1
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Zhao D, Lu Y, Zong H, Cao X, Lu M, Tang C, Zhou Y, Li K, Xiao J. Rapid Real-Time PCR Based on Core-Shell Tecto-Dendrimer-Entrapped Au Nanoparticles. ACS Biomater Sci Eng 2024. [PMID: 39233659 DOI: 10.1021/acsbiomaterials.4c01089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2024]
Abstract
Rapid real-time PCR (generally <1 h) has broad prospects. In this study, we synthesized a new type of nanomaterial core-shell tecto-dendrimer coated with Au nanoparticles (Au CSTDs) for research in this field. The experimental results showed that Au CSTDs could significantly shorten the time of real-time PCR (from 72 to 28 min) with different templates, while the detection limit reached 10 copies and the nonspecific amplification was significantly reduced. Furthermore, experimental analyses and theoretical studies using the finite element simulation method confirmed that Au CSTDs function by synergistically enhancing electrostatic adsorption and thermal conductivity. These properties play a key role in improving real-time PCR, especially in particle-particle interactions. This study contributes an advanced method to rapid real-time PCR, which is expected to remarkably improve the efficiency, lower the detection limit, and enhance the specificity of molecular detection.
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Affiliation(s)
- Dongqing Zhao
- College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, China
| | - Yao Lu
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
| | - Huanhuan Zong
- College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, China
| | - Xueyan Cao
- College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, China
| | - Meng Lu
- College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, China
| | - Chen Tang
- College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, China
| | - Yuxun Zhou
- College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, China
| | - Kai Li
- College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, China
| | - Junhua Xiao
- College of Biological Science and Medical Engineering, Donghua University, Shanghai 201620, China
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2
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Mears MC, Olivier TL, Williams-Coplin D, Espinoza E, Bakre A. Detection and differentiation of low virulence and virulent Orthoavulavirus javaense using a molecular beacon with RT-LAMP. Sci Rep 2024; 14:18047. [PMID: 39103419 PMCID: PMC11300668 DOI: 10.1038/s41598-024-68816-7] [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: 03/09/2024] [Accepted: 07/29/2024] [Indexed: 08/07/2024] Open
Abstract
Newcastle disease (ND), an economically important disease in poultry, is caused by virulent strains of the genetically diverse Orthoavulavirus javaense (OAVJ). Laboratories rely on quantitative real-time reverse transcription PCR (qRT-PCR) to detect OAVJ and differentiate between OAVJ pathotypes. This study demonstrates that a fusion cleavage site based molecular beacon with reverse transcription loop mediated isothermal amplification (MB-RT-LAMP) assay can detect and differentiate OAVJ pathotypes in a single assay. Data show that the assay can rapidly identify diverse OAVJ genotypes with sensitivity only one log-fold lower than the current fusion qRT-PCR assay (104 copies), exhibits a high degree of specificity for OAVJ, and the molecular beacon can differentiate mesogenic/velogenic sequences from lentogenic sequences. Further, data show that a two-minute rapid lysis protocol preceding MB-RT-LAMP can detect and differentiate OAVJ RNA from both spiked samples and oropharyngeal swabs without the need for RNA isolation. As the MB-RT-LAMP assay can rapidly detect and discriminate between lentogenic and mesogenic/velogenic sequences of OAVJ within one assay, without the need for RNA isolation, and is adaptable to existing veterinary diagnostic laboratory workflow without additional equipment, this assay could be a rapid primary screening tool before qRT-PCR based validation in resource limited settings.
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Affiliation(s)
- Megan C Mears
- Exotic and Emerging Avian Viral Disease Research Unit, Southeast Poultry Research Laboratories, US National Poultry Research Center, 934 College Station Road, Athens, GA, 30605, USA
| | - Timothy L Olivier
- Exotic and Emerging Avian Viral Disease Research Unit, Southeast Poultry Research Laboratories, US National Poultry Research Center, 934 College Station Road, Athens, GA, 30605, USA
| | - Dawn Williams-Coplin
- Exotic and Emerging Avian Viral Disease Research Unit, Southeast Poultry Research Laboratories, US National Poultry Research Center, 934 College Station Road, Athens, GA, 30605, USA
| | - Edna Espinoza
- Exotic and Emerging Avian Viral Disease Research Unit, Southeast Poultry Research Laboratories, US National Poultry Research Center, 934 College Station Road, Athens, GA, 30605, USA
| | - Abhijeet Bakre
- Exotic and Emerging Avian Viral Disease Research Unit, Southeast Poultry Research Laboratories, US National Poultry Research Center, 934 College Station Road, Athens, GA, 30605, USA.
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3
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El-Tholoth M, Bau HH. Molecular Detection of Respiratory Tract Viruses in Chickens at the Point of Need by Loop-Mediated Isothermal Amplification (LAMP). Viruses 2024; 16:1248. [PMID: 39205222 PMCID: PMC11359210 DOI: 10.3390/v16081248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2024] [Revised: 07/27/2024] [Accepted: 08/02/2024] [Indexed: 09/04/2024] Open
Abstract
Accurate and timely molecular diagnosis of respiratory diseases in chickens is essential for implementing effective control measures, preventing the spread of diseases within poultry flocks, minimizing economic loss, and guarding food security. Traditional molecular diagnostic methods like polymerase chain reaction (PCR) require expensive equipment and trained personnel, limiting their use to centralized labs with a significant delay between sample collection and results. Loop-mediated isothermal amplification (LAMP) of nucleic acids offers an attractive alternative for detecting respiratory viruses in broiler chickens with sensitivity comparable to that of PCR. LAMP's main advantages over PCR are its constant incubation temperature (∼65 °C), high amplification efficiency, and contaminant tolerance, which reduce equipment complexity, cost, and power consumption and enable instrument-free tests. This review highlights effective LAMP methods and variants that have been developed for detecting respiratory viruses in chickens at the point of need.
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Affiliation(s)
- Mohamed El-Tholoth
- Department of Virology, Faculty of Veterinary Medicine, Mansoura University, Mansoura 35516, Egypt
- Veterinary Sciences Program, Health Sciences Division, Al Ain Men’s Campus, Higher Colleges of Technology, Al Ain 17155, United Arab Emirates
| | - Haim H. Bau
- Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, PA 19104, USA;
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4
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Yan Z, Eshed A, Tang AA, Arevalos NR, Ticktin ZM, Chaudhary S, Ma D, McCutcheon G, Li Y, Wu K, Saha S, Alcantar-Fernandez J, Moreno-Camacho JL, Campos-Romero A, Collins JJ, Yin P, Green AA. Rapid, Multiplexed, and Enzyme-Free Nucleic Acid Detection Using Programmable Aptamer-Based RNA Switches. Chem 2024; 10:2220-2244. [PMID: 39036067 PMCID: PMC11259118 DOI: 10.1016/j.chempr.2024.03.015] [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] [Indexed: 07/23/2024]
Abstract
Rapid, simple, and low-cost diagnostic technologies are crucial tools for combatting infectious disease. We describe a class of aptamer-based RNA switches or aptaswitches that recognize target nucleic acid molecules and initiate folding of a reporter aptamer. Aptaswitches can detect virtually any sequence and provide an intense fluorescent readout without intervening enzymes, generating signals in as little as 5 minutes and enabling detection by eye with minimal equipment. Aptaswitches can be used to regulate folding of seven fluorogenic aptamers, providing a general means of controlling aptamers and an array of multiplexable reporter colors. Coupling isothermal amplification reactions with aptaswitches, we reach sensitivities down to 1 RNA copy/μL in one-pot reactions. Application of multiplexed all-in-one reactions against RNA from clinical saliva samples yields an overall accuracy of 96.67% for detection of SARS-CoV-2 in 30 minutes. Aptaswitches are thus versatile tools for nucleic acid detection that are readily integrated into rapid diagnostic assays.
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Affiliation(s)
- Zhaoqing Yan
- Department of Biomedical Engineering, Boston University,
Boston, MA, USA
- Molecular Biology, Cell Biology & Biochemistry Program,
Graduate School of Arts and Sciences, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA
02215, USA
| | - Amit Eshed
- Department of Biomedical Engineering, Boston University,
Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA
02215, USA
| | - Anli A. Tang
- Biodesign Center for Molecular Design and Biomimetics at
the Biodesign Institute, Arizona State University, Tempe, AZ, USA
- School of Molecular Sciences, Arizona State University,
Tempe, AZ, USA
| | - Nery R. Arevalos
- Department of Biomedical Engineering, Boston University,
Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA
02215, USA
| | - Zachary M. Ticktin
- Biodesign Center for Molecular Design and Biomimetics at
the Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - Soma Chaudhary
- Biodesign Center for Molecular Design and Biomimetics at
the Biodesign Institute, Arizona State University, Tempe, AZ, USA
- School of Molecular Sciences, Arizona State University,
Tempe, AZ, USA
| | - Duo Ma
- Biodesign Center for Molecular Design and Biomimetics at
the Biodesign Institute, Arizona State University, Tempe, AZ, USA
- School of Molecular Sciences, Arizona State University,
Tempe, AZ, USA
| | - Griffin McCutcheon
- Department of Biomedical Engineering, Boston University,
Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA
02215, USA
- Biodesign Center for Molecular Design and Biomimetics at
the Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - Yudan Li
- Molecular Biology, Cell Biology & Biochemistry Program,
Graduate School of Arts and Sciences, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA
02215, USA
| | - Kaiyue Wu
- Molecular Biology, Cell Biology & Biochemistry Program,
Graduate School of Arts and Sciences, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA
02215, USA
| | - Sanchari Saha
- Biodesign Center for Molecular Design and Biomimetics at
the Biodesign Institute, Arizona State University, Tempe, AZ, USA
- School of Molecular Sciences, Arizona State University,
Tempe, AZ, USA
| | | | | | | | - James J. Collins
- Department of Biological Engineering, Massachusetts
Institute of Technology (MIT), Cambridge, MA, USA
- Institute for Medical Engineering and Science, MIT,
Cambridge, MA, USA
- Wyss Institute for Biologically Inspired Engineering,
Harvard University, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA,
USA
| | - Peng Yin
- Wyss Institute for Biologically Inspired Engineering,
Harvard University, Boston, MA, USA
- Department of Systems Biology, Harvard Medical School,
Boston, MA, USA
| | - Alexander A. Green
- Department of Biomedical Engineering, Boston University,
Boston, MA, USA
- Molecular Biology, Cell Biology & Biochemistry Program,
Graduate School of Arts and Sciences, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA
02215, USA
- School of Molecular Sciences, Arizona State University,
Tempe, AZ, USA
- Lead contact
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5
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Caffrey M, Jayakumar N, Caffrey V, Anirudhan V, Rong L, Paprotny I. VLP-based model for the study of airborne viral pathogens. Microbiol Spectr 2024; 12:e0001324. [PMID: 38752752 PMCID: PMC11237701 DOI: 10.1128/spectrum.00013-24] [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: 01/03/2024] [Accepted: 04/21/2024] [Indexed: 05/28/2024] Open
Abstract
The recent COVID-19 pandemic has underscored the danger of airborne viral pathogens. The lack of model systems to study airborne pathogens limits the understanding of airborne pathogen distribution as well as potential surveillance and mitigation strategies. In this work, we develop a novel model system to study airborne pathogens using virus-like particles (VLPs). Specifically, we demonstrate the ability to aerosolize VLP and detect and quantify aerosolized VLP RNA by reverse transcription-loop-mediated isothermal amplification in real-time fluorescent and colorimetric assays. Importantly, the VLP model presents many advantages for the study of airborne viral pathogens: (i) similarity in size and surface components; (ii) ease of generation and noninfectious nature enabling the study of biosafety level 3 and biosafety level 4 viruses; (iii) facile characterization of aerosolization parameters; (iv) ability to adapt the system to other viral envelope proteins, including those of newly discovered pathogens and mutant variants; and (v) the ability to introduce viral sequences to develop nucleic acid amplification assays. IMPORTANCE The study and detection of airborne pathogens are hampered by the lack of appropriate model systems. In this work, we demonstrate that noninfectious virus-like particles (VLPs) represent attractive models to study airborne viral pathogens. Specifically, VLPs are readily prepared, are similar in size and composition to infectious viruses, and are amenable to highly sensitive nucleic acid amplification techniques.
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Affiliation(s)
- Michael Caffrey
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Nitin Jayakumar
- Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Veronique Caffrey
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Varada Anirudhan
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Lijun Rong
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Igor Paprotny
- Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, Illinois, USA
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6
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Yuan Y, Ellis P, Tao Y, Bikos DA, Loveday EK, Thomas MM, Wilking JN, Chang CB, Ye F, Weitz DA. Digital droplet RT-LAMP increases speed of SARS-CoV-2 viral RNA detection. SMART MEDICINE 2024; 3:e20240008. [PMID: 39188696 PMCID: PMC11235653 DOI: 10.1002/smmd.20240008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Accepted: 04/27/2024] [Indexed: 08/28/2024]
Abstract
Nucleic acid amplification testing (NAAT) remains one of the most reliable methods for pathogen identification. However, conventional bulk NAATs may not be sufficiently fast or sensitive enough for the detection of clinically-relevant pathogens in point-of-care testing. Here, we have developed a digital droplet RT-LAMP (ddRT-LAMP) assay that rapidly and quantitatively detects the SARS-CoV-2 viral E gene in microfluidic drops. Droplet partitioning using ddRT-LAMP significantly accelerates detection times across a wide range of template concentrations compared to bulk RT-LAMP assays. We discover that a reduction in droplet diameter decreases assay times up to a certain size, upon which surface adsorption of the RT-LAMP polymerase reduces reaction efficiency. Optimization of drop size and polymerase concentration enables rapid, sensitive, and quantitative detection of the SARS-CoV-2 E gene in only 8 min. These results highlight the potential of ddRT-LAMP assays as an excellent platform for quantitative point-of-care testing.
