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Objective: There exist various diagnostic tests to detect visceral leishmaniasis, but the most efficient ones have not been demonstrated yet. Herein, we evaluated the accuracy of these diagnostic tests in Iran. Methodology: English and Persian database searching was done from 1993 to 2016. According to heterogeneity of the studies, estimations of the study were pooled by random-effects model. Totally, twenty investigations were eligible for current review with 2115 patients as pooled sample size. Results: The overall pooled estimate of sensitivity and specificity for all diagnostic tests were 0.92 ([95% CI = 0.90-0.95]) and 0.92 ([95% CI = 0.89-0.94]), respectively. Also, the separate sensitivity and specificity of each test were as follow: PCR: 1.00 ([95% CI = 0.99-1.01]) and 0.37 ([95% CI = 0.25-0.49]); DAT: 0.93 ([95% CI = 0.89-0.96]) and 0.92 ([95% CI = 0.89-0.94]); ELISA: 0.78 ([95% CI = 0.47-1.09]) and 1.00 ([95% CI = 0.99-1.01]) as well as IFA: 0.50 ([95% CI = 0.29-0.72]) and 0.96 ([95% CI = 0.95-0.97]). Conclusions: The specificity and sensitivity of PCR and DAT as molecular and serological tests, respectively, are remarkable to detect visceral leishmaniasis; hence, it is highly recommended to simultaneously employ these diagnostic tests for this widespread infection. [ABSTRACT FROM AUTHOR]

N -oxide derivatives compounds such as furoxan and benzofuroxan are promising scaffolds for designing of new antileishmanial drugs. A series of furoxan (1,2,5-oxadiazole 2- N -oxide) (compounds 4a-b , and 14a-f ) and benzofuroxan (benzo[c][1,2,5]oxadiazole1- N -oxide) (compounds 8a-c ) derivatives were evaluated against in vitro cultured L. infantum promastigotes and amastigotes. The compounds exhibited activity against promastigote and intracellular amastigote forms with EC 50 values ranging from 2.9 to 71.2 μM and 2.1 to 18.2 μM, respectively. The most promising compound, 14e , showed good antileishmanial activity (EC 50 = 3.1 μM) against intracellular amastigote forms of L. infantum with a selectivity index, based on murine macrophages (SI = 66.4), almost 3-times superior to that presented by the standard drug amphotericin B (AmpB). The efficacy of 14e to eliminate the parasites in vivo was also demonstrated. Treatment of L. infantum -infected hamsters with compound 14e at 3.0 mg/Kg/day led to a meaningful reduction of parasite load in spleen (49.9%) and liver (54.2%), respectively; these data were corroborated by histopathological analysis, which also revealed reduction in the number of inflammatory cells in the liver of the treated animals. Moreover, histological analysis of the spleen and kidney of treated animals did not reveal alterations suggestive of toxic effects. The parasite load reduction might be related to NO production, since this molecule is a NO-donor. We observed neither side effects nor elevation of hepatic/renal biomarker levels in the plasma. The data herein presented suggest that the compound should be considered in the development of new drugs for treatment of visceral leishmaniasis. [ABSTRACT FROM AUTHOR]

• Better performance was obtained compared to more commonly used antigens. • Dyn-1 showed excellent ability to identify asymptomatic dogs (100% sensitivity). • Overall, the ability of rDyn-1 to identify dogs with CanL was 97% (sensitivity). • rDyn-1-based ELISA assays could be advantageous over classic diagnostic tests. Visceral leishmaniasis (VL) is a fatal manifestation of an infection caused by intracellular protozoa of the Leishmania genus. In New World countries, VL is classified as a zoonotic disease with domestic dogs acting as its main reservoir. Asymptomatic dogs are as competent to transmit Leishmania to the vectors as symptomatic dogs, however current diagnostic tests are limited and present low sensitivity for this important group. The development of accurate tests is fundamental to the early diagnosis, treatment, and control of canine leishmaniasis. In this study, we investigated the use of a recombinant protein (dynamin-1-like protein, Dyn-1) from L. infantum, as a potential target antigen for leishmaniasis serodiagnosis in both symptomatic and asymptomatic dogs. The antigenic performance of the protein was evaluated by means of ELISA assays using sera from symptomatic (n = 25), asymptomatic (n = 34) and non-infected dogs (n = 36) using ELISA. In addition, sera from dogs experimentally infected with Trypanosoma cruzi (n = 49) and naturally infected with Babesia sp. (n = 8) were tested to evaluate possible cross-reactivity. A crude soluble antigen (CSA) of Leishmania was used as an antigen control and K39 and K26 were used as reference antigens because they are already widely used in commercial tests. rDyn-1-based assay showed the highest sensitivity (97%) compared to the antigens K39 (88%), K26 (86%) and crude extract (95%). The highest specificity among the tests was also obtained with the protein rDyn-1 (94%), compared with the other antigens K39 (81%), K26 (87%), and crude extract (77%). This study showed that the rDyn-1 ELISA assay was able to identify 100% of asymptomatic dogs, establishing its potential as a target for the diagnosis of canine leishmaniasis. [ABSTRACT FROM AUTHOR]

