ABSTRACT
Cutaneous leishmaniasis is atypical in Sri Lanka because Leishmania donovani, which typically causes visceral disease, is the causative agent. The origins of recently described hybrids between L. donovani and other Leishmania spp. usually responsible for cutaneous leishmaniasis remain unknown. Other endemic dermotropic Leishmania spp. have not been reported in Sri Lanka. Genome analysis of 27 clinical isolates from Sri Lanka and 32 Old World Leishmania spp. strains found 8 patient isolates clustered with L. tropica and 19 with L. donovani. The L. tropica isolates from Sri Lanka shared markers with strain LtK26 reported decades ago in India, indicating they were not products of recent interspecies hybridization. Because L. tropica was isolated from patients with leishmaniasis in Sri Lanka, our findings indicate L. donovani is not the only cause of cutaneous leishmaniasis in Sri Lanka and potentially explains a haplotype that led to interspecies dermotropic L. donovani hybrids.
Subject(s)
Leishmania tropica , Leishmaniasis, Cutaneous , Whole Genome Sequencing , Sri Lanka , Humans , Leishmania tropica/genetics , Leishmania tropica/isolation & purification , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Cutaneous/diagnosis , Phylogeny , Genome, Protozoan , Male , Female , Leishmania donovani/genetics , Leishmania donovani/isolation & purification , Adult , Middle AgedABSTRACT
According to the World Health Organization (WHO), leishmaniasis is a zoonotic/anthroponotic parasitic disease endemic in 99 countries. It is estimated that approximately 12 million people are infected with Leishmania spp. and 350 million people live at risk. Every year, two million new cases are added to these figures. One and a half million cases of zoonotic/anthroponotic cutaneous leishmaniasis and 500 000 cases of visceral leishmaniasis are reported annually. One person is estimated to to be infected with cutaneous leishmaniasis in every 20 seconds and visceral leishmaniasis causes 60 000 deaths. In this report, two pediatric cases diagnosed with visceral leishmaniasis were presented. In the study, bone marrow aspirations were performed to determine the etiology of the disease in an eight-month-old male patient with fever and hepatosplenomegaly who had been followed up in Manisa Celal Bayar University, Department of Pediatrics, Division of Pediatric Hematology with the diagnosis of severe glucose-6-phosphate dehydrogenase (G-6PD) deficiency since the neonatal period and in a nine-month-old female patient who had had a high fever and bicytopenia for two weeks. Bone marrow aspirations were cultured in NNN medium and their smears were stained and examined with Giemsa. rk-39 and Leishmania IFAT tests were performed by using patients' sera. Quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) analysis was also performed for Leishmania spp. Leishmania spp. amastigotes were observed in Giemsa-stained smear preparations, Leishmania spp. promastigotes were grown in NNN medium, rk39 rapid diagnostic kit was weakly positive, Leishmania IFAT was positive at a titer of 1/1024 and Leishmania tropica was identified as the causative agent by RT-qPCR analysis for both cases. These two cases suggested that fatal cases of visceral leishmaniasis may increase with the spread of visceralized isolates of L.tropica, the most common causative agent of cutaneous leishmaniasis in Türkiye, and this issue may create a significant public health problem.
Subject(s)
Leishmania tropica , Leishmaniasis, Visceral , Humans , Male , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/parasitology , Leishmania tropica/isolation & purification , Leishmania tropica/genetics , Female , Infant , Bone Marrow/parasitology , Glucosephosphate Dehydrogenase Deficiency/complications , AnimalsABSTRACT
Cutaneous leishmaniasis (CL), a neglected tropical disease, is a major public health concern in Yemen, with Leishmania tropica identified as the main causative agent. This study aims to investigate the occurrence and distribution of Leishmania parasites in domestic and wild animals in CL endemic areas in the western highlands of Yemen. A cross-sectional study was conducted in the Utmah District of western Yemen. Blood and skin scraping specimens were collected from 122 domestic and wild animals and tested for the Leishmania DNA using internal transcribed spacer 1 (ITS1) nested polymerase chain reaction. Phylogenetic analyses were performed on 20 L. tropica sequences obtained from animals in this study and 34 sequences from human isolates (collected concurrently from the same study area) retrieved from the GenBank. Overall, L. tropica was detected in 16.4% (20/122) of the examined animals, including 11 goats, two dogs, two bulls, one cow, one donkey, one rabbit, one rat and one bat. None of the examined cats and sheep was positive. The animal sequences were segregated into four different L. tropica haplotypes, with the majority of the animal (15/20) and human (32/34) sequences composed of one dominant haplotype/genotype. These findings represent the first confirmed evidence of natural L. tropica infections in different kinds of domestic and wild animals in western Yemen, suggesting these animals potentially have a role in the transmission of CL in Yemen. Therefore, a One Health approach is required for the effective prevention and control of this devastating disease among endemic populations.
