Niosomes as a novel peroral vaccine delivery system.

The feasibility to develop a peroral vaccine delivery system based on non-ionic surfactant vesicles (niosomes) was evaluated using BALB/c mice. Ovalbumin was encapsulated in various lyophilized niosome preparations consisting of sucrose esters, cholesterol and dicetyl phosphate. Two different formulations were compared in this study. The specific antibody titres within serum, saliva and intestinal washings were monitored by ELISA on days 7, 14, 21 and 28 after intragastric administration. Only encapsulation of ovalbumin into Wasag7 (70% stearate sucrose ester, 30% palmitate sucrose ester (40% mono-, 60% di/tri-ester)) niosomes resulted in a significant increase in antibody titres. Administration of ovalbumin and empty niosomes did not exert a similar effect, neither did administration of any control formulation. In contrast to ovalbumin loaded Wasag7 niosomes, application of the more hydrophilic Wasag15 (30% stearate sucrose ester, 70% palmitate sucrose ester (70% mono-, 30% di/tri-ester)) niosome preparations did not result in an increase in antibody titres.