to develop alternative approaches for the oral delivery of drugs and macromolecules normally not absorbed through the intestine.