Subject(s)
Animals, Domestic , Animals, Wild , Leishmania tropica , Leishmaniasis, Cutaneous , One Health , Phylogeny , Animals , Leishmania tropica/genetics , Leishmania tropica/isolation & purification , Leishmania tropica/classification , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/veterinary , Leishmaniasis, Cutaneous/parasitology , Yemen/epidemiology , Humans , Cross-Sectional Studies , Animals, Wild/parasitology , Animals, Domestic/parasitology , DNA, Protozoan/genetics , Neglected Diseases/parasitology , Neglected Diseases/epidemiology , Neglected Diseases/veterinary , Endemic Diseases/veterinary , DNA, Ribosomal Spacer/genetics , Polymerase Chain Reaction/veterinary , Sequence Analysis, DNA , MaleSubject(s)
Leishmania tropica , Phlebotomus , Plasmids , Salivary Proteins and Peptides , Leishmania tropica/genetics , Animals , Phlebotomus/genetics , Phlebotomus/parasitology , Salivary Proteins and Peptides/genetics , Salivary Proteins and Peptides/metabolism , Plasmids/genetics , Insect Proteins/genetics , Insect Proteins/metabolism , Mice , Humans , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Cutaneous/prevention & control , FemaleABSTRACT
This study investigated nine provinces in northern Morocco and collected 275 skin scraping, 22 bone marrow aspirates, and 89 fine needle aspirations from suspected cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL) patients and potentially infected dogs. Molecular analysis using ITS1 RFLP PCR and RT-PCR revealed a higher prevalence of L. infantum (66.18 %; χ2 = 28.804; df = 1; P-value = 8.01e-08) than L. tropica in skin scraping, with L. infantum being the sole causative agent for both VL and canine leishmaniasis. L. infantum was predominantly found in most provinces, while L. tropica was relatively more dominant in Taza Province. Discriminant Analysis of Principal Components (DAPC) revealed distinct clustering between L. tropica and the other three species. However, no small subset of SNPs could clearly differentiate between Infantum_CL, Infantum_VL, and CanL, as they likely share a significant genetic background. The high rate of L. infantum could be attributed to the abundance of sand fly species transmitting VL. In Taza Province, Phlebotomus sergenti, responsible for anthroponotic CL, is the most abundant species. DNA sequencing demonstrated sequence heterogeneity in L. infantum (variants 1-9) and L. tropica (variants 1-7). Phylogenetic analysis showed a distinct separation between L. tropica and L. infantum strains, with an overlap among L. infantum strains isolated from cutaneous, visceral, and canine cases, and dogs serving as the central population for L. infantum.
Subject(s)
Dog Diseases , Genetic Variation , Leishmania infantum , Leishmania tropica , Leishmaniasis, Visceral , Dogs , Animals , Leishmania infantum/genetics , Leishmania infantum/isolation & purification , Leishmania tropica/genetics , Leishmania tropica/isolation & purification , Morocco , Humans , Dog Diseases/parasitology , Dog Diseases/genetics , Leishmaniasis, Visceral/veterinary , Leishmaniasis, Visceral/parasitology , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Cutaneous/veterinary , Leishmaniasis, Cutaneous/epidemiology , Phylogeny , Male , Polymorphism, Single NucleotideABSTRACT
BACKGROUND: In the Mediterranean basin, three Leishmania species have been identified: L. infantum, L. major and L. tropica, causing zoonotic visceral leishmaniasis (VL), zoonotic cutaneous leishmaniasis (CL) and anthroponotic CL, respectively. Despite animal models and genomic/transcriptomic studies provided important insights, the pathogenic determinants modulating the development of VL and CL are still poorly understood. This work aimed to identify host transcriptional signatures shared by cells infected with L. infantum, L. major, and L. tropica, as well as specific transcriptional signatures elicited by parasites causing VL (i.e., L. infantum) and parasites involved in CL (i.e., L. major, L. tropica). METHODOLOGY/PRINCIPAL FINDINGS: U937 cells differentiated into macrophage-like cells were infected with L. infantum, L. major and L. tropica for 24h and 48h, and total RNA was extracted. RNA sequencing, performed on an Illumina NovaSeq 6000 platform, was used to evaluate the transcriptional signatures of infected cells with respect to non-infected cells at both time points. The EdgeR package was used to identify differentially expressed genes (fold change > 2 and FDR-adjusted p-values < 0.05). Then, functional enrichment analysis was employed to identify the enriched ontology terms in which these genes are involved. At 24h post-infection, a common signature of 463 dysregulated genes shared among all infection conditions was recognized, while at 48h post-infection the common signature was reduced to 120 genes. Aside from a common transcriptional response, we evidenced different upregulated functional pathways characterizing L. infantum-infected cells, such as VEGFA-VEGFR2 and NFE2L2-related pathways, indicating vascular remodeling and reduction of oxidative stress as potentially important factors for visceralization. CONCLUSIONS: The identification of pathways elicited by parasites causing VL or CL could lead to new therapeutic strategies for leishmaniasis, combining the canonical anti-leishmania compounds with host-directed therapy.
