1
|
Gonzalez-Garcia LN, Rodríguez-Guzmán AM, Vargas-León CM, Aponte S, Bonilla-Valbuena LA, Matiz-González JM, Clavijo-Vanegas AM, Duarte-Olaya GA, Aguilar-Buitrago C, Urrea DA, Duitama J, Echeverry MC. Genomic characterization of Leishmania (V.) braziliensis associated with antimony therapeutic failure and variable in vitro tolerance to amphotericin B. Sci Rep 2025; 15:12973. [PMID: 40234696 PMCID: PMC12000620 DOI: 10.1038/s41598-025-96849-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2024] [Accepted: 04/01/2025] [Indexed: 04/17/2025] Open
Abstract
Leishmaniasis, a vector-borne disease caused by protozoa from the Leishmania genus, presents a wide range of clinical manifestations in humans and varying responses to treatments. The main clinical presentations correspond with visceral leishmaniasis (VL), cutaneous leishmaniasis (CL), and mucosal leishmaniasis (ML). Amphotericin B (AmB) is a second-line therapeutic option in all forms of leishmaniasis with treatment failure or contraindication for Antimony derivates (SbV) therapy and in geographical regions with a high prevalence of SbV-resistant parasites. This study delves into the genomic features of thirteen L. (V.) braziliensis clinical isolates from CL patients who experienced therapeutic failure to SbV treatment. The isolates were categorized based on their AmB in vitro susceptibility in the amastigote stage, the intracellular parasitic form found in the vertebrate host. The whole genome sequences of the isolates were analyzed and compared with the reference genomes of L. (V.) braziliensis (MHOM/BR/75/M2904 and M2903). The average number of heterozygous SNPs in clinical isolates is at least 75% higher than the reference genomes, and the allele dosages suggest an overall ploidy of two, except in chromosome 31. The main mutations associated with AmB resistance previously reported in experimental cell lines from L. (L.) infantum, L. (L.) mexicana, and L. (L.) donovani were not found in this study. However, there were found mutations referred by other authors in parasites resistant to antileishmanial drugs in proteins such as GP63 (leishmanolysin), NADH-ubiquinone oxidoreductase- ESSS subunit- (putative), quinonoid dihydropteridine reductase, 20s proteasome beta 7 subunit- (putative), biopterin transporter- (putative), and common hypothetical proteins. CNV analysis revealed that the isolates most tolerant to AmB present duplications of genomic regions encompassing genes involved in N-Glycan biosynthesis and biopterin/folate transport and metabolism. Therefore, the present study uncovers previously undescribed metabolic pathways that could be involved in the natural AmB tolerance in Leishmania, which need to be functionally evaluated. These findings highlight the need for further drug response studies in field isolates.
Collapse
Grants
- 71090-Contract 80740-441-2020 Ministerio de Ciencia ,Tecnología e inovación, Colombia
- 71090-Contract 80740-441-2020 Ministerio de Ciencia ,Tecnología e inovación, Colombia
- 71090-Contract 80740-441-2020 Ministerio de Ciencia ,Tecnología e inovación, Colombia
- 71090-Contract 80740-441-2020 Ministerio de Ciencia ,Tecnología e inovación, Colombia
- 71090-Contract 80740-441-2020 Ministerio de Ciencia ,Tecnología e inovación, Colombia
- 71090-Contract 80740-441-2020 Ministerio de Ciencia ,Tecnología e inovación, Colombia
- 71090-Contract 80740-441-2020 Ministerio de Ciencia ,Tecnología e inovación, Colombia
- Universidad Nacional de Colombia
- Universidad del Tolima,Colombia
- Universidad de los Andes, Colombia
Collapse
Affiliation(s)
| | | | - Carolina M Vargas-León
- Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia - Sede Bogotá, Bogotá, Colombia
| | - Samanda Aponte
- Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia - Sede Bogotá, Bogotá, Colombia
| | - Liliana A Bonilla-Valbuena
- Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia - Sede Bogotá, Bogotá, Colombia
| | - J Manuel Matiz-González
- Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia - Sede Bogotá, Bogotá, Colombia
| | - Ana M Clavijo-Vanegas
- Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia - Sede Bogotá, Bogotá, Colombia
| | - Germán Andrés Duarte-Olaya
- Laboratorio de Investigaciones en Parasitología Tropical (LIPT), Universidad del Tolima, Ibagué, Colombia
| | - Catherine Aguilar-Buitrago
- Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia - Sede Bogotá, Bogotá, Colombia
| | - Daniel Alfonso Urrea
- Laboratorio de Investigaciones en Parasitología Tropical (LIPT), Universidad del Tolima, Ibagué, Colombia
| | - Jorge Duitama
- Systems and Computing Engineering Department, Universidad de los Andes, Bogotá, Colombia
| | - Maria C Echeverry
- Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia - Sede Bogotá, Bogotá, Colombia.
