Current progress in the development of the B subunits of cholera toxin and Escherichia coli heat-labile enterotoxin as carriers for the oral delivery of heterologous antigens and epitopes.

The development of non-living carrier systems for delivery of protective antigens or epitopes to the immune system represents both a fundamental and an applied aspect of vaccinology. A wide range of carrier systems, ranging from inert supports to proteins that exert direct immunomodulating effects on the immune response, are being studied. In this overview we describe the current progress in the development of the B-subunits of cholera toxin and Escherichia coli heat-labile enterotoxin as potential protein carriers for the oral delivery of chemically and genetically attached antigens and epitopes.