Subject(s)
Leishmania infantum , Leishmania major , Leishmania tropica , Leishmaniasis, Cutaneous , Leishmaniasis, Visceral , Animals , Humans , Leishmania tropica/genetics , Leishmania infantum/genetics , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Visceral/parasitology , MacrophagesABSTRACT
Leishmaniasis is a neglected tropical disease infecting the world's poorest populations. Miltefosine (ML) remains the primary oral drug against the cutaneous form of leishmaniasis. The ATP-binding cassette (ABC) transporters are key players in the xenobiotic efflux, and their inhibition could enhance the therapeutic index. In this study, the ability of beauvericin (BEA) to overcome ABC transporter-mediated resistance of Leishmania tropica to ML was assessed. In addition, the transcription profile of genes involved in resistance acquisition to ML was inspected. Finally, we explored the efflux mechanism of the drug and inhibitor. The efficacy of ML against all developmental stages of L. tropica in the presence or absence of BEA was evaluated using an absolute quantification assay. The expression of resistance genes was evaluated, comparing susceptible and resistant strains. Finally, the mechanisms governing the interaction between the ABC transporter and its ligands were elucidated using molecular docking and dynamic simulation. Relative quantification showed that the expression of the ABCG sub-family is mostly modulated by ML. In this study, we used BEA to impede resistance of Leishmania tropica. The IC50 values, following BEA treatment, were significantly reduced from 30.83, 48.17, and 16.83 µM using ML to 8.14, 11.1, and 7.18 µM when using a combinatorial treatment (ML + BEA) against promastigotes, axenic amastigotes, and intracellular amastigotes, respectively. We also demonstrated a favorable BEA-binding enthalpy to L. tropica ABC transporter compared to ML. Our study revealed that BEA partially reverses the resistance development of L. tropica to ML by blocking the alternate ATP hydrolysis cycle.
Subject(s)
ATP-Binding Cassette Transporters , Antiprotozoal Agents , Depsipeptides , Drug Resistance , Leishmania tropica , Molecular Docking Simulation , Phosphorylcholine , Phosphorylcholine/analogs & derivatives , Leishmania tropica/drug effects , Leishmania tropica/genetics , ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/metabolism , ATP-Binding Cassette Transporters/antagonists & inhibitors , Depsipeptides/pharmacology , Antiprotozoal Agents/pharmacology , Phosphorylcholine/pharmacology , Humans , Protozoan Proteins/genetics , Protozoan Proteins/metabolism , Protozoan Proteins/antagonists & inhibitorsABSTRACT
In Morocco, cutaneous leishmaniasis (CL) caused by Leishmania (L.) tropica is an important health problem. Despite the high incidence of CL in the country, the genomic heterogeneity of these parasites is still incompletely understood. In this study, we sequenced the genomes of 14 Moroccan isolates of L. tropica collected from confirmed cases of CL to investigate their genomic heterogeneity. Comparative genomics analyses were conducted by applying the recently established Genome Instability Pipeline (GIP), which allowed us to conduct phylogenomic and principal components analyses (PCA), and to assess genomic variations at the levels of the karyotype, gene copy number, single nucleotide polymorphisms (SNPs) and small insertions/deletions (INDELs) variants. Read-depth analyses revealed a mostly disomic karyotype, with the exception of the stable tetrasomy of chromosome 31. In contrast, we identified important gene copy number variations across all isolates, which affect known virulence genes and thus were probably selected in the field. SNP-based cluster analysis of the 14 isolates revealed a core group of 12 strains that formed a tight cluster and shared 45.1â% (87â751) of SNPs, as well as two strains (M3015, Ltr_16) that clustered separately from each other and the core group, suggesting the circulation of genetically highly diverse strains in Morocco. Phylogenetic analysis, which compared our 14 L. tropica isolates against 40 published genomes of L. tropica from a diverse array of locations, confirmed the genetic difference of our Moroccan isolates from all other isolates examined. In conclusion, our results indicate potential regional variations in SNP profiles that may differentiate Moroccan L. tropica from other L. tropica strains circulating in endemic countries in the Middle East. Our report paves the way for future research with a larger number of strains that will allow correlation of diverse phenotypes (resistance to treatments, virulence) and origins (geography, host species, year of isolation) to defined genomic signals such as gene copy number variations or SNP profiles that may represent interesting biomarker candidates.
