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De Silva NL, De Silva VNH, Weerasooriya MV, Takagi H, Itoh M, Kato H, Yahathugoda TC. A real-time PCR for quantification of parasite burden and its correlations with clinical characteristics and anti-rKRP42 IgG level in cutaneous leishmaniasis in Sri Lanka. Parasitol Int 2024; 100:102865. [PMID: 38341021 DOI: 10.1016/j.parint.2024.102865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024]
Abstract
In visceral and mucocutaneous leishmaniasis, humoral immune response can reflect disease severity and parasite burden. Cutaneous leishmaniasis (CL) in Sri Lanka is caused by a usually visceralizing parasite, Leishmania donovani. We assessed the parasite burden (relative quantity-RQ) in 190 CL patients using quantitative real-time PCR (qPCR-with primers designed for this study) and smear microscopy, then correlated it with clinical parameters and IgG response. RQ of parasite DNA was determined with human-specific glyceraldehyde 3-phosphate dehydrogenase (GAPDH) as the internal control. The qPCR sensitivity was tested with serially diluted DNA from cultured L. donovani parasites. Smears were assigned a score based on number of parasites per high power field. Data from previous studies were used for comparison and correlation; nested Internal Transcribed Spacer 1 (ITS1) PCR as reference standard (RS) and IgG antibody titers to the Leishmania rKRp42 antigen as the immune response. The qPCR amplified and quantified 86.8% of the samples while demonstrating a fair and significant agreement with ITS1-PCR and microscopy. Parasite burden by qPCR and microscopy were highly correlated (r = 0.76; p = 0.01) but showed no correlation with the IgG response (r = 0.056; p = 0.48). Corresponding mean RQs of IgG titers grouped by percentiles, showed no significant difference (p = 0.93). Mean RQ was higher in early lesions (p = 0.04), decreased with lesion size (p = 0.12) and slightly higher among papules, nodules and wet ulcers (p = 0.72). Our study established qPCR's efficacy in quantifying parasite burden in Sri Lankan CL lesions but no significant correlation was observed between the parasite burden and host IgG response to the Leishmania rKRP42 antigen.
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Affiliation(s)
| | | | | | - Hidekazu Takagi
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Aichi 480-1195, Japan.
| | - Makoto Itoh
- Department of Microbiology and Immunology, Aichi Medical University School of Medicine, Aichi 480-1195, Japan
| | - Hirotomo Kato
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Tochigi 329-0498, Japan.
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Cavender W, Swan C, Wolf S, Van Vliet D, Johnson AA, Forest A, Shields R, Loch T, Knupp C, Drennan J, Glenney G, Hallett SL, Marcino J, Reed A. Comparative evaluation of three real-time polymerase chain reaction assays to detect Myxobolus cerebralis. JOURNAL OF AQUATIC ANIMAL HEALTH 2024. [PMID: 38622805 DOI: 10.1002/aah.10220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 03/05/2024] [Accepted: 03/06/2024] [Indexed: 04/17/2024]
Abstract
OBJECTIVE We sought to evaluate accurate and reproducible detection of Myxobolus cerebralis (Mc), the causative agent of whirling disease, by using nested polymerase chain reaction (nPCR) and three previously established real-time quantitative PCR (qPCR) assays: K18S (Kelley 18S), C18S (Cavender 18S), and Hsp70 (heat shock protein 70). We used a "fit for purpose" approach combined with intra- and interlaboratory testing to identify a molecular testing method that would be equivalent to the currently accepted nPCR procedure for Mc. METHODS Assay performance was compared using a combination of intra- and interlaboratory testing that used synthetic gBlocks along with naturally and experimentally infected fish tissue. North American isolates representing geographically distinct locations were also tested using all three assays. RESULT The K18S and C18S assays exhibited high assay sensitivity, intra- and interlaboratory repeatability of sample replicates, and reproducible identification of all test samples across multiple laboratories. In contrast, the Hsp70 assay failed to detect several positive samples at low DNA concentrations during intra- and interlaboratory testing. The K18S assay was the only procedure that demonstrated perfect detection accuracy when testing geographically distinct Mc isolates. Results demonstrated the K18S assay is robust under variable test conditions, is more accurate than the C18S and Hsp70 assays, and provides detection capabilities equivalent to those of the currently accepted nPCR confirmation assay "gold standard" that is described in the American Fisheries Society-Fish Health Section (AFS-FHS) Blue Book. CONCLUSION The "fit for purpose" approach and preliminary completion of the World Organization for Animal Health validation pathway demonstrate that the K18S assay provides an alternate method for Mc testing. This work provides the foundation for acceptance of the K18S assay into the AFS-FHS Blue Book as a standardized test procedure for Mc.
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Affiliation(s)
- Wade Cavender
- Utah Division of Wildlife Resources, Aquatic Animal Health and Research Center, Logan, Utah, USA
| | - Christine Swan
- Utah Division of Wildlife Resources, Aquatic Animal Health and Research Center, Logan, Utah, USA
| | - Skylar Wolf
- Utah Division of Wildlife Resources, Aquatic Animal Health and Research Center, Logan, Utah, USA
| | - Danielle Van Vliet
- Utah Division of Wildlife Resources, Aquatic Animal Health and Research Center, Logan, Utah, USA
| | - Alison Aceves Johnson
- Utah Division of Wildlife Resources, Aquatic Animal Health and Research Center, Logan, Utah, USA
| | - Anna Forest
- Utah Division of Wildlife Resources, Aquatic Animal Health and Research Center, Logan, Utah, USA
| | - Robert Shields
- Utah Division of Wildlife Resources, Aquatic Animal Health and Research Center, Logan, Utah, USA
| | - Thomas Loch
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, USA
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, Michigan, USA
| | - Christopher Knupp
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, Michigan, USA
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, Michigan, USA
| | - John Drennan
- Colorado Parks and Wildlife, Aquatic Animal Health Laboratory, Brush, Colorado, USA
| | - Gavin Glenney
- U.S. Fish and Wildlife Service, Lamar Fish Health Center, Lamar, Pennsylvania, USA
| | - Sascha L Hallett
- Department of Microbiology, Oregon State University, Corvallis, Oregon, USA
| | - Joe Marcino
- Arizona Game and Fish Department, Fish Health Laboratory, Phoenix, Arizona, USA
| | - Aimee Reed
- Oregon Department of Fish and Wildlife, Fish Health Services, Corvallis, Oregon, USA
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Amaro F, Vilares A, Martins S, Reis T, Osório HC, Alves MJ, Gargaté MJ. Co-Circulation of Leishmania Parasites and Phleboviruses in a Population of Sand Flies Collected in the South of Portugal. Trop Med Infect Dis 2023; 9:3. [PMID: 38276633 PMCID: PMC10821132 DOI: 10.3390/tropicalmed9010003] [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: 11/21/2023] [Revised: 12/15/2023] [Accepted: 12/18/2023] [Indexed: 01/27/2024] Open
Abstract
In the Old World, phlebotomine sand flies from the genus Phlebotomus are implicated in the transmission of Leishmania spp. parasites (Kinetoplastida: Trypanosomatidae) and viruses belonging to the genus Phlebovirus (Bunyavirales: Phenuiviridae). Two of the five sand fly species known to occur in Portugal, Phlebotomus perniciosus and Ph. ariasi, the former being the most ubiquitous, are recognized vectors of Leishmania infantum, which causes visceral leishmaniasis, the most prevalent form of leishmaniasis in the country. Phlebotomus perniciosus is also the vector of the neurotropic Toscana virus, which can cause aseptic meningitis. Entomological surveillance is essential to provide fundamental data about the presence of vectors and the pathogens they can carry. As such, and given the lack of data in Portugal, an entomological survey took place in the Algarve, the southernmost region of the country, from May to October 2018. Polymerase chain reaction assays were performed in order to detect the presence of the above-mentioned pathogens in sand fly pools. Not only were both Leishmania parasites and phleboviruses detected during this study, but more importantly, it was the first time their co-circulation was verified in the same sand fly population collected in Portugal.
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Affiliation(s)
- Fátima Amaro
- Centre for Vectors and Infectious Diseases Research, National Institute of Health Doutor Ricardo Jorge, No. 5, 2965-575 Águas de Moura, Portugal; (H.C.O.); (M.J.A.)
- Environment and Infectious Diseases Research Group, Environmental Health Institute, 1649-028 Lisboa, Portugal
- Centre for Animal Science Studies (CECA), University of Porto, 4050-453 Porto, Portugal
| | - Anabela Vilares
- National Reference Laboratory of Parasitic and Fungal Infections, National Institute of Health Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal; (A.V.); (S.M.); (T.R.); (M.J.G.)
| | - Susana Martins
- National Reference Laboratory of Parasitic and Fungal Infections, National Institute of Health Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal; (A.V.); (S.M.); (T.R.); (M.J.G.)
| | - Tânia Reis
- National Reference Laboratory of Parasitic and Fungal Infections, National Institute of Health Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal; (A.V.); (S.M.); (T.R.); (M.J.G.)
| | - Hugo Costa Osório
- Centre for Vectors and Infectious Diseases Research, National Institute of Health Doutor Ricardo Jorge, No. 5, 2965-575 Águas de Moura, Portugal; (H.C.O.); (M.J.A.)
- Environment and Infectious Diseases Research Group, Environmental Health Institute, 1649-028 Lisboa, Portugal
| | - Maria João Alves
- Centre for Vectors and Infectious Diseases Research, National Institute of Health Doutor Ricardo Jorge, No. 5, 2965-575 Águas de Moura, Portugal; (H.C.O.); (M.J.A.)
- Environment and Infectious Diseases Research Group, Environmental Health Institute, 1649-028 Lisboa, Portugal
- Centre for Animal Science Studies (CECA), University of Porto, 4050-453 Porto, Portugal
| | - Maria João Gargaté
- National Reference Laboratory of Parasitic and Fungal Infections, National Institute of Health Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal; (A.V.); (S.M.); (T.R.); (M.J.G.)
