Sand fly saliva plays an important role in Leishmania transmission. We characterized the host antibody response to saliva from 3 sand fly species. Specific IgG was observed in sera from experimentally bitten mice as well as in sera from individuals living in the endemic area of Leishmania tropica in Sanliurfa, Turkey. Sera of Sanliurfa inhabitants showed high IgG levels against saliva of Phlebotomus sergenti and P. papatasi, the 2 most abundant sand fly species in this area, but did not react with saliva of the New World sand fly, Lutzomyia longipalpis. Patients with active Le. tropica lesions possessed significantly higher anti-P. sergenti IgG levels than the healthy individuals from the same place while anti-P. papatasi IgG levels were equal in both groups. Major protein bands in P. papatasi and P. sergenti saliva reacted with both, human and mice sera; in P. papatasi, however, mouse IgG recognized preferentially the 42 kDa protein band while the human IgG reacted strongly with the 30 kDa band. Our data suggest that the antibody response to sand fly saliva could be used for monitoring the exposure of humans and other hosts to sand flies and might be used as a marker of risks for Leishmania transmission in endemic areas.

No abstract

Infantile Mediterranean visceral leishmaniasis (IVL) and anthroponotic cutaneous leishmaniasis (ACL) have long been known to exist in the western and southeastern Turkey, respectively. To further study these and other related diseases, a recombinant antigen (rK39) specific to VL was used in an ELISA for serodiagnosis of selected patients and for screening dog reservoir populations in several endemic sites. Among 24 confirmed VL cases from western Turkey, the rK39 ELISA proved to be more sensitive than a combination of cultivation and microscopy of bone marrow aspirates. The specificity of rK39 for leishmaniasis was demonstrated by its lack of cross-reactivity with sera from other human diseases in the same sites. Interestingly, six of the 83 parasitologically proven ACL cases from southeast Turkey were also rK39 positive. The end point titers of the positive VL and CL cases vary from 10 Ϫ2 to 10 Ϫ5 and from 10 Ϫ2 to 10 Ϫ3 , respectively. The rK39 ELISA was also used to screen 494 apparently healthy dogs from Urfa in southeast Turkey, Manisa/Alasehir near the Aegean Sea, and Karabuk near the Black Sea. Eighteen rK39-positive cases (3.6%), all from the latter two areas, were found to have varying endpoint titers (10 Ϫ2-10 Ϫ4). The high titers predicted increased severity and frequency of the clinical symptoms (i.e., lymphadenopathy, depilation, skin lesion, weight loss and/or death), which were manifested subsequently in 16 of these 18 cases. In addition, more positive canine cases were diagnosed by the rK39 ELISA preclinically than the procedures to detect parasites postsymptomatically in the lymph node aspirates. The use of the rK39 ELISA as a sensitive tool makes it possible to demonstrate coendemicity of canine and human VL, as expected in the case of IVL. The results also point to the possible presence of additional VL types in western Turkey and cutanovisceral type in the southeast part of this country.

Leishmania isolates from 57 cases of human cutaneous (CL), human visceral (VL), and canine visceral (CVL) leishmaniasis in Turkey were grouped by multi-site DNA polymorphism analyses into five genotypes. The initial grouping was based on DNA heterogeneity of the faster-evolving mitochondrion (kinetoplast) minicircles and the intergenic regions of two nuclear repetitive genes. Taxonomic affiliation and phylogenetic relationships of the five genotypes were inferred by comparing them with reference species for sequence heterogeneity in a approximately 1.4 kb conserved single-copy gene, encoding N-acetylglucosamine-1-phosphate transferase (NAGT). Alignment of the available sequences revealed no gap, but up to 7% scattered base substitutions, suggesting that this functionally important gene is a suitable marker. Three genotypes are completely identical to the NAGTs of the reference species, identifying them as L. infantum, L. tropica. and L. major, respectively. The remaining two are recognized as L. major NAGT variants with one and four base substitutions, respectively. As expected, Maximum Likelihood analysis of the NAGT sequences separates them into three clades, corresponding to the three species. The majority of the isolates obtained are L. infantum and L. tropica, which have been known to cause infantile VL and anthroponotic CL in western and southeastern Turkey, respectively. Unexpected is the finding of Leishmania major variants and their dispersal, possibly as previously unrecognized clinico-epidemiologic entities of CL and VL.

No abstract

No abstract

No abstract

No abstract