Subject(s)
Leishmania tropica , Leishmaniasis, Cutaneous , Humans , Leishmania tropica/genetics , Phylogeny , DNA Copy Number Variations , Morocco/epidemiology , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/parasitology , GenomicsABSTRACT
Pentavalent antimonials are the mainstay treatment against different clinical forms of leishmaniasis. The emergence of resistant isolates in endemic areas has led to treatment failure. Unraveling the underlying resistance mechanism would assist in improving the treatment strategies against resistant isolates. This study aimed to investigate the RNA expression level of glutathione synthetase (GS), Spermidine synthetase (SpS), trypanothione synthetase (TryS) genes involved in trypanothione synthesis, and thiol-dependent reductase (TDR) implicated in drug reduction, in antimony-sensitive and -resistant Leishmania tropica isolates. We investigated 11 antimony-resistant and 11 antimony-sensitive L. tropica clinical isolates from ACL patients. Drug sensitivity of amastigotes was determined in mouse macrophage cell line J774A.1. The RNA expression level in the promastigote forms was analyzed by quantitative real-time PCR. The results revealed a significant increase in the average expression of GS, SpS, and TrpS genes by 2.19, 1.56, and 2.33-fold in resistant isolates compared to sensitive ones. The average expression of TDR was 1.24-fold higher in resistant isolates, which was insignificant. The highest correlation coefficient between inhibitory concentration (IC50) values and gene expression belonged to the TryS, GS, SpS, and TDR genes. Moreover, the intracellular thiol content was increased 2.17-fold in resistant isolates compared to sensitive ones and positively correlated with IC50 values. Our findings suggest that overexpression of trypanothione biosynthesis genes and increased thiol content might play a key role in the antimony resistance of L. tropica clinical isolates. In addition, the diversity of gene expression in the trypanothione system and thiol content among L. tropica clinical isolates highlighted the phenotypic heterogeneity of antimony resistance among the parasite population.
Subject(s)
Antimony , Antiprotozoal Agents , Drug Resistance , Glutathione , Glutathione/analogs & derivatives , Leishmania tropica , Spermidine/analogs & derivatives , Leishmania tropica/genetics , Leishmania tropica/drug effects , Drug Resistance/genetics , Animals , Antimony/pharmacology , Humans , Antiprotozoal Agents/pharmacology , Mice , Glutathione/metabolism , Cell Line , Macrophages/parasitology , Inhibitory Concentration 50 , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Cutaneous/drug therapy , Female , Adult , Parasitic Sensitivity Tests , Male , Real-Time Polymerase Chain ReactionABSTRACT
BACKGROUND: Cutaneous leishmaniasis (CL), an emerging vector-borne ailment in Khyber Pakhtunkhwa (KPK), Pakistan, exhibits diverse spread patterns and outbreaks. METHODS: To comprehend its epidemiology and identify parasite species, we conducted an active survey on suspected CL cases (n=8845) in KPK. RESULTS: Microscopy and internal transcribed spacer-1 PCR-restriction fragment length polymorphism (RFLP) molecular techniques detected Leishmania spp. in blood samples. Phylogenetic analysis gauged genetic affinities with other areas. District Bannu displayed the highest CL impact (14.58%), while Swat had the lowest impact (4.33%) among cases. Annual blood examination rate, parasite incidence and slide positivity rate were 4.96 per 1000 people, 0.0233 and 0.047%, respectively. CL infections were prevalent in 1- to 20-y-olds, with males (57.17%) more vulnerable than females (42.82%). Single lesions occurred in 43.73% of patients, while 31.2% people had two lesions, 17.31% had three lesions and 7.74% had more than three lesions. Most had sand-fly exposure but lacked preventive measures like repellents and bed nets. Leishmania tropica was confirmed via RFLP analysis in amplified samples. Phylogenetic analysis unveiled genetic parallels between L. tropica of KPK and isolates from China, Iran, Afghanistan, India, Syria and Morocco. CONCLUSIONS: Urgent comprehensive control measures are imperative. Early detection, targeted interventions and raising awareness of CL and sand-fly vectors are vital for reducing the disease's impact. International collaboration and monitoring are crucial to tackle Leishmania spp.'s genetic diversity and curtail its cross-border spread.