The leishmaniasis are a group of vector-borne diseases caused by a protozoan parasite from the genus Leishmania. In this study, a series of thiazolopyrimidine derivatives were designed and synthesized as novel antileishmanial agents with Lm PTR1 inhibitory activity. The final compounds were evaluated for their in vitro antipromastigote activity, Lm PTR1 and h DHFR enzyme inhibitory activities, and cytotoxicity on RAW264.7 and L929 cell lines. Based on the bioactivity results, three compounds, namely L24f , L24h and L25c , were selected for evaluation of their in vivo efficacy on CL and VL models in BALB/c mice. Among them, two promising compounds, L24h and L25c, showed in vitr o antipromastigote activity against L. tropica with the IC 50 values of 0.04 μg/ml and 6.68 μg/ml; against L. infantum with the IC 50 values of 0.042 μg/ml and 6.77 μg/ml, respectively. Moreover, the title compounds were found to have low in vitro cytotoxicity on L929 and RAW264.7 cell lines with the IC 50 14.08 μg/ml and 21.03 μg/ml, and IC 50 15.02 μg/ml and 8.75 μg/ml, respectively. Lm PTR1 enzyme inhibitory activity of these compounds was determined as 257.40 μg/ml and 59.12 μg/ml and their selectivity index (SI) over h DHFR was reported as 42.62 and 7.02, respectively. In vivo studies presented that L24h and L25c have a significant antileishmanial activity against footpad lesion development of CL and at weight measurement of VL group in comparison to the reference compound, Glucantime®. Also, docking studies were carried out with selected compounds and other potential Leishmania targets to detect the putative targets of the title compounds. Taken together, all these findings provide an important novel lead structure for the antileishmanial drug development. [Display omitted] • A series of thiazolopyrimidine derivatives were synthesized as novel antileishmanials. • L24f , L24h and L25c showed in vitro antipromastigote activity and low cytotoxicity. • L24f , L24h and L25c showed moderate Lm PTR1 inhibition and h DHFR selectivity. • L24h and L25c have shown in vivo activity on CL and VL models of BALB/c mice. [ABSTRACT FROM AUTHOR]

Leishmaniases are parasitic diseases frequent in the Mediterranean Basin. Visceral leishmaniasis (VL) is a notifiable parasitic disease that increased in incidence in Morocco over the past few years and has recently emerged in several new foci, causing a public health problem in Morocco. The aim of this study is to describe the spatio-temporal distribution of VL in Morocco between 1990 and 2014 period in order to highlight important features and trends of VL and its epidemiology and to assess whether the activity of the unit reflects the situation of the disease at the national level and whether it could constitute an indicator of public health relevance. Two thousand four hundred and twenty one cases were reported in Morocco between 1990 and 2014 with an average annual reported incidence rate of 0.4 cases per 100.000 inhabitants. Before 1996 the average annual incidence of VL was 50 cases on average. After this date the number of cases increased and then remained stable with around 100–150 cases per year. Children whose age varies between 1 and 4 years old are the most affected with 1327 (74%) of total cases; nevertheless the adult starts to be affected by the disease. In 2000, 65% of positive cases of VL are concentrated at both northern regions: Taza-Al Hoceima- Taounate with 45% of cases, Tanger- Tetouan mainly represented by Chefchaoun with 20% of cases. The Fez-Boulemane region located in the center recorded 12% of cases. Throughout the years the map VL distribution has been progressively changed and spatial spread of the disease to the center is noted in 2007. 2014 has been marked by an even greater extension of the disease to the center and south of Morocco. Nationally in 2014, 34 of 75 provinces and prefectures are affected compared to 2000, when 22 out of 82 provinces and prefectures were affected. Leishmania infantum was identified the causative agent based on species- specific PCR-Lei70 assay. VL remains a sporadically endemic parasitic disease in Morocco with a progressive extension of its range of distribution. Such a situation would relate to the geographical succession of Phlebotomine sand fly vectors, the difficulty of actions against the canine population reservoirs of L. infantum and unfavorable socio-economic factors. [ABSTRACT FROM AUTHOR]