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Patiño LH, Ballesteros N, Muñoz M, Jaimes J, Castillo-Castañeda AC, Madigan R, Paniz-Mondolfi A, Ramírez JD. Validation of Oxford nanopore sequencing for improved New World Leishmania species identification via analysis of 70-kDA heat shock protein. Parasit Vectors 2023; 16:458. [PMID: 38111024 PMCID: PMC10726620 DOI: 10.1186/s13071-023-06073-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 11/29/2023] [Indexed: 12/20/2023] Open
Abstract
BACKGROUND Leishmaniasis is a parasitic disease caused by obligate intracellular protozoa of the genus Leishmania. This infection is characterized by a wide range of clinical manifestations, with symptoms greatly dependent on the causal parasitic species. Here we present the design and application of a new 70-kDa heat shock protein gene (hsp70)-based marker of 771 bp (HSP70-Long). We evaluated its sensitivity, specificity and diagnostic performance employing an amplicon-based MinION™ DNA sequencing assay to identify different Leishmania species in clinical samples from humans and reservoirs with cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL). We also conducted a comparative analysis between our novel marker and a previously published HSP70 marker known as HSP70-Short, which spans 330 bp. METHODS A dataset of 27 samples from Colombia, Venezuela and the USA was assembled, of which 26 samples were collected from humans, dogs and cats affected by CL and one sample was collected from a dog with VL in the USA (but originally from Greece). DNA was extracted from each sample and underwent conventional PCR amplification utilizing two distinct HSP70 markers: HSP70-Short and HSP70-Long. The subsequent products were then sequenced using the MinION™ sequencing platform. RESULTS The results highlight the distinct characteristics of the newly devised HSP70-Long primer, showcasing the notable specificity of this primer, although its sensitivity is lower than that of the HSP70-Short marker. Notably, both markers demonstrated strong discriminatory capabilities, not only in distinguishing between different species within the Leishmania genus but also in identifying instances of coinfection. CONCLUSIONS This study underscores the outstanding specificity and effectiveness of HSP70-based MinION™ sequencing, in successfully discriminating between diverse Leishmania species and identifying coinfection events within samples sourced from leishmaniasis cases.
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Affiliation(s)
- Luz Helena Patiño
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Nathalia Ballesteros
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Marina Muñoz
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Jesús Jaimes
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Adriana C Castillo-Castañeda
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Roy Madigan
- Animal Hospital of Smithson Valley, 286 Singing Oaks, Ste 113, Spring Branch, TX, 78070, USA
| | - Alberto Paniz-Mondolfi
- Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Juan David Ramírez
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia.
- Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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Pasquier G, Andreotti Q, Ravel C, Sterkers Y. Molecular diagnosis of visceral leishmaniasis: a French study comparing a reference PCR method targeting kinetoplast DNA and a commercial kit targeting ribosomal DNA. Microbiol Spectr 2023; 11:e0215423. [PMID: 37819127 PMCID: PMC10714885 DOI: 10.1128/spectrum.02154-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 08/23/2023] [Indexed: 10/13/2023] Open
Abstract
IMPORTANCE PCR revolutionized the direct diagnosis of infectious diseases, especially protozooses, where the infectious load is usually low. Commercial PCR methods are available and offer many advantages, including convenience and batch tracking as part of a quality system. For most parameters, the performance of commercial methods is at least as good as that of finely optimized methods developed in expert laboratories. This comparison work has not been done for the molecular diagnosis of visceral leishmaniasis. Leishmania sp. has a unique organelle, the kinetoplast, which corresponds to the mitochondrial DNA. It is organized into a large number of minicircles, which has made it a target for the development of diagnostic PCR. The quanty Leishmaniae, Clonit kit targeting ribosomal DNA was compared to a widely used laboratory-developed method based on kinetoplast DNA. This reference method gave significantly better results, probably due to the difference in the number of repeats of the PCR targets.
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Affiliation(s)
- Grégoire Pasquier
- Department of Parasitology-Mycology, National Reference Center for Leishmaniasis, University of Montpellier, CNRS, IRD, University Hospital Center (CHU) of Montpellier, Montpellier, France
| | - Quentin Andreotti
- Department of Parasitology-Mycology, National Reference Center for Leishmaniasis, University of Montpellier, CNRS, IRD, University Hospital Center (CHU) of Montpellier, Montpellier, France
| | - Christophe Ravel
- Department of Parasitology-Mycology, National Reference Center for Leishmaniasis, University of Montpellier, CNRS, IRD, University Hospital Center (CHU) of Montpellier, Montpellier, France
| | - Yvon Sterkers
- Department of Parasitology-Mycology, National Reference Center for Leishmaniasis, University of Montpellier, CNRS, IRD, University Hospital Center (CHU) of Montpellier, Montpellier, France
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6
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Ramírez JD, Cao L, Castillo-Castañeda AC, Patino LH, Ayala MS, Cordon-Cardo C, Sordillo EM, Paniz-Mondolfi A. Clinical performance of a quantitative pan-genus Leishmania Real-time PCR assay for diagnosis of cutaneous and visceral leishmaniasis. Pract Lab Med 2023; 37:e00341. [PMID: 37842331 PMCID: PMC10570565 DOI: 10.1016/j.plabm.2023.e00341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 09/20/2023] [Accepted: 10/04/2023] [Indexed: 10/17/2023] Open
Abstract
Leishmaniasis is a complex vector-borne disease caused by various Leishmania species, affecting humans and animals. Current diagnostic methods have limitations, leading to potential misdiagnosis. Therefore, there is an urgent need for specific and sensitive diagnostic tools. We evaluated the sensitivity of a quantitative real-time PCR (qPCR) assay targeting the 18S gene in diverse clinical sample matrices. The assay showed a wide dynamic range and a limit of detection (LoD) of 1 parasite equivalent per milliliter (eq-p/mL) for all tested species. It exhibited high specificity for Leishmania DNA, with no amplification against other microorganisms. When applied to samples from patients with visceral and cutaneous leishmaniasis, the qPCR assay provided results that matched the reference methods and allowed estimation of parasite burdens. This assay holds promise for diagnosing and monitoring leishmaniasis by offering high sensitivity, specificity, and the ability to estimate parasitemia. Further studies are needed to enhance Leishmania molecular diagnostics and expand their coverage for improved clinical impact.
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Affiliation(s)
- Juan David Ramírez
- Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Liyong Cao
- Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Adriana C. Castillo-Castañeda
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Luz Helena Patino
- Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Martha S. Ayala
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Carlos Cordon-Cardo
- Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Emilia Mia Sordillo
- Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Alberto Paniz-Mondolfi
- Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Instituto de Investigaciones Biomédicas IDB/Incubadora Venezolana de la Ciencia, Barquisimeto, Venezuela
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Jaimes-Dueñez J, Castillo-Castañeda A, Jiménez-Leaño Á, Duque JE, Cantillo-Barraza O, Cáceres-Rivera DI, Granada Y, Triana-Chávez O, Ramírez JD. Epidemiological features of Leishmania infantum in dogs (Canis lupus familiaris) suggest a latent risk of visceral leishmaniasis in the metropolitan area of Bucaramanga, Santander, Eastern Colombia. Prev Vet Med 2023; 219:106021. [PMID: 37738753 DOI: 10.1016/j.prevetmed.2023.106021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/24/2023] [Accepted: 09/04/2023] [Indexed: 09/24/2023]
Abstract
Visceral leishmaniasis (VL) is a disease caused by species of the Leishmania donovani complex that is mainly transmitted through the urban cycle involving dogs as the primary reservoir. In Colombia, the incidence of VL is increasing, along with the spread of potential vectors. This study aims to investigate the eco-epidemiological factors associated with Leishmania spp. infection in dogs from the Metropolitan Area of Bucaramanga (MAB), Santander, eastern Colombia, which is a region at risk for VL. We conducted molecular and serological surveillance of Leishmania spp. in 207 dogs from MAB to determine the epidemiological factors associated with infection. Subsequently, we carried out a molecular and serological analysis of phlebotomine and humans, respectively, in areas with a higher prevalence of infection, aiming to describe the main features associated with the transmission cycle. Out of the 207 dogs tested, 37 (17.8%, 95% CI = 12.6-23.1%) were positive for the presence of Leishmania antibodies by the IFAT test, and only 9 (4.3%, 95% CI = 1.55-7.15%) were positive for L. infantum by PCR. Multivariate analyses indicated that canine shelters and dogs with clinical signs commonly associated with canine VL had a higher prevalence of infection (P < 0.05). In the entomological survey, 69 blood-fed female phlebotomine of the genus Lutzomyia were captured in canine shelters, among them, 55% were identified as Lutzomyia camposi, 29% as Lu. ovallesi, 7% as Lu. dubitans, 6% as Lu. torvida, and 3% as Lu. cayennensis. The identified meal sources of the phlebotomine included human, pig, avian, cattle, and porcupine (Coendou quichua) blood. However, no phlebotomine positive for Leishmania spp. were detected by molecular analyses. Finally, 14 humans who had frequent contact with L. infantum-positive dogs were analyzed through rK39 test, but none tested was positive for IgG/IgM antibodies. The molecular and serological analyses indicate the circulation of L. infantum in dogs from MAB, with canine shelters having the highest prevalence of infection. The entomological survey of canine shelters showed a significant diversity of phlebotomine without potential vectors of L. infantum, suggesting the presence of infection in dogs from these areas could take place in other locations or through other transmission routes. The circulation of L. infantum in multiple dogs from MAB suggests a latent risk of zoonotic transmission of VL in these cities.