Subject(s)
Leishmania tropica , Leishmaniasis, Cutaneous , Phlebotomus , Psychodidae , Male , Female , Animals , Humans , Phylogeny , Pakistan/epidemiology , Sand , Polymerase Chain Reaction , Leishmaniasis, Cutaneous/epidemiology , Leishmania tropica/genetics , Phlebotomus/parasitology , Psychodidae/parasitology , Polymorphism, Restriction Fragment LengthABSTRACT
BACKGROUND AND AIMS: Leishmaniasis is a neglected tropical infection caused by Leishmania parasite that affect human and animal. In Morocco, the cutaneous leishmaniasis has spread substantially to the new areas. The surveillance limited to active foci may underestimate the occurrence of cutaneous leishmaniasis (CL). This study aims to investigate the local transmission of CL in rural districts of Youssoufia province, central Morocco, as a potential focus of CL. METHODS: For this purpose, parasitological, molecular and entomological investigations were carried out in this area. Data collection concerns potential vectors and human cases. Thus, 402 patients were examined for suspected leishmaniasis lesions in three localities of the province of Youssoufia. In these same localities, 983 sand flies were collected by CDC light traps and sticky paper during one-night per month during 6 months. These sand flies were all identified morphologically using the Moroccan identification key. RESULTS: The results showed that among the 25 skin lesions detected in a population of 402 individuals, 18 were confirmed by kDNA nested PCR as CL positive patients, of which only 25% were positive by direct examination. Leishmania tropica and Leishmania major were identified as causative agents of CL in the study area. Direct parasitological examination showed a low sensitivity (27.78%), especially for L. major, although its specificity was evaluated at 100%. Regarding entomological results, both genera of the Moroccan sand fly were collected in the study area: Genus/Phlebotomus (75.28%) and Sergentomyia (24.72%). Phlebotomus (P) papatasi, the proven vector of L. major, was the most abundant species (33.98%), followed by Paralongicollum sergenti (22.58%), the confirmed vector of L. tropica; while Sergentomyia (S) minuta, P. longicuspis, S. fallax and P. kazeruni were collected with, respectively, 17.60%, 16.99%, 7.12% and 1.73%. CONCLUSION: This study constitutes the first report of CL in the study areas, as well as the coexistence of L. tropica and L. major in these rural localities. Local transmission of CL is highly probable, as indicated by the prevalence of the two proven vectors of L. major and L. tropica. To control the spread of this disease, our results suggest the use of highly sensitive molecular methods to detect CL cases in potential leishmaniasis foci, which will improve surveillance.
Subject(s)
Leishmania tropica , Leishmaniasis, Cutaneous , Phlebotomus , Psychodidae , Humans , Animals , Morocco/epidemiology , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Cutaneous/veterinary , Psychodidae/parasitology , Phlebotomus/parasitology , Leishmania tropica/geneticsABSTRACT
Cutaneous Leishmaniasis is endemic in the tribal district of Khyber near the Pak-Afghan border and is caused by Leishmania tropica. In Pakistan, cutaneous leishmaniasis caused by L. tropica is considered anthroponotic and is thought to be maintained by a human-sand fly-human transmission cycle. Along with humans, other mammals may also be acting as reservoir hosts of leishmaniasis in the study area. To investigate the role of non-human mammals in the transmission of leishmaniasis, blood samples were collected from 245 animals from the CL endemic district of Khyber, Pakistan. Leishmania parasite in these samples was detected by amplifying the species-specific sequences in minicircle kinetoplast DNA, using PCR. L. tropica DNA was detected in 18 (7.35%) samples, comprising 11 cows (Bos taurus), 6 goats (Capra hircus), and 1 dog (Canus lupus familiaris). Only a single cow and dog had a leishmaniasis-like lesion, and the remaining positive samples were asymptomatic. None of the tested sheep (Ovis aries) and rat (Rattus rattus, Rattus norvegicus) was positive. The present study reports the first instance of molecular detection of L. tropica in domestic animals. Our study indicates that along with humans' cows, goats and dogs may also be playing an important role in the transmission of anthroponotic cutaneous leishmaniasis in district Khyber in particular and Pakistan in general.
