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Shuai Y, Xue Q, Tu H, Guo J, Teng Q, Xu Y, Xu J, Li Y, Zhou H, Zhao J. Multiplex LAMP assay for detecting the prevalent species of dust mites Dermatophagoides farinae and Dermatophagoides pteronyssinus in the domestic environment. Sci Rep 2024; 14:16156. [PMID: 38997337 PMCID: PMC11245516 DOI: 10.1038/s41598-024-66043-8] [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: 05/14/2024] [Accepted: 06/26/2024] [Indexed: 07/14/2024] Open
Abstract
Dermatophagoides farina (D. farinae) and Dermatophagoides pteronyssinus (D. pteronyssinus) are the prevalent kinds of house dust mites (HDMs). HDMs are common inhalant allergens that cause a range of allergic diseases, such as rhinitis, atopic dermatitis, and asthma. The epidemiology of these diseases is associated with exposure to mites. Therefore, in the present study, a method named multiplex loop-mediated isothermal amplification (LAMP) was developed to detect environmental dust mites. The multiplex LAMP assay allows amplification within a single tube and has an ITS plasmid detection limit as low as 40 fg/µL for both single dust mites and mixed dust mites (D. pteronyssinus and D. farinae), which is up to ten times more sensitive than classical PCR techniques. Furthermore, the multiplex LAMP method was applied to samples of single dust mites and clinical dust to confirm its validity. The multiplex LAMP assay exhibited higher sensitivity, simpler instrumentation, and visualization of test results, indicating that this method could be used as an alternative to traditional techniques for the detection of HDMs.
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Affiliation(s)
- Yujun Shuai
- Department of Medical Parasitology, Wannan Medical College, Wuhu, 241002, Anhui, China
| | - Qiqi Xue
- Department of Laboratory Medicine, Third Affiliated Hospital of Naval Medical University, Shanghai, 200438, China
| | - Huanxin Tu
- Department of Medical Parasitology, Wannan Medical College, Wuhu, 241002, Anhui, China
| | - Junjie Guo
- Department of Medical Parasitology, Qiqihaer Medical College, Qiqihaer, 161000, Heilongjiang, China
| | - Qiao Teng
- Department of Medical Parasitology, Wannan Medical College, Wuhu, 241002, Anhui, China
| | - Yueye Xu
- Department of Medical Parasitology, Wannan Medical College, Wuhu, 241002, Anhui, China
| | - Jingang Xu
- Department of Medical Parasitology, Wannan Medical College, Wuhu, 241002, Anhui, China
| | - Yuanyuan Li
- Department of Medical Parasitology, Wannan Medical College, Wuhu, 241002, Anhui, China
| | - Hongming Zhou
- Department of Medical Parasitology, Wannan Medical College, Wuhu, 241002, Anhui, China.
- Anhui Province Key Laboratory of Biological Macro-molecules Research, Wannan Medical College, Wuhu, 241002, Anhui, China.
| | - Jinhong Zhao
- Department of Medical Parasitology, Wannan Medical College, Wuhu, 241002, Anhui, China.
- Anhui Province Key Laboratory of Biological Macro-molecules Research, Wannan Medical College, Wuhu, 241002, Anhui, China.
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Crego-Vicente B, del Olmo MD, Muro A, Fernández-Soto P. Multiplexing LAMP Assays: A Methodological Review and Diagnostic Application. Int J Mol Sci 2024; 25:6374. [PMID: 38928080 PMCID: PMC11203869 DOI: 10.3390/ijms25126374] [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: 04/30/2024] [Revised: 05/27/2024] [Accepted: 06/06/2024] [Indexed: 06/28/2024] Open
Abstract
The loop-mediated isothermal amplification (LAMP) technique is a great alternative to PCR-based methods, as it is fast, easy to use and works with high sensitivity and specificity without the need for expensive instruments. However, one of the limitations of LAMP is difficulty in achieving the simultaneous detection of several targets in a single tube, as the methodologies that allow this rely on fluorogenic probes containing specific target sequences, complicating their adaptation and the optimization of assays. Here, we summarize different methods for the development of multiplex LAMP assays based on sequence-specific detection, illustrated with a schematic representation of the technique, and evaluate their practical application based on the real-time detection and quantification of results, the possibility to visualize the results at a glance, the prior stabilization of reaction components, promoting the point-of-care use, the maximum number of specific targets amplified, and the validation of the technique in clinical samples. The various LAMP multiplexing methodologies differ in their operating conditions and mechanism. Each methodology has its advantages and disadvantages, and the choice among them will depend on specific application interests.