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Affiliation(s)
- Jeiczon Jaimes-Dueñez
- Grupo de Investigación en Ciencias Animales GRICA, Facultad de Medicina Veterinaria y Zootecnia, Universidad Cooperativa de Colombia UCC, Bucaramanga, Colombia.
| | - Adriana Castillo-Castañeda
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Ángela Jiménez-Leaño
- Grupo de Investigación en Ciencias Animales GRICA, Facultad de Medicina Veterinaria y Zootecnia, Universidad Cooperativa de Colombia UCC, Bucaramanga, Colombia
| | - Jonny E Duque
- Centro de Investigaciones en Enfermedades Tropicales, CINTROP, Facultad de Medicina, Universidad Industrial de Santander, Bucaramanga, Colombia
| | - Omar Cantillo-Barraza
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
| | - Diana Isabel Cáceres-Rivera
- Grupo de Investigación para el fortalecimiento de la salud y el bienestar GIFOSABI, Facultad de Enfermería, Universidad Cooperativa de Colombia UCC, Bucaramanga, Colombia
| | - Yurany Granada
- Grupo Biología y Control de Enfermedades Infecciosas, BCEI, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia, Medellín, Colombia
| | - Omar Triana-Chávez
- Grupo Biología y Control de Enfermedades Infecciosas, BCEI, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia, Medellín, Colombia
| | - Juan David Ramírez
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia; Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai, New York city, NY, USA
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Filgueira CPB, Pitta-Pereira D, Cantanhêde LM, Ferreira GEM, Dos Reis S, Cupolillo E, Moreira OC, Britto C, Boité MC. HRM Accuracy and Limitations as a Species Typing Tool for Leishmania Parasites. Int J Mol Sci 2023; 24:14784. [PMID: 37834232 PMCID: PMC10573552 DOI: 10.3390/ijms241914784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 09/19/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023] Open
Abstract
High Resolution Melting Analysis (HRM) has been pointed out as a suitable alternative method to detect and identify Leishmania species. Herein, we aimed to evaluate the sensitivity, specificity, accuracy, and limitations of a HSP70-HRM protocol both as a diagnostic scheme applied in clinical samples and as a species typing tool for laboratory research and reference services. Our data reveal the pronounced species-typing potential of the HSP70-HRM in DNA from cultured parasites. For clinical samples, however, we advise caution due to parasite load-dependent accuracy. In light of these findings and considering the importance of parasite load determination for clinical and research purposes, we recommend the integration of the presented typing scheme and the previously published Leishmania quantifying approach as combined tools for clinicians, surveillance, and research.
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Affiliation(s)
- Camila Patricio Braga Filgueira
- Leishmaniasis Research Laboratory, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro 21040-360, Brazil; (C.P.B.F.); (L.M.C.); (E.C.)
| | - Daniela Pitta-Pereira
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, FIOCRUZ, Pavilhão Leônidas Deane, Sala 209, Avenida Brasil 4365, Manguinhos, Rio de Janeiro 21045-900, Brazil; (D.P.-P.); (C.B.)
| | - Lilian Motta Cantanhêde
- Leishmaniasis Research Laboratory, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro 21040-360, Brazil; (C.P.B.F.); (L.M.C.); (E.C.)
- Laboratório de EpiGenética, Fiocruz Rondônia, Rua da Beira, 7671, Porto Velho 76812-245, Brazil; (G.E.M.F.); (S.D.R.)
- Instituto Nacional de Ciência e Tecnologia de Epidemiologia da Amazônia Ocidental, INCT EpiAmO, Porto Velho 76812-100, Brazil
| | | | - Sayonara Dos Reis
- Laboratório de EpiGenética, Fiocruz Rondônia, Rua da Beira, 7671, Porto Velho 76812-245, Brazil; (G.E.M.F.); (S.D.R.)
| | - Elisa Cupolillo
- Leishmaniasis Research Laboratory, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro 21040-360, Brazil; (C.P.B.F.); (L.M.C.); (E.C.)
- Instituto Nacional de Ciência e Tecnologia de Epidemiologia da Amazônia Ocidental, INCT EpiAmO, Porto Velho 76812-100, Brazil
| | - Otacilio C. Moreira
- Laboratory of Molecular Virology and Parasitology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro 21040-360, Brazil
| | - Constança Britto
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, FIOCRUZ, Pavilhão Leônidas Deane, Sala 209, Avenida Brasil 4365, Manguinhos, Rio de Janeiro 21045-900, Brazil; (D.P.-P.); (C.B.)
| | - Mariana Côrtes Boité
- Leishmaniasis Research Laboratory, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro 21040-360, Brazil; (C.P.B.F.); (L.M.C.); (E.C.)
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Chicharro C, Nieto J, Miguelañez S, Garcia E, Ortega S, Peña A, Rubio JM, Flores-Chavez M. Molecular Diagnosis of Leishmaniasis in Spain: Development and Validation of Ready-To-Use Gel-Form Nested and Real-Time PCRs To Detect Leishmania spp. Microbiol Spectr 2023; 11:e0335422. [PMID: 37014253 PMCID: PMC10269443 DOI: 10.1128/spectrum.03354-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 03/08/2023] [Indexed: 04/05/2023] Open
Abstract
Leishmaniasis is an endemic parasitic disease in at least 98 countries. In Spain, it is considered a zoonosis caused by Leishmania infantum, with an annual incidence of 0.62 cases/100,000 inhabitants. The predominant clinical manifestations are the cutaneous (CL) and visceral forms (VL), and the diagnosis is performed by parasitological, serological, and molecular tests. At the WHO Collaborating Center for Leishmaniasis (WHOCCLeish), routine diagnostic tests are based on a nested PCR (Ln-PCR), culture, and serological tests. To simplify our PCR protocol, we aimed to develop and validate a ready-to-use nested gel-form PCR (LeishGelPCR) and a duplex real-time PCR (qPCR) that allowed simultaneous detection of Leishmania and mammalian DNA as an internal control (Leish-qPCR). Clinical validation was performed in 200 samples from the WHOCCLeish collection; 92 and 85 out of 94 and 87 samples were positive by LeishGelPCR and Leish-qPCR, respectively, showing a sensitivity of 98% in both approaches. The specificity was 100% for LeishGelPCR and 98% for Leish-qPCR. The limits of detection of both protocols were similar (0.5 and 0.2 parasites/reaction). Parasite loads in VL and CL forms were similar, although high loads were observed when invasive samples were tested. In conclusion, LeishGelPCR and Leish-qPCR showed excellent performance in the diagnosis of leishmaniasis. These new forms of 18S rRNA gene PCR are equivalent to Ln-PCR and can be introduced in the algorithm for CL and VL diagnosis. IMPORTANCE Although the gold standard for diagnosis of leishmaniasis is the microscopic observation of amastigotes, molecular techniques are becoming a cost-efficient alternative. Currently, PCR is a routine resource that is used in many reference microbiology laboratories. In this article, we have described two ways to improve the reproducibility and usability of the molecular detection of Leishmania spp. These new approaches could be introduced even in middle- and low-resource laboratories; one is a ready-to-use gel-form system of a nested PCR and the other is a real-time PCR. We show why molecular diagnosis is the best methodology to confirm a clinical suspicion of leishmaniasis with higher sensitivity than traditional methods, thus facilitating early diagnosis and timely treatment of human leishmaniasis.
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Affiliation(s)
- Carmen Chicharro
- Reference and Research Laboratory for Parasitology, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC-ISCIII), Madrid, Spain
- WHO Collaborating Center for Leishmaniasis (WHOCCLeish), Madrid, Spain
| | - Javier Nieto
- Reference and Research Laboratory for Parasitology, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC-ISCIII), Madrid, Spain
- WHO Collaborating Center for Leishmaniasis (WHOCCLeish), Madrid, Spain
| | - Silvia Miguelañez
- Reference and Research Laboratory for Parasitology, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- WHO Collaborating Center for Leishmaniasis (WHOCCLeish), Madrid, Spain
| | - Emilia Garcia
- Reference and Research Laboratory for Parasitology, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- WHO Collaborating Center for Leishmaniasis (WHOCCLeish), Madrid, Spain
| | - Sheila Ortega
- Reference and Research Laboratory for Parasitology, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Ana Peña
- Reference and Research Laboratory for Parasitology, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Jose Miguel Rubio
- Reference and Research Laboratory for Parasitology, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC-ISCIII), Madrid, Spain
| | - Maria Flores-Chavez
- Reference and Research Laboratory for Parasitology, National Centre for Microbiology, Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Fundación Mundo Sano, Madrid, Spain
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Palacios G, Vega-García E, Valladares B, Pérez JA, Dorta-Guerra R, Carmelo E. Gene Expression Profiling of Classically Activated Macrophages in Leishmania infantum Infection: Response to Metabolic Pre-Stimulus with Itaconic Acid. Trop Med Infect Dis 2023; 8:tropicalmed8050264. [PMID: 37235312 DOI: 10.3390/tropicalmed8050264] [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: 03/29/2023] [Revised: 04/21/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
Leishmania infection of phagocytic cells, such as macrophages, induces the differentiation of infected cells into different phenotypes according to their surrounding microenvironments. The classical activation of macrophages involves metabolic reprogramming, in which several metabolites such as succinate, fumarate and itaconate are accumulated. The immunoregulatory functions of itaconate in the context of Leishmania infection were investigated in this paper. Ex vivo bone marrow-derived macrophages were differentiated into classically activated macrophages through IFNG activation and infection with Leishmania infantum. A high-throughput real-time qPCR experiment was designed for the analyses of 223 genes involved in immune response and metabolism. The transcriptional profile of classically activated macrophages revealed the enrichment of the IFNG response pathways and the upregulation of genes such as Cxcl9, Irf1, Acod1, Il12b, Il12rb1, Nos2 or Stat1. In vitro pre-stimulation with itaconate induced a loss of the parasite control and the upregulation of genes related to local acute inflammatory response. Our results reveal that itaconate accumulation dampened classically activated macrophage antiparasitic activity, and this is reflected by the differential expression of the Il12b, Icosl and Mki67 genes. The possibility of inducing parasite-killing responses in the host through metabolic reprograming is an interesting approach for the treatment of Leishmania infections that will undoubtedly attract increasing attention in the coming years.