Subject(s)
Leishmania tropica , Leishmaniasis, Cutaneous , Female , Humans , Animals , Rats , Cattle , Dogs , Sheep , Leishmania tropica/genetics , Pakistan/epidemiology , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/veterinary , Leishmaniasis, Cutaneous/diagnosis , Animals, Domestic , GoatsABSTRACT
Leishmania tropica is a vector-borne parasitic protozoa that is the leading cause of leishmaniasis throughout the global tropics and subtropics. L. tropica is a multidrug-resistant parasite with a diverse set of serological, biochemical, and genomic features. There are currently no particular vaccines available to combat leishmaniasis. The present study prioritized potential vaccine candidate proteins of L. tropica using subtractive proteomics and vaccinomics approaches. These vaccine candidate proteins were downstream analyzed to predict B- and T-cell epitopes based on high antigenicity, non-allergenic, and non-toxic characteristics. The top-ranked overlapping MHC-I, MHC-II, and linear B-cell epitopes were prioritized for model vaccine designing. The lead epitopes were linked together by suitable linker sequences to design multi-epitope constructs. Immunogenic adjuvant sequences were incorporated at the N-terminus of the model vaccine constructs to enhance their immunological potential. Among different combinations of constructs, four vaccine designs were selected based on their physicochemical and immunological features. The tertiary structure models of the designed vaccine constructs were predicted and verified. The molecular docking and molecular dynamic (MD) simulation analyses indicated that the vaccine design V1 demonstrated robust and stable molecular interactions with toll-like receptor 4 (TLR4). The top-ranked vaccine construct model-IV demonstrated significant expressive capability in the E. coli expression system during in-silico restriction cloning analysis. The results of the present study are intriguing; nevertheless, experimental bioassays are required to validate the efficacy of the predicted model chimeric vaccine.
Subject(s)
Leishmania tropica , Vaccines , Molecular Docking Simulation , Leishmania tropica/genetics , Proteomics , Escherichia coli , Epitopes, T-LymphocyteABSTRACT
Millions of people worldwide are affected by cutaneous leishmaniasis (CL), a disease that has a significant impact on morbidity and mortality. Understanding the immune responses responsible for tissue damage or the process of lesion healing plays a pivotal role in shaping optimal treatment strategies. In this study, we investigated immunological phenotypes for three groups: glucantime treated (n = 30) and untreated (n = 30) CL patients infected with Leishmania tropica (L. tropica), and healthy controls (n = 20). T-lymphocytes (CD4+ and CD8+), and B lymphocytes (CD14+ and CD19+) were isolated using antibody-conjugated microbeads and magnetic field isolation to achieve high purity. A higher significant difference was observed between T-lymphocytes (CD4+ and CD8+), and B-lymphocytes (CD14+ and CD19+) cells in CL-infected groups before and after treatment (p < 0.0001). When compared, there was also a significant difference among T-lymphocytes (CD4+ and CD8+), B lymphocytes (CD14+ and CD19+) p < 0.0001, p < 0.0005, and p < 0.0007, respectively between CL-infected individuals (before and after treatment) to controls. Our findings suggest that an increased proportion of these cells seen in treated patients may mediate healing, while it is also possible that they may contribute to tissue injury. Understanding the immune system and lesion size of CL can help develop immunotherapies and comprehend the evolution of this parasitic disease.
Subject(s)
Leishmania tropica , Leishmaniasis, Cutaneous , Humans , Leishmania tropica/genetics , Meglumine Antimoniate/therapeutic useABSTRACT
Leishmania RNA virus (LRV) is a double-stranded RNA (dsRNA) virus that is thought to contribute to the severe inflammatory response of the causative Leishmania parasite in the mammalian host by being present in many isolates of Leishmania spp. In our study, it was aimed to obtain data on the presence of Leishmania RNA Virus 2 (LRV2), which is thought to cause a change in the clinical course of leishmaniasis, in Leishmania major and Leishmania tropica isolates isolated from cutaneous leishmaniasis (CL) patients in Türkiye. Leishmania strains stored in liquid nitrogen tank by cryopreservation in Manisa Celal Bayar University Faculty of Medicine Parasite Bank were resuscitated under suitable conditions and cultivated in NNN and RPMI-1640 media. Then, the isolates were allowed to enter the logarithmic phase in a 26ºC incubator and DNA isolations were made using the "High Pure PCR Template Preparation Kit". Real-time polymerase chain reaction (Rt-PCR) melting analyzes were applied to the DNAs obtained by using primers and probes specific to the internal transcribed spacer-1 (ITS-1) gene region of Leishmania. After RNA isolation from promastigote suspension, cDNA synthesis was performed by reverse transcription. After gel electrophoresis with PCR amplification products, dsRNA band formation was evaluated in terms of LRV2 positivity under ultraviolet light. Among the 20 examined Leishmania spp. isolates (10 L.tropica and 10 L.major), four (three L.tropica, one L.major) were found to be positive for the presence of LRV2. Although the mechanism of LRV in recent studies has not been fully understood, it is known that it exacerbates the clinic of the disease and even has an effect on the formation of drug resistance by the parasite. It is important to obtain data on the presence of LRV in our country and to contribute to various clinical, drug development, prevalence studies, diagnosis and treatment of the disease in the future.