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Affiliation(s)
| | | | - Antonio Muro
- Infectious and Tropical Diseases Research Group (e-INTRO), Biomedical Research Institute of Salamanca Research Centre for Tropical Diseases at the University of Salamanca (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37007 Salamanca, Spain; (B.C.-V.); (M.D.d.O.)
| | - Pedro Fernández-Soto
- Infectious and Tropical Diseases Research Group (e-INTRO), Biomedical Research Institute of Salamanca Research Centre for Tropical Diseases at the University of Salamanca (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37007 Salamanca, Spain; (B.C.-V.); (M.D.d.O.)
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Samsami S, Namavari S, Ataei S, Ghasemian A, Yazdanpanah A, Sepahi N, Hatam G, Faramarzi H, Mirzaei H, Ranjbar R, Ghanbariasad A. A Novel Multiplex LAMP Assay for the Rapid and Accurate Diagnosis of Visceral Leishmaniasis Caused by Leishmania infantum from Iran. J Trop Med 2023; 2023:9326183. [PMID: 38028028 PMCID: PMC10676275 DOI: 10.1155/2023/9326183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 10/30/2023] [Accepted: 11/07/2023] [Indexed: 12/01/2023] Open
Abstract
Visceral leishmaniosis (VL) is one of the neglected tropical diseases despite being responsible for serious clinical symptoms, some of which lead to fatal outcomes. Thus, there is a need to apply accurate, rapid, and specific diagnostic measurements in order to control the disease and reduce the mortality rate. We aimed to develop and validate a multiplex LAMP assay for the diagnosis of VL caused by Leishmania infantum (L. infantum). Moreover, a thorough assessment was conducted to determine the effectiveness of multiplex LAMP in identifying various Leishmania species, such as Leishmania tropica (L. tropica) and Leishmania major (L. major) in comparison to Leishmania infantum (L. infantum). The diagnostic performance of the multiplex LAMP method for VL was compared to each LAMP assay, real-time polymerase chain reaction (RT-qPCR), and nested PCR technique. Two separated primers were set and used in a multiplex LAMP assay which was designed based on the ITS2 (internal transcribed spacer II) and were selected on the basis of conserved and high copy number region. Multiplex LAMP primers were designed using an online tool available at https://www.primerexplorer.jp/e. The alignment was performed using MEGA5, and the primers were further adjusted utilizing GENE Runner software. All molecular methods were tested on the serial dilution of cloned plasmid containing ITS region from standard strains of L. infantum, L. tropica, and L. major. Moreover, multiplex LAMP assay was evaluated and compared based on both standard strains and 55 clinical samples from humans as well as dogs. Various approaches were applied to interpret the multiplex LAMP reaction which deciphered a higher sensitivity when compared to the RT-qPCR for L. infantum (one copy number of plasmid, equal to 0.85 femtograms (fg) of plasmid concentration, and 0.004 parasite DNA per μL) detection while these three standard strains of Leishmania were confirmed to contain 40 DNA copies using RT-qPCR. Additionally, the multiplex LAMP detection limit was approximately equivalent to RT-qPCR for L. major and L. tropica, which included 0.342 picograms (pg) and 342 femtograms (fg) of plasmid concentration, 4 × 103 and 4 × 102 copy number of plasmid, and 17.1 and 1.71 parasite DNA per μL for L. major and L. tropica, respectively. Nested PCR exhibited a lower detection limit for L. infantum of 4 × 106 plasmid copy number compared to multiplex LAMP and RT-qPCR. Multiplex LAMP has the potential for accurate and rapid detection of infectious disease, successful treatment, and finding and monitoring asymptomatic cases, especially in low-income countries.