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Affiliation(s)
- Yuan Yuan
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health)Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhouZhejiangChina
- John A. Paulson School of Engineering and Applied SciencesHarvard UniversityCambridgeMassachusettsUSA
| | - Perry Ellis
- John A. Paulson School of Engineering and Applied SciencesHarvard UniversityCambridgeMassachusettsUSA
| | - Ye Tao
- John A. Paulson School of Engineering and Applied SciencesHarvard UniversityCambridgeMassachusettsUSA
| | - Dimitri A. Bikos
- Department of Chemical and Biological EngineeringMontana State UniversityBozemanMontanaUSA
- Center for Biofilm EngineeringMontana State UniversityBozemanMontanaUSA
| | - Emma K. Loveday
- Department of Chemical and Biological EngineeringMontana State UniversityBozemanMontanaUSA
- Center for Biofilm EngineeringMontana State UniversityBozemanMontanaUSA
| | - Mallory M. Thomas
- Department of Chemical and Biological EngineeringMontana State UniversityBozemanMontanaUSA
- Center for Biofilm EngineeringMontana State UniversityBozemanMontanaUSA
| | - James N. Wilking
- Department of Chemical and Biological EngineeringMontana State UniversityBozemanMontanaUSA
- Center for Biofilm EngineeringMontana State UniversityBozemanMontanaUSA
- Department of Physiology and Biomedical EngineeringMayo ClinicRochesterMinnesotaUSA
| | - Connie B. Chang
- Department of Chemical and Biological EngineeringMontana State UniversityBozemanMontanaUSA
- Center for Biofilm EngineeringMontana State UniversityBozemanMontanaUSA
- Department of Physiology and Biomedical EngineeringMayo ClinicRochesterMinnesotaUSA
| | - Fangfu Ye
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health)Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhouZhejiangChina
- Beijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijingChina
| | - David A. Weitz
- John A. Paulson School of Engineering and Applied SciencesHarvard UniversityCambridgeMassachusettsUSA
- Department of PhysicsHarvard UniversityCambridgeMassachusettsUSA
- Wyss Institute for Biologically Inspired EngineeringHarvard UniversityBostonMassachusettsUSA
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7
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Wilkinson AF, Barra MJ, Novak EN, Bond M, Richards-Kortum R. Point-of-care isothermal nucleic acid amplification tests: progress and bottlenecks for extraction-free sample collection and preparation. Expert Rev Mol Diagn 2024; 24:509-524. [PMID: 38973430 DOI: 10.1080/14737159.2024.2375233] [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: 12/15/2023] [Accepted: 06/28/2024] [Indexed: 07/09/2024]
Abstract
INTRODUCTION Suitable sample collection and preparation methods are essential to enable nucleic acid amplification testing at the point of care (POC). Strategies that allow direct isothermal nucleic acid amplification testing (iNAAT) of crude sample lysate without the need for nucleic acid extraction minimize time to result as well as the need for operator expertise and costly infrastructure. AREAS COVERED The authors review research to understand how sample matrix and preparation affect the design and performance of POC iNAATs. They focus on approaches where samples are directly combined with liquid reagents for preparation and amplification via iNAAT strategies. They review factors related to the type and method of sample collection, storage buffers, and lysis strategies. Finally, they discuss RNA targets and relevant regulatory considerations. EXPERT OPINION Limitations in sample preparation methods are a significant technical barrier preventing implementation of nucleic acid testing at the POC. The authors propose a framework for co-designing sample preparation and amplification steps for optimal performance with an extraction-free paradigm by considering a sample matrix and lytic strategy prior to an amplification assay and readout. In the next 5 years, the authors anticipate increasing priority on the co-design of sample preparation and iNAATs.
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Affiliation(s)
| | - Maria J Barra
- Department of Bioengineering, Rice University, Houston, TX, USA
| | - Emilie N Novak
- Department of Bioengineering, Rice University, Houston, TX, USA
| | - Meaghan Bond
- Rice360 Institute for Global Health Technologies, Rice University, Houston, TX, USA
| | - Rebecca Richards-Kortum
- Department of Bioengineering, Rice University, Houston, TX, USA
- Rice360 Institute for Global Health Technologies, Rice University, Houston, TX, USA
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8
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Costa-Ribeiro A, Lamas A, Garrido-Maestu A. Evaluating Commercial Loop-Mediated Isothermal Amplification Master Mixes for Enhanced Detection of Foodborne Pathogens. Foods 2024; 13:1635. [PMID: 38890864 PMCID: PMC11172173 DOI: 10.3390/foods13111635] [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: 04/15/2024] [Revised: 05/22/2024] [Accepted: 05/23/2024] [Indexed: 06/20/2024] Open
Abstract
Loop-mediated isothermal amplification, LAMP, is nowadays the most popular isothermal nucleic acid amplification technique, and as such, several commercial, ready-to-use master mixes have flourished. Unfortunately, independent studies to determine their performance are limited. The current study performed an independent evaluation of the existing ready-to-use commercial LAMP master mixes WarmStart® LAMP Kit, LavaLAMP™ DNA Master Mix, Saphir Bst Turbo GreenMaster, OptiGene Fast Master Mix ISO-004, and SynLAMP Mix. To reduce bias, three different genes, namely ttr (Salmonella spp.), rfbE (E. coli O157), and hly (Listeria monocytogenes), were targeted. The comparison was based on amplification speed, performance with decreasing DNA concentrations, and the effect of five typical LAMP reaction additives (betaine, DMSO, pullulan, TMAC, and GuHCl). Significant differences were observed among the different master mixes. OptiGene provided the fastest amplification and showed less detrimental effects associated with the supplements evaluated. Out of the chemicals tested, pullulan provided the best results in terms of amplification speed. It is noteworthy that the different additives impacted the master mixes differently. Overall, the current study provides insights into the performance of commercial LAMP master mixes, which can be of value for the scientific community to better select appropriate reagents when developing new methods.
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Affiliation(s)
- Ana Costa-Ribeiro
- International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330 Braga, Portugal;
- Department of Biochemistry, Genetics and Immunology, University of Vigo, 36310 Vigo, Spain
| | - Alexandre Lamas
- Food Hygiene, Inspection and Control Laboratory (Lhica), Department of Analytical Chemistry, Nutrition and Bromatology, Veterinary School, Campus Terra, University of Santiago de Compostela (USC), 27002 Lugo, Spain;
| | - Alejandro Garrido-Maestu
- International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330 Braga, Portugal;
- Laboratory of Microbiology and Technology of Marine Products (MicroTEC), Instituto de Investigaciones Marinas (IIM), CSIC, Eduardo Cabello, 6, 36208 Vigo, Spain
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9
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Prado NO, Marin AM, Lalli LA, Sanchuki HBS, Wosniaki DK, Nardin JM, Morales HMP, Blanes L, Zanette DL, Aoki MN. Development and evaluation of a lyophilization protocol for colorimetric RT-LAMP diagnostic assay for COVID-19. Sci Rep 2024; 14:10612. [PMID: 38719936 PMCID: PMC11078981 DOI: 10.1038/s41598-024-61163-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Accepted: 05/02/2024] [Indexed: 05/12/2024] Open
Abstract
Molecular diagnostics involving nucleic acids (DNA and RNA) are regarded as extremely functional tools. During the 2020 global health crisis, efforts intensified to optimize the production and delivery of molecular diagnostic kits for detecting SARS-CoV-2. During this period, RT-LAMP emerged as a significant focus. However, the thermolability of the reagents used in this technique necessitates special low-temperature infrastructure for transport, storage, and conservation. These requirements limit distribution capacity and necessitate cost-increasing adaptations. Consequently, this report details the development of a lyophilization protocol for reagents in a colorimetric RT-LAMP diagnostic kit to detect SARS-CoV-2, facilitating room-temperature transport and storage. We conducted tests to identify the ideal excipients that maintain the molecular integrity of the reagents and ensure their stability during room-temperature storage and transport. The optimal condition identified involved adding 5% PEG 8000 and 75 mM trehalose to the RT-LAMP reaction, which enabled stability at room temperature for up to 28 days and yielded an analytical and diagnostic sensitivity and specificity of 83.33% and 90%, respectively, for detecting SARS-CoV-2. This study presents the results of a lyophilized colorimetric RT-LAMP COVID-19 detection assay with diagnostic sensitivity and specificity comparable to RT-qPCR, particularly in samples with high viral load.
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Affiliation(s)
- Nayra Oliveira Prado
- Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz), Prof. Algacyr Munhoz Mader 3775 Street, Curitiba, 81350-010, Brazil
| | - Anelis Maria Marin
- Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz), Prof. Algacyr Munhoz Mader 3775 Street, Curitiba, 81350-010, Brazil
| | - Larissa Araujo Lalli
- Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz), Prof. Algacyr Munhoz Mader 3775 Street, Curitiba, 81350-010, Brazil
| | - Heloisa Bruna Soligo Sanchuki
- Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz), Prof. Algacyr Munhoz Mader 3775 Street, Curitiba, 81350-010, Brazil
| | - Denise Kusma Wosniaki
- Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz), Prof. Algacyr Munhoz Mader 3775 Street, Curitiba, 81350-010, Brazil
| | - Jeanine Marie Nardin
- Erasto Gaertner Hospital, Dr. Ovande Do Amaral 201 Street, Curitiba, Paraná, 81520-060, Brazil
| | - Hugo Manoel Paz Morales
- Erasto Gaertner Hospital, Dr. Ovande Do Amaral 201 Street, Curitiba, Paraná, 81520-060, Brazil
| | - Lucas Blanes
- Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz), Prof. Algacyr Munhoz Mader 3775 Street, Curitiba, 81350-010, Brazil
| | - Dalila Luciola Zanette
- Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz), Prof. Algacyr Munhoz Mader 3775 Street, Curitiba, 81350-010, Brazil
| | - Mateus Nóbrega Aoki
- Laboratory for Applied Science and Technology in Health, Carlos Chagas Institute, Oswaldo Cruz Foundation (Fiocruz), Prof. Algacyr Munhoz Mader 3775 Street, Curitiba, 81350-010, Brazil.
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10
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Barra M, Chang M, Salcedo MP, Schmeler K, Scheurer M, Maza M, Lopez L, Alfaro K, Richards-Kortum R. Single-tube four-target lateral flow assay detects human papillomavirus types associated with majority of cervical cancers. Anal Biochem 2024; 688:115480. [PMID: 38331373 DOI: 10.1016/j.ab.2024.115480] [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: 12/20/2023] [Revised: 02/02/2024] [Accepted: 02/05/2024] [Indexed: 02/10/2024]
Abstract
Isothermal nucleic acid amplification methods have many advantages for use at the point of care. However, there is a lack of multiplexed isothermal amplification tests to detect multiple targets in a single reaction, which would be valuable for many diseases, such as infection with high-risk human papillomavirus (hrHPV). In this study, we developed a multiplexed loop-mediated isothermal amplification (LAMP) reaction to detect the three most common hrHPV types that cause cervical cancer (HPV16, HPV18, and HPV45) and a cellular control for sample adequacy. First, we characterized the assay limit of detection (LOD) in a real-time reaction with fluorescence readout; after 30 min of amplification the LOD was 100, 10, and 10 copies/reaction of HPV16, HPV18, and HPV45, respectively, and 0.1 ng/reaction of human genomic DNA (gDNA). Next, we implemented the assay on lateral flow strips, and the LOD was maintained for HPV16 and HPV18, but increased to 100 copies/reaction for HPV45 and to 1 ng/reaction for gDNA. Lastly, we used the LAMP test to evaluate total nucleic acid extracted from 38 clinical samples; compared to qPCR, the LAMP test had 89% sensitivity and 95% specificity. When integrated with sample preparation, this multiplexed LAMP assay could be useful for point-of-care testing.
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Affiliation(s)
- Maria Barra
- Department of Bioengineering, Rice University, Houston, TX, USA
| | - Megan Chang
- Department of Bioengineering, Rice University, Houston, TX, USA
| | - Mila P Salcedo
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Kathleen Schmeler
- Department of Gynecologic Oncology & Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Michael Scheurer
- Department of Pediatrics Hematology/Oncology, Baylor College of Medicine, Houston, TX, USA
| | - Mauricio Maza
- Basic Health International, San Salvador, El Salvador
| | - Leticia Lopez
- Basic Health International, San Salvador, El Salvador
| | - Karla Alfaro
- Basic Health International, San Salvador, El Salvador
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11
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Pirolo M, Menezes M, Poulsen M, Søndergaard V, Damborg P, Poirier AC, La Ragione R, Schjærff M, Guardabassi L. A LAMP point-of-care test to guide antimicrobial choice for treatment of Staphylococcus pseudintermedius pyoderma in dogs. Vet J 2024; 304:106105. [PMID: 38547963 DOI: 10.1016/j.tvjl.2024.106105] [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: 01/10/2024] [Revised: 03/22/2024] [Accepted: 03/22/2024] [Indexed: 04/16/2024]
Abstract
Staphylococcus pseudintermedius is the most common cause of pyoderma in dogs. We validated a point-of-care (PoC) test based on colorimetric loop-mediated isothermal amplification (LAMP) for rapid S. pseudintermedius identification and susceptibility testing for first line antimicrobials for systemic treatment of canine pyoderma, i.e., lincosamides, first generation cephalosporins and amoxicillin clavulanate. Newly designed LAMP primers targeting clinically relevant resistance genes were combined with a previously validated set of primers targeting spsL for species identification. After laboratory validation on 110 clinical isolates, we assessed the performance of the test on 101 clinical specimens using routine culture and susceptibility testing as a reference standard. The average hands-on and turnaround times for the PoC test were 30 and 90 min, respectively. The assay showed sensitivity and specificity near 100% for both species identification and susceptibility testing when performed on bacterial cultures or clinical specimens in the laboratory. However, the PoC test yielded less accurate results when performed on-site by clinical staff (92% sensitivity and 64% specificity for species identification, 67% sensitivity and 96% specificity for β-lactam susceptibility, and 83% sensitivity and 71% specificity for lincosamide susceptibility). These results indicate that the PoC test should be adapted to a user-friendly technology to facilitate performance and interpretation of results by clinical staff. If properly developed, the test would allow veterinarians to gain rapid information on antimicrobial choice, limiting the risk of treatment failure and facilitating adherence to antimicrobial use guidelines in small animal veterinary dermatology.
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Affiliation(s)
- M Pirolo
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg C 1870, Denmark
| | - M Menezes
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg C 1870, Denmark
| | - M Poulsen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg C 1870, Denmark
| | - V Søndergaard
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg C 1870, Denmark
| | - P Damborg
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg C 1870, Denmark
| | - A C Poirier
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, University of Surrey, Guildford GU2 7AL, UK
| | - R La Ragione
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, University of Surrey, Guildford GU2 7AL, UK; Department of Microbial Sciences, School of Biosciences, University of Surrey, Guildford GU2 7XH, UK
| | - M Schjærff
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg C, Denmark
| | - L Guardabassi
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg C 1870, Denmark.