Subject(s)
Leishmania major , Leishmania tropica , Leishmaniasis, Cutaneous , Leishmaniavirus , RNA Viruses , Animals , Humans , Leishmania major/genetics , Leishmania tropica/genetics , Leishmaniasis, Cutaneous/parasitology , Leishmaniavirus/genetics , Real-Time Polymerase Chain Reaction , RNA Viruses/genetics , Mammals/geneticsABSTRACT
PURPOSE: In Turkey, the main causative agent of visceral leishmaniasis (VL) is Leishmania. infantum and the main causative agent of cutaneous leishmaniasis (CL) is Leishmania tropica. In this study, we aimed to discuss the possible mechanisms, clinical aspects, and threat of visceralizing L. tropica. METHODS: This study includes seven cases of VL caused by L. tropica.Five patients were male (71%) and four were adults (57%). RESULTS: All the VL patients complained of fever and splenomegaly. Fatigue, pancytopenia, and hepatomegaly were present in six patients each (86%), while weight loss and gastrointestinal system (GIS) symptoms were present in 5 patients (71%). CONCLUSIONS: In this study, we have evaluated seven cases of visceralized L. tropica (VLT) in the context of the changing leishmaniasis epidemiology in Turkey. We have evaluated the possible mechanisms of visceralization; inter- and intraspecies genetic exchange with all the old world leishmaniasis agents present in the region, stress induced by inappropriate use of drugs, and possible ongoing adaptation mechanisms of Leishmania spp. The threat posed by VLT is significant as L. tropica is the most widespread and most common cause of leishmaniasis in Turkey. We do not know the vectorial capacity of the sand flies for the transmission of VLT strains or if these strains are in circulation in Turkey. Future studies should be carried out to investigate these issues as the transition of L. tropica from a mild disease-causing agent to a mortal one poses a significant public health concern for Turkey and Europe.
Subject(s)
Leishmania infantum , Leishmania tropica , Leishmaniasis, Cutaneous , Leishmaniasis, Visceral , Male , Female , Humans , Leishmania tropica/genetics , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Cutaneous/epidemiology , Turkey/epidemiologyABSTRACT
Next-generation sequencing (NGS) was used to investigate the genetic diversity of Leishmania tropica in the sand fly vector, targeting the internal transcribed spacer 1 (ITS1) of the genus Leishmania. Bioinformatics analyses were conducted using Galaxy, MEGA version X, DnaSP ver. 6.12.03, and PopART 1.7 software for NGS analysis, phylogenetic tree, genetic diversity, and haplotype networking, respectively. A total of 307 engorged sand flies were trapped, with an overall Leishmania infection rate of 9.4 (29/307) and 6.8% by NGS and ITS1-PCR, respectively. Two Leishmania-infected sand fly genera were identified: Phlebotomus (10.2%, 26/254) and Sergentomyia (5.7% (3/53). The phylogenetic tree showed two clusters, cluster I included the four study sequences along with 25 GenBank-retrieved DNA sequences. Cluster II consisted of three sequences from Iran and Pakistan. The genetic diversity analysis for the 29 L. tropica sequences showed high haplotype (gene) diversity index (Hd) (0.62 ± 0.07) but low nucleotide diversity index (π) (0.04 ± 0.01). Tajima's D, a neutrality test, is more negative in cluster I (D = - 2.0) than in total population (D = - 1.83), but both are equally significant (P < 0.001), indicating that observed variation in cluster I and whole population is less frequent than expected. The median-joining haplotype network produced a total of 11 active haplotypes. In conclusion, L. tropica from sand flies in Palestine is monophyletic that assembled in one main phylogroup and one haplotype.