- Universidad Nacional de Colombia, Of. 303-Edif 471- Cr 30 45 - 03, Bogotá, Colombia.
| |
Collapse
|
2
|
Virginia Batista Vieira A, Farias PCS, Silva Nunes Bezerra G, Xavier AT, Sebastião Da Costa Lima Júnior M, Silva EDD, Barbosa Júnior WL, Medeiros ZM. Evaluation of molecular techniques to visceral leishmaniasis detection in asymptomatic patients: a systematic review. Expert Rev Mol Diagn 2021; 21:493-504. [PMID: 33719847 DOI: 10.1080/14737159.2021.1900736] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Visceral leishmaniasis (VL) is a systemic and neglected parasitic disease. Its main symptoms are fever, splenomegaly with or without hepatomegaly, and anemia, however, most individuals remain asymptomatic. Due to the lack of a gold standard and the limitations of current diagnostic techniques, where parasitology is ethically unfeasible for individuals without symptoms and serological tests do not differentiate between past and present disease, molecular methodologies are the most suitable. AREAS COVERED We performed a systematic review analyzing the molecular techniques based on PCR used, so far, to detect asymptomatic cases of VL in humans. Structured searches were carried out on PubMed, LILACS, Scopus, and Web of Science databases without time and language restrictions. Two reviewers evaluated the studies, performed data extraction, and quality assessment by assigning scores. EXPERT OPINION qPCR using RNA targets can be used in the diagnosis of asymptomatic cases of human VL, due to its characteristics. We recommend further studies to analyze the methodology, mainly observing the use of different rRNA targets. Therefore, we hope that this technique contributed to the construction of public policies that address the diagnosis and handling of asymptomatic patients.
Collapse
Affiliation(s)
- Amanda Virginia Batista Vieira
- Programa De Pós-Graduação Em Ciências Da Saúde, Universidade De Pernambuco (UPE), Recife, Brasil.,Departamento De Parasitologia, Instituto Aggeu Magalhães (IAM), Fundação Oswaldo Cruz (FIOCRUZ), Recife, Brasil
| | | | - Gilberto Silva Nunes Bezerra
- Programa De Pós-Graduação Em Ciências Da Saúde, Universidade De Pernambuco (UPE), Recife, Brasil.,Departamento De Parasitologia, Instituto Aggeu Magalhães (IAM), Fundação Oswaldo Cruz (FIOCRUZ), Recife, Brasil
| | - Amanda Tavares Xavier
- Programa De Pós-Graduação Em Ciências Da Saúde, Universidade De Pernambuco (UPE), Recife, Brasil.,Departamento De Parasitologia, Instituto Aggeu Magalhães (IAM), Fundação Oswaldo Cruz (FIOCRUZ), Recife, Brasil
| | | | - Elis Dionísio Da Silva
- Departamento De Imunologia, Instituto Aggeu Magalhães (IAM), Fundação Oswaldo Cruz (FIOCRUZ), Recife, Brasil
| | - Walter Lins Barbosa Júnior
- Departamento De Parasitologia, Instituto Aggeu Magalhães (IAM), Fundação Oswaldo Cruz (FIOCRUZ), Recife, Brasil
| | - Zulma Maria Medeiros
- Programa De Pós-Graduação Em Ciências Da Saúde, Universidade De Pernambuco (UPE), Recife, Brasil.,Departamento De Parasitologia, Instituto Aggeu Magalhães (IAM), Fundação Oswaldo Cruz (FIOCRUZ), Recife, Brasil
| |
Collapse
|
3
|
Parra-Muñoz M, Aponte S, Ovalle-Bracho C, Saavedra CH, Echeverry MC. Detection of Leishmania RNA Virus in Clinical Samples from Cutaneous Leishmaniasis Patients Varies according to the Type of Sample. Am J Trop Med Hyg 2020; 104:233-239. [PMID: 33146111 DOI: 10.4269/ajtmh.20-0073] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Leishmania RNA virus (LRV) is a double-stranded RNA virus belonging to the Totiviridae family detected as cytoplasmic inclusions in some strains of the human parasite Leishmania spp. Experimental evidence supports the hypothesis that human coinfection with Leishmania spp.