A New Transmission Blocking Vaccine for Leishmania Infection

A novel transmission blocking vaccine has been developed that can eliminate or reduce the number of Leishmania chagasi parasites in the gut of the sand fly species, Lutzomyia longipalpis. The vaccine involves the production of antibodies to the sand fly midgut protein, LP1, which is normally expressed in the midgut of the sand fly during a blood meal. This vaccine could potentially block parasite transmission from the sand fly to mammalian hosts and significantly reduce the incidence of leishmaniasis in endemic areas of the world such as Brazil, India, and Indonesia where leishmaniasis accounts for over 58,000 deaths annually.

Studies have shown that LP1 antibodies produced by immunized mice are able to reduce the number of L. chagasi parasites that develop in the midgut of Lu. longipalpis. These results illustrate the potential use of the protein as a vaccine to immunize dogs and protect humans from visceral leishmaniasis transmitted by the sand flies that feed on the infected, vaccinated dogs. In endemic areas such as Brazil where dogs are the principal reservoir for L. chagasi, the LPl antigen alone or in combination with other sand fly midgut proteins could be used to immunize household pets and stray dogs. Vaccinated dogs will produce antibodies to LPl, and once a sand fly feeds on blood from the infected and vaccinated dogs, the antibodies will inhibit development of the parasite in the gut of the sand fly. This approach can effectively block Leishmania transmission to human hosts. Such vaccines have the potential to reduce the risk of humans acquiring leishmaniasis without the risks involved in human vaccination. CRADA Opportunity: The NIAID, OTD is seeking statements of capability or interest from parties interested in collaborative research to further develop, evaluate, or commercialize "A New Transmission Blocking Vaccine for Leishmania Infection". Please contact Dana Hsu at 301-496-2400 for more information.

Source: http://www.ott.nih.gov/Technologies/abstractDetails.aspx?RefNo=2086

Giulianna Ramirez Grace Park Gretha Cavazzoni Gwen Stefani Halle Berry