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12
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Hong S, Park J, Bok J, Cho E, Rhee J. Assessment of measurement accuracy of amplified DNA using a colorimetric loop-mediated isothermal amplification assay. Biotechniques 2024; 76:114-118. [PMID: 38131320 DOI: 10.2144/btn-2023-0104] [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] [Indexed: 12/23/2023] Open
Abstract
A colorimetric loop-mediated isothermal amplification assay detects changes in pH during amplification based on color changes at a constant temperature. Currently, various studies have focused on developing and assessing molecular point-of-care testing instruments. In this study, we evaluated amplified DNA concentrations measured using the colorimetric LAMP assay of the 1POT™ Professional device (1drop Inc, Korea). Results of the 1POT analysis of clinical samples were compared with measurements obtained from the Qubit™ 4 and NanoDrop™ 2000 devices (both from Thermo Fisher Scientific, MA, USA). These results showed a correlation of 0.98 (95% CI: 0.96-0.99) and 0.96 (95% CI: 0.92-0.98) between 1POT and the Qubit and NanoDrop. 1POT can measure amplified DNA accurately and is suitable for on-site molecular diagnostics.
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Affiliation(s)
- Seongsoo Hong
- 1drop Inc, 215, Galmachi-ro, Jungwon-gu, Seongnam-si, Gyeonggi-do, Korea
| | - Jeongho Park
- 1drop Inc, 215, Galmachi-ro, Jungwon-gu, Seongnam-si, Gyeonggi-do, Korea
| | - Jaekyung Bok
- 1drop Inc, 215, Galmachi-ro, Jungwon-gu, Seongnam-si, Gyeonggi-do, Korea
| | - Euna Cho
- 1drop Inc, 215, Galmachi-ro, Jungwon-gu, Seongnam-si, Gyeonggi-do, Korea
| | - Joowon Rhee
- 1drop Inc, 215, Galmachi-ro, Jungwon-gu, Seongnam-si, Gyeonggi-do, Korea
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13
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Sritong N, Ngo WW, Ejendal KFK, Linnes JC. Development of an integrated sample amplification control for salivary point-of-care pathogen testing. Anal Chim Acta 2024; 1287:342072. [PMID: 38182338 DOI: 10.1016/j.aca.2023.342072] [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: 10/03/2023] [Revised: 11/20/2023] [Accepted: 11/25/2023] [Indexed: 01/07/2024]
Abstract
BACKGROUND The COVID-19 pandemic has led to a rise in point-of-care (POC) and home-based tests, but concerns over usability, accuracy, and effectiveness have arisen. The incorporation of internal amplification controls (IACs), essential control for translational POC diagnostics, could mitigate false-negative and false-positive results due to sample matrix interference or inhibition. Although emerging POC nucleic acid amplification tests (NAATs) for detecting SARS-CoV-2 show impressive analytical sensitivity in the lab, the assessment of clinical accuracy with IACs is often overlooked. In some cases, the IACs were run spatially, complicating assay workflow. Therefore, the multiplex assay for pathogen and IAC is needed. RESULTS We developed a one-pot duplex reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assay for saliva samples, a non-invasive and simple collected specimen for POC NAATs. The ORF1ab gene of SARS-CoV-2 was used as a target and a human 18S ribosomal RNA in human saliva was employed as an IAC to ensure clinical reliability of the RT-LAMP assay. The optimized assay could detect SARS-CoV-2 viral particles down to 100 copies/μL of saliva within 30 min without RNA extraction. The duplex RT-LAMP for SARS-CoV-2 and IAC is successfully amplified in the same reaction without cross-reactivity. The valid results were easily visualized in triple-line lateral flow immunoassay, in which two lines (flow control and IAC lines) represent valid negative results and three lines (flow control, IAC, and test line) represent valid positive results. This duplex assay demonstrated a clinical sensitivity of 95%, specificity of 100%, and accuracy of 96% in 30 clinical saliva samples. SIGNIFICANCE IACs play a crucial role in ensuring user confidence with respect to the accuracy and reliability of at-home and POC molecular diagnostics. We demonstrated the multiplex capability of SARS-COV-2 and human18S ribosomal RNA RT-LAMP without complicating assay design. This generic platform can be extended in a similar manner to include human18S ribosomal RNA IACs into different clinical sample matrices.
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Affiliation(s)
- Navaporn Sritong
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Winston Wei Ngo
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Karin F K Ejendal
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Jacqueline C Linnes
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA; Department of Public Health, Purdue University, West Lafayette, IN, USA.
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14
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Akter J, Smith WJM, Gebrewold M, Kim I, Simpson SL, Bivins A, Ahmed W. Evaluation of colorimetric RT-LAMP for screening of SARS-CoV-2 in untreated wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167964. [PMID: 37865239 DOI: 10.1016/j.scitotenv.2023.167964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 10/16/2023] [Accepted: 10/18/2023] [Indexed: 10/23/2023]
Abstract
This study compared reverse transcription-loop-mediated isothermal amplification (RT-LAMP) and three reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assays targeting the N and E genes of the SARS-CoV-2 genome for detecting RNA in untreated wastewater samples. RT-qPCR assays exhibited consistent amplification down to 2 × 102 GC/reaction, with greater analytical sensitivity at 2 × 101 GC/reaction by US CDC N1 and US CDC N2 assays. In contrast, RT-LAMP exhibited lower sensitivity, detecting SARS-CoV-2 only at or above 2 × 103 GC/reaction. For SARS-CoV-2 seeded wastewater samples, the US CDC N1 assay exhibited greater analytical sensitivity than the US CDC N2, E_Sarbeco, and RT-LAMP assays. Out of 30 wastewater samples, RT-qPCR detected endogenous SARS-CoV-2 RNA in 29 samples, while RT-LAMP identified 27 positive samples, with 20 displaying consistent amplifications in all three RT-LAMP technical replicates. Agreement analysis revealed a strong concordance between RT-LAMP and the US CDC N1 and E_Sarbeco RT-qPCR assays (κ = 0.474) but lower agreement with the US CDC N2 RT-qPCR assay (κ = 0.359). Quantification of SARS-CoV-2 RNA in positive samples revealed a strong correlation between the US CDC N1 and E_Sarbeco assays, while the US CDC N1 and US CDC N2 assays exhibited weak correlation. Logistic regression analysis indicated that RT-LAMP results correlated with RNA quantified by the US CDC N1 and E_Sarbeco assays, with 95 % limits of detection of 3.99 and 3.47 log10 GC/15 mL, respectively. In conclusion, despite lower sensitivity compared to RT-qPCR assays, RT-LAMP may offer advantages for wastewater surveillance, such as rapid results (estimated as twice as fast), and simplicity, making it a valuable tool in the shifting landscape of COVID-19 wastewater surveillance. Furthermore, LAMP positive wastewater samples might be prioritized for SARS-CoV-2 sequencing due to reduced analytical sensitivity. These findings support the use of RT-LAMP as a specific and efficient method for screening wastewater samples for SARS-CoV-2, particularly in resource-limited settings.
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Affiliation(s)
- Jesmin Akter
- Department of Civil and Environmental Engineering, University of Science and Technology, Republic of Korea; Department of Environmental Research, Korea Institute of Civil Engineering and Building Technology (KICT), Republic of Korea; CSIRO Environment, Ecosciences Precinct, 41 Boggo Road, Dutton Park, QLD 4102, Australia
| | - Wendy J M Smith
- CSIRO Environment, Ecosciences Precinct, 41 Boggo Road, Dutton Park, QLD 4102, Australia
| | - Metasebia Gebrewold
- CSIRO Environment, Ecosciences Precinct, 41 Boggo Road, Dutton Park, QLD 4102, Australia
| | - Ilho Kim
- Department of Civil and Environmental Engineering, University of Science and Technology, Republic of Korea; Department of Environmental Research, Korea Institute of Civil Engineering and Building Technology (KICT), Republic of Korea
| | | | - Aaron Bivins
- Department of Civil & Environmental Engineering, Louisiana State University, Baton Rouge, LA 70803, United States of America
| | - Warish Ahmed
- CSIRO Environment, Ecosciences Precinct, 41 Boggo Road, Dutton Park, QLD 4102, Australia.
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15
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Caffrey M, Jayakumar N, Caffrey V, Anirudan V, Rong L, Paprotny I. VLP-Based Model for Study of Airborne Viral Pathogens. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.03.574055. [PMID: 38260552 PMCID: PMC10802359 DOI: 10.1101/2024.01.03.574055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The recent COVID-19 pandemic has underscored the danger of airborne viral pathogens. The lack of model systems to study airborne pathogens limits the understanding of airborne pathogen distribution, as well as potential surveillance and mitigation strategies. In this work, we develop a novel model system to study airborne pathogens using virus like particles (VLP). Specifically, we demonstrate the ability to aerosolize VLP and detect and quantify aerosolized VLP RNA by Reverse Transcription-Loop-Mediated Isothermal Amplification (RT-LAMP) in real-time fluorescent and colorimetric assays. Importantly, the VLP model presents many advantages for the study of airborne viral pathogens: (i) similarity in size and surface components; (ii) ease of generation and noninfectious nature enabling study of BSL3 and BSL4 viruses; (iii) facile characterization of aerosolization parameters; (iv) ability to adapt the system to other viral envelope proteins including those of newly discovered pathogens and mutant variants; (v) the ability to introduce viral sequences to develop nucleic acid amplification assays.
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Affiliation(s)
- Michael Caffrey
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60607
| | - Nitin Jayakumar
- Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, IL 60607
| | - Veronique Caffrey
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60607
| | - Varada Anirudan
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612
| | - Lijun Rong
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612
| | - Igor Paprotny
- Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, IL 60607
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16
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Amaral C, Pimentel C. Direct Detection of SARS-CoV-2 RNA in Saliva with Colorimetric RT-LAMP. Methods Mol Biol 2024; 2822:39-50. [PMID: 38907910 DOI: 10.1007/978-1-0716-3918-4_4] [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] [Indexed: 06/24/2024]
Abstract
RT-LAMP is an effective alternative to RT-PCR-based diagnostics, offering high specificity, sensitivity, and rapid results. One notable advantage is the robustness of its enzymes, allowing for direct amplification from crude samples without the need for prior isolation of RNA. Colorimetric LAMP is particularly attractive as it eliminates the need for complex instrumentation, making it suitable for point-of-care applications. Here, we present a comprehensive step-by-step protocol for establishing an RT-LAMP-based test for direct detection of SARS-CoV-2 genomic RNA in saliva samples using different colorimetric detection methods. Importantly, this versatile test can be easily adapted to detect emerging pathogens.
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Affiliation(s)
- Catarina Amaral
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Catarina Pimentel
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal.
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17
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Mohammadi A, Chiang S, Li F, Wei F, Lau CS, Aziz M, Ibarrondo FJ, Fulcher JA, Yang OO, Chia D, Kim Y, Wong DT. Direct Detection of 4-Dimensions of SARS-CoV-2: Infection (vRNA), Infectivity (Antigen), Binding Antibody, and Functional Neutralizing Antibody in Saliva. RESEARCH SQUARE 2023:rs.3.rs-3745787. [PMID: 38234820 PMCID: PMC10793499 DOI: 10.21203/rs.3.rs-3745787/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
We developed a 4-parameter clinical assay using Electric Field Induced Release and Measurement (EFIRM) technology to simultaneously assess SARS-CoV-2 RNA (vRNA), nucleocapsid antigen, host binding (BAb) and neutralizing antibody (NAb) levels from a drop of saliva with performance that equals or surpasses current EUA-approved tests. The vRNA and antigen assays achieved lower limit of detection (LOD) of 100 copies/reaction and 3.5 TCID₅₀/mL, respectively. The vRNA assay differentiated between acutely infected (n=10) and infection-naïve patients (n=33) with an AUC of 0.9818, sensitivity of 90%, and specificity of 100%. The antigen assay similarly differentiated these patient populations with an AUC of 1.000. The BAb assay detected BAbs with an LOD of 39 pg/mL and distinguished acutely infected (n=35), vaccinated with prior infection (n=13), and vaccinated infection-naïve patients (n=13) from control (n=81) with AUC of 0.9481, 1.000, and 0.9962, respectively. The NAb assay detected NAbs with an LOD of 31.6 Unit/mL and differentiated between COVID-19 recovered or vaccinated patients (n=31) and pre-pandemic controls (n=60) with an AUC 0.923, sensitivity of 87.10%, and specificity of 86.67%. Our multiparameter assay represents a significant technological advancement to simultaneously address SARS-CoV-2 infection and immunity, and it lays the foundation for tackling potential future pandemics.
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Affiliation(s)
- Aida Mohammadi
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Samantha Chiang
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Feng Li
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Fang Wei
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | | | - Mohammad Aziz
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Francisco J. Ibarrondo
- Division of Infectious Diseases, Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Jennifer A. Fulcher
- Division of Infectious Diseases, Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Otto O. Yang
- Division of Infectious Diseases, Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - David Chia
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Yong Kim
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | - David T.W. Wong
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
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18
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Li Z, Sinha A, Zhang Y, Tanner N, Cheng HT, Premsrirut P, Carlow CKS. Extraction-free LAMP assays for generic detection of Old World Orthopoxviruses and specific detection of Mpox virus. Sci Rep 2023; 13:21093. [PMID: 38036581 PMCID: PMC10689478 DOI: 10.1038/s41598-023-48391-z] [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: 07/21/2023] [Accepted: 11/26/2023] [Indexed: 12/02/2023] Open
Abstract
Mpox is a neglected zoonotic disease endemic in West and Central Africa. The Mpox outbreak with more than 90,000 cases worldwide since 2022 generated great concern about future outbreaks and highlighted the need for a simple and rapid diagnostic test. The Mpox virus, MPV, is a member of the Orthopoxvirus (OPV) genus that also contains other pathogenic viruses including variola virus, vaccinia virus, camelpox virus, and cowpox virus. Phylogenomic analysis of 200 OPV genomes identified 10 distinct phylogroups with the New World OPVs placed on a very long branch distant from the Old World OPVs. Isolates derived from infected humans were found to be distributed across multiple phylogroups interspersed with isolates from animal sources, indicating the zoonotic potential of these viruses. In this study, we developed a simple and sensitive colorimetric LAMP assay for generic detection of Old World OPVs. We also developed an MPV-specific probe that differentiates MPV from other OPVs in the N1R LAMP assay. In addition, we described an extraction-free protocol for use directly with swab eluates in LAMP assays, thereby eliminating the time and resources needed to extract DNA from the sample. Our direct LAMP assays are well-suited for low-resource settings and provide a valuable tool for rapid and scalable diagnosis and surveillance of OPVs and MPV.
