Recent advances in vaccines for leishmaniasis.

The observation that recovery from infection with Leishmania confers immunity to reinfection suggests that control of leishmaniasis by vaccination may be possible. However, there are no vaccines available at present to control any form of leishmaniasis, despite considerable efforts. Studies of the immunopathogenesis and mechanisms of protective immunity, mainly derived from animal models of experimental leishmaniasis, have defined a number of features that should be met by an effective vaccine. In addition, several antigens have been identified that may be potential vaccine candidates, and molecular biological techniques have made them available as recombinant proteins for second-generation vaccines. Furthermore, molecules present in the saliva of Leishmania-transmitting vectors have been demonstrated as valuable candidates for the development of anti-Leishmania vaccines. This review concentrates on the most promising vaccine candidates and highlights new approaches for the development of vaccines. Finally, based on present knowledge, the future prospects for developing an effective vaccine against the different clinical forms of leishmaniasis are discussed.