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Affiliation(s)
- Sahar Samsami
- Student Research Committee, Fasa University of Medical Sciences, Fasa, Iran
- Department of Medical Biotechnologies, Fasa University of Medical Sciences, Fasa, Iran
| | - Sahar Namavari
- Department of Medical Biotechnologies, Fasa University of Medical Sciences, Fasa, Iran
| | - Saeed Ataei
- Department of Medical Biotechnologies, Fasa University of Medical Sciences, Fasa, Iran
| | - Abdolmajid Ghasemian
- Noncommunicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran
| | - Ava Yazdanpanah
- Student Research Committee, Fasa University of Medical Sciences, Fasa, Iran
- Department of Medical Biotechnologies, Fasa University of Medical Sciences, Fasa, Iran
| | - Neda Sepahi
- Noncommunicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran
| | - Gholamreza Hatam
- Department of Medical Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Hossein Faramarzi
- Department of Community Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Hadi Mirzaei
- Department of Medical Genetics, School of Medicine, Zabol University of Medical Sciences, Zabol, Iran
| | - Razie Ranjbar
- Department of Medical Biotechnologies, Fasa University of Medical Sciences, Fasa, Iran
| | - Ali Ghanbariasad
- Department of Medical Biotechnologies, Fasa University of Medical Sciences, Fasa, Iran
- Noncommunicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran
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Lopes-Luz L, Saavedra DP, Fogaça MBT, Bührer-Sékula S, Stefani MMDA. Challenges and advances in serological and molecular tests to aid leprosy diagnosis. Exp Biol Med (Maywood) 2023; 248:2083-2094. [PMID: 38059475 PMCID: PMC10800132 DOI: 10.1177/15353702231209422] [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] [Indexed: 12/08/2023] Open
Abstract
Leprosy is a neglected chronic infectious disease caused by obligate intracellular bacilli, Mycobacterium leprae and Mycobacterium lepromatosis. Despite multidrug therapy (MDT) success, leprosy accounts for more than 200,000 new cases yearly. Leprosy diagnosis remains based on the dermato-neurologic examination, but histopathology of skin biopsy and bacilloscopy of intradermal scraping are subsidiary diagnostic tests that require expertise and laboratory infrastructure. This minireview summarizes the state of the art of serologic tests to aid leprosy diagnosis, highlighting enzyme-linked immunosorbent assay (ELISA) and point-of-care tests (POCT) biotechnologies. Also, the impact of the postgenomic era on the description of new recombinantly expressed M. leprae-specific protein antigens, such as leprosy Infectious Disease Research Institute (IDRI) diagnostic (LID)-1 is summarized. Highly specific and sensitive molecular techniques to detect M. leprae DNA as the quantitative polymerase chain reaction (qPCR) and the loop-mediated isothermal amplification (LAMP) are briefly reviewed. Serology studies using phenolic glycolipid-I (PGL-I) semi-synthetic antigens, LID-1 fusion antigen, and the single fusion complex natural disaccharide-octyl (NDO)-LID show high sensitivity in multibacillary (MB) patients. However, serology is not applicable to paucibacillary patients, as they have weak humoral response and robust cell-mediated response, requiring tests for cellular biomarkers. Unlike ELISA-based tests, leprosy-specific POCT based on semi-synthetic PGL-I antigens and NDO-LID 1 antigen is easy to perform, cheaper, equipment-free, and can contribute to early diagnosis avoiding permanent incapacities and helping to interrupt M. leprae transmission. Besides its use to help diagnosis of household contacts or at-risk populations in endemic areas, potential applications of leprosy serology include monitoring MDT efficacy, identification of recent infection, especially in young children, as surrogate markers of disease progression to orient adult chemoprophylaxis and as a predictor of type 2 leprosy reactions. Advances in molecular biology techniques have reduced the complexity and execution time of qPCR confirming its utility to help diagnosis while leprosy-specific LAMP holds promise as an adjunct test to detect M. leprae DNA.