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Affiliation(s)
- Génesis Palacios
- Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias (IUESTPC), Universidad de La Laguna (ULL), Avenida Astrofísico Francisco Sánchez s/n, 38200 La Laguna, Tenerife, Spain
| | - Elva Vega-García
- Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias (IUESTPC), Universidad de La Laguna (ULL), Avenida Astrofísico Francisco Sánchez s/n, 38200 La Laguna, Tenerife, Spain
| | - Basilio Valladares
- Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias (IUESTPC), Universidad de La Laguna (ULL), Avenida Astrofísico Francisco Sánchez s/n, 38200 La Laguna, Tenerife, Spain
- Departamento de Obstetricia y Ginecología, Pediatría, Medicina Preventiva y Salud PÚblica, Toxicología, Medicina Legal y Forense y Parasitología, Universidad de La Laguna, 38200 La Laguna, Tenerife, Spain
| | - José Antonio Pérez
- Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias (IUESTPC), Universidad de La Laguna (ULL), Avenida Astrofísico Francisco Sánchez s/n, 38200 La Laguna, Tenerife, Spain
- Departamento de Bioquímica, Microbiología, Biología Celular y Genética, Facultad de Ciencias, Universidad de La Laguna, 38200 La Laguna, Tenerife, Spain
| | - Roberto Dorta-Guerra
- Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias (IUESTPC), Universidad de La Laguna (ULL), Avenida Astrofísico Francisco Sánchez s/n, 38200 La Laguna, Tenerife, Spain
- Departamento de Matemáticas, Estadística e Investigación Operativa, Facultad de Ciencias, Universidad de La Laguna, 38200 La Laguna, Tenerife, Spain
| | - Emma Carmelo
- Instituto Universitario de Enfermedades Tropicales y Salud Pública de Canarias (IUESTPC), Universidad de La Laguna (ULL), Avenida Astrofísico Francisco Sánchez s/n, 38200 La Laguna, Tenerife, Spain
- Departamento de Obstetricia y Ginecología, Pediatría, Medicina Preventiva y Salud PÚblica, Toxicología, Medicina Legal y Forense y Parasitología, Universidad de La Laguna, 38200 La Laguna, Tenerife, Spain
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11
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Detecting Leishmania in dogs: A hierarchical-modeling approach to investigate the performance of parasitological and qPCR-based diagnostic procedures. PLoS Negl Trop Dis 2022; 16:e0011011. [PMID: 36525465 PMCID: PMC9803295 DOI: 10.1371/journal.pntd.0011011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 12/30/2022] [Accepted: 12/08/2022] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Domestic dogs are primary reservoir hosts of Leishmania infantum, the agent of visceral leishmaniasis. Detecting dog infections is central to epidemiological inference, disease prevention, and veterinary practice. Error-free diagnostic procedures, however, are lacking, and the performance of those available is difficult to measure in the absence of fail-safe "reference standards". Here, we illustrate how a hierarchical-modeling approach can be used to formally account for false-negative and false-positive results when investigating the process of Leishmania detection in dogs. METHODS/FINDINGS We studied 294 field-sampled dogs of unknown infection status from a Leishmania-endemic region. We ran 350 parasitological tests (bone-marrow microscopy and culture) and 1,016 qPCR assays (blood, bone-marrow, and eye-swab samples with amplifiable DNA). Using replicate test results and site-occupancy models, we estimated (a) clinical sensitivity for each diagnostic procedure and (b) clinical specificity for qPCRs; parasitological tests were assumed 100% specific. Initial modeling revealed qPCR specificity < 94%; we tracked the source of this unexpected result to some qPCR plates having subtle signs of possible contamination. Using multi-model inference, we formally accounted for suspected plate contamination and estimated qPCR sensitivity at 49-53% across sample types and dog clinical conditions; qPCR specificity was high (95-96%), but fell to 81-82% for assays run in plates with suspected contamination. The sensitivity of parasitological procedures was low (~12-13%), but increased to ~33% (with substantial uncertainty) for bone-marrow culture in seriously-diseased dogs. Leishmania-infection frequency estimates (~49-50% across clinical conditions) were lower than observed (~60%). CONCLUSIONS We provide statistical estimates of key performance parameters for five diagnostic procedures used to detect Leishmania in dogs. Low clinical sensitivies likely reflect the absence of Leishmania parasites/DNA in perhaps ~50-70% of samples drawn from infected dogs. Although qPCR performance was similar across sample types, non-invasive eye-swabs were overall less likely to contain amplifiable DNA. Finally, modeling was instrumental to discovering (and formally accounting for) possible qPCR-plate contamination; even with stringent negative/blank-control scoring, ~4-5% of positive qPCRs were most likely false-positives. This work shows, in sum, how hierarchical site-occupancy models can sharpen our understanding of the problem of diagnosing host infections with hard-to-detect pathogens including Leishmania.
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12
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Laboratory diagnostics for human Leishmania infections: a polymerase chain reaction-focussed review of detection and identification methods. Parasit Vectors 2022; 15:412. [PMID: 36335408 PMCID: PMC9636697 DOI: 10.1186/s13071-022-05524-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/02/2022] [Indexed: 11/08/2022] Open
Abstract
Leishmania infections span a range of clinical syndromes and impact humans from many geographic foci, but primarily the world's poorest regions. Transmitted by the bite of a female sand fly, Leishmania infections are increasing with human movement (due to international travel and war) as well as with shifts in vector habitat (due to climate change). Accurate diagnosis of the 20 or so species of Leishmania that infect humans can lead to the successful treatment of infections and, importantly, their prevention through modelling and intervention programs. A multitude of laboratory techniques for the detection of Leishmania have been developed over the past few decades, and although many have drawbacks, several of them show promise, particularly molecular methods like polymerase chain reaction. This review provides an overview of the methods available to diagnostic laboratories, from traditional techniques to the now-preferred molecular techniques, with an emphasis on polymerase chain reaction-based detection and typing methods.
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Dueñas E, Nakamoto JA, Cabrera-Sosa L, Huaihua P, Cruz M, Arévalo J, Milón P, Adaui V. Novel CRISPR-based detection of Leishmania species. Front Microbiol 2022; 13:958693. [PMID: 36187950 PMCID: PMC9520526 DOI: 10.3389/fmicb.2022.958693] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 07/06/2022] [Indexed: 12/26/2022] Open
Abstract
Tegumentary leishmaniasis, a disease caused by protozoan parasites of the genus Leishmania, is a major public health problem in many regions of Latin America. Its diagnosis is difficult given other conditions resembling leishmaniasis lesions and co-occurring in the same endemic areas. A combination of parasitological and molecular methods leads to accurate diagnosis, with the latter being traditionally performed in centralized reference and research laboratories as they require specialized infrastructure and operators. Clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas) systems have recently driven innovative tools for nucleic acid detection that combine high specificity, sensitivity and speed and are readily adaptable for point-of-care testing. Here, we harnessed the CRISPR-Cas12a system for molecular detection of Leishmania spp., emphasizing medically relevant parasite species circulating in Peru and other endemic areas in Latin America, with Leishmania (Viannia) braziliensis being the main etiologic agent of cutaneous and mucosal leishmaniasis. We developed two assays targeting multi-copy targets commonly used in the molecular diagnosis of leishmaniasis: the 18S ribosomal RNA gene (18S rDNA), highly conserved across Leishmania species, and a region of kinetoplast DNA (kDNA) minicircles conserved in the L. (Viannia) subgenus. Our CRISPR-based assays were capable of detecting down to 5 × 10−2 (kDNA) or 5 × 100 (18S rDNA) parasite genome equivalents/reaction with PCR preamplification. The 18S PCR/CRISPR assay achieved pan-Leishmania detection, whereas the kDNA PCR/CRISPR assay was specific for L. (Viannia) detection. No cross-reaction was observed with Trypanosoma cruzi strain Y or human DNA. We evaluated the performance of the assays using 49 clinical samples compared to a kDNA real-time PCR assay as the reference test. The kDNA PCR/CRISPR assay performed equally well as the reference test, with positive and negative percent agreement of 100%. The 18S PCR/CRISPR assay had high positive and negative percent agreement of 82.1% and 100%, respectively. The findings support the potential applicability of the newly developed CRISPR-based molecular tools for first-line diagnosis of Leishmania infections at the genus and L. (Viannia) subgenus levels.
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Affiliation(s)
- Eva Dueñas
- Laboratory of Biomolecules, Faculty of Health Sciences, Universidad Peruana de Ciencias Aplicadas (UPC), Lima, Peru
| | - Jose A. Nakamoto
- Laboratory of Biomolecules, Faculty of Health Sciences, Universidad Peruana de Ciencias Aplicadas (UPC), Lima, Peru
| | - Luis Cabrera-Sosa
- Laboratory of Biomolecules, Faculty of Health Sciences, Universidad Peruana de Ciencias Aplicadas (UPC), Lima, Peru
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Percy Huaihua
- Laboratorio de Patho-antígenos, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - María Cruz
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Hospital Nacional Adolfo Guevara Velasco, Cusco, Peru
| | - Jorge Arévalo
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Laboratorio de Patho-antígenos, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Pohl Milón
- Laboratory of Biomolecules, Faculty of Health Sciences, Universidad Peruana de Ciencias Aplicadas (UPC), Lima, Peru
| | - Vanessa Adaui
- Laboratory of Biomolecules, Faculty of Health Sciences, Universidad Peruana de Ciencias Aplicadas (UPC), Lima, Peru
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- *Correspondence: Vanessa Adaui,
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de Faria VCS, Gonçalves DU, Soares ARC, Barbosa PH, Saliba JW, de Souza CSA, Cota GF, de Avelar DM. Impact assessment of different DNA extraction methods for non-invasive molecular diagnosis of tegumentary leishmaniasis. Acta Trop 2022; 227:106275. [PMID: 34906549 DOI: 10.1016/j.actatropica.2021.106275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 12/09/2021] [Accepted: 12/10/2021] [Indexed: 11/01/2022]
Abstract
The aim of this study was to evaluate two methods of nucleic acid extraction (spin-column-based method - commercial kit and direct boil - DB) from swab sampling compared to biopsy sampling for the diagnosis of tegumentary leishmaniasis (TL), (cutaneous - CL and mucocutaneous - MCL forms). The impact of these nucleic acid extraction protocols on different types of PCR and LAMP techniques were compared regarding nucleic acid quality, molecular assays accuracy, indirect quantitation, and costs. The evaluated patients were 57 TL cases (36 CL and 21 MCL) and 34 non-cases. Swab samples extracted by the DB method showed a higher DNA degradation rate and worse DNA quality in comparison to the commercial kit. Molecular tests performed on biopsy samples showed identical or higher performance in all analysis, as compared to their own performance on swab samples for TL (CL and MCL). However, only the SSU rRNA TaqMan™ RT-PCR test showed a significant difference between the performance of biopsy and swab samples extracted by commercial kit. The kDNA-cPCR coupled with swab extracted by commercial kit showed the highest accuracy (95.6%) for TL diagnosis. The sensitivity of the LAMP-RT 18S method in swab samples extracted with a commercial kit (82.5%) was close to that found in biopsy samples (86%) for TL diagnosis. The DB extraction method presented the lowest cost. The use of swab as a minimally-invasive sampling method, associated with an efficient nucleic acid extraction protocol, may represent a low-cost alternative for the diagnosis of CL and MCL.
