RNA-seq analysis reveals differences in transcript abundance between cultured and sand fly-derived Leishmania infantum promastigotes.

Leishmania infantum is responsible for human and canine leishmaniasis in the Mediterranean basin, where the major vector is Phlebotomus perniciosus. Because isolation of sufficient parasites from the sand fly gut is technically challenging, axenic cultivation of promastigotes is routinely used to obtain material for biochemical and genetic analyses. Here, we report the use of Spliced Leader RNA-seq (SL-seq) to compare transcript abundance in cultured promastigotes and those obtained from the whole midgut of the sand fly 5 days after infection. SL-seq allows for amplification of RNA from the parasite avoiding contamination with RNA from the gut of the insect. The study has been performed by means of a single technical replicate comparing pools of samples obtained from sand fly-derived (sfPro) and axenic culture promastigotes (acPro). Although there was a moderate correlation (R2 = 0.83) in gene expression, 793 genes showed significantly different (≥2-fold, p <0.05) mRNA levels in sand fly-derived promastigotes and in culture, of which 31 were up-regulated ≥8-fold (p < 10-8 in most cases). These included several genes that are typically up-regulated during metacyclogenesis, suggesting that sand fly-derived promastigotes contain a substantial number of metacyclics, and/or that their differentiation status as metacyclics is more advanced in these populations. Infection experiments and studies evaluating the proportion of metacyclic promastigotes in culture and within the sand fly gut, previously reported by us, support the last hypothesis.

Treating leishmaniasis in Amazonia: A review of ethnomedicinal concepts and pharmaco-chemical analysis of traditional treatments to inspire modern phytotherapies.

ETHNOPHARMACOLOGICAL RELEVANCE: Cutaneous and mucocutaneous leishmaniasis are neglected tropical diseases that occur in all intertropical regions of the world. Amazonian populations have developed an abundant knowledge of the disease and its remedies. Therefore, we undertook to review traditional antileishmanial plants in Amazonia and have developed new tools to analyze this somewhat dispersed information. MATERIAL AND METHODS: A literature review of traditional remedies for cutaneous/mucocutaneous leishmaniasis in the Amazon was conducted and the data obtained was used to calculate distribution indexes designed to highlight the most relevant uses in Amazonia. The cultural distribution index represents the distribution rate of a given taxon among different cultural groups and was calculated as the ratio of the number of groups using the taxon to the total number of groups cited. The geographical distribution index allowed us to quantify spatial distribution of a taxon's uses in Amazonia and was calculated geometrically by measuring the average distance between the points where uses have been reported and the barycenter of those points. The general distribution index was defined as an arithmetic combination of the previous two and provides information on both cultural and spatial criteria. RESULTS: 475 use reports, concerning 291 botanical species belonging to 83 families have been gathered depicted from 29 sources. Uses concern 34 cultural groups. While the use of some taxa appears to be Pan-Amazonian, some others are clearly restricted to small geographical regions. Particular attention has been paid to the recipes and beliefs surrounding treatments. Topical application of the remedies dominated the other means of administration and this deserves particular attention as the main treatments against Neotropical leishmaniasis are painful systemic injections. The data set was analyzed using the previously defined distribution indexes and the most relevant taxa were further discussed from a phytochemical and pharmacological point of view. CONCLUSIONS: The Amazonian biodiversity and cultural heritage host a fantastic amount of data whose systematic investigation should allow a better large-scale understanding of the dynamics of traditional therapies and the consequent discovery of therapeutic solutions for neglected diseases. Distribution indices are indeed powerful tools for emphasizing the most relevant treatments against a given disease and should be very useful in the meta-analysis of other regional pharmacopeia. This focus on renowned remedies that have not yet benefitted from extended laboratory studies, could stimulate future research on new treatments of natural origin for leishmaniasis.

Tropical diseases screening in immigrant patients with human immunodeficiency virus infection in Spain.

Latent parasitic infections can reactivate because of immunosuppression. We conducted a prospective observational study of all human immunodeficiency virus (HIV)-infected immigrants who visited the Infectious Diseases Department of the Hospital Universitari Vall d'Hebron, Barcelona, Spain, during June 2010-May 2011. Screening of the most prevalent tropical diseases (intestinal parasitosis, Chagas disease, leishmaniasis, malaria, schistosomiasis, and strongyloidiasis) was performed according to geographic origin. A total of 190 patients were included: 141 (74.2%) from Latin America, 41 (21.6%) from sub-Saharan Africa, and 8 (4.2%) from northern Africa. Overall, 36.8% (70 of 190) of the patients had at least one positive result for any parasitic disease: 5 patients with positive Trypanosoma cruzi serology, 11 patients with positive Schistosoma mansoni serology, 35 patients with positive Strongyloides stercoralis serology, 7 patients with positive Leishmania infantum serology, intestinal parasitosis were detected in 37 patients, malaria was diagnosed in one symptomatic patient. We propose a screening and management strategy of latent parasitic infections in immigrant patients infected with HIV.

Ta'ta', Huayani: perception of leishmaniasis and evaluation of medicinal plants used by the Chayahuita in Peru. Part II.

AIM OF THE STUDY: A knowledge attitude and practice study centred on leishmaniasis and its treatment was performed among the Chayahuita, an Amazonian Peruvian ethnic group living in an endemic area. This study documents traditional Chayahuita plant's use and disease concepts. Also, activity of some medicinal plants used by the Chayahuita is highlighted and discussed. MATERIALS AND METHODS: Ninety-three Chayahuita people were interviewed, following a semi-structured questionnaire focussed on disease knowledge and perception, personal attitude and healing practices. Simultaneously, a collection of plants was performed in different ecotopes, in order to make an extensive inventory of the pharmacopoeia. RESULTS: For the Chayahuita, cutaneous (CL) and muco-cutaneous leishmaniasis (MCL) are considered as diseases of their own, with specific names, aetiologies, mode of transmission. Regarding CL, Chayahuita people consider that the humid characteristic of the skin ulcer is a discriminative fact orienting the diagnostic forTa'ta' (leishmaniasis). Forty-six different species were designated useful against LC and /or MCL (29 species by means of the questionnaire and 27 species when collecting in different ecotopes). Thirty-seven extracts corresponding to 31 species used medicinally were screened in vitro against Leishmania amazonensis axenic amastigotes, assessing their viability by the reduction of tetrazolium salt (MTT). Six species displayed a good activity (10 microg/ml

Susceptibility to human cutaneous leishmaniasis and HLA, Gm, Km markers.

A relationship between markers related to the immune response (HLA system, Gm and Km immunoglobulin allotypes) and susceptibility to cutaneous leishmaniasis was investigated in a population of Hmong refugees who had recently settled in French Guiana. Two approaches were used: 1) case/control comparisons of the marker phenotype distribution to detect possible associations; 2) multiple-case family studies to search for marker-linked genes. When the distribution of HLA-A, B, C, antigens and Gm, Km allotypes was compared between patients and controls, only a significant decrease of HLA-Cw7 antigen among leishmaniasis patients was detected (p = 0.01). No interaction between any two of these markers and the disease was found. On the other hand, neither an HLA, Gm or Km susceptibility gene could be demonstrated in the informative sets of affected siblings. These results are discussed with respect to those reported in other infectious diseases.