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Affiliation(s)
- Leonardo Lopes-Luz
- Laboratório de Desenvolvimento e Produção de Testes Rápidos, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia 74605-050, Brasil
- Innovation Hub in Point of Care Technologies, UFG-Merck S/A. Alliance, Goiânia 74690-900, Brasil
| | - Djairo Pastor Saavedra
- Laboratório de Desenvolvimento e Produção de Testes Rápidos, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia 74605-050, Brasil
- Innovation Hub in Point of Care Technologies, UFG-Merck S/A. Alliance, Goiânia 74690-900, Brasil
| | - Matheus Bernardes Torres Fogaça
- Laboratório de Desenvolvimento e Produção de Testes Rápidos, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia 74605-050, Brasil
- Innovation Hub in Point of Care Technologies, UFG-Merck S/A. Alliance, Goiânia 74690-900, Brasil
| | - Samira Bührer-Sékula
- Laboratório de Desenvolvimento e Produção de Testes Rápidos, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia 74605-050, Brasil
- Innovation Hub in Point of Care Technologies, UFG-Merck S/A. Alliance, Goiânia 74690-900, Brasil
| | - Mariane Martins de Araújo Stefani
- Laboratório de Desenvolvimento e Produção de Testes Rápidos, Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia 74605-050, Brasil
- Innovation Hub in Point of Care Technologies, UFG-Merck S/A. Alliance, Goiânia 74690-900, Brasil
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Yin C, Pang B, Huang Y, Li J, Meng T, Zhang M, Zhang L, Gao Y, Song X. Multiplex polymerase spiral reaction for simultaneous detection of Salmonella typhimurium and Staphylococcus aureus. Anal Biochem 2023; 667:115086. [PMID: 36813221 DOI: 10.1016/j.ab.2023.115086] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/10/2023] [Accepted: 02/15/2023] [Indexed: 02/24/2023]
Abstract
Salmonella typhimurium (S. typhimurium) and Staphylococcus aureus (S. aureus) are common food-borne pahogens that cause food poisoning in humans. In this study, we developed a method for the simultaneous determination of S. typhimurium and S. aureus based on multiplex polymerase spiral reaction (m-PSR) and melting curve analysis. Two pairs of primers were designed specifically to target the conserved invA gene of S. typhimurium and nuc gene of S. aureus, and the nucleic acid amplification reaction was achieved under isothermal conditions in the same reaction tube for 40 min at 61 °C, melting curve analysis of the amplification product was carried out. The distinct mean melting temperature allowed simultaneous differentiation of the two target bacteria in the m-PSR assay. The limit of detection of S. typhimurium and S. aureus that could be detected simultaneously was 4.1 × 10-4 ng genomic DNA and 2 × 101 CFU/mL pure bacterial culture. Based on this method, analysis of artificially contaminated samples showed excellent sensitivity and specificity consistent with those of pure bacterial cultures. This method is rapid, simultaneous and promises to be a useful tool for the detection of food-borne pathogens in the food industry.
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Affiliation(s)
- Caihong Yin
- Department of Hygienic Inspection, School of Public Health, Jilin University, Changchun, 130021, PR China
| | - Bo Pang
- Department of Hygienic Inspection, School of Public Health, Jilin University, Changchun, 130021, PR China
| | - Yanzhi Huang
- Research Laboratory, Changchun Children's Hospital, Changchun, 130061, Jilin, PR China
| | - Jinhua Li
- Department of Hygienic Inspection, School of Public Health, Jilin University, Changchun, 130021, PR China
| | - Tingyu Meng
- Research Laboratory, Changchun Children's Hospital, Changchun, 130061, Jilin, PR China
| | - Mengfan Zhang
- Department of Hygienic Inspection, School of Public Health, Jilin University, Changchun, 130021, PR China.
| | - Liang Zhang
- Department of Hygienic Inspection, School of Public Health, Jilin University, Changchun, 130021, PR China
| | - Yanli Gao
- Department of Pediatric Ultrasound, The First Hospital of Jilin University, Changchun, 130000, PR China.
| | - Xiuling Song
- Department of Hygienic Inspection, School of Public Health, Jilin University, Changchun, 130021, PR China.