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Affiliation(s)
- Zhiru Li
- Molecular Genetics and Genomics Division, New England Biolabs, Ipswich, MA, 01938, USA.
| | - Amit Sinha
- Molecular Genetics and Genomics Division, New England Biolabs, Ipswich, MA, 01938, USA
| | - Yinhua Zhang
- Molecular Genetics and Genomics Division, New England Biolabs, Ipswich, MA, 01938, USA
| | - Nathan Tanner
- Molecular Genetics and Genomics Division, New England Biolabs, Ipswich, MA, 01938, USA
| | | | | | - Clotilde K S Carlow
- Molecular Genetics and Genomics Division, New England Biolabs, Ipswich, MA, 01938, USA
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19
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Lee SM, Balakrishnan HK, Doeven EH, Yuan D, Guijt RM. Chemical Trends in Sample Preparation for Nucleic Acid Amplification Testing (NAAT): A Review. BIOSENSORS 2023; 13:980. [PMID: 37998155 PMCID: PMC10669371 DOI: 10.3390/bios13110980] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/02/2023] [Accepted: 11/07/2023] [Indexed: 11/25/2023]
Abstract
Nucleic acid amplification testing facilitates the detection of disease through specific genomic sequences and is attractive for point-of-need testing (PONT); in particular, the early detection of microorganisms can alert early response systems to protect the public and ecosystems from widespread outbreaks of biological threats, including infectious diseases. Prior to nucleic acid amplification and detection, extensive sample preparation techniques are required to free nucleic acids and extract them from the sample matrix. Sample preparation is critical to maximize the sensitivity and reliability of testing. As the enzymatic amplification reactions can be sensitive to inhibitors from the sample, as well as from chemicals used for lysis and extraction, avoiding inhibition is a significant challenge, particularly when minimising liquid handling steps is also desirable for the translation of the assay to a portable format for PONT. The reagents used in sample preparation for nucleic acid testing, covering lysis and NA extraction (binding, washing, and elution), are reviewed with a focus on their suitability for use in PONT.
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Affiliation(s)
- Soo Min Lee
- Centre for Regional and Rural Futures (CeRRF), Deakin University, Locked Bag 20000, Geelong, VIC 3220, Australia
| | - Hari Kalathil Balakrishnan
- Department of Chemical Engineering, Khalifa University, Abu Dhabi P.O. Box 127788, United Arab Emirates;
| | - Egan H. Doeven
- School of Life and Environmental Sciences, Deakin University, Locked Bag 20000, Geelong, VIC 3220, Australia;
| | - Dan Yuan
- School of Mechanical and Mining Engineering, The University of Queensland, Brisbane, QLD 4072, Australia;
| | - Rosanne M. Guijt
- Centre for Regional and Rural Futures (CeRRF), Deakin University, Locked Bag 20000, Geelong, VIC 3220, Australia
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20
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Wax N, Pförtner LS, Holz N, Sterzl S, Melnik M, Kappel K, Bade P, Schröder U, Haase I, Fritsche J, Fischer M. Fast and User-Friendly Detection of Flatfish Species ( Pleuronectes platessa and Solea solea) via Loop-Mediated Isothermal Amplification (LAMP). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:14795-14805. [PMID: 37751470 DOI: 10.1021/acs.jafc.3c03917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
The detection of a Cytochrome b gene (cytb) for species differentiation in fish is intensively used. A fast alternative to expensive and time-consuming DNA barcoding is loop-mediated isothermal amplification (LAMP) in combination with efficient readout systems. For this reason, we developed LAMP assays for rapid species detection of Pleuronectes platessa and Solea solea, two economically important flatfish species in Europe that are prone to mislabeling. Species-specific primer sets targeting cytb were designed, and LAMP assays were optimized. With the optimized LAMP assays, we were able to detect up to 0.1 and 0.01 ng of target DNA of P. platessa and S. solea, respectively, and in each case up to 1% (w/w) of target species in mixtures with nontarget species. For future on-site detection, a lateral flow assay and a pocket-sized lab-on-phone assay were used as readout systems. The lab-on-phone assay with the S. solea specific primer set revealed cross-reactivity to Solea senegalensis. The assay targeting P. platessa proved to be highly specific. Both assays could be performed within 45 min and provided rapid and easy detection of fish species.
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Affiliation(s)
- Nils Wax
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany
| | - Laura Sophie Pförtner
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany
| | - Nathalie Holz
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany
| | - Svenja Sterzl
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany
| | - Melina Melnik
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany
| | - Kristina Kappel
- National Reference Centre for Authentic Food, Max Rubner-Institut (MRI), Hermann-Weigmann-Straße 1, 24103 Kiel, Germany
| | - Patrizia Bade
- National Reference Centre for Authentic Food, Max Rubner-Institut (MRI), Hermann-Weigmann-Straße 1, 24103 Kiel, Germany
| | - Ute Schröder
- Department of Safety and Quality of Milk and Fish Products, Max Rubner-Institut (MRI), Hermann-Weigmann-Straße 1, 24103 Kiel, Germany
| | - Ilka Haase
- National Reference Centre for Authentic Food, Max Rubner-Institut (MRI), E.-C.-Baumann-Straße 20, 95326 Kulmbach, Germany
| | - Jan Fritsche
- Department of Safety and Quality of Milk and Fish Products, Max Rubner-Institut (MRI), Hermann-Weigmann-Straße 1, 24103 Kiel, Germany
| | - Markus Fischer
- Hamburg School of Food Science, Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany
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21
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Sritong N, Ngo WW, Ejendal KFK, Linnes JC. Development of an Integrated Sample Amplification Control for Salivary Point-of-Care Pathogen Testing. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.10.03.23296477. [PMID: 37873363 PMCID: PMC10593008 DOI: 10.1101/2023.10.03.23296477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Background The COVID-19 pandemic has led to a rise in point-of-care (POC) and home-based tests, but concerns over usability, accuracy, and effectiveness have arisen. The incorporation of internal amplification controls (IACs), essential control for translational POC diagnostics, could mitigate false-negative and false-positive results due to sample matrix interference or inhibition. Although emerging POC nucleic acid amplification tests (NAATs) for detecting SARS-CoV-2 show impressive analytical sensitivity in the lab, the assessment of clinical accuracy with IACs is often overlooked. In some cases, the IACs were run spatially, complicating assay workflow. Therefore, the multiplex assay for pathogen and IAC is needed. Results We developed a one-pot duplex reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assay for saliva samples, a non-invasive and simple collected specimen for POC NAATs. The ORF1ab gene of SARS-CoV-2 was used as a target and a human 18S ribosomal RNA in human saliva was employed as an IAC to ensure clinical reliability of the RT-LAMP assay. The optimized assay could detect SARS-CoV-2 viral particles down to 100 copies/μL of saliva within 30 minutes without RNA extraction. The duplex RT-LAMP for SARS-CoV-2 and IAC is successfully amplified in the same reaction without cross-reactivity. The valid results were easily visualized in triple-line lateral flow immunoassay, in which two lines (flow control and IAC lines) represent valid negative results and three lines (flow control, IAC, and test line) represent valid positive results. This duplex assay demonstrated a clinical sensitivity of 95%, specificity of 100%, and accuracy of 96% in 30 clinical saliva samples. Significance IACs play a crucial role in ensuring user confidence with respect to the accuracy and reliability of at-home and POC molecular diagnostics. We demonstrated the multiplex capability of SARS-COV-2 and human18S ribosomal RNA RT-LAMP without complicating assay design. This generic platform can be extended in a similar manner to include human18S ribosomal RNA IACs into different clinical sample matrices.
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Affiliation(s)
- Navaporn Sritong
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Winston Wei Ngo
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Karin F. K. Ejendal
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Jacqueline C. Linnes
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
- Department of Public Health, Purdue University, West Lafayette, IN, USA
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22
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Morais-Armas S, Medina-Suárez S, Machín F. Effect of carrier yeast RNAs in the detection of SARS-CoV-2 by RT-LAMP. MICROPUBLICATION BIOLOGY 2023; 2023:10.17912/micropub.biology.000979. [PMID: 37799204 PMCID: PMC10550381 DOI: 10.17912/micropub.biology.000979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/19/2023] [Accepted: 09/19/2023] [Indexed: 10/07/2023]
Abstract
The COVID-19 pandemic caused by SARS-CoV-2 has underscored the need for rapid and accurate diagnostic methods. Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP) has emerged as a promising molecular tool in least developed countries due to its simplicity, speed, and sensitivity. Nevertheless, reliable SARS-CoV-2 detection can be challenged by the chain custody of the samples. In this context, carrier RNA can act as a preservative. In this study, we explored the potential of yeast total and transference RNA (tRNA) in the SARS-CoV-2 RT-LAMP. We have found that most optimal conditions are reached with 1 μg/μL tRNA in the RT-LAMP reaction.
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Affiliation(s)
- Samantha Morais-Armas
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Canary Islands, Spain
- Instituto de Tecnologías Biomédicas, Universidad de La Laguna, San Cristóbal de La Laguna, Canary Islands, Spain
| | - Sara Medina-Suárez
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Canary Islands, Spain
- Instituto de Tecnologías Biomédicas, Universidad de La Laguna, San Cristóbal de La Laguna, Canary Islands, Spain
| | - Félix Machín
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Canary Islands, Spain
- Instituto de Tecnologías Biomédicas, Universidad de La Laguna, San Cristóbal de La Laguna, Canary Islands, Spain
- Facultad de Ciencias de la Salud, Universidad Fernando Pessoa Canarias, Las Palmas de Gran Canaria, Canary Islands, Spain
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23
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Kim EYS, Imamura LM, Winkert Raddatz B, Timm Soares SP, Alves Ribeiro VH, Rinaldi Pavesi Nicollete D, Bergamo Santiago E, Mazega Figueredo MV, Montesanti Machado de Almeida B, Renato Rogal S. Data treatment methods for real-time colorimetric loop-mediated isothermal amplification reactions. Sci Rep 2023; 13:14397. [PMID: 37658115 PMCID: PMC10474118 DOI: 10.1038/s41598-023-40737-x] [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: 01/20/2023] [Accepted: 08/16/2023] [Indexed: 09/03/2023] Open
Abstract
With the SARS-CoV-2 pandemic and the need for affordable and rapid mass testing, colorimetric isothermal amplification reactions such as Loop-Mediated Isothermal Amplification (LAMP) are quickly rising in importance. The technique generates data that is similar to quantitative Polymerase Chain Reaction (qPCR), but instead of an endpoint color visualization, it is possible to construct a signal over a time curve. As the number of works using time-course analysis of isothermal reactions increases, there is a need to analyze data and standardize their related treatments quantitatively. Here, we take a step forward toward this goal by evaluating different available data treatments (curve models) for amplification curves, which allows for a cycle threshold-like parameter extraction. In this study, we uncover evidence of a double sigmoid equation as the most adequate model to describe amplification data from our remote diagnostics system and discuss possibilities for similar setups. We also demonstrate the use of multimodal Gompertz regression models. Thus, this work provides advances toward standardized and unbiased data reporting of Reverse Transcription (RT) LAMP reactions, which may facilitate and quicken assay interpretation, potentially enabling the application of machine learning techniques for further optimization and classification.
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Affiliation(s)
- Edson Yu Sin Kim
- Hilab, Rua José Altair Possebom, 800-CIC, Curitiba, Paraná, 81270-185, Brazil
| | | | | | | | | | | | | | | | | | - Sergio Renato Rogal
- Hilab, Rua José Altair Possebom, 800-CIC, Curitiba, Paraná, 81270-185, Brazil
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24
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Knox A, Zerna G, Beddoe T. Current and Future Advances in the Detection and Surveillance of Biosecurity-Relevant Equine Bacterial Diseases Using Loop-Mediated Isothermal Amplification (LAMP). Animals (Basel) 2023; 13:2663. [PMID: 37627456 PMCID: PMC10451754 DOI: 10.3390/ani13162663] [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: 06/28/2023] [Revised: 08/13/2023] [Accepted: 08/15/2023] [Indexed: 08/27/2023] Open
Abstract
Horses play an important role throughout the world, whether for work, culture, or leisure, providing an ever-growing significant contribution to the economy. The increase in importation and movement of horses, both nationally and internationally, has inevitably allowed for the global equine industry to grow. Subsequently, however, the potential for transmission of fatal equine bacterial diseases has also escalated, and devasting outbreaks continue to occur. To prevent such events, disease surveillance and diagnosis must be heightened throughout the industry. Current common, or "gold-standard" techniques, have shown to be inadequate at times, thus requiring newer technology to impede outbreaks. Loop-mediated isothermal amplification (LAMP) has proven to be a reliable, rapid, and accessible tool in both diagnostics and surveillance. This review will discuss equine bacterial diseases of biosecurity relevance and their current diagnostic approaches, as well as their respective LAMP assay developments. Additionally, we will provide insight regarding newer technology and advancements associated with this technique and their potential use for the outlined diseases.
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Affiliation(s)
| | | | - Travis Beddoe
- Department of Animal, Plant and Soil Sciences, Centre for AgriBioscience, La Trobe University, Bundoora, VIC 3082, Australia; (A.K.); (G.Z.)
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25
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Yan Z, Tang AA, Eshed A, Ticktin ZM, Chaudhary S, Ma D, McCutcheon G, Li Y, Wu K, Saha S, Alcantar-Fernandez J, Moreno-Camacho JL, Campos-Romero A, Collins JJ, Yin P, Green AA. Rapid and Multiplexed Nucleic Acid Detection using Programmable Aptamer-Based RNA Switches. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.06.02.23290873. [PMID: 37333364 PMCID: PMC10275000 DOI: 10.1101/2023.06.02.23290873] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Rapid, simple, and low-cost diagnostic technologies are crucial tools for combatting infectious disease. Here, we describe a class of aptamer-based RNA switches called aptaswitches that recognize specific target nucleic acid molecules and respond by initiating folding of a reporter aptamer. Aptaswitches can detect virtually any sequence and provide a fast and intense fluorescent readout, generating signals in as little as 5 minutes and enabling detection by eye with minimal equipment. We demonstrate that aptaswitches can be used to regulate folding of six different fluorescent aptamer/fluorogen pairs, providing a general means of controlling aptamer activity and an array of different reporter colors for multiplexing. By coupling isothermal amplification reactions with aptaswitches, we reach sensitivities down to 1 RNA copy/μL in one-pot reactions. Application of multiplexed one-pot reactions against RNA extracted from clinical saliva samples yields an overall accuracy of 96.67% for detection of SARS-CoV-2 in 30 minutes. Aptaswitches are thus versatile tools for nucleic acid detection that can be readily integrated into rapid diagnostic assays.