Background: The aim of present study was to evaluate the protective efficacy of live recombinant L. tarentolae expressing KMP11-NTGP96-GFP fusion as candidates for live engineered recombinant vaccine against visceral leishmaniasis in BALB/c mice. Methods: KMP-11 and NT-GP96 genes cloned into the pJET1.2/blunt cloning vector and then into pEGFP-N1 expression vector. The KMP-11, NT-GP96 and GFP fused in pEGFP-N1 and subcloned into Leishmanian pLEXSY-neo vector. Finally this construct was transferred to L. tarentolae by electroporation. Tranfection was confirmed by SDS-PAGE, WESTERN blot, flowcytometry and RT-PCR. Protective efficacy of this construct was evaluated as a vaccine candidate against visceral leishmaniasis. Parasite burden, humoral and cellular immune responses were assessed before and at 4 weeks after challenge. Results: KMP- NT-Gp96-GFP Fusion was cloned successfully into pLEXSY -neo vector and this construct successfully transferred to L. tarentolae. Finding indicated that immunization with L. tarentolae tarentolae-KMP11-NTGP96-GFP provides significant protection against visceral leishmaniasis and was able to induce an increased expression of IFN- and IgG2a. Following challenge, a reduced parasite load in the spleen of the KMP11-NTGP96-GFP immunized group was detected. Conclusion: The present study is the first to use a combination of a Leishmania antigen with an immunologic antigen in live recombinant L. tarentolae and results suggest that L. tarentolae-KMP11-NTGP96-GFP could be considered as a potential tool in vaccination against visceral leishmaniasis and this vaccination strategy could provide a potent rout for future vaccine development. [ABSTRACT FROM AUTHOR]

Abstract: Over a period of ten years, a series of 694 Leishmania strains from Tunisian leishmaniasis foci were isolated and identified by isoenzymatic analysis. Strains were obtained from human cutaneous and visceral leishmaniasis in immunocompetent subjects, visceral leishmaniasis in imunocompromised individuals and from dogs with visceral leishmaniasis. Two classically dermotropic species, Leishmania (L.) major and Leishmania killicki were found. L. major with the single zymodeme MON-25 was the most isolated in cutaneous leishmaniasis foci of the Centre and South of Tunisia with a recent northern extension. L. killicki zymodeme MON-8 was sporadically found both in its classical microfocus of Tataouine in southeastern Tunisia as well as in some new foci in Southwestern, Central and Northern Tunisia. Leishmania infantum with its three zymodemes MON-1, MON-24 and MON-80 was isolated from both visceral and cutaneous human cases. The majority of L. infantum strains were found in the Northern part of the country; however, some strains were reported for the first time in the Southern part. L. infantum MON-1 was the only zymodeme isolated from canine leishmaniasis. [Copyright &y& Elsevier]

The background of this article is as follows: Few data are available about the persistence of serum-specific IgG antibodies to L. infantum after acute VL. The objective of this article is to evaluate the persistence of antibodies against L. infantum in patients healed from acute VL, and the kinetic of the same antibodies observed in 2 cases of VL relapse and 2 cases of resistance to therapy. The methods which we used to obtain our objective are the following: 55 apparently immunocompetent, HIV-negative patients were examined for antibodies to L. infantum by IFAT over 14 years period, and we got the following results: Serum-specific IgG antibodies titers decrease slowly, but constantly. In the patients with a diagnosis of VL relapse, the kinetic of antibodies was characterized by an initial reduction, and a subsequent antibody levels rapidly increase, while in the patients with a clinical and parasitological diagnosis of VL not responding to specific therapy, we demonstrated persistent high level of antibodies to L. infantum. Finally, we conclude that specific antibodies to L. infantum might persist for many years, and decrease slowly, but steadily. The persistence of these specific antibodies is not related to poor therapeutic response or prognosis, but an acute increase in their levels might be a sentinel of a VL relapse, while persistence of high antibody levels could suggest a resistance to therapy. [ABSTRACT FROM AUTHOR]

