Delivery of immunogens to mucosal immune system using an oral inactivated cholera vaccine: a new approach for development of oral vaccines.

Oral vaccines have several attractive features; however, due to several challenges, to date, only a limited number of oral vaccines are licensed. Over the past two decades, several oral vehicle delivery systems have been developed to address these challenges and deliver antigens to the target cells in the mucosal immune system. While the size of vehicle delivery systems, the quantity of components in the vehicle formulation, the dose of administration, and even the type of animals species, are important aspects in development of a suitable oral vaccine, our results showed that entrapment of inactivated Vibrio cholera, a component in the structure of Dukoral vaccine into oral vehicle delivery systems, is able to induce a more rigorous humoral immune response in the systemic compartment. We further investigated the mechanism of Dukoral vaccine as a potential stimulator in induction of immune response by immunizing TLR-2-, TLR-4-, MyD88- and Trif-deficient mice. We are hopeful that these findings will lead to development of more precisely-designed oral vaccines in the future.