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Affiliation(s)
- Zhaoqing Yan
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
- Molecular Biology, Cell Biology & Biochemistry Program, Graduate School of Arts and Sciences, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA 02215, USA
- These authors contributed equally: Zhaoqing Yan, Anli A. Tang
| | - Anli A. Tang
- Biodesign Center for Molecular Design and Biomimetics at the Biodesign Institute, Arizona State University, Tempe, AZ, USA
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
- These authors contributed equally: Zhaoqing Yan, Anli A. Tang
| | - Amit Eshed
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA 02215, USA
| | - Zackary M. Ticktin
- Biodesign Center for Molecular Design and Biomimetics at the Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - Soma Chaudhary
- Biodesign Center for Molecular Design and Biomimetics at the Biodesign Institute, Arizona State University, Tempe, AZ, USA
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
| | - Duo Ma
- Biodesign Center for Molecular Design and Biomimetics at the Biodesign Institute, Arizona State University, Tempe, AZ, USA
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
| | - Griffin McCutcheon
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA 02215, USA
- Biodesign Center for Molecular Design and Biomimetics at the Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - Yudan Li
- Molecular Biology, Cell Biology & Biochemistry Program, Graduate School of Arts and Sciences, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA 02215, USA
| | - Kaiyue Wu
- Molecular Biology, Cell Biology & Biochemistry Program, Graduate School of Arts and Sciences, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA 02215, USA
| | - Sanchari Saha
- Biodesign Center for Molecular Design and Biomimetics at the Biodesign Institute, Arizona State University, Tempe, AZ, USA
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
| | | | | | | | - James J. Collins
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA, USA
- Institute for Medical Engineering and Science, MIT, Cambridge, MA, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Peng Yin
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Alexander A. Green
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
- Molecular Biology, Cell Biology & Biochemistry Program, Graduate School of Arts and Sciences, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA 02215, USA
- School of Molecular Sciences, Arizona State University, Tempe, AZ, USA
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26
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Lamas A, Azinheiro S, Roumani F, Prado M, Garrido-Maestu A. Evaluation of the effect of outer primer structure, and inner primer linker sequences, in the performance of Loop-mediated isothermal amplification. Talanta 2023; 260:124642. [PMID: 37167680 DOI: 10.1016/j.talanta.2023.124642] [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: 03/09/2023] [Revised: 04/27/2023] [Accepted: 05/02/2023] [Indexed: 05/13/2023]
Abstract
Loop-mediated isothermal amplification, or LAMP, is nowadays the most popular isothermal nucleic acid amplification technique. This technique implements a minimum of four primers, named outer (F3/B3) and inner primers (FIP/BIP). The inner primers hybridize in two distinct regions, and some studies have reported that the usage of a linker, typically composed of four thymines, in the middle of these primers can improve assay performance. In addition to this, dual-priming oligonucleotides, DPO, have been reported to provide highly specific reducing non-specific amplifications. Considering the large number of primers implemented in LAMP assays, in the current study the suitability of DPO primers replacing regular outer primers; and their combination with different linker sequences in the inner primers were explored. The results demonstrated that replacing standard F3/B3 by DPO primers does not significantly affect that overall performance of the assay, and provides additional stability to temperature changes. This observations were consistent regardless the type of linker implemented in the inner primers, out of which in the current study a linker composed of thymines significantly outperformed the other options tested, most likely due to a combination of sequence and physical structure.
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Affiliation(s)
- Alexandre Lamas
- Food Hygiene, Inspection and Control Laboratory, Department of Analytical Chemistry, Nutrition and Bromatology, Universidad de Santiago de Compostela, 27002, Lugo, Spain
| | - Sarah Azinheiro
- International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330, Braga, Portugal; Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Veterinary Science, University of Santiago de Compostela, 27002, Lugo, Spain
| | - Foteini Roumani
- International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330, Braga, Portugal; Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Veterinary Science, University of Santiago de Compostela, 27002, Lugo, Spain
| | - Marta Prado
- International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330, Braga, Portugal
| | - Alejandro Garrido-Maestu
- International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330, Braga, Portugal.
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27
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Alhamid G, Tombuloglu H, Al-Suhaimi E. Development of loop-mediated isothermal amplification (LAMP) assays using five primers reduces the false-positive rate in COVID-19 diagnosis. Sci Rep 2023; 13:5066. [PMID: 36977756 PMCID: PMC10044074 DOI: 10.1038/s41598-023-31760-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 03/16/2023] [Indexed: 03/30/2023] Open
Abstract
The reverse-transcription loop-mediated isothermal amplification (RT-LAMP) is a cheaper and faster testing alternative for detecting SARS-CoV-2. However, a high false-positive rate due to misamplification is one of the major limitations. To overcome misamplifications, we developed colorimetric and fluorometric RT-LAMP assays using five LAMP primers, instead of six. The gold-standard RT-PCR technique verified the assays' performance. Compared to other primer sets with six primers (N, S, and RdRp), the E-ID1 primer set, including five primers, performed superbly on both colorimetric and fluorometric assays. The sensitivity of colorimetric and fluorometric assays was 89.5% and 92.2%, respectively, with a limit of detection of 20 copies/µL. The colorimetric RT-LAMP had a specificity of 97.2% and an accuracy of 94.5%, while the fluorometric RT-LAMP obtained 99% and 96.7%, respectively. No misamplification was evident even after 120 min, which is crucial for the success of this technique. These findings are important to support the use of RT-LAMP in the healthcare systems in fighting COVID-19.
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Affiliation(s)
- Galyah Alhamid
- Master Program of Biotechnology, Institute for Research and Medical Consultations, Imam Abdulrahman Bin Faisal University, Dammam, 31441, Saudi Arabia
- Department of Genetics Research, Institute for Research and Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, Dammam, 31441, Saudi Arabia
| | - Huseyin Tombuloglu
- Department of Genetics Research, Institute for Research and Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, Dammam, 31441, Saudi Arabia.
| | - Ebtesam Al-Suhaimi
- Biology Department, College of Science and Institute of Research and Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, Dammam, 31441, Saudi Arabia
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28
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Gou H, Lin Q, Shen H, Jia K, Liang Y, Peng J, Zhang C, Qu X, Li Y, Lin J, Zhang J, Liao M. A novel linear displacement isothermal amplification with strand displacement probes (LDIA-SD) in a pocket-size device for point-of-care testing of infectious diseases. SENSORS AND ACTUATORS. B, CHEMICAL 2023; 379:133244. [PMID: 36589905 PMCID: PMC9789534 DOI: 10.1016/j.snb.2022.133244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/22/2022] [Accepted: 12/24/2022] [Indexed: 06/17/2023]
Abstract
Nucleic acid amplification is crucial for disease diagnosis, especially lethal infectious diseases such as COVID-19. Compared with PCR, isothermal amplification methods are advantageous for point-of-care testing (POCT). However, complicated primer design limits their application in detecting some short targets or sequences with abnormal GC content. Herein, we developed a novel linear displacement isothermal amplification (LDIA) method using two pairs of conventional primers and Bacillus stearothermophilus (Bst) DNA polymerase, and reactions could be accelerated by adding an extra primer. Pseudorabies virus gE (high GC content) and Salmonella fimW (low GC content) genes were used to evaluate the LDIA assay. Using strand displacement (SD) probes, a LDIA-SD method was developed to realize probe-based specific detection. Additionally, we incorporated a nucleic acid-free extraction step and a pocket-sized device to realize POCT applications of the LDIA-SD method. The LDIA-SD method has advantages including facile primer design, high sensitivity and specificity, and applicability for POCT, especially for amplification of complex sequences and detection of infectious diseases.
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Affiliation(s)
- Hongchao Gou
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
- Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Maoming, China
- Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Qijie Lin
- National and Regional Joint Engineering Laboratory for Medicament of Zoonoses Prevention and Control, Guangzhou 510642, China
- Key Laboratory of Zoonoses, Ministry of Agriculture, Guangzhou 510642, China
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Haiyan Shen
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
- Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Maoming, China
- Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Kaiyuan Jia
- National and Regional Joint Engineering Laboratory for Medicament of Zoonoses Prevention and Control, Guangzhou 510642, China
- Key Laboratory of Zoonoses, Ministry of Agriculture, Guangzhou 510642, China
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Yucen Liang
- National and Regional Joint Engineering Laboratory for Medicament of Zoonoses Prevention and Control, Guangzhou 510642, China
- Key Laboratory of Zoonoses, Ministry of Agriculture, Guangzhou 510642, China
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Junhao Peng
- National and Regional Joint Engineering Laboratory for Medicament of Zoonoses Prevention and Control, Guangzhou 510642, China
- Key Laboratory of Zoonoses, Ministry of Agriculture, Guangzhou 510642, China
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Chunhong Zhang
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
- Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Maoming, China
- Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
| | - Xiaoyun Qu
- National and Regional Joint Engineering Laboratory for Medicament of Zoonoses Prevention and Control, Guangzhou 510642, China
- Key Laboratory of Zoonoses, Ministry of Agriculture, Guangzhou 510642, China
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Yanbin Li
- Department of Biological and Agricultural Engineering, University of Arkansas, Fayetteville, AR 72701, USA
| | - Jianhan Lin
- Key Laboratory of Agricultural Information Acquisition Technology, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing 100083, China
| | - Jianmin Zhang
- National and Regional Joint Engineering Laboratory for Medicament of Zoonoses Prevention and Control, Guangzhou 510642, China
- Key Laboratory of Zoonoses, Ministry of Agriculture, Guangzhou 510642, China
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Ming Liao
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonoses Prevention and Control, Guangzhou 510642, China
- Guangdong Provincial Key Laboratory of Livestock Disease Prevention, Guangzhou, China
- Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Maoming, China
- Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Guangzhou, China
- Key Laboratory of Zoonoses, Ministry of Agriculture, Guangzhou 510642, China
- Key Laboratory of Zoonoses Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Key Laboratory of Animal Vaccine Development, Ministry of Agriculture, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
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29
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Szobi A, Buranovská K, Vojtaššáková N, Lovíšek D, Özbaşak HÖ, Szeibeczederová S, Kapustian L, Hudáčová Z, Kováčová V, Drobná D, Putaj P, Bírová S, Čirková I, Čarnecký M, Kilián P, Jurkáček P, Čabanová V, Boršová K, Sláviková M, Vaňová V, Klempa B, Čekan P, Paul ED. Vivid COVID-19 LAMP is an ultrasensitive, quadruplexed test using LNA-modified primers and a zinc ion and 5-Br-PAPS colorimetric detection system. Commun Biol 2023; 6:233. [PMID: 36864129 PMCID: PMC9979146 DOI: 10.1038/s42003-023-04612-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 02/20/2023] [Indexed: 03/04/2023] Open
Abstract
Sensitive and rapid point-of-care assays have been crucial in the global response to SARS-CoV-2. Loop-mediated isothermal amplification (LAMP) has emerged as an important diagnostic tool given its simplicity and minimal equipment requirements, although limitations exist regarding sensitivity and the methods used to detect reaction products. We describe the development of Vivid COVID-19 LAMP, which leverages a metallochromic detection system utilizing zinc ions and a zinc sensor, 5-Br-PAPS, to circumvent the limitations of classic detection systems dependent on pH indicators or magnesium chelators. We make important strides in improving RT-LAMP sensitivity by establishing principles for using LNA-modified LAMP primers, multiplexing, and conducting extensive optimizations of reaction parameters. To enable point-of-care testing, we introduce a rapid sample inactivation procedure without RNA extraction that is compatible with self-collected, non-invasive gargle samples. Our quadruplexed assay (targeting E, N, ORF1a, and RdRP) reliably detects 1 RNA copy/µl of sample (=8 copies/reaction) from extracted RNA and 2 RNA copies/µl of sample (=16 copies/reaction) directly from gargle samples, making it one of the most sensitive RT-LAMP tests and even comparable to RT-qPCR. Additionally, we demonstrate a self-contained, mobile version of our assay in a variety of high-throughput field testing scenarios on nearly 9,000 crude gargle samples. Vivid COVID-19 LAMP can be an important asset for the endemic phase of COVID-19 as well as preparing for future pandemics.
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Affiliation(s)
- Adrián Szobi
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Katarína Buranovská
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Nina Vojtaššáková
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Daniel Lovíšek
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Halil Önder Özbaşak
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Sandra Szeibeczederová
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Liudmyla Kapustian
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Zuzana Hudáčová
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
- Stanford University, 730 Escondido Rd., Stanford, CA, 94305, USA
| | - Viera Kováčová
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
- University of Cologne, Institute for Biological Physics, Zülpicher Str. 77, 50937, Köln, Germany
| | - Diana Drobná
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Piotr Putaj
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Stanislava Bírová
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Ivana Čirková
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Martin Čarnecký
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Peter Kilián
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA
| | - Peter Jurkáček
- AstonITM s.r.o., Račianska 153, 831 54, Bratislava, Slovakia
| | - Viktória Čabanová
- Biomedical Research Center, Slovak Academy of Sciences, Institute of Virology, Dúbravská cesta 9, 845 05, Bratislava, Slovakia
| | - Kristína Boršová
- Biomedical Research Center, Slovak Academy of Sciences, Institute of Virology, Dúbravská cesta 9, 845 05, Bratislava, Slovakia
| | - Monika Sláviková
- Biomedical Research Center, Slovak Academy of Sciences, Institute of Virology, Dúbravská cesta 9, 845 05, Bratislava, Slovakia
| | - Veronika Vaňová
- Biomedical Research Center, Slovak Academy of Sciences, Institute of Virology, Dúbravská cesta 9, 845 05, Bratislava, Slovakia
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, Ilkovičova 6, 842 15, Bratislava, Slovakia
| | - Boris Klempa
- Biomedical Research Center, Slovak Academy of Sciences, Institute of Virology, Dúbravská cesta 9, 845 05, Bratislava, Slovakia
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University, Ilkovičova 6, 842 15, Bratislava, Slovakia
| | - Pavol Čekan
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia.
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA.
| | - Evan D Paul
- MultiplexDX, s.r.o., Comenius University Science Park, Ilkovičova 8, 841 04, Bratislava, Slovakia.
