Green fluorescent protein-tagged Leishmania in phlebotomine sand flies

In this work we have used for the first time green fluorescent protein (GFP ) tagged cells of the human parasite Leishmania donovani to observe its dev elopment in the gut of phlebotomine sand flies. Low numbers of GFP-tagged L . donovani were more easily detected than nontagged Leishmania, suggesting that GFP-tagged Leishmania could be used to efficiently study the biology o f Leishmania in their vectors, and open the possibility of using nonaxenic flies. Using this method, we found that GFP-tagged L, donovani, the ethiolo gical agent of Old World Kala-azar, were able to establish an infection wit hin the gut of Lutzomyia species, which are vectors of New World Leishmania . The GFP-tagged parasites divide successfully in the gut of colonized and in wild caught Lu. longipalpis (Lutz & Neiva, 1912), Lu. ovallesis (Ortiz, 1952), and Lu. youngi (Feliciangeli & Murillo, 1985). In the case of Lulong ipalpis the labeled parasite exhibited a normal anterior development as the one observed in its natural vector.