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Sharma M, Singh P. Advances in the Diagnosis of Leprosy. FRONTIERS IN TROPICAL DISEASES 2022. [DOI: 10.3389/fitd.2022.893653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Leprosy is a public health issue, and early detection is critical to avert disability. Despite the global attempt to eradicate this disease as a public health problem, it remains an important cause of global neurological disability. India, Brazil and Indonesia share more than 70% of the cases. The reduction of new cases is a priority in the WHO global strategy 2021-2030 which aims to reduce disease transmission in the community by diagnosing cases and identifying subclinical infection. The clinical manifestations of leprosy range from a few to several lesions. The identification remains difficult due to the limited sensitivity of traditional approaches based on bacillary counts of skin smears and histology. To aid in the diagnosis of this disease, molecular biology, and biotechnological technologies have been applied, each with its own set of benefits and downsides despite providing an essential tool to validate the clinical diagnosis of leprosy. Because of this, it is strongly recognized that specific, inexpensive point of care technologies should be developed, particularly to identify asymptomatic M. leprae infections or leprosy nearer to the suspected cases seeking medical attention. Thus, this review will provide an overview of the advancements in leprosy diagnosis over the world. The purpose of this review is to improve our understanding of the outcomes of current tests and technologies used in leprosy diagnosis and to emphasize critical aspects concerning the detection of leprosy bacilli.
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Sereno D, Oury B, Geiger A, Vela A, Karmaoui A, Desquesnes M. Isothermal Nucleic Acid Amplification to Detect Infection Caused by Parasites of the Trypanosomatidae Family: A Literature Review and Opinion on the Laboratory to Field Applicability. Int J Mol Sci 2022; 23:ijms23147543. [PMID: 35886895 PMCID: PMC9322063 DOI: 10.3390/ijms23147543] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/03/2022] [Accepted: 07/04/2022] [Indexed: 12/13/2022] Open
Abstract
Isothermal amplification of nucleic acids has the potential to be applied in resource-limited areas for the detection of infectious agents, as it does not require complex nucleic purification steps or specific and expensive equipment and reagents to perform the reaction and read the result. Since human and animal infections by pathogens of the Tryponasomatidae family occur mainly in resource-limited areas with scant health infrastructures and personnel, detecting infections by these methodologies would hold great promise. Here, we conduct a narrative review of the literature on the application of isothermal nucleic acid amplification for Trypanosoma and Leishmania infections, which are a scourge for human health and food security. We highlight gaps and propose ways to improve them to translate these powerful technologies into real-world field applications for neglected human and animal diseases caused by Trypanosomatidae.
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Affiliation(s)
- Denis Sereno
- Institut de Recherche pour le Développement, Université de Montpellier, UMR INTERTRYP IRD, CIRAD, Parasite Infectiology and Public Health Group, 34032 Montpellier, France;
- Correspondence:
| | - Bruno Oury
- Institut de Recherche pour le Développement, Université de Montpellier, UMR INTERTRYP IRD, CIRAD, Parasite Infectiology and Public Health Group, 34032 Montpellier, France;
| | - Anne Geiger
- Centre International de Recherche en Agronomie pour le Développement, Institut de Recherche pour le Développement, Université de Montpellier, UMR INTERTRYP IRD, 34032 Montpellier, France;
| | - Andrea Vela
- One Health Research Group, Facultad de Ciencias de la Salud, Universidad de las Américas-Quito, Calle de los Colimes y Avenida De los Granados, Quito 170513, Ecuador;
| | - Ahmed Karmaoui
- Bioactives (Health and Environmental, Epigenetics Team), Faculty of Sciences and Techniques, Errachidia (UMI), Moroccan Center for Culture and Sciences, University Moulay Ismail, Meknes 50000, Morocco;