- MultiplexDX, Inc., One Research Court, Suite 450, Rockville, MD, 20850, USA.
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Tarim EA, Oksuz C, Karakuzu B, Appak O, Sayiner AA, Tekin HC. Electromechanical RT-LAMP device for portable SARS-CoV-2 detection. Talanta 2023; 254:124190. [PMID: 36521325 PMCID: PMC9733968 DOI: 10.1016/j.talanta.2022.124190] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 12/06/2022] [Accepted: 12/08/2022] [Indexed: 12/14/2022]
Abstract
Rapid point-of-care tests for infectious diseases are essential, especially in pandemic conditions. We have developed a point-of-care electromechanical device to detect SARS-CoV-2 viral RNA using the reverse-transcription loop-mediated isothermal amplification (RT-LAMP) principle. The developed device can detect SARS-CoV-2 viral RNA down to 103 copies/mL and from a low amount of sample volumes (2 μL) in less than an hour of standalone operation without the need for professional labor and equipment. Integrated Peltier elements in the device keep the sample at a constant temperature, and an integrated camera allows automated monitoring of LAMP reaction in a stirring sample by using colorimetric analysis of unfocused sample images in the hue/saturation/value color space. This palm-fitting, portable and low-cost device does not require a fully focused sample image for analysis, and the operation could be stopped automatically through image analysis when the positive test results are obtained. Hence, viral infections can be detected with the portable device produced without the need for long, expensive, and labor-intensive tests and equipment, which can make the viral tests disseminated at the point-of-care.
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Affiliation(s)
- E. Alperay Tarim
- Department of Bioengineering, Izmir Institute of Technology, Izmir 35430, Turkey
| | - Cemre Oksuz
- Department of Bioengineering, Izmir Institute of Technology, Izmir 35430, Turkey
| | - Betul Karakuzu
- Department of Bioengineering, Izmir Institute of Technology, Izmir 35430, Turkey
| | - Ozgur Appak
- Department of Medical Microbiology, Dokuz Eylul University, Faculty of Medicine, Izmir 35330, Turkey
| | - Ayca Arzu Sayiner
- Department of Medical Microbiology, Dokuz Eylul University, Faculty of Medicine, Izmir 35330, Turkey
| | - H. Cumhur Tekin
- Department of Bioengineering, Izmir Institute of Technology, Izmir 35430, Turkey,METU MEMS Center, Ankara 06520, Turkey,Corresponding author. Department of Bioengineering, Izmir Institute of Technology, Izmir 35430, Turkey
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Yu Z, Xu J, She Q. Harnessing the LdCsm RNA Detection Platform for Efficient microRNA Detection. Int J Mol Sci 2023; 24:ijms24032857. [PMID: 36769177 PMCID: PMC9918065 DOI: 10.3390/ijms24032857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/24/2023] [Accepted: 01/27/2023] [Indexed: 02/05/2023] Open
Abstract
In cancer diagnosis, diverse microRNAs (miRNAs) are used as biomarkers for carcinogenesis of distinctive human cancers. Thus, the detection of these miRNAs and their quantification are very important in prevention of cancer diseases in human beings. However, efficient RNA detection often requires RT-PCR, which is very complex for miRNAs. Recently, the development of CRISPR-based nucleic acid detection tools has brought new promises to efficient miRNA detection. Three CRISPR systems can be explored for miRNA detection, including type III, V, and VI, among which type III (CRISPR-Cas10) systems have a unique property as they recognize RNA directly and cleave DNA collaterally. In particular, a unique type III-A Csm system encoded by Lactobacillus delbrueckii subsp. bulgaricus (LdCsm) exhibits robust target RNA-activated DNase activity, which makes it a promising candidate for developing efficient miRNA diagnostic tools. Herein, LdCsm was tested for RNA detection using fluorescence-quenched DNA reporters. We found that the system is capable of specific detection of miR-155, a microRNA implicated in the carcinogenesis of human breast cancer. The RNA detection system was then improved by various approaches including assay conditions and modification of the 5'-repeat tag of LdCsm crRNAs. Due to its robustness, the resulting LdCsm detection platform has the potential to be further developed as a better point-of-care miRNA diagnostics relative to other CRISPR-based RNA detection tools.
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Affiliation(s)
| | | | - Qunxin She
- Correspondence: ; Tel.: +86-532-58631522
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Hoffmann AT, da Silva MS, Gularte JS, Pasqualotto AC, Proença Módena JL, Hansen AW, Stadñik CMB, Sukienik TCT, Demoliner M, Heldt FH, Filippi M, Pereira VMDAG, de Marques CG, Kohler II, Quevedo DMD, Spilki FR. Dynamics of nosocomial SARS-CoV-2 transmissions: Facing the challenge of variants of concern in a Brazilian reference hospital. J Med Virol 2023; 95:e28446. [PMID: 36579775 PMCID: PMC9880750 DOI: 10.1002/jmv.28446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 12/12/2022] [Accepted: 12/18/2022] [Indexed: 12/30/2022]
Abstract
The hospital environment can be considered a high risk for the occurrence of SARS-CoV-2 transmission outbreaks, either for health professionals who are directly involved in the care of suspected or confirmed cases of the disease, or for patients, for being in an environment more vulnerable to the acquisition of nosocomial infections. In this molecular epidemiology study, we aimed to analyze the occurrence and transmission dynamics of SARS-CoV-2 in outbreaks and local chains of transmission in a large tertiary teaching hospital in southern Brazil, in addition to verifying circulating strains and their epidemiological relation in the local context, from September 21, 2020 to October 5, 2021. Positive samples involved in COVID-19 clusters or outbreaks were analyzed using clinical, epidemiological and genomic data. Different lineages and sublineages among patients in the same room were observed. Most patients had their first clinical manifestation, evidence of suspicion, and diagnostic confirmation within 7-14 days or >14 days after hospital admission. The patients who have contact with confirmed cases of COVID-19 spent, on average, 6.28 days in the same environment until the positive test. There was a significant association between the outcome and the number of vaccine doses (p < 0.05), where those who received two doses presented a lower occurrence of death. There was a total replacement of variant of concern (VOC) Gamma by VOC Delta from August 2021 at the study site. Although the epidemiological analysis indicates nosocomial infections, through genomic sequencing, it was established that most of the hospital outbreaks had different origins. These findings highlight the utility of integrating epidemiological and genomic data to identify possible routes of viral entry and dissemination.
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Affiliation(s)
- Andressa Taíz Hoffmann
- Controle de Infecção HospitalarSanta Casa de Misericórdia de Porto AlegrePorto AlegreRio Grande do SulBrazil
| | - Mariana Soares da Silva
- Laboratório de Microbiologia MolecularUniversidade FeevaleNovo HamburgoRio Grande do SulBrazil
| | - Juliana Schons Gularte
- Laboratório de Microbiologia MolecularUniversidade FeevaleNovo HamburgoRio Grande do SulBrazil
| | | | | | - Alana Witt Hansen
- Laboratório de Microbiologia MolecularUniversidade FeevaleNovo HamburgoRio Grande do SulBrazil
| | | | | | - Meriane Demoliner
- Laboratório de Microbiologia MolecularUniversidade FeevaleNovo HamburgoRio Grande do SulBrazil
| | - Fágner Henrique Heldt
- Laboratório de Microbiologia MolecularUniversidade FeevaleNovo HamburgoRio Grande do SulBrazil
| | - Micheli Filippi
- Laboratório de Microbiologia MolecularUniversidade FeevaleNovo HamburgoRio Grande do SulBrazil
| | | | | | - Ionara Ines Kohler
- Laboratório de Análises ClínicasSanta Casa de Misericórdia de Porto AlegrePorto AlegreBrazil
| | | | - Fernando Rosado Spilki
- Laboratório de Microbiologia MolecularUniversidade FeevaleNovo HamburgoRio Grande do SulBrazil
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Development and Validation of Rapid Colorimetric Reverse Transcription Loop-Mediated Isothermal Amplification for Detection of Rift Valley Fever Virus. Adv Virol 2023; 2023:1863980. [PMID: 36755743 PMCID: PMC9902148 DOI: 10.1155/2023/1863980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 12/22/2022] [Accepted: 01/20/2023] [Indexed: 01/31/2023] Open
Abstract
Rift Valley fever virus (RVFV) is a high-priority zoonotic pathogen with the ability to cause massive loss during its outbreak within a very short period of time. Lack of a highly sensitive, instant reading diagnostic method for RVFV, which is more suitable for on-site testing, is a big gap that needs to be addressed. The aim of this study was to develop a novel one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP) method for the rapid detection of RVFV. To achieve this, the selected RVFV M segment nucleotide sequences were aligned using Multiple Sequence Comparison by Log-Expectation (MUSCLE) software in MEGA11 version 11.0.11 program to identify conserved regions. A 211 pb sequence was identified and six different primers to amplify it were designed using NEB LAMP Primer design tool version 1.1.0. The specificity of the designed primers was tested using primer BLAST, and a primer set, specific to RVFV and able to form a loop, was selected. In this study, we developed a single-tube test based on calorimetric RT-LAMP that enabled the visual detection of RVFV within 30 minutes at 65°C. Diagnostic sensitivity and specificity of the newly developed kit were compared with RVFV qRT-PCR, using total RNA samples extracted from 118 blood samples. The colorimetric RT-LAMP assay had a sensitivity of 98.36% and a specificity of 96.49%. The developed RT-LAMP was found to be tenfold more sensitive compared to the RVFV qRT-PCR assay commonly used in the confirmatory diagnosis of RVFV.
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Figueiredo D, Cascalheira A, Goncalves J. Rapid, multiplex detection of SARS-CoV-2 using isothermal amplification coupled with CRISPR-Cas12a. Sci Rep 2023; 13:849. [PMID: 36646742 PMCID: PMC9842216 DOI: 10.1038/s41598-022-27133-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 12/26/2022] [Indexed: 01/18/2023] Open
Abstract
In December 2019 an outbreak erupted due to the beta coronavirus Severe Acute Respiratory Syndrome Coronavirus 2 in Wuhan, China. The disease caused by this virus (COVID-19) rapidly spread to all parts of the globe leading to a global pandemic. Efforts to combat the pandemic rely on RT-qPCR diagnostic tests that have high turnaround times (~ 24 h), are easily contaminated, need specialized equipment, facilities, and personnel that end up increasing the overall costs of this method. Loop-mediated isothermal amplification (LAMP) coupled with a reverse transcription step (RT-LAMP) is an alternative diagnostic method that can easily overcome these obstacles, when coupled with CRISPR/Cas it can eliminate false positives. Here we report a fast (~ 40 min), highly sensitive, point-of-care multiplex RT-LAMP and CRISPR/Cas12a assay to detect SARS-CoV-2. This fluorescence-based test achieved 100% specificity and 93% sensitivity using 25 positives and 50 negative patient samples for Ct < 35. Our reported LoD of 3 copies/µL will enable the robust, fast detection of the virus in a dedicated equipment which is a major step towards population-wide accessible testing.
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Affiliation(s)
| | | | - Joao Goncalves
- iMed- Research Institute for Medicines, Faculdade Farmácia da Universidade Lisboa, Lisboa, Portugal.
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A Comparative Study on Visual Detection of Mycobacterium tuberculosis by Closed Tube Loop-Mediated Isothermal Amplification: Shedding Light on the Use of Eriochrome Black T. Diagnostics (Basel) 2023; 13:diagnostics13010155. [PMID: 36611447 PMCID: PMC9818645 DOI: 10.3390/diagnostics13010155] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/29/2022] [Accepted: 12/29/2022] [Indexed: 01/04/2023] Open
Abstract
Loop-mediated isothermal amplification is a promising candidate for the rapid detection of Mycobacterium tuberculosis. However, the high potential for carry-over contamination is the main obstacle to its routine use. Here, a closed tube LAMP was intended for the visual detection of Mtb to compare turbidimetric and two more favorable colorimetric methods using calcein and hydroxy naphthol blue (HNB). Additionally, a less studied dye (i.e., eriochrome black T (EBT)) was optimized in detail in the reaction for the first time. Mtb purified DNA and 30 clinical specimens were used to respectively determine the analytical and diagnostic sensitivities of each method. The turbidimetric method resulted in the best analytical sensitivity (100 fg DNA/reaction), diagnostic sensitivity and specificity (100%), and time-to-positivity of the test (15 min). However, this method is highly prone to subjective error in reading the results. Moreover, HNB-, calcein-, and EBT-LAMP could respectively detect 100 fg, 1 pg, and 1 pg DNA/reaction (the analytical sensitivities) in 30, 15, and 30 min, while the diagnostic sensitivity and specificity were respectively 93.3% and 100% for them all. Interestingly, EBT-LAMP showed the lowest potential for subjective error in reading the results. This report helps judiciously choose the most appropriate visual method, taking a step forward toward the field applicability of LAMP for the detection of Mtb, particularly in resource-limited settings.
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Dannenmann M, Klenner F, Bönigk J, Pavlista M, Napoleoni M, Hillier J, Khawaja N, Olsson-Francis K, Cable ML, Malaska MJ, Abel B, Postberg F. Toward Detecting Biosignatures of DNA, Lipids, and Metabolic Intermediates from Bacteria in Ice Grains Emitted by Enceladus and Europa. ASTROBIOLOGY 2023; 23:60-75. [PMID: 36454287 DOI: 10.1089/ast.2022.0063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The reliable identification of biosignatures is key to the search for life elsewhere. On ocean worlds like Enceladus or Europa, this can be achieved by impact ionization mass spectrometers, such as the SUrface Dust Analyzer (SUDA) on board NASA's upcoming Europa Clipper mission. During spacecraft flybys, these instruments can sample ice grains formed from subsurface water and emitted by these moons. Previous laboratory analog experiments have demonstrated that SUDA-type instruments could identify amino acids, fatty acids, and peptides in ice grains and discriminate between their abiotic and biotic origins. Here, we report experiments simulating impact ionization mass spectra of ice grains containing DNA, lipids, and metabolic intermediates extracted from two bacterial cultures: Escherichia coli and Sphingopyxis alaskensis. Salty Enceladan or Europan ocean waters were simulated using matrices with different NaCl concentrations. Characteristic mass spectral signals, such as DNA nucleobases, are clearly identifiable at part-per-million-level concentrations. Mass spectra of all substances exhibit unambiguous biogenic patterns, which in some cases show significant differences between the two bacterial species. Sensitivity to the biosignatures decreases with increasing matrix salinity. The experimental parameters indicate that future impact ionization mass spectrometers will be most sensitive to the investigated biosignatures for ice grain encounter speeds of 4-6 km/s.
