Vaccine as immunotherapy for leishmaniasis

Abstract Visceral leishmaniasis (VL) is a tropical and subtropical disease that is endemic in more than 80 countries around the world. A large number of leishmaniasis vaccine candidates are in various stages of development with preclinical and clinical trials ongoing. Several vaccine candidates are composed of an individual parasite antigen or a combination of antigens produced as a multiepitope vaccine. The efficacy of a vaccine can be improved by combining with some adjuvants, that promote a protective immune response, inducing long-term immunity. The discovery of Toll-like receptors (TLRs) has provided many information on the immunostimulatory effect of several bacterial components that can be connected to TLRs, improving the adaptive immune responses for vaccine formulations. New agonists of TLRs have been discovered and used to test new vaccine formulation showing good efficacy. This chapter aims to discuss the new vaccine candidates for leishmaniasis and the importance of the adjuvants used in the vaccine formulation.