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Tawfeeq HM, Ali SA. Molecular-based assay for genotyping Leishmania spp. from clinically suspected cutaneous leishmaniasis lesions in the Garmian area, Kurdistan Region of Iraq. Parasite Epidemiol Control 2022; 17:e00240. [PMID: 35141432 PMCID: PMC8810569 DOI: 10.1016/j.parepi.2022.e00240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/25/2021] [Accepted: 01/18/2022] [Indexed: 11/16/2022] Open
Affiliation(s)
- Hassan Mohammad Tawfeeq
- Nursing Department, Kalar Technical College, Sulaimani Polytechnic University, Sulaimani 46001 Kalar, Kurdistan Region, Iraq
- Department of Microbiology, College of Medicine, University of Sulaimani, Kurdistan Region, Iraq
- Corresponding author at: Nursing Department, Kalar Technical College, Sulaimani Polytechnic University, 46001 Kalar, Kurdistan Region, Iraq.
| | - Shahnaz AbdulKader Ali
- Department of Microbiology, College of Medicine, University of Sulaimani, Kurdistan Region, Iraq
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Hashish A, Sinha A, Mekky A, Sato Y, Macedo NR, El-Gazzar M. Development and Validation of Two Diagnostic Real-Time PCR (TaqMan) Assays for the Detection of Bordetella avium from Clinical Samples and Comparison to the Currently Available Real-Time TaqMan PCR Assay. Microorganisms 2021; 9:microorganisms9112232. [PMID: 34835358 PMCID: PMC8619015 DOI: 10.3390/microorganisms9112232] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/13/2021] [Accepted: 10/19/2021] [Indexed: 12/03/2022] Open
Abstract
Bordetella avium (BA) is one of many pathogens that cause respiratory diseases in turkeys. However, other bacterial species can easily overgrow it during isolation attempts. This makes confirming the diagnosis of BA as the causative agent of turkey coryza more difficult. Currently, there are two PCR assays for the molecular detection of BA. One is conventional gel-based PCR and the other is TaqMan real-time PCR (qPCR) assay. However, multiple pitfalls were detected in both assays regarding their specificity, sensitivity, and efficiency, which limits their utility as diagnostic tools. In this study, we developed and validated two TaqMan qPCR assays and compared their performance to the currently available TaqMan qPCR. The two assays were able to correctly identify all BA isolates and showed negative results against a wide range of different microorganisms. The two assays were found to have high efficiency with a detection limit of approximately 1 × 103 plasmid DNA Copies/mL with high repeatability and reproducibility. In comparison to the currently available TaqMan qPCR assay, the newly developed assays showed significantly higher PCR efficiencies due to superior primers and probes design. The new assays can serve as a reliable tool for the sensitive, specific, and efficient diagnosis of BA.
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Affiliation(s)
- Amro Hashish
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (A.H.); (A.S.); (Y.S.); (N.R.M.)
- National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt;
| | - Avanti Sinha
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (A.H.); (A.S.); (Y.S.); (N.R.M.)
| | - Amr Mekky
- National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Agriculture Research Center, Giza 12618, Egypt;
| | - Yuko Sato
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (A.H.); (A.S.); (Y.S.); (N.R.M.)
| | - Nubia R. Macedo
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (A.H.); (A.S.); (Y.S.); (N.R.M.)
| | - Mohamed El-Gazzar
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA; (A.H.); (A.S.); (Y.S.); (N.R.M.)
- Correspondence: ; Tel.: +1-706-540-3037
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Cantanhêde LM, Mattos CB, Cruz AK, Ikenohuchi YJ, Fernandes FG, Medeiros EHRT, da Silva-Júnior CF, Cupolillo E, Ferreira GEM, Ferreira RDGM. Overcoming the Negligence in Laboratory Diagnosis of Mucosal Leishmaniasis. Pathogens 2021; 10:pathogens10091116. [PMID: 34578149 PMCID: PMC8465713 DOI: 10.3390/pathogens10091116] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/12/2021] [Accepted: 08/25/2021] [Indexed: 11/27/2022] Open
Abstract
The northern region of Brazil, which has the largest number of cases of tegumentary leishmaniasis (TL) in the country, is also the region that has the highest diversity of species of vectors and Leishmania parasites. In this region, cases of mucosal leishmaniasis (ML), a clinical form of TL, exceed the national average of cases, reaching up to 12% of the total annual TL notifications. ML is associated with multiple factors, such as the parasite species and the viral endosymbiont Leishmania RNA virus 1 (LRV1). Being a chronic parasitological disease, laboratory diagnosis of ML poses a challenge for health services. Here, we evaluated more than 700 clinical samples from patients with clinical suspicion of TL, including patients with cutaneous leishmaniasis (CL) and mucosal leishmaniasis, comparing the results of parasitological tests—direct parasitological examination by microscopy (DP) and conventional PCR (cPCR) targeting of both kDNA and hsp70. The DP was performed by collecting material from lesions through biopsies (mucosal lesions) or scarification (cutaneous lesions); for PCR, a cervical brush was used for sample collection. Blood samples were tested employing standardized real-time PCR (qPCR) protocol targeting the HSP70 gene. PCR tests showed higher sensitivity than DP for both CL and ML samples. Considering ML samples only (N = 89), DP showed a sensitivity of 49.4% (N = 44) against 98.8% (N = 88) for kDNA PCR. The qPCR hsp70 for blood samples from patients with ML (N = 14) resulted in superior sensitivity (50%; N = 7) compared to DP (21.4%; N = 3) for samples from the same patients. Our results reinforced the need to implement a molecular test for the diagnosis of ML, in addition to proposing methods less invasive for collecting material from TL patients. Sample collection using a cervical brush in lesions observed in CL and ML patients is easy to perform and less invasive, compared to scarification and biopsies. Blood samples could be a good source for qPCR diagnosis for ML patients. Thus, we propose here a standardized method for collection and for performing of molecular diagnosis of clinical samples from suspicious ML patients that can be applied in reference services for improving ML diagnosis.
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Affiliation(s)
- Lilian Motta Cantanhêde
- Laboratory of Genetic Epidemiology, FIOCRUZ, Porto Velho 76812245, Rondonia, Brazil
- Leishmaniasis Research Laboratory, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro 21040360, Rio de Janeiro, Brazil
| | | | - Ana Karoline Cruz
- Laboratory of Genetic Epidemiology, FIOCRUZ, Porto Velho 76812245, Rondonia, Brazil
| | | | | | | | | | - Elisa Cupolillo
- Leishmaniasis Research Laboratory, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro 21040360, Rio de Janeiro, Brazil
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Aqeele G, Shayan P, Ebrahimzade Abkooh E, Mohebali M. Evaluation of curcumin and CM11 peptide alone and in combination against amastigote form of Iranian strain of L. major (MRHO/IR75/ER) in vitro. Exp Parasitol 2021; 229:108151. [PMID: 34419412 DOI: 10.1016/j.exppara.2021.108151] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/18/2021] [Accepted: 08/18/2021] [Indexed: 01/29/2023]
Abstract
Curcumin (diferuloylmethane) is the main phytochemical of Curcuma longa Linn, an extract of the rhizome turmeric. For thousands of years, turmeric among other natural products has been used as a dietary spice and as a medicinal plant in Asian countries. The present study reports the leishmanicidal activity of curcumin in different concentrations (10 μM, 20 μM, 40 μM). It is also showing the effect of CM11 peptide (8 μM) alone and in combination with curcumin (10 and 20 μM) as a leishmanicidal drug. The experiments were performed with the amastigote form of Leishmania major (MRHO/IR/75/ER) in vitro and the leishmanicidal activity was analyzed after 12 and 24 h of incubation by Giemsa and DAPI staining. Further investigation was done by using semi-quantitative PCR with new designed common primer pair derived from an 18S rRNA gene belonging to the L. major and mouse, which amplified the above-mentioned gene segments simultaneously with different PCR product size. Our findings showed that curcumin had leishmanicidal activity in a dose and time-dependent manner and its lowest effective dose was at concentrations of 40 μM afetr12 h and 10 μM after 24 h. The IC50 value of curcumin against amastigote forms of L. major was 21.12 μM and 11.77 μM after 12 and 24 h, respectively. Treatment of amastigote form with CM11 (8 μM) alone and in combination with curcumin (10 μM and 20 μM) showed less leishmanicidal activity. Interestingly, CM11 in combination with curcumin (10 μM and 20 μM) had even less leishmanicidal effect compared to curcumin alone in the same concentrations (10 μM and 20 μM). The semi-quantitative PCR analysis confirmed the data achieved by Giemsa and DAPI staining and showed that curcumin reduced the PCR product derived from amastigote form in concentration and time-dependent manner compared to the genome of the host cells.