-LRV triggers an exacerbated immune response in the host that can be responsible for the observed complicated outcomes in cutaneous leishmaniasis (CL), such as mucosal leishmaniasis (ML) and treatment failure of CL. However, the reported frequencies of LRV associated with complicated outcomes in patient's series are highly variable, diminishing the relevance on the virus presence in the pathogenesis of the disease. To assess whether or not the inconsistent information about the frequency of LRV associated with CL complicated outcomes could be related to the virus detection approach, the present study evaluated the LRV presence in clinical samples using a diagnostic algorithm according to the type of the sample. In 36 samples with diagnosis of complicated forms of CL (15 of ML and 21 of CL antimony treatment failure) and six samples with non-Leishmania spp. infection, the LRV presence was assessed by RT-PCR, RT-qPCR, and nested RT-PCR. Viral load was estimated in parasite clinical isolates. By combining the methods, LRV1 presence was confirmed in 45% (9/20) of isolates and 37.5% (6/16) of the incisional biopsies. Remarkably, in some cases (4/8), LRV1 was undetectable in the isolates but present in their respective biopsies, and less frequently, the opposite was observed (1/8), suggesting the possibility of loss of parasites harboring LRV1 during the in vitro growth.
Collapse
Affiliation(s)
- Marcela Parra-Muñoz
- 1Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Samanda Aponte
- 1Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia
| | | | - Carlos H Saavedra
- 3Departamento de Medicina, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia
| | - María C Echeverry
- 1Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia
| |
Collapse
|
4
|
Pareyn M, Hendrickx R, Girma N, Hendrickx S, Van Bockstal L, Van Houtte N, Shibru S, Maes L, Leirs H, Caljon G. Evaluation of a pan-Leishmania SL RNA qPCR assay for parasite detection in laboratory-reared and field-collected sand flies and reservoir hosts. Parasit Vectors 2020; 13:276. [PMID: 32487217 PMCID: PMC7268266 DOI: 10.1186/s13071-020-04141-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 05/21/2020] [Indexed: 11/15/2022] Open
Abstract
Background In eco-epidemiological studies, Leishmania detection in vectors and reservoirs is frequently accomplished by high-throughput and sensitive molecular methods that target minicircle kinetoplast DNA (kDNA). A pan-Leishmania SYBR green quantitative PCR (qPCR) assay which detects the conserved spliced-leader RNA (SL RNA) sequence was developed recently. This study assessed the SL RNA assay performance combined with a crude extraction method for the detection of Leishmania in field-collected and laboratory-reared sand flies and in tissue samples from hyraxes as reservoir hosts. Methods Field-collected and laboratory-infected sand fly and hyrax extracts were subjected to three different qPCR approaches to assess the suitability of the SL RNA target for Leishmania detection. Nucleic acids of experimentally infected sand flies were isolated with a crude extraction buffer with ethanol precipitation and a commercial kit and tested for downstream DNA and RNA detection. Promastigotes were isolated from culture and sand fly midguts to assess whether there was difference in SL RNA and kDNA copy numbers. Naive sand flies were spiked with a serial dilution of promastigotes to make a standard curve. Results The qPCR targeting SL RNA performed well on infected sand fly samples, despite preservation and extraction under presumed unfavorable conditions for downstream RNA detection. Nucleic acid extraction by a crude extraction buffer combined with a precipitation step was highly compatible with downstream SL RNA and kDNA detection. Copy numbers of kDNA were found to be identical in culture-derived parasites and promastigotes isolated from sand fly midguts. SL RNA levels were slightly lower in sand fly promastigotes (ΔCq 1.7). The theoretical limit of detection and quantification of the SL RNA qPCR respectively reached down to 10−3 and 10 parasite equivalents. SL RNA detection in stored hyrax samples was less efficient with some false-negative assay results, most likely due to the long-term tissue storage in absence of RNA stabilizing reagents. Conclusions This study shows that a crude extraction method in combination with the SL RNA qPCR assay is suitable for the detection and quantification of Leishmania in sand flies. The assay is inexpensive, sensitive and pan-Leishmania specific, and accordingly an excellent assay for high-throughput screening in entomological research.![]()
Collapse
Affiliation(s)
- Myrthe Pareyn
- Evolutionary Ecology Group, University of Antwerp, Wilrijk, Belgium.