Introduction: Visceral leishmaniasis (VL) or Kala-azar is an important parasitic diseases caused by protozoan parasites of the genus Leishmania including L. donovani, L. infantum. Epidemiological evidences show that VL is frequently common in some areas of Jahrom district in Fars Province. This study aimed to characterize the causative agent of VL in this region. Materials and Methods: Bone marrow sample was obtained from 16 VL patients from Pediatric hospital in Jahrom town. DNA was extracted from the microscopic slides and checked by specific PCR to find out the species of the parasite. To do it, a segment of minicirclekinetoplast DNA was amplified, using LINR4 and LIN17 primers. Products of PCR were evaluated by electrophoresis, using 1.5% agarose. Results: Anti-leishmania antibody was detected in all patients by IFAT. Examination of bone marrow smears demonstrated numerous amastigotes ofLeishmania (Leishman bodies) in the samples. All the samples produced a 720 bp band in PCR assay. The isolates were compared with reference strains and revealed that all the isolates are L. infantum. Conclusion: Our findings showed that species characterization with one-step PCR by L1N17 and L1NR4 is simple and fast; it was also confirmed that the causative agent of VL in Jahrom is L. infantum. [ABSTRACT FROM AUTHOR]

Abstract: We have performed a combination of microcapillary cultivation method and restriction fragment length polymorphism (RFLP) analysis of amplified products by 1 single PCR of miniexon region of Leishmania for molecular diagnosis and genotyping of different Leishmania species isolated from cutaneous leishmaniasis (CL) and visceral leishmaniasis. We have analyzed 10 microcapillary cultivated isolates from cutaneous cases and 5 microcapillary cultivated isolates from visceral cases (totally 15) by polymerase chain reaction–RFLP (PCR-RFLP). Of 10 isolates, 3 (30%) were genotyped as Leishmania infantum and 7 (70%) of 10 isolates were genotyped as Leishmania tropica from the microcapillary cultivated isolates of cutaneous cases. On the other hand, all 5 isolates (100%) were genotyped as L. infantum from microcapillary cultivated visceral cases. Our most interesting finding is the presence of 3 L. infantum isolates in CL cases without kala-azar history. Therefore, we suggest that further investigations must be done about this subject. On the other hand, we suggest the combination of microcapillary culture method and PCR-RFLP of miniexon region of leishmaniae can be used in routine laboratory experimentation because of their simple, cheap, and rapid benefits (within a week), whereas other different approaches offer a multitude of valid taxonomic characters for species identification. [Copyright &y& Elsevier]

It is estimated that there are 400000 new cases of visceral leishmaniasis each year, with about 30,000 deaths. Therefore, detection of this pathogen and its species is highly vital for overall health of the community. In the present research, a DNA-based biosensor, namely genosensor, was introduced for detection of genomic DNA of Leishmania infantum. The genosensor was fabricated based on the transduction of cadmium sulfide nanosheets and recognition of a particular single stranded DNA sequence, and worked in label-, marker-, tag- and PCR-free manners. Impedimetric measurements were performed in a wide range of frequency (recording Nyquist diagrams) without applying external force (working at open circuit potential) upon hybridization of DNA targets with the cadmium sulfide nanosheets surface-immobilized probe. The genosensor detected the complementary DNA strand in a concentration range of 1.0 × 10−14 to 1.0 × 10−6 mol L−1 and a detection limit (DL) of 0.81 fmol L−1 (6.5 fg mL−1), and genomic DNA of Leishmania infantum in a concentration range of 5–50 ng μL−1 and a DL of 1.2 ng μL−1. The genosensor had a very good selectivity, fabrication reproducibility and stability, and was applicable for practical applications. Image 1 • A specific DNA sequence was selected from gene sequence of Leishmania infantum. • The DNA sequence was immobilized on cadmium sulfide nanosheets to fabricate a genosensor. • The genosensor detected targets with a nice selectivity. • Leishmania infantum genomic DNA was quantified by the genosensor in clinical samples. [ABSTRACT FROM AUTHOR]