Nanocarriers for Transmucosal Vaccine Delivery

Immunization has been realized as one of the most cost effective methods of controlling microbial infections. Currently, the most widely employed means of vaccine delivery includes intramuscular injection which is effective against pathogens invading via the systemic route. The antibody titers do not extend to mucosal or serosal sites which are also the portals of entry for invading pathogens. Mucosal means of delivery comes as viable alternatives. The oral route for mucosal vaccination has not been successful in presenting antigens to the body. Acidic environment and inactivating enzymes of the GI tract degrade the antigen before it is presented to the M-cells of Peyer's patches. Nanocarrier based vaccines however, can help to overcome the problems associated with mucosal delivery. These carriers have shown to improve the bioavailability, act as adjuvant to provoke a stronger immune response while being targeted to associated tissues, leading to improved success of vaccination which inculcates interest of nanotechnology in vaccination. This review encompasses a wide range of nanocarriers that have been of interest.