| | - Rik Hendrickx
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Nigatu Girma
- Biology Department, Arba Minch University, Arba Minch, Ethiopia
| | - Sarah Hendrickx
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Lieselotte Van Bockstal
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | | | - Simon Shibru
- Biology Department, Arba Minch University, Arba Minch, Ethiopia
| | - Louis Maes
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Herwig Leirs
- Evolutionary Ecology Group, University of Antwerp, Wilrijk, Belgium
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium.
| |
Collapse
|
5
|
Eberhardt E, Hendrickx R, Van den Kerkhof M, Monnerat S, Alves F, Hendrickx S, Maes L, Caljon G. Comparative evaluation of nucleic acid stabilizing reagents for RNA- and DNA-based Leishmania detection in blood as proxy for visceral burdens. J Microbiol Methods 2020; 173:105935. [PMID: 32376283 DOI: 10.1016/j.mimet.2020.105935] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/23/2020] [Accepted: 04/23/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND Molecular detection techniques using peripheral blood are preferred over invasive tissue aspiration for the diagnosis and post-treatment follow-up of visceral leishmaniasis (VL) patients. This study aims to identify suitable stabilizing reagents to prevent DNA and RNA degradation during storage and transport to specialized laboratories where molecular diagnosis is performed. METHODOLOGY The stabilizing capacities of different commercially available reagents were compared using promastigote-spiked human blood and peripheral blood of Syrian golden hamsters subjected to experimental infection, treatment (miltefosine or aminopyrazole DNDi-1044) and immunosuppression. The impact of various storage temperature conditions was tested in combination with an established kinetoplast DNA (kDNA) qPCR and a recently developed spliced leader RNA (SL-RNA) assay for Leishmania detection. PRINCIPAL FINDINGS Irrespective of the blood type and stabilizer used, threshold (cT) values obtained with the SL-RNA qPCR were systematically lower than those obtained with the kDNA assay, confirming the advantage of the SL-RNA assay over the widely used kDNA assay for low-level Leishmania detection. Peripheral blood parasite levels correlated relatively well with hepatic burdens. RNA protect cell reagent provided the most optimal simultaneous DNA and RNA stabilization in both human and hamster blood. However, this stabilizer requires an erythrocyte lysis step, which can be challenging under field conditions. DNA/RNA shield provides a good alternative for downstream kDNA and SL-RNA assays, especially if sample storage capacity at 4 °C can be guaranteed. CONCLUSIONS/SIGNIFICANCE The recommended stabilizing reagents are compatible with RNA- and DNA-based Leishmania detection in peripheral blood in the VL hamster model and spiked human blood. Since molecular detection techniques using peripheral blood are less invasive than microscopic assessment of tissue aspirates, the findings of this study may be applied to human VL clinical studies.
Collapse
Affiliation(s)
- Eline Eberhardt
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Wilrijk, Belgium
| | - Rik Hendrickx
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Wilrijk, Belgium
| | - Magali Van den Kerkhof
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Wilrijk, Belgium
| | | | - Fabiana Alves
- Drugs for Neglected Disease initiative (DNDi), Geneva, Switzerland
| | - Sarah Hendrickx
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Wilrijk, Belgium
| | - Louis Maes
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Wilrijk, Belgium
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Wilrijk, Belgium.