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Affiliation(s)
- G Aqeele
- Department of Parasitology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran; Department of Microbiology, Faculty of Medicine, University of Wasit, Iraq
| | - P Shayan
- Department of Parasitology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran; Institute Molecular Biological System Transfer (MBST), Tehran, Iran.
| | - E Ebrahimzade Abkooh
- Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
| | - M Mohebali
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
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19
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Filgueira CPB, Moreira OC, Cantanhêde LM, de Farias HMT, Porrozzi R, Britto C, Boité MC, Cupolillo E. Comparison and clinical validation of qPCR assays targeting Leishmania 18S rDNA and HSP70 genes in patients with American Tegumentary Leishmaniasis. PLoS Negl Trop Dis 2020; 14:e0008750. [PMID: 33044986 PMCID: PMC7581006 DOI: 10.1371/journal.pntd.0008750] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 10/22/2020] [Accepted: 08/26/2020] [Indexed: 12/31/2022] Open
Abstract
Leishmaniasis is a worldwide neglected disease, encompassing asymptomatic infections and different clinical forms, such as American Tegumentary Leishmaniasis (ATL) which is part of the complex of diseases caused by protozoan parasites from Leishmania genus, transmitted by sand fly vectors. As a neglected disease, much effort is still needed in treatment and diagnosis. Currently, ATL diagnosis is mainly made by parasite detection by microscopy. The sensitivity of the method varies, and factors such as collection procedures interfere. Molecular approaches, specially based on Real Time PCR (qPCR) technique, has been widely used to detect Leishmania infection and to quantify parasite load, once it is a simple, rapid and sensitive methodology, capable to detect low parasite concentrations and less prone to variability. Although many studies have been already published addressing the use of this technique, an improvement on these methodologies, including an analytical validation, standardization and data association is demanded. Moreover, a proper validation by the assay by the use of clinical samples is still required. In this sense, the purpose of the present work is to compare the performance of qPCR using two commonly used targets (18S rDNA and HSP70) with an internal control (RNAse P) in multiplex reactions. Additionally, we validated reactions by assaying 88 samples from patients presenting different clinical forms of leishmaniasis (cutaneous, mucosal, recent and old lesions), representing the diversity found in Brazil's Amazon Region. Following the methodology proposed herein, the results indicate the use of both qPCR assays, 18S rDNA and HSP70, to achieve a very good net sensitivity (98.5%) and specificity (100%), performing simultaneous or sequential testing, respectively. With this approach, our main goal is to conclude the first step of a further multicenter study to propose the standardization of detection and quantification of Leishmania.
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Affiliation(s)
- Camila Patricio Braga Filgueira
- Laboratório de Pesquisa em Leishmaniose, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Otacilio Cruz Moreira
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
| | - Lilian Motta Cantanhêde
- Laboratório de Pesquisa em Leishmaniose, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratório de Epidemiologia Genética, Fundação Oswaldo Cruz, Unidade Rondônia, Porto Velho, Rondônia, Brazil
| | - Heloísa Martins Teixeira de Farias
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Renato Porrozzi
- Laboratório de Pesquisa em Leishmaniose, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Constança Britto
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Mariana Côrtes Boité
- Laboratório de Pesquisa em Leishmaniose, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Elisa Cupolillo
- Laboratório de Pesquisa em Leishmaniose, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil
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20
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Rosales-Chilama M, Diaz-Moreno N, Prieto MD, Giraldo-Parra L, Martínez-Valencia ÁJ, Gomez MA. Comparative Assessment of DNA Targets and Amplification Methods for Leishmania (Viannia) Detection in Human Samples. Am J Trop Med Hyg 2020; 102:1323-1327. [PMID: 32228793 PMCID: PMC7253133 DOI: 10.4269/ajtmh.19-0691] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Multiple polymerase chain reaction (PCR)-based approaches have been developed for Leishmania detection in clinical and laboratory samples, and this diversity limits inter-study comparisons, meta-analyses, and generalization of findings. Towards harmonization of a molecular tool for detection of Leishmania (Viannia) for research purposes, we evaluated the concordance of 18SrDNA quantitative polymerase chain reaction (qPCR) and minicircle kinetoplastid DNA (mkDNA) PCR followed by Southern blot (PCR-SB) in in vitro infection systems and in lesion and mucosal swab samples from Colombian patients with cutaneous leishmaniasis caused by L. (Viannia). The lower limit of parasite detection of 18SrDNA qPCR and mkDNA PCR-SB was 10−1 promastigotes and one intracellular amastigote per reaction. From cutaneous lesions (n = 63), an almost perfect concordance was found between the methods (κ = 0.92, 95% CI: 0.82–1.00). Despite equal limits of detection, mkDNA PCR-SB was more efficient for parasite detection in mucosal samples than 18SrDNA qPCR or 18SrDNA digital droplet PCR. The high concordance, sensitivity, scaling potential, and feasibility of implementation of the 18SrDNA qPCR, support its selection as the L. (Viannia) in research laboratories, as a first step towards harmonization of research protocols in the region.
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Affiliation(s)
- Mariana Rosales-Chilama
- Universidad Icesi, Cali, Colombia.,Centro Internacional de Entrenamiento e Investigaciones Médicas-CIDEIM, Cali, Colombia
| | - Nicole Diaz-Moreno
- Universidad Icesi, Cali, Colombia.,Centro Internacional de Entrenamiento e Investigaciones Médicas-CIDEIM, Cali, Colombia
| | - Miguel Darío Prieto
- Centro Internacional de Entrenamiento e Investigaciones Médicas-CIDEIM, Cali, Colombia
| | - Lina Giraldo-Parra
- Centro Internacional de Entrenamiento e Investigaciones Médicas-CIDEIM, Cali, Colombia
| | | | - María Adelaida Gomez
- Universidad Icesi, Cali, Colombia.,Centro Internacional de Entrenamiento e Investigaciones Médicas-CIDEIM, Cali, Colombia
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21
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Escobar DF, Diaz-Dinamarca DA, Hernández CF, Soto DA, Manzo RA, Alarcón PI, Pinto CH, Bastias DN, Oberg-Bravo CN, Rojas R, Illanes SE, Kalergis AM, Vasquez AE. Development and analytical validation of real-time PCR for the detection of Streptococcus agalactiae in pregnant women. BMC Pregnancy Childbirth 2020; 20:352. [PMID: 32517670 PMCID: PMC7285471 DOI: 10.1186/s12884-020-03038-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 05/27/2020] [Indexed: 11/10/2022] Open
Abstract
Background Group B Streptococcus (GBS) is the leading cause of invasive neonatal infection. In this study, we aimed to evaluate the analytical validation of qualitative real-time polymerase chain reaction (qPCR) as a means to detect GBS. Methods Genomic DNA (gDNA) was purified from 12 ATCC bacterial strains, two belonging to GBS and the remainder acting as negative controls. Additionally, gDNA was isolated from 21 strains of GBS from various serotypes (Ia, Ib and II-VIII). All gDNA was used to evaluate the analytical validation of the qPCR method employing a specific Taqman probe. Inclusivity, exclusivity, anticipated reportable range, the limit of detection and robustness were evaluated. The methods used are described in international guidelines and other existing reports. The performance of this qPCR method for detecting GBS was compared to other microbiological methods used with vaginal-rectal samples from pregnant women. Results Our qPCR method for detecting GBS was analytically validated. It has a limit of detection of 0.7 GE/μL and 100% analytical specificity. It detects all strains of GBS with the same level of performance as microbiological methods. Conclusion Data suggest that this qPCR method performs adequately as a means to detect GBS in vaginal-rectal swabs from pregnant women.
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Affiliation(s)
- Daniel F Escobar
- Sección de Biotecnología, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Diego A Diaz-Dinamarca
- Sección de Biotecnología, Instituto de Salud Pública de Chile, Santiago, Chile.,Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carlos F Hernández
- Sección de Biotecnología, Instituto de Salud Pública de Chile, Santiago, Chile.,Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santos Dumont 964, Independencia, 8380494, Santiago, Chile
| | - Daniel A Soto
- Sección de Biotecnología, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Ricardo A Manzo
- Sección de Biotecnología, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Pedro I Alarcón
- Sección Bacteriología del Departamento Biomédico, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Camila H Pinto
- Sección de Biotecnología, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Diego N Bastias
- Sección de Biotecnología, Instituto de Salud Pública de Chile, Santiago, Chile.,Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Escuela de Biotecnología y Escuela de Tecnología Médica, Facultad de Ciencias, Universidad Santo Tomas, Santiago, Chile
| | - Carolayn N Oberg-Bravo
- Sección de Biotecnología, Instituto de Salud Pública de Chile, Santiago, Chile.,Escuela de Biotecnología y Escuela de Tecnología Médica, Facultad de Ciencias, Universidad Santo Tomas, Santiago, Chile
| | - Robert Rojas
- Centro de Genómica y Bioinformática, Universidad Mayor, Santiago, Chile
| | - Sebastián E Illanes
- Department of Obstetrics and Gynecology, Faculty of Medicine, Universidad de los Andes, Santiago, Chile.,Department of Obstetrics and Gynecology, Clínica Dávila, Santiago, Chile
| | - Alexis M Kalergis
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Abel E Vasquez
- Sección de Biotecnología, Instituto de Salud Pública de Chile, Santiago, Chile. .,Escuela de Biotecnología y Escuela de Tecnología Médica, Facultad de Ciencias, Universidad Santo Tomas, Santiago, Chile. .,Facultad de Medicina y Ciencia, Universidad San Sebastián, Providencia, Santiago, Chile. .,Present address. Instituto de Salud Pública de Chile, Av. Marathon, Ñuñoa, 1000, Santiago, Chile.