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Affiliation(s)
- Marie Dannenmann
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Fabian Klenner
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Janine Bönigk
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Miriam Pavlista
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Maryse Napoleoni
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Jon Hillier
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Nozair Khawaja
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Karen Olsson-Francis
- AstrobiologyOU, Faculty of Science, Technology, Engineering & Mathematics, The Open University, Milton Keynes, United Kingdom
| | - Morgan L Cable
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Michael J Malaska
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Bernd Abel
- Leibniz-Institute of Surface Engineering (IOM), Leipzig, Germany
- Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, Leipzig University, Leipzig, Germany
| | - Frank Postberg
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
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Abstract
INTRODUCTION The SARS-CoV-2 pandemic, and the subsequent limitations on standard diagnostics, has vastly expanded the user base of Reverse Transcription Loop-mediated isothermal Amplification (RT-LAMP) in fundamental research and development. RT-LAMP has also penetrated commercial markets, with emergency use authorizations for clinical diagnosis. AREAS COVERED This review discusses the role of RT-LAMP within the context of other technologies like RT-qPCR and rapid antigen tests, progress in sample preparation strategies to enable simplified workflow for RT-LAMP directly from clinical specimens, new challenges with primer and assay design for the evolving pandemic, prominent detection modalities including colorimetric and CRISPR-mediated methods, and translational research and commercial development of RT-LAMP for clinical applications. EXPERT OPINION RT-LAMP occupies a middle ground between RT-qPCR and rapid antigen tests. The simplicity approaches that of rapid antigen tests, making it suitable for point-of-care use, but the sensitivity nears that of RT-qPCR. RT-LAMP still lags RT-qPCR in fundamental understanding of the mechanism, and the interplay between sample preparation and assay performance. Industry is now beginning to address issues around scalability and usability, which could finally enable LAMP and RT-LAMP to find future widespread application as a diagnostic for other conditions, including other pathogens with pandemic potential.
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Affiliation(s)
- Gihoon Choi
- Biotechnology & Bioengineering Department, Sandia National Laboratories, Livermore, CA, USA
| | - Taylor J Moehling
- Biotechnology & Bioengineering Department, Sandia National Laboratories, Livermore, CA, USA
| | - Robert J Meagher
- Biotechnology & Bioengineering Department, Sandia National Laboratories, Livermore, CA, USA
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Biswas P, Mukunthan Sulochana GN, Banuprasad TN, Goyal P, Modak D, Ghosh AK, Chakraborty S. All-Serotype Dengue Virus Detection through Multilayered Origami-Based Paper/Polymer Microfluidics. ACS Sens 2022; 7:3720-3729. [PMID: 36383745 DOI: 10.1021/acssensors.2c01525] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The dengue virus (DENV) infection commonly triggers threatening seasonal outbreaks all around the globe (estimated yearly infections are in the order of 100 million, combining all the viral serotypes), testifying the need for early detection to facilitate disease management and patient recovery. The laboratory-based testing procedures for detecting DENV infection early enough are challenged by the need of resourced settings that result in inevitable cost penalty and unwarranted delay in obtaining the test results due to distance-related factors with respect to the patient's location. Recognizing that the introduction of alternative extreme point-of-care technologies for early detection may potentially mitigate this challenge largely, we develop here a multiplex paper/polymer-based detection strip that interfaces with an all-in-one simple portable device, synchronizing the pipeline of nucleic acid isolation, isothermal amplification, and colorimetric analytics as well as readout for detecting all the four serotypes of dengue viruses in around 30 min from about 50 μL of human blood serum with high specificity and sensitivity. Aligned with the mandatory guidelines of the World Health Organization, the ultralow-cost test is ideal for dissemination at different community centers via a user-friendly device interface, not only as a critical surveillance measure in recognizing the potential cocirculation of the infection across regions that are hyperendemic for all four DENV serotypes but also for facilitating effective monitoring of patients infected by any one of the particular viral serotypes as well as timely administration of life-saving measures on need.
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Affiliation(s)
- Poulomi Biswas
- School of Medical Science and Technology, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | | | | | - Pankaj Goyal
- School of Nanoscience and Technology, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | | | - Ananta Kumar Ghosh
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Suman Chakraborty
- Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
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Shirshikov FV, Bespyatykh JA. Loop-Mediated Isothermal Amplification: From Theory to Practice. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2022; 48:1159-1174. [PMID: 36590469 PMCID: PMC9788664 DOI: 10.1134/s106816202206022x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/01/2022] [Accepted: 06/17/2022] [Indexed: 12/24/2022]
Abstract
Increasing the accuracy of pathogen identification and reducing the duration of analysis remain relevant for modern molecular diagnostics up to this day. In laboratory and clinical practice, detection of pathogens mostly relies on methods of nucleic acid amplification, among which the polymerase chain reaction (PCR) is considered the "gold standard." Nevertheless, in some cases, isothermal amplification methods act as an alternative to PCR diagnostics. Upon more than thirty years of the development of isothermal DNA synthesis, the appearance of loop-mediated isothermal amplification (LAMP) has enabled new directions of in-field diagnostics of bacterial and viral infections. This review examines the key characteristics of the LAMP method and corresponding features in practice. We discuss the structure of LAMP amplicons with single-stranded loops, which have the sites for primer annealing under isothermal conditions. The latest achievements in the modification of the LAMP method are analyzed, which allow considering it as a unique platform for creating the next-generation diagnostic assays.
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Affiliation(s)
- F. V. Shirshikov
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia
| | - J. A. Bespyatykh
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia
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Development of an optimized colorimetric RT-LAMP for SARS-CoV-2 assay with enhanced procedure controls for remote diagnostics. Sci Rep 2022; 12:21424. [PMID: 36503901 PMCID: PMC9741705 DOI: 10.1038/s41598-022-25872-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 12/06/2022] [Indexed: 12/14/2022] Open
Abstract
The coronavirus pandemic accentuated the need for molecular diagnostic tests. A technique highly used to this end is the Polymerase Chain Reaction (PCR)-a sensitive and specific technique commonly used as the gold standard for molecular diagnostics. However, it demands highly trained personnel and high-maintenance equipment and is relatively time-consuming. An alternative is the Loop-Mediated Isothermal Amplification (LAMP) technique, which doesn't need sample purification or expensive equipment, and is similar to PCR when compared in sensitivity and specificity. In this paper, we developed an optimized colorimetric Reverse Transcriptase Loop-Mediated Isothermal Amplification (RT-LAMP) Point-of-Care test using a portable device to diagnose COVID-19. Variables such as concentration of primers, magnesium sulfate, betaine, hydrochloride guanidine, Bst, and temperature of the reactions were tested. We also created a pipetting quality control system-using a combination of dyes-to avoid false negatives due to a lack of samples added to the reaction test tube. Mineral oil was incorporated in the composition of the RT-LAMP reactions to avoid evaporation when a heating lid isn't available. The final RT-LAMP test is tenfold more sensitive when compared to the WarmStart Colorimetric Master mix from New England Biolabs with a sensitivity of 5 copies per μL.
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Zhigaleva ON, Ermolaev II, Mardanly SG, Gashenko TY. Analysis of the domestic market for COVID-19 diagnostic kits by real-time reverse-transcription polymerase chain reaction. Klin Lab Diagn 2022; 67:672-677. [PMID: 36398778 DOI: 10.51620/0869-2084-2022-67-11-672-677] [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] [Indexed: 06/16/2023]
Abstract
COVID-19 is a disease caused by the new coronavirus SARS-CoV-2. Outbreaks were first reported in China on December 31, 2019. Exactly one month later, the WHO declared the outbreak a public health emergency of international concern, and on March 11, it was declared a pandemic. In February, the infection began to spread rapidly to various countries, with Europe declared the center. By April 17, 2020, cases had been confirmed in all subjects of the Russian Federation. At the beginning of September 2020, the number of cases exceeded one million; at November 19, two million; at December 26, three million. At February 10, 2021, four million; at May 23, five million; at July 20, six million; at September 5, seven million; at October 18, eight million; at November 13, nine million; and at December 12, 2021, ten million. The rapid spread of the virus, accompanied by a significant increase in the number of infections and deaths. A total of about 18.6 million cases were recorded at the end of the first half of 2022. The total number of deaths from coronavirus in Russia at that time was 382,313 (2.06% of all cases). The number of tests performed by various analytical methods amounted to over 274, 5 million, i.e. 1.9 million per 1 million population. The rapid spread and the increase in new infections caused by SARS-CoV-2 made it necessary to use new epidemiological and diagnostic approaches based on fast, accurate and reliable technology for detecting the infectious agent. One such virus detection method is polymerase chain reaction with reverse transcription and real-time detection of the results. The review presents the domestic market offerings of PCR diagnostic kits and provides their comparative consumer characteristics.
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Affiliation(s)
| | - I I Ermolaev
- JSC «EKOlab»
- State educational institution of higher education of the Moscow region «State Humanitarian University of Technology» (GGTU)
| | - S G Mardanly
- JSC «EKOlab»
- State educational institution of higher education of the Moscow region «State Humanitarian University of Technology» (GGTU)
| | - T Yu Gashenko
- JSC «EKOlab»
- State educational institution of higher education of the Moscow region «State Humanitarian University of Technology» (GGTU)
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Efficient multiplexing and variant discrimination in reverse-transcription loop-mediated isothermal amplification with sequence-specific hybridization probes. Biotechniques 2022; 73:247-255. [DOI: 10.2144/btn-2022-0096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Loop-mediated isothermal amplification (LAMP) has proven a robust and reliable nucleic acid amplification method that is well suited for simplified and rapid molecular diagnostics. Various approaches have emerged for sequence-specific detection of LAMP products, but with limitations to their widespread utility or applicability for single-nucleotide polymorphism detection and multiplexing. Here we demonstrate the use of simple hybridization probes (as used for qPCR) that enable simple multiplexing and SARS-CoV-2 variant typing in reverse-transcription LAMP. This approach requires no modification to the LAMP primers and is amenable to the detection of single-nucleotide polymorphisms and small sequence changes, which is usually difficult in LAMP. By extending LAMP’s ability to be utilized for multitarget and single-base change detection, we hope to increase its potential to enable more and better molecular diagnostic testing.
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43
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Doria G, Clemente C, Coelho E, Colaço J, Crespo R, Semikhodskii A, Mansinho H, Dinis M, Carvalho MF, Casmarrinha M, Samina C, Vidal AC, Delarue F, Graúdo S, Santos AC, Peças D, Carreira O, Marques R, Gaspar C, Flores O. An isothermal lab-on-phone test for easy molecular diagnosis of SARS-CoV-2 near patients and in less than 1 hour. Int J Infect Dis 2022; 123:1-8. [PMID: 35878801 PMCID: PMC9307284 DOI: 10.1016/j.ijid.2022.07.042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 06/29/2022] [Accepted: 07/15/2022] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVES The performance of a new point-of-care CE-IVD-marked isothermal lab-on-phone COVID-19 assay was assessed in comparison to a gold standard real-time reverse transcriptase-PCR method. METHODS The study was conducted following a nonprobability sampling of ≥16-year-old volunteers from three different laboratories, using direct mouthwash (N = 24) or nasopharyngeal (N = 191) clinical samples. RESULTS The assay demonstrated 95.19% sensitivity and 100% specificity for detection of SARS-CoV-2 in direct nasopharyngeal crude samples and 78.95% sensitivity and 100% specificity in direct mouthwash crude samples. It also successfully detected currently predominant SARS-CoV-2 variants of concern (Beta B.1.351, Delta B.1.617.2, and Omicron B.1.1.529) and demonstrated to be inert against potential cross-reactions of other common respiratory pathogens that cause infections that present similar symptoms to COVID-19. CONCLUSION This lab-on-phone pocket-sized assay relies on an isothermal amplification of SARS-CoV-2's N and E genes, taking just 50 minutes from sample to result, with only 2 minutes of hands-on time. It presents good performance when using direct nasopharyngeal crude samples, enabling a low-cost, real-time, rapid, and accurate identification of SARS-CoV-2 infections at the point of care, which is important for both clinical management and population screening, as a tool to break the chain of transmission of COVID-19 pandemic, especially in low-resources environments.
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Affiliation(s)
- Gonçalo Doria
- STAB VIDA Lda, Rua dos Inventores, Caparica, Portugal,Correspondence to: Att. Gonçalo Doria, STAB VIDA Lda, Madan Parque - Rua dos Inventores, Sala 2.18, 2825-182 Caparica, Portugal
| | | | | | - João Colaço
- STAB VIDA Lda, Rua dos Inventores, Caparica, Portugal
| | - Rui Crespo
- STAB VIDA Lda, Rua dos Inventores, Caparica, Portugal
| | - Andrei Semikhodskii
- Medical Genomics Ltd, London, United Kingdom,King Saud Bin Abdulaziz's University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
| | | | - Magno Dinis
- Oncology Service, Garcia de Orta Hospital, Almada, Portugal
| | | | | | - Cátia Samina
- Oncology Service, Garcia de Orta Hospital, Almada, Portugal
| | - Ana Cristina Vidal
- Garcia de Orta Center, Garcia de Orta Hospital, Almada, Portugal,Escola Superior de Saúde Egas Moniz, Caparica, Portugal
| | - Francisca Delarue
- Internal Medicine Service - Garcia de Orta Center, Garcia de Orta Hospital, Almada, Portugal
| | - Susana Graúdo
- Internal Medicine Service - Garcia de Orta Center, Garcia de Orta Hospital, Almada, Portugal
| | - Ana Catarina Santos
- Internal Medicine Service - Garcia de Orta Center, Garcia de Orta Hospital, Almada, Portugal
| | - David Peças
- Internal Medicine Service - Garcia de Orta Center, Garcia de Orta Hospital, Almada, Portugal
| | - Olga Carreira
- Clinical Pathology Service, Garcia de Orta Hospital, Almada, Portugal
| | - Raquel Marques
- Clinical Pathology Service, Garcia de Orta Hospital, Almada, Portugal
| | - Carina Gaspar
- Clinical Pathology Service, Garcia de Orta Hospital, Almada, Portugal
| | - Orfeu Flores
- STAB VIDA Lda, Rua dos Inventores, Caparica, Portugal
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44
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Improved visual detection of DNA amplification using pyridylazophenol metal sensing dyes. Commun Biol 2022; 5:999. [PMID: 36130997 PMCID: PMC9491268 DOI: 10.1038/s42003-022-03973-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 09/09/2022] [Indexed: 11/09/2022] Open
Abstract
Detection of nucleic acid amplification has typically required sophisticated laboratory instrumentation, but as the amplification techniques have moved away from the lab, complementary detection techniques have been implemented to facilitate point-of-care, field, and even at-home applications. Simple visual detection approaches have been widely used for isothermal amplification methods, but have generally displayed weak color changes or been highly sensitive to sample and atmospheric effects. Here we describe the use of pyridylazophenol dyes and binding to manganese ion to produce a strong visible color that changes in response to nucleic acid amplification. This detection approach is easily quantitated with absorbance, rapidly and clearly visible by eye, robust to sample effects, and notably compatible with both isothermal and PCR amplification. Nucleic acid amplification and molecular diagnostic methods are being used in an increasing number of novel applications and settings, and the ability to reliably and sensitively detect them without the need for additional instrumentation will enable even more access to these powerful techniques.