| |
Collapse
|
6
|
Eberhardt E, Van den Kerkhof M, Bulté D, Mabille D, Van Bockstal L, Monnerat S, Alves F, Mbui J, Delputte P, Cos P, Hendrickx S, Maes L, Caljon G. Evaluation of a Pan-Leishmania Spliced-Leader RNA Detection Method in Human Blood and Experimentally Infected Syrian Golden Hamsters. J Mol Diagn 2018; 20:253-263. [PMID: 29355825 DOI: 10.1016/j.jmoldx.2017.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 11/24/2017] [Accepted: 12/11/2017] [Indexed: 10/18/2022] Open
Abstract
Several methods have been developed for the detection of Leishmania, mostly targeting the minicircle kinetoplast DNA (kDNA). A new RNA real-time quantitative PCR (qPCR) assay was developed targeting the conserved and highly expressed spliced-leader (SL) mini-exon sequence. This study compared the limits of detection of various real-time PCR assays in hamsters infected with Leishmania infantum, in spiked human blood, and in clinical blood samples from visceral leishmaniasis patients. The SL-RNA assay showed an excellent analytical sensitivity in tissues (0.005 and 0.002 parasites per mg liver and spleen, respectively) and was not prone to false-positive reactions. Evaluation of the SL-RNA assay on clinical samples demonstrated lower threshold cycle values than the kDNA qPCR, an excellent interrun stability of 97%, a 93% agreement with the kDNA assay, and an estimated sensitivity, specificity, and accuracy of 93.2%, 94.3%, and 93.8%, respectively. The SL-RNA qPCR assay was equally efficient for detecting Leishmania major, Leishmania tropica, Leishmania mexicana, Leishmania guayensis, Leishmania panamensis, Leishmania braziliensis, L. infantum, and Leishmania donovani and revealed similar SL-RNA levels in the different species and the occurrence of polycistronic SL-containing transcripts in Viannia species. Collectively, this single SL-RNA qPCR assay enables universal Leishmania detection and represents a particularly useful addition to the widely used kDNA assay in clinical studies in which the detection of viable parasites is pivotal to assess parasitological cure.
Collapse
Affiliation(s)
- Eline Eberhardt
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Magali Van den Kerkhof
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Dimitri Bulté
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Dorien Mabille
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Lieselotte Van Bockstal
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | | | - Fabiana Alves
- Drugs for Neglected Disease Initiative, Geneva, Switzerland
| | - Jane Mbui
- Centre for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - Peter Delputte
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Paul Cos
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Sarah Hendrickx
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Louis Maes
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium.
| |
Collapse
|
7
|
van den Bogaart E, Mens PF, Adams ER, Grobusch MP, Schallig HDFH. Phagocytosis of hemozoin by RAW 264.7 cells, but not THP-1 cells, promotes infection by Leishmania donovani with a nitric oxide-independent mechanism. Parasitol Int 2016; 66:196-206. [PMID: 27623326 DOI: 10.1016/j.parint.2016.09.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 08/19/2016] [Accepted: 09/08/2016] [Indexed: 01/28/2023]
Abstract
During its intra-erythrocytic development, the malaria parasite Plasmodium falciparum synthesizes insoluble hemozoin (HZ) crystals that are released into the circulation upon rupture of parasitized red blood cells, and rapidly phagocytized by host mononuclear cells. Here, HZ persists undigested, causing functional impairment and possibly leading to increased host susceptibility to secondary infections. In patients with malaria and visceral leishmaniasis (VL) co-infections, HZ-loaded macrophages are likely to co-harbor Leishmania donovani parasites, but whether this might influence the course of the Leishmania infection is unknown. In this study, L. donovani amastigote growth was monitored in mouse RAW 264.7 macrophages and PMA-differentiated THP-1 cells previously exposed to increasing amounts of HZ or its synthetic analogue β-hematin (BH). Latex beads were used as a phagocytic control. Data demonstrate that phagocytosis of HZ and BH by RAW 264.7 cells promoted infection therein by L. donovani parasites in a dose-dependent fashion. Similar results were not observed when using THP-1 cells, despite a clear persistence of undigested heme up to 48h after phagocytosis. Conditioning with lipopolysaccharide (LPS)/interferon (IFN)-γ prior to Leishmania infection triggered the release in RAW 264.7 cells of nitric oxide (NO), a highly leishmanicidal metabolite. However, neither HZ nor BH pre-ingestion were able to inhibit NO production following stimulation with LPS/IFN-γ, suggesting that the HZ- and BH-promoting effect on L. donovani infection occurred with an NO-independent mechanism. In conclusion, these preliminary findings highlight a possible detrimental effect of HZ on the course of VL, warranting further investigation into the clinical relevance of the current models.