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22
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Machado A, Lyon S, Rocha‐Silva F, Assunção C, Hernandez M, Jorge D, Cunha A, Barbosa V, Fernades B, Abreu A, Goulart L, Goulart I, Coelho E, Caligiorne R. Novel PCR primers for improved detection of
Mycobacterium leprae
and diagnosis of leprosy. J Appl Microbiol 2020; 128:1814-1819. [DOI: 10.1111/jam.14592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 01/15/2020] [Accepted: 01/21/2020] [Indexed: 11/29/2022]
Affiliation(s)
- A.S. Machado
- Hospital Santa Casa de Belo Horizonte Ensino e Pesquisa Programa de Pós‐Graduação Belo Horizonte Minas Gerais Brazil
| | - S. Lyon
- Hospital Eduardo de Menezes Belo Horizonte Minas Gerais Brazil
| | - F. Rocha‐Silva
- Hospital Santa Casa de Belo Horizonte Ensino e Pesquisa Programa de Pós‐Graduação Belo Horizonte Minas Gerais Brazil
| | - C.B. Assunção
- Hospital Santa Casa de Belo Horizonte Ensino e Pesquisa Programa de Pós‐Graduação Belo Horizonte Minas Gerais Brazil
| | - M.N. Hernandez
- Hospital Santa Casa de Belo Horizonte Ensino e Pesquisa Programa de Pós‐Graduação Belo Horizonte Minas Gerais Brazil
- Hospital Eduardo de Menezes Belo Horizonte Minas Gerais Brazil
| | - D.S. Jorge
- Hospital Santa Casa de Belo Horizonte Ensino e Pesquisa Programa de Pós‐Graduação Belo Horizonte Minas Gerais Brazil
- Hospital Eduardo de Menezes Belo Horizonte Minas Gerais Brazil
| | - A.C.G. Cunha
- Hospital Santa Casa de Belo Horizonte Ensino e Pesquisa Programa de Pós‐Graduação Belo Horizonte Minas Gerais Brazil
- Hospital Eduardo de Menezes Belo Horizonte Minas Gerais Brazil
| | - V.G. Barbosa
- Hospital Santa Casa de Belo Horizonte Ensino e Pesquisa Programa de Pós‐Graduação Belo Horizonte Minas Gerais Brazil
| | - B. Fernades
- Hospital Santa Casa de Belo Horizonte Ensino e Pesquisa Programa de Pós‐Graduação Belo Horizonte Minas Gerais Brazil
| | - A.G.S. Abreu
- Hospital Santa Casa de Belo Horizonte Ensino e Pesquisa Programa de Pós‐Graduação Belo Horizonte Minas Gerais Brazil
| | - L.R. Goulart
- Laboratório de Nanobiotecnologia Instituto de Genética e Bioquímica Universidade Federal de Uberlândia Uberlândia Minas Gerais Brazil
| | - I. Goulart
- Laboratório de Nanobiotecnologia Instituto de Genética e Bioquímica Universidade Federal de Uberlândia Uberlândia Minas Gerais Brazil
| | - E.A.F. Coelho
- Programa de Pós‐Graduação em Ciências da Saúde: Infectologia e Medicina Tropical Faculdade de Medicina Universidade Federal de Minas Gerais Belo Horizonte Minas Gerais Brazil
| | - R.B. Caligiorne
- Hospital Santa Casa de Belo Horizonte Ensino e Pesquisa Programa de Pós‐Graduação Belo Horizonte Minas Gerais Brazil
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23
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Amorim CF, Novais FO, Nguyen BT, Misic AM, Carvalho LP, Carvalho EM, Beiting DP, Scott P. Variable gene expression and parasite load predict treatment outcome in cutaneous leishmaniasis. Sci Transl Med 2019; 11:eaax4204. [PMID: 31748229 PMCID: PMC7068779 DOI: 10.1126/scitranslmed.aax4204] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 09/17/2019] [Indexed: 12/21/2022]
Abstract
Patients infected with Leishmania braziliensis develop chronic lesions that often fail to respond to treatment with antiparasite drugs. To determine whether genes whose expression is highly variable in lesions between patients might influence disease outcome, we obtained biopsies of lesions from patients before treatment with pentavalent antimony and performed transcriptomic profiling on these clinical samples. We identified genes that were highly variably expressed between patients, and the variable expression of these genes correlated with treatment outcome. Among the most variable genes in all the patients were components of the cytolytic pathway, and the expression of these genes correlated with parasite load in the skin. We demonstrated that treatment failure was linked to the cytolytic pathway activated during infection. Using a host-pathogen marker profile of as few as three genes, we showed that eventual treatment outcome could be predicted before the start of treatment in two separate cohorts of patients with cutaneous leishmaniasis (n = 21 and n = 25). These findings raise the possibility of point-of-care diagnostic screening to identify patients at high risk of treatment failure and provide a rationale for a precision medicine approach to drug selection in cutaneous leishmaniasis. This work more broadly demonstrates the value of identifying genes of high variability in other diseases to better understand and predict diverse clinical outcomes.
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Affiliation(s)
- Camila Farias Amorim
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, PA 19104-4539, USA
| | - Fernanda O Novais
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, PA 19104-4539, USA
| | - Ba T Nguyen
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, PA 19104-4539, USA
| | - Ana M Misic
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, PA 19104-4539, USA
| | - Lucas P Carvalho
- Serviço de Imunologia, Complexo Hospitalar Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia 40110-060, Brazil
- Laboratório de Pesquisas Clínicas do Instituto de Pesquisas Gonçalo Moniz, Fiocruz Bahia, 40296-710, Brazil
| | - Edgar M Carvalho
- Serviço de Imunologia, Complexo Hospitalar Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador, Bahia 40110-060, Brazil
- Laboratório de Pesquisas Clínicas do Instituto de Pesquisas Gonçalo Moniz, Fiocruz Bahia, 40296-710, Brazil
| | - Daniel P Beiting
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, PA 19104-4539, USA.
| | - Phillip Scott
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, PA 19104-4539, USA.
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24
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Gow I, Millar D, Ellis J, Melki J, Stark D. Semi-Quantitative, Duplexed qPCR Assay for the Detection of Leishmania spp. Using Bisulphite Conversion Technology. Trop Med Infect Dis 2019; 4:E135. [PMID: 31683788 PMCID: PMC6958480 DOI: 10.3390/tropicalmed4040135] [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: 10/06/2019] [Revised: 10/28/2019] [Accepted: 10/28/2019] [Indexed: 02/04/2023] Open
Abstract
Leishmaniasis is caused by the flagellated protozoan Leishmania, and is a neglected tropical disease (NTD), as defined by the World Health Organisation (WHO). Bisulphite conversion technology converts all genomic material to a simplified form during the lysis step of the nucleic acid extraction process, and increases the efficiency of multiplex quantitative polymerase chain reaction (qPCR) reactions. Through utilization of qPCR real-time probes, in conjunction with bisulphite conversion, a new duplex assay targeting the 18S rDNA gene region was designed to detect all Leishmania species. The assay was validated against previously extracted DNA, from seven quantitated DNA and cell standards for pan-Leishmania analytical sensitivity data, and 67 cutaneous clinical samples for cutaneous clinical sensitivity data. Specificity was evaluated by testing 76 negative clinical samples and 43 bacterial, viral, protozoan and fungal species. The assay was also trialed in a side-by-side experiment against a conventional PCR (cPCR), based on the Internal transcribed spacer region 1 (ITS1 region). Ninety-seven percent of specimens from patients that previously tested positive for Leishmania were positive for Leishmania spp. with the bisulphite conversion assay, and a limit of detection (LOD) of 10 copies per PCR was achieved, while the LOD of the ITS1 methodology was 10 cells/1000 genomic copies per PCR. This method of rapid, accurate and simple detection of Leishmania can lead to improved diagnosis, treatment and public health outcomes.
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Affiliation(s)
- Ineka Gow
- School of Life Sciences, University of Technology, Sydney, NSW 2007, Australia.
- Genetic Signatures Ltd., Sydney, NSW 2042, Australia.
| | | | - John Ellis
- School of Life Sciences, University of Technology, Sydney, NSW 2007, Australia.
| | - John Melki
- Genetic Signatures Ltd., Sydney, NSW 2042, Australia.
| | - Damien Stark
- Microbiology Department, St. Vincent's Hospital, Sydney, NSW 2010, Australia.
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25
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Banerjee I, Aralaguppe SG, Lapins N, Zhang W, Kazemzadeh A, Sönnerborg A, Neogi U, Russom A. Microfluidic centrifugation assisted precipitation based DNA quantification. LAB ON A CHIP 2019; 19:1657-1664. [PMID: 30931470 DOI: 10.1039/c9lc00196d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Nucleic acid amplification methods are increasingly being used to detect trace quantities of DNA in samples for various diagnostic applications. However, quantifying the amount of DNA from such methods often requires time consuming purification, washing or labeling steps. Here, we report a novel microfluidic centrifugation assisted precipitation (μCAP) method for single-step DNA quantification. The method is based on formation of a visible precipitate, which can be quantified, when an intercalating dye (GelRed) is added to the DNA sample and centrifuged for a few seconds. We describe the mechanism leading to the precipitation phenomenon. We utilize centrifugal microfluidics to precisely control the formation of the visible and quantifiable mass. Using a standard CMOS sensor for imaging, we report a detection limit of 45 ng μl-1. Furthermore, using an integrated lab-on-DVD platform we recently developed, the detection limit is lowered to 10 ng μl-1, which is comparable to those of current commercially available instruments for DNA quantification. As a proof of principle, we demonstrate the quantification of LAMP products for a HIV-1B type genome containing plasmid on the lab-on-DVD platform. The simple DNA quantification system could facilitate advanced point of care molecular diagnostics.
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Affiliation(s)
- I Banerjee
- Division of Nanobiotechnology, Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Sweden.