Subject(s)
Leishmania tropica , Phlebotomus , Psychodidae , Animals , Phlebotomus/genetics , Leishmania tropica/genetics , Haplotypes , Phylogeny , High-Throughput Nucleotide Sequencing , Genetic Variation , TechnologyABSTRACT
INTRODUCTION: In most of the endemic areas, the detection of CL is based on searching for amastigotes using the direct smear method. Since expert microscopists are not usually available in every laboratory, false diagnoses are a disaster that happens. Therefore, the aim of current research is to evaluate the validity of the CL Detect™ Rapid Test (CDRT) for diagnosis CL in comparison to direct smear and polymerase chain reaction (PCR) methods. METHODS: A total of 70 patients with skin lesions suspected to be CL were recruited. Skin samples from the lesions were collected and used for direct microscopic examination and the PCR method. Furthermore, the skin sample was collected in accordance with the manufacturer's instructions for the CDRT-based rapid diagnostic test. RESULTS: Of 70 samples, 51 and 35 samples were positive by direct smear examination and the CDRT, respectively. The PCR showed positive results in 59 samples; 50 and 9 samples were identified as Leishmania major and Leishmania tropica, respectively. The sensitivity and specificity were calculated to be 68.6% (95% CI 54.11-80.89%) and 100% (95% CI 82.35-100%). When the results of CDRT were compared to the microscopic examinations, an agreement of 77.14% was seen between the CDRT and microscopic examination. In addition, the sensitivity and specificity were 59.32% (95% CI 45.75-71.93%) and 100% (95% CI 71.5-100%) when the CDRT was compared to PCR assay (as gold standard) and an agreement (65.71%) was found between CDRT and PCR assay. CONCLUSION: As the CDRT is simple, rapid, and does not require great proficiency, it is recommended for use in the detection of CL caused by L. major or L. tropica as a diagnostic method, especially in areas with limited access to expert microscopists.
Subject(s)
Leishmania major , Leishmania tropica , Leishmaniasis, Cutaneous , Humans , DNA, Protozoan/genetics , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/epidemiology , Leishmania tropica/genetics , Leishmania major/genetics , Polymerase Chain Reaction/methodsABSTRACT
Leishmaniasis is an overlooked, poverty-stricken, and complex disease with growing social and public health problems. In general, leishmaniasis is a curable disease; however, there is an expansion of unresponsive cases to treatment in cutaneous leishmaniasis (CL). One of the effective and ignored determinants in the treatment outcome of CL is poor treatment adherence (PTA). PTA is an overlooked and widespread phenomenon to proper Leishmania treatment. This study aimed to explore the effect of poor adherence in unresponsiveness to treatment in patients with anthroponotic CL (ACL) by comparing conventional statistical modalities and machine learning analyses in Iran. Overall, 190 cases consisting of 50 unresponsive patients (case group), and 140 responsive patients (control group) with ACL were randomly selected. The data collecting form that included 25 queries (Q) was recorded for each case and analyzed by R software and genetic algorithm (GA) approaches. Complex treatment regimens (Q11), cultural and lay views about the disease and therapy (Q8), life stress, hopelessness and negative feelings (Q22), adverse effects of treatment (Q13), and long duration of the lesion (Q12) were the most prevalent significant variables that inhibited effective treatment adherence by the two methods, in decreasing order of significance. In the inherent algorithm approach, similar to the statistical approach, the most significant feature was complex treatment regimens (Q11). Providing essential knowledge about ACL and treatment of patients with chronic diseases and patients with misconceptions about chemical drugs are important issues directly related to the disease's unresponsiveness. Furthermore, early detection of patients to prevent the long duration of the disease and the process of treatment, efforts to minimize side effects of treatment, induction of positive thinking, and giving hope to patients with stress and anxiety by medical staff, and family can help patients adhere to the treatment.
Subject(s)
Leishmania tropica , Leishmaniasis, Cutaneous , Humans , Leishmania tropica/genetics , Iran , Leishmaniasis, Cutaneous/drug therapy , Treatment Outcome , Case-Control StudiesABSTRACT
BACKGROUND: Incidence of Cutaneous Leishmaniasis as an infectious and neglected disease is increasing, for the diagnosis of which several traditional methods and conventional PCR techniques have been developed, employing different genes for species identification. METHODS: Leishmania parasites were sampled, DNA was extracted, and new specific and sensitive primers were designed. Two ITS-rDNA and Cyt b genes were targeted by qPCR using the High- Resolution Melting method to identify Leishmania parasites. The standard curves were drawn, compared, and identified by high-resolution melting curve analysis. RESULTS: Melting temperature and Cycle of Threshold of ITS-rDNA was higher than Cyt b but Cyt b was more sensitive than ITS-rDNA when Leishmania major and Leishmania tropica were analyzed and evaluated. By aligning melt curves, normalizing fluorescence curves, and difference plotting melt curves, each Leishmania species was distinguished easily. L. major and L. tropica were separated at 83.6 °C and 84.7 °C, respectively, with less than 0.9 °C of temperature difference. Developing sensitivity and specificity of real-time PCR based on EvaGreen could detect DNA concentration to less than one pmol. CONCLUSIONS: Precise identification of Leishmania parasites is crucial for strategies of disease control. Real-time PCR using EvaGreen provides rapid, highly sensitive, and specific detection of parasite's DNA. The modified High-Resolution Melting could determine unique curves and was able to detect single nucleotide polymorphisms according to small differences in the nucleotide content of Leishmania parasites.