Collapse
Affiliation(s)
- Erika van den Bogaart
- Parasitology Unit, Department of Biomedical Research, Royal Tropical Institute (KIT), Meibergdreef 39, 1105 AZ Amsterdam, The Netherlands.
| | - Pètra F Mens
- Parasitology Unit, Department of Medical Microbiology, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Emily R Adams
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Pl, Liverpool, Merseyside L3 5QA, United Kingdom
| | - Martin P Grobusch
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Henk D F H Schallig
- Parasitology Unit, Department of Medical Microbiology, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| |
Collapse
|
8
|
Eberhardt E, Mondelaers A, Hendrickx S, Van den Kerkhof M, Maes L, Caljon G. Molecular detection of infection homogeneity and impact of miltefosine treatment in a Syrian golden hamster model of Leishmania donovani and L. infantum visceral leishmaniasis. Parasitol Res 2016; 115:4061-70. [PMID: 27412759 DOI: 10.1007/s00436-016-5179-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 06/20/2016] [Indexed: 02/07/2023]
Abstract
Control of visceral leishmaniasis caused by Leishmania infantum and Leishmania donovani primarily relies on chemotherapy using an increasingly compromised repertoire of antileishmanial compounds. For evaluation of novel drugs, the Syrian golden hamster is considered as a clinically relevant laboratory model. In this study, two molecular parasite detection assays were developed targeting cathepsin-like cysteine protease B (CPB) DNA and 18S rRNA to achieve absolute amastigote quantification in the major target organs liver and spleen. Both quantitative PCR (qPCR) techniques showed excellent agreement with a strong correlation with the conventional microscopic reading of Giemsa-stained tissue smears. Using multiple single tissue pieces and all three detection methods, we confirmed homogeneity of infection in liver and spleen and the robustness of extrapolating whole organ burdens from a small single tissue piece. Comparison of pre- and post-treatment burdens in infected hamsters using the three detection methods consistently revealed a stronger parasite reduction in the spleen compared to the liver, indicating an organ-dependent clearance efficacy for miltefosine. In conclusion, this study in the hamster demonstrated high homogeneity of infection in liver and spleen and advocates the use of molecular detection methods for assessment of low (post-treatment) tissue burdens.
Collapse
Affiliation(s)
- Eline Eberhardt
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Room S7.24, Campus Drie Eiken, Universiteitsplein 1, B-2610, Wilrijk, Belgium
| | - Annelies Mondelaers
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Room S7.24, Campus Drie Eiken, Universiteitsplein 1, B-2610, Wilrijk, Belgium
| | - Sarah Hendrickx
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Room S7.24, Campus Drie Eiken, Universiteitsplein 1, B-2610, Wilrijk, Belgium
| | - Magali Van den Kerkhof
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Room S7.24, Campus Drie Eiken, Universiteitsplein 1, B-2610, Wilrijk, Belgium
| | - Louis Maes
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Room S7.24, Campus Drie Eiken, Universiteitsplein 1, B-2610, Wilrijk, Belgium
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Room S7.24, Campus Drie Eiken, Universiteitsplein 1, B-2610, Wilrijk, Belgium.
| |
Collapse
|
9
|
Gomes CM, Mazin SC, Santos ERD, Cesetti MV, Bächtold GAB, Cordeiro JHDF, Theodoro FCET, Damasco FDS, Carranza SAV, Santos ADO, Roselino AM, Sampaio RNR. Accuracy of mucocutaneous leishmaniasis diagnosis using polymerase chain reaction: systematic literature review and meta-analysis. Mem Inst Oswaldo Cruz 2015; 110:157-65. [PMID: 25946238 PMCID: PMC4489445 DOI: 10.1590/0074-02760140280] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Accepted: 02/10/2015] [Indexed: 11/22/2022] Open
Abstract
The diagnosis of mucocutaneous leishmaniasis (MCL) is hampered by the absence of a
gold standard. An accurate diagnosis is essential because of the high toxicity of the
medications for the disease. This study aimed to assess the ability of polymerase
chain reaction (PCR) to identify MCL and to compare these results with clinical
research recently published by the authors. A systematic literature review based on
the Preferred Reporting Items for Systematic Reviews and Meta-Analyses: the PRISMA
Statement was performed using comprehensive search criteria and communication with
the authors. A meta-analysis considering the estimates of the univariate and
bivariate models was performed. Specificity near 100% was common among the papers.
