Abstract
Sand flies transmit parasites of genus Leishmania, the causative agents of leishmaniases. Experimental hosts repeatedly exposed to sand fly saliva can control Leishmania infection.
Cell-mediated anti-saliva immune response is most likely responsible for this protective effect; however, there is no study concerning its antigenic specificity. In this study, splenocytes from mice exposed to Phlebotomus sergenti bites were challenged ex vivo with saliva from three different sand flies.
Mice bitten by P. sergenti had higher proliferation to homologous antigen than splenocytes from naive mice. Splenocytes from P. sergenti bitten mice as well as anti-P. sergenti antibodies partially cross-reacted with P. papatasi saliva.
In contrast, no crossreactivity was found with P. arabicus saliva. Our data indicate that both cellular and humoral immunity react in a species-specific manner and the unique transmission-blocking vaccine would be required for each vector – Leishmania combination.