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26
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Ramírez JD, Herrera G, Muskus C, Mendez C, Duque MC, Butcher R. Development of a Digital Droplet Polymerase Chain Reaction (ddPCR) assay to detect Leishmania DNA in samples from Cutaneous Leishmaniasis patients. Int J Infect Dis 2019; 79:1-3. [DOI: 10.1016/j.ijid.2018.10.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 10/29/2018] [Accepted: 10/30/2018] [Indexed: 12/19/2022] Open
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27
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Antonia AL, Wang L, Ko DC. A real-time PCR assay for quantification of parasite burden in murine models of leishmaniasis. PeerJ 2018; 6:e5905. [PMID: 30430041 PMCID: PMC6231426 DOI: 10.7717/peerj.5905] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 10/09/2018] [Indexed: 12/22/2022] Open
Abstract
Eukaryotic parasites in the genus Leishmania place approximately 350 million people per year at risk of disease. In addition to their global health significance, Leishmania spp. have served as an important model for delineating basic concepts in immunology such as T-helper cell polarization. There have been many qPCR-based assays reported for measuring parasite burden in humans and animals. However, these are largely optimized for use in clinical diagnosis and not specifically for animal models. This has led several of these assays to have suboptimal characteristics for use in animal models. For example, multi-copy number genes have been frequently used to increase sensitivity but are subject to greater plasticity within the genome and thus may confound effects of experimental manipulations in animal models. In this study, we developed a sybr-green based quantitative touchdown PCR assay for a highly conserved and single-copy putative RNA-binding protein, DRBD3. With primers that share greater than 90% sequence identity across all sequenced Leishmania spp., we demonstrate that this assay has a lower limit of detection of 100 fg of parasite DNA for Leishmania major, L. donovani, L. venezuelensis, and L. panamensis. Using C57BL6/J mice, we used this assay to monitor parasite burden over 1 month of infection with two strains of L. major (Seidman and Friedlin), and L. venezeuelensis. These characteristics rival the sensitivity of previously reported qPCR based methods of parasite quantitation while amplifying a stable, single copy gene. Use of this protocol in the future will lead to improved accuracy in animal based models and help to tease apart differences in biology of host-parasite interactions.
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Affiliation(s)
- Alejandro L. Antonia
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
| | - Liuyang Wang
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
| | - Dennis C. Ko
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
- Division of Infectious Diseases, Department of Medicine, Duke University, Durham, NC, USA
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28
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Abstract
Visceral leishmaniasis (VL), a deadly parasitic disease, is a major public health concern globally. Countries affected by VL have signed the London Declaration on Neglected Tropical Diseases and committed to eliminate VL as a public health problem by 2020. To achieve and sustain VL elimination, it will become progressively important not to miss any remaining cases in the community who can maintain transmission. This requires accurate identification of symptomatic and asymptomatic carriers using highly sensitive diagnostic tools at the primary health service setting. The rK39 rapid diagnostic test (RDT) is the most widely used tool and with its good sensitivity and specificity is the first choice for decentralized diagnosis of VL in endemic areas. However, this test cannot discriminate between current, subclinical, or past infections and is useless for diagnosis of relapses and as a prognostic (cure) test. Importantly, as the goal of elimination of VL as a public health problem is approaching, the number of people susceptible to infection will increase. Therefore, correct diagnosis using a highly sensitive diagnostic test is crucial for applying appropriate treatment and management of cases. Recent advances in molecular techniques have improved Leishmania detection and quantification, and therefore this technology has become increasingly relevant due to its possible application in a variety of clinical sample types. Most importantly, given current problems in identifying asymptomatic individuals because of poor correlation between the main methods of detection, molecular tests are valuable for VL elimination programs, especially to monitor changes in burden of infection in specific communities. This review provides a comprehensive overview of the available VL diagnostics and discusses the usefulness of molecular methods in the diagnosis, quantification, and species differentiation as well as their clinical applications.
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Affiliation(s)
- Shyam Sundar
- Infectious Disease Research Laboratory, Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, 221 005, India
| | - Om Prakash Singh
- Infectious Disease Research Laboratory, Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, 221 005, India.
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Cui X, Shi Y, Zhao L, Gu S, Wei C, Yang Y, Wen S, Chen H, Ge J. Application of Real-Time Quantitative PCR to Detect Mink Circovirus in Naturally and Experimentally Infected Minks. Front Microbiol 2018; 9:937. [PMID: 29867846 PMCID: PMC5960700 DOI: 10.3389/fmicb.2018.00937] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 04/23/2018] [Indexed: 12/19/2022] Open
Abstract
The mink circovirus (MiCV), a newly discovered pathogen, is associated with diarrhea in farmed minks. The prevalence and economic importance of this virus remain poorly understood, and a quantitative method for diagnosis of MiCV infection has not been established. This research aims to develop a highly specific, sensitive, and quantitative assay for MiCV. A Real-Time quantitative polymerase chain reaction (qPCR) assay was developed to detect different isolates of the MiCV in mink samples. The qPCR system is highly sensitive with a detection limit of as low as 10 viral DNA copies. The specificity of this qPCR assay was supported by the absence of cross-reaction with other pathogens. The coefficients of variation were low for both inter-assay and intra-assay variabilities. In addition, the results also expressed the distribution of MiCV in infectious mink tissues with high levels of virus in the skeletal muscle and heart. The heart occupied a higher proportion than other tissues, which can be considered the primary source of test material. This qPCR method could be a useful tool for epidemiological studies and disease management. This method for MiCV is highly specific, sensitive, repeatable, quantitative, and can rapidly determine viral load levels in different tissues samples.
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Affiliation(s)
- Xingyang Cui
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Yunjia Shi
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Lili Zhao
- Laboratory Animal and Comparative Medicine Unit, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Shanshan Gu
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Chengwei Wei
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Yan Yang
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Shanshan Wen
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China
| | - Hongyan Chen
- Laboratory Animal and Comparative Medicine Unit, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Junwei Ge
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.,Northeastern Science Inspection Station, China Ministry of Agriculture Key Laboratory of Animal Pathogen Biology, Harbin, China
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Galluzzi L, Ceccarelli M, Diotallevi A, Menotta M, Magnani M. Real-time PCR applications for diagnosis of leishmaniasis. Parasit Vectors 2018; 11:273. [PMID: 29716641 PMCID: PMC5930967 DOI: 10.1186/s13071-018-2859-8] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 04/18/2018] [Indexed: 11/10/2022] Open
Abstract
Leishmaniasis is a vector-borne disease caused by many Leishmania species, which can infect both humans and other mammals. Leishmaniasis is a complex disease, with heterogeneous clinical manifestations ranging from asymptomatic infections to lesions at cutaneous sites (cutaneous leishmaniasis), mucosal sites (mucocutaneous leishmaniasis) or in visceral organs (visceral leishmaniasis), depending on the species and host characteristics. Often, symptoms are inconclusive and leishmaniasis can be confused with other co-endemic diseases. Moreover, co-infections (mainly with HIV in humans) can produce atypical clinical presentations. A correct diagnosis is crucial to apply the appropriate treatment and the use of molecular techniques in diagnosis of leishmaniasis has become increasingly relevant due to their remarkable sensitivity, specificity and possible application to a variety of clinical samples. Among them, real-time PCR (qPCR)-based approaches have become increasingly popular in the last years not only for detection and quantification of Leishmania species but also for species identification. However, despite qPCR-based methods having proven to be very effective in the diagnosis of leishmaniasis, a standardized method does not exist. This review summarizes the qPCR-based methods in the diagnosis of leishmaniasis focusing on the recent developments and applications in this field.
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Affiliation(s)
- Luca Galluzzi
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, via Saffi 2, 61029 Urbino, PU Italy
| | - Marcello Ceccarelli
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, via Saffi 2, 61029 Urbino, PU Italy
| | - Aurora Diotallevi
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, via Saffi 2, 61029 Urbino, PU Italy
| | - Michele Menotta
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, via Saffi 2, 61029 Urbino, PU Italy
| | - Mauro Magnani
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, via Saffi 2, 61029 Urbino, PU Italy
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León CM, Muñoz M, Tabares JH, Hernandez C, Florez C, Ayala MS, Ramírez JD. Analytical Performance of a Loop-Mediated Isothermal Amplification Assay for Leishmania DNA Detection in Sandflies and Direct Smears of Patients with Cutaneous Leishmaniasis. Am J Trop Med Hyg 2018; 98:1325-1331. [PMID: 29532767 PMCID: PMC5953379 DOI: 10.4269/ajtmh.17-0808] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 12/26/2017] [Indexed: 12/12/2022] Open
Abstract
Loop-mediated isothermal amplification (LAMP) is ideal for the detection of Leishmania DNA as it is a quick and easy-to-perform test that does not require complex or sophisticated equipment or infrastructure. However, the application of this technique in the detection of Leishmania DNA has not been comprehensively analyzed to date (analytical validation). Our objective was to evaluate the sensitivity and analytical specificity (anticipated reportable range [ARR], the limit of detection [LoD], and accuracy) of LAMP targeting the 18S rRNA gene in the diagnosis of six New World Leishmania species. We then applied the validated LAMP assay across 50 samples of sandflies and 50 direct smears from a recent outbreak of cutaneous leishmaniasis in Colombia to determine its diagnostic performance. The LAMP assay exclusively amplified the DNA of Leishmania spp., and an ARR of between 1 × 104 and 1 × 10-2 equivalent parasites/mL was determined. An LoD of 1 × 10-2 equivalent parasites/mL was established and there was no statistically significant variation in terms of accuracy. Finally, a sensitivity of 100% in direct smears and sandflies samples was calculated and a specificity of 90.9% for direct smears using microscopy as reference and 96.8% for sandflies using real-time polymerase chain reaction as reference were determined. To our knowledge, this is the first attempt to analytically validate a LAMP test to detect Leishmania DNA, which showed good diagnostic potential from sandflies and direct smear samples.
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Affiliation(s)
- Cielo M. León
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Programa de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, Colombia
- Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Marina Muñoz
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Programa de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, Colombia
| | - Juan H. Tabares
- Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Carolina Hernandez
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Programa de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, Colombia
| | - Carolina Florez
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Martha S. Ayala
- Grupo de Parasitología, Instituto Nacional de Salud, Bogotá, Colombia
| | - Juan David Ramírez
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Programa de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, Colombia
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