The primary reason for accuracy differences was sensitivity. The meta-analysis, which
was only possible for PCR samples of lesion fragments, revealed a sensitivity of 71%
[95% confidence interval (CI) = 0.59; 0.81] and a specificity of 93% (95% CI = 0.83;
0.98) in the bivariate model. The search for measures that could increase the
sensitivity of PCR should be encouraged. The quality of the collected material and
the optimisation of the amplification of genetic material should be prioritised.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Ana Maria Roselino
- Hospital das Clínicas, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil
| | | |
Collapse
|
10
|
Sacks DL, Melby PC. Animal models for the analysis of immune responses to leishmaniasis. ACTA ACUST UNITED AC 2015; 108:19.2.1-19.2.24. [PMID: 25640990 DOI: 10.1002/0471142735.im1902s108] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This unit focuses on the murine model of cutaneous leishmaniasis and models of visceral leishmaniasis in mice and hamsters. Each basic protocol describes the methods used to inoculate parasites and to evaluate infections with regard to lesion progression and visceralization, and quantification of parasite load.
Collapse
Affiliation(s)
- David L Sacks
- National Institute of Allergy & Infectious Diseases, Bethesda, Maryland
| | - Peter C Melby
- University of Texas Medical Branch (UTMB), Galveston, Texas
| |
Collapse
|
11
|
A quantitative reverse-transcriptase PCR assay for the assessment of drug activities against intracellular Theileria annulata schizonts. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2014; 4:201-9. [PMID: 25516828 PMCID: PMC4266814 DOI: 10.1016/j.ijpddr.2014.09.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 09/01/2014] [Accepted: 09/04/2014] [Indexed: 12/15/2022]
Abstract
Quantitative RT real time PCR was used to assess metabolic impairment of Theileria schizonts. The method was validated with buparvaquone. Buparvaquone acts directly and rapidly on the parasite within 1 h of treatment. Electron microscopy confirmed these findings. A series of anti-parasitic compounds and antibiotics acted primarily on the host cells.
Intracellular schizonts of the apicomplexans Theileria annulata and Theileria parva immortalize bovine leucocytes thereby causing fatal immunoproliferative diseases. Buparvaquone, a hydroxynaphthoquinone related to parvaquone, is the only drug available against Theileria. The drug is only effective at the onset of infection and emerging resistance underlines the need for identifying alternative compounds. Current drug assays employ monitoring of proliferation of infected cells, with apoptosis of the infected host cell as a read-out, but it is often unclear whether active compounds directly impair the viability of the parasite or primarily induce host cell death. We here report on the development of a quantitative reverse transcriptase real time PCR method based on two Theileria genes, tasp and tap104, which are both expressed in schizonts. Upon in vitro treatment of T. annulata infected bovine monocytes with buparvaquone, TaSP and Tap104 mRNA expression levels significantly decreased in relation to host cell actin already within 4 h of drug exposure, while significant differences in host cell proliferation were detectable only after 48–72 h. TEM revealed marked alterations of the schizont ultrastructure already after 2 h of buparvaquone treatment, while the host cell remained unaffected. Expression of TaSP and Tap104 proteins showed a marked decrease only after 24 h. Therefore, the analysis of expression levels of mRNA coding for TaSP and Tap104 allows to directly measuring impairment of parasite viability. We subsequently applied this method using a series of compounds affecting different targets in other apicomplexan parasites, and show that monitoring of TaSP- and Tap104 mRNA levels constitutes a suitable tool for anti-theilerial drug development.
Collapse
|
12
|
Sacks DL, Melby PC. Animal models for the analysis of immune responses to leishmaniasis. CURRENT PROTOCOLS IN IMMUNOLOGY 2001; Chapter 19:Unit 19.2. [PMID: 18432753 PMCID: PMC4363783 DOI: 10.1002/0471142735.im1902s28] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This unit focuses on the murine model of cutaneous leishmaniasis and models of visceral leishmaniasis in mice and hamsters. Each basic protocol describes the methods used to inoculate parasites and to evaluate infections with regard to lesion progression and visceralization, and quantification of parasite load. Five support protocols are provided; two for the growth and isolation of metacyclic promastigotes from in vitro culture, one for isolation of tissue amastigotes from infected animals, one for cryopreservation of parasites, and one for the preparation of blood agar plates for quantitation of parasite numbers in infected tissue.
Collapse
Affiliation(s)
- D L Sacks
- National Institute of Allergy & Infectious, Diseases, Bethesda, Maryland, USA
| | | |
Collapse
|