| | - Marc Desquesnes
- CIRAD, UMR INTERTRYP, 31076 Toulouse, France;
- INTERTRYP, Université de Montpellier, CIRAD, IRD, 34032 Montpellier, France
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Saar M, Beissner M, Gültekin F, Maman I, Herbinger KH, Bretzel G. RLEP LAMP for the laboratory confirmation of leprosy: towards a point-of-care test. BMC Infect Dis 2021; 21:1186. [PMID: 34823479 PMCID: PMC8620619 DOI: 10.1186/s12879-021-06882-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 11/02/2021] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Nucleic acid-based amplification tests (NAAT), above all (q)PCR, have been applied for the detection of Mycobacterium leprae in leprosy cases and household contacts with subclinical infection. However, their application in the field poses a range of technical challenges. Loop-mediated isothermal amplification (LAMP), as a promising point-of-care NAAT does not require sophisticated laboratory equipment, is easy to perform, and is applicable for decentralized diagnosis at the primary health care level. Among a range of gene targets, the M. leprae specific repetitive element RLEP is regarded as highly sensitive and specific for diagnostic applications. METHODS: Our group developed and validated a dry-reagent-based (DRB) RLEP LAMP, provided product specifications for customization of a ready-to-use kit (intended for commercial production) and compared it against the in-house prototype. The assays were optimized for application on a Genie® III portable fluorometer. For technical validation, 40 "must not detect RLEP" samples derived from RLEP qPCR negative exposed and non-exposed individuals, as well as from patients with other conditions and a set of closely related mycobacterial cultures, were tested together with 25 "must detect RLEP" samples derived from qPCR confirmed leprosy patients. For clinical validation, 150 RLEP qPCR tested samples were analyzed, consisting of the following categories: high-positive samples of multibacillary (MB) leprosy patients (> 10.000 bacilli/extract), medium-positive samples of MB leprosy patients (1.001-10.000 bacilli/extract), low-positive samples of MB leprosy patients (1-1.000 bacilli/extract), endemic controls and healthy non-exposed controls; each n = 30. RESULTS: Technical validation: both LAMP formats had a limit of detection of 1.000 RLEP copies, i.e. 43-27 bacilli, a sensitivity of 92% (in-house protocol)/100% (ready-to-use protocol) and a specificity of 100%. Reagents were stable for at least 1 year at 22 °C. Clinical validation: Both formats showed a negativity rate of 100% and a positivity rate of 100% for high-positive samples and 93-100% for medium positive samples, together with a positive predictive value of 100% and semi-quantitative results. The positivity rate for low-positive samples was 77% (in-house protocol)/43% (ready-to-use protocol) and differed significantly between both formats. CONCLUSIONS: The ready-to-use RLEP DRB LAMP assay constitutes an ASSURED test ready for field-based evaluation trials aiming for routine diagnosis of leprosy at the primary health care level.
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Affiliation(s)
- Malkin Saar
- Division of Infectious Diseases and Tropical Medicine, University Hospital, Ludwig-Maximilians-University (LMU) Munich, Leopoldstrasse 5, 80802, Munich, Germany.
| | - Marcus Beissner
- Division of Infectious Diseases and Tropical Medicine, University Hospital, Ludwig-Maximilians-University (LMU) Munich, Leopoldstrasse 5, 80802, Munich, Germany
| | - Fatih Gültekin
- Division of Infectious Diseases and Tropical Medicine, University Hospital, Ludwig-Maximilians-University (LMU) Munich, Leopoldstrasse 5, 80802, Munich, Germany
| | - Issaka Maman
- Ministère de la Santé, Institut National d'Hygiène (INH), Lomé, Togo
| | - Karl-Heinz Herbinger
- Division of Infectious Diseases and Tropical Medicine, University Hospital, Ludwig-Maximilians-University (LMU) Munich, Leopoldstrasse 5, 80802, Munich, Germany
| | - Gisela Bretzel
- Division of Infectious Diseases and Tropical Medicine, University Hospital, Ludwig-Maximilians-University (LMU) Munich, Leopoldstrasse 5, 80802, Munich, Germany
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