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45
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Zasada AA, Mosiej E, Prygiel M, Polak M, Wdowiak K, Formińska K, Ziółkowski R, Żukowski K, Marchlewicz K, Nowiński A, Nowińska J, Rastawicki W, Malinowska E. Detection of SARS-CoV-2 Using Reverse Transcription Helicase Dependent Amplification and Reverse Transcription Loop-Mediated Amplification Combined with Lateral Flow Assay. Biomedicines 2022; 10:biomedicines10092329. [PMID: 36140431 PMCID: PMC9496027 DOI: 10.3390/biomedicines10092329] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/13/2022] [Accepted: 09/17/2022] [Indexed: 11/20/2022] Open
Abstract
Rapid and accurate detection and identification of pathogens in clinical samples is essential for all infection diseases. However, in the case of epidemics, it plays a key role not only in the implementation of effective therapy but also in limiting the spread of the epidemic. In this study, we present the application of two nucleic acid isothermal amplification methods—reverse transcription helicase dependent amplification (RT-HDA) and reverse transcription loop-mediated amplification (RT-LAMP)—combined with lateral flow assay as the tools for the rapid detection of SARS-CoV-2, the etiological agent of COVID-19, which caused the ongoing global pandemic. In order to optimize the RT-had, the LOD was 3 genome copies per reaction for amplification conducted for 10–20 min, whereas for RT-LAMP, the LOD was 30–300 genome copies per reaction for a reaction conducted for 40 min. No false-positive results were detected for RT-HDA conducted for 10 to 90 min, but false-positive results occurred when RT-LAMP was conducted for longer than 40 min. We concluded that RT-HDA combined with LFA is more sensitive than RT-LAMP, and it is a good alternative for the development of point-of-care tests for SARS-CoV-2 detection as this method is simple, inexpensive, practical, and does not require qualified personnel to perform the test and interpret its results.
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Affiliation(s)
- Aleksandra Anna Zasada
- Department of Sera and Vaccines Evaluation, National Institute of Public Health NIH—National Research Institute, Chocimska 24, 00-791 Warsaw, Poland
- Correspondence:
| | - Ewa Mosiej
- Department of Sera and Vaccines Evaluation, National Institute of Public Health NIH—National Research Institute, Chocimska 24, 00-791 Warsaw, Poland
| | - Marta Prygiel
- Department of Sera and Vaccines Evaluation, National Institute of Public Health NIH—National Research Institute, Chocimska 24, 00-791 Warsaw, Poland
| | - Maciej Polak
- Department of Sera and Vaccines Evaluation, National Institute of Public Health NIH—National Research Institute, Chocimska 24, 00-791 Warsaw, Poland
| | - Karol Wdowiak
- Department of Sera and Vaccines Evaluation, National Institute of Public Health NIH—National Research Institute, Chocimska 24, 00-791 Warsaw, Poland
| | - Kamila Formińska
- Department of Sera and Vaccines Evaluation, National Institute of Public Health NIH—National Research Institute, Chocimska 24, 00-791 Warsaw, Poland
| | - Robert Ziółkowski
- The Chair of Medical Biotechnology, Faculty of Chemistry, Warsaw University of Technology, 00-664 Warsaw, Poland
| | - Kamil Żukowski
- Centre for Advanced Materials and Technologies CEZAMAT, Warsaw University of Technology, Poleczki 19, 02-822 Warsaw, Poland
| | - Kasper Marchlewicz
- The Chair of Medical Biotechnology, Faculty of Chemistry, Warsaw University of Technology, 00-664 Warsaw, Poland
- Centre for Advanced Materials and Technologies CEZAMAT, Warsaw University of Technology, Poleczki 19, 02-822 Warsaw, Poland
| | - Adam Nowiński
- 2nd Dept of Respiratory Medicine, National Institute of Tuberculosis and Lung, 01-138 Warsaw, Poland
| | - Julia Nowińska
- Faculty of Medicine, Medical University of Warsaw, 02-091 Warsaw, Poland
| | - Waldemar Rastawicki
- Department of Bacteriology and Biocontamination Control, National Institute of Public Health NIH—National Research Institute, 00-791 Warsaw, Poland
| | - Elżbieta Malinowska
- The Chair of Medical Biotechnology, Faculty of Chemistry, Warsaw University of Technology, 00-664 Warsaw, Poland
- Centre for Advanced Materials and Technologies CEZAMAT, Warsaw University of Technology, Poleczki 19, 02-822 Warsaw, Poland
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46
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Allsopp RC, Cowley CM, Barber RC, Jones C, Holmes CW, Bird PW, Gohil SG, Blackmore C, Tobin MD, Brunskill N, Baker PN, Shaw JA. A rapid RT-LAMP SARS-CoV-2 screening assay for collapsing asymptomatic COVID-19 transmission. PLoS One 2022; 17:e0273912. [PMID: 36048856 PMCID: PMC9436079 DOI: 10.1371/journal.pone.0273912] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Accepted: 08/17/2022] [Indexed: 11/18/2022] Open
Abstract
PURPOSE To demonstrate the diagnostic performance of rapid SARS-CoV-2 RT-LAMP assays, comparing the performance of genomic versus sub-genomic sequence target with subsequent application in an asymptomatic screening population. METHODS RT-LAMP diagnostic specificity (DSe) and sensitivity (DSe) was determined using 114 RT-PCR clinically positive and 88 RT-PCR clinically negative swab samples processed through the diagnostic RT-PCR service within the University Hospitals of Leicester NHS Trust. A swab-based RT-LAMP SARS-CoV-2 screening programme was subsequently made available to all staff and students at the University of Leicester (Autumn 2020), implemented to ISO 15189:2012 standards using NHS IT infrastructure and supported by University Hospital Leicester via confirmatory NHS diagnostic laboratory testing of RT-LAMP 'positive' samples. RESULTS Validation samples reporting a Ct < 20 were detected at 100% DSe and DSp, reducing to 95% DSe (100% DSp) for all samples reporting a Ct < 30 (both genomic dual sub-genomic assays). Advisory screening identified nine positive cases in 1680 symptom free individuals (equivalent to 540 cases per 100,000) with results reported back to participants and feed into national statistics within 48 hours. CONCLUSION This work demonstrates the utility of a rapid RT-LAMP assay for collapsing transmission of SARS-CoV-2 in an asymptomatic screening population.
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Affiliation(s)
- Rebecca C. Allsopp
- Leicester Cancer Research Centre, Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Caroline M. Cowley
- Leicester Molecular Diagnostics, Leicester Cancer Research Centre, University of Leicester, Leicester, United Kingdom
| | - Ruth C. Barber
- Leicester Precision Medicine Institute, University of Leicester, Leicester, United Kingdom
| | - Carolyn Jones
- Leicester Precision Medicine Institute, University of Leicester, Leicester, United Kingdom
| | - Christopher W. Holmes
- Clinical Microbiology, University Hospitals of Leicester NHS Trust, Leicester Royal Infirmary, Leicester, United Kingdom
- Department of Respiratory Sciences, University of Leicester, Leicester, United Kingdom
| | - Paul W. Bird
- Clinical Microbiology, University Hospitals of Leicester NHS Trust, Leicester Royal Infirmary, Leicester, United Kingdom
- Department of Respiratory Sciences, University of Leicester, Leicester, United Kingdom
| | - Shailesh G. Gohil
- Leicester Cancer Research Centre, Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Claire Blackmore
- Centre for Environmental Health and Sustainability, University of Leicester, Leicester, United Kingdom
| | - Martin D. Tobin
- Department of Health Sciences, University of Leicester, Leicester, United Kingdom
- Leicester NIHR Biomedical Research Centre, Leicester, United Kingdom
| | - Nigel Brunskill
- Leicester NIHR Biomedical Research Centre, Leicester, United Kingdom
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
| | - Philip N. Baker
- Leicester NIHR Biomedical Research Centre, Leicester, United Kingdom
- College of Life Sciences, University of Leicester, Leicester, United Kingdom
| | - Jacqui A. Shaw
- Leicester Cancer Research Centre, Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
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47
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Lin Q, Jia K, Gou H, He H, Wen J, Shen H, Chen K, Wu Y, Lu B, Liao M, Han Y, Zhang J. A smartphone-assisted high-throughput integrated color-sensing platform for the rapid detection of Campylobacter coli. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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48
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Botella JR. Point-of-Care DNA Amplification for Disease Diagnosis and Management. ANNUAL REVIEW OF PHYTOPATHOLOGY 2022; 60:1-20. [PMID: 36027938 DOI: 10.1146/annurev-phyto-021621-115027] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Early detection of pests and pathogens is of paramount importance in reducing agricultural losses. One approach to early detection is point-of-care (POC) diagnostics, which can provide early warning and therefore allow fast deployment of preventive measures to slow down the establishment of crop diseases. Among the available diagnostic technologies, nucleic acid amplification-based diagnostics provide the highest sensitivity and specificity, and those technologies that forego the requirement for thermocycling show the most potential for use at POC. In this review, I discuss the progress, advantages, and disadvantages of the established and most promising POC amplification technologies. The success and usefulness of POC amplification are ultimately dependent on the availability of POC-friendly nucleic acid extraction methods and amplification readouts, which are also briefly discussed in the review.
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Affiliation(s)
- José R Botella
- Plant Genetic Engineering Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane, Australia;
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49
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Malic L, Brassard D, Da Fonte D, Nassif C, Mounier M, Ponton A, Geissler M, Shiu M, Morton KJ, Veres T. Automated sample-to-answer centrifugal microfluidic system for rapid molecular diagnostics of SARS-CoV-2. LAB ON A CHIP 2022; 22:3157-3171. [PMID: 35670202 DOI: 10.1039/d2lc00242f] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Testing for SARS-CoV-2 is one of the most important assets in COVID-19 management and mitigation. At the onset of the pandemic, SARS-CoV-2 testing was uniquely performed in central laboratories using RT-qPCR. RT-qPCR relies on trained personnel operating complex instrumentation, while time-to-result can be lengthy (e.g., 24 to 72 h). Now, two years into the pandemic, with the surge in cases driven by the highly transmissible Omicron variant, COVID-19 testing capabilities have been stretched to their limit worldwide. Rapid antigen tests are playing an increasingly important role in quelling outbreaks by expanding testing capacity outside the realm of clinical laboratories. These tests can be deployed in settings where repeat and rapid testing is essential, but they often come at the expense of limited accuracy and sensitivity. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) provides a number of advantages to SARS-CoV-2 testing in standard laboratories and at the point-of-need. In contrast to RT-qPCR, RT-LAMP is performed at a constant temperature, which circumvents the need for thermal cycling and translates into a shorter analysis time (e.g., <1 h). In addition, RT-LAMP is compatible with colorimetric detection, facilitating visualization and read-out. However, even with these benefits, RT-LAMP is not yet clinically deployed at its full capacity. Lack of automation and integration of sample preparation, such as RNA extraction, limits the sensitivity and specificity of the method. Furthermore, the need for cold storage of reagents complicates its use at the point of need. The developments presented in this work address these limitations: We describe a fully automated SARS-CoV-2 detection method using RT-LAMP, which also includes up-front lysis and extraction of viral RNA, performed on a centrifugal platform with active pneumatic pumping, a disposable, all-polymer-based microfluidic cartridge and lyophilized reagents. We demonstrate that the limit of detection of the RT-LAMP assay itself is 0.2 copies per μL using N and E genes as target sequences. When combined with integrated RNA extraction, the assay sensitivity is 0.5 copies per μL, which is highly competitive to RT-qPCR. We tested the automated assay using 12 clinical swab specimens from patients and were able to distinguish positive and negative samples for SARS-CoV-2 within 60 min, thereby obtaining 100% agreement with RT-qPCR results.
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Affiliation(s)
- Lidija Malic
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC, J4B 6Y4, Canada.
| | - Daniel Brassard
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC, J4B 6Y4, Canada.
| | - Dillon Da Fonte
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC, J4B 6Y4, Canada.
| | - Christina Nassif
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC, J4B 6Y4, Canada.
| | - Maxence Mounier
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC, J4B 6Y4, Canada.
| | - André Ponton
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC, J4B 6Y4, Canada.
| | - Matthias Geissler
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC, J4B 6Y4, Canada.
| | - Matthew Shiu
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC, J4B 6Y4, Canada.
| | - Keith J Morton
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC, J4B 6Y4, Canada.
| | - Teodor Veres
- Life Sciences Division, National Research Council of Canada, 75 de Mortagne Boulevard, Boucherville, QC, J4B 6Y4, Canada.
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50
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Alhamid G, Tombuloglu H. Perspective Chapter: Recent Progressions on the Colorimetric Diagnosis of SARS-CoV-2 by Loop-Mediated Isothermal Amplification (LAMP) Assay. Infect Dis (Lond) 2022. [DOI: 10.5772/intechopen.105911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Abstract
A simple, fast, and accurate diagnosis of SARS-CoV-2 is of great importance for the patient’s isolation, treatment, and the control of the COVID-19 pandemic. Although RT-qPCR is accepted as the gold standard, studies to improve fast, simple, and more reliable diagnostic methods are continuing. Colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) is a method that allows visual detection of SARS-CoV-2 without needing expensive fluorescence readers. However, the performance of the assay depends on some factors, such as selection of a target gene (i.e., N, RdRp, S, E, M), primer design, the dye used for visual observation—neutral red, calcein, cresol red, or phenol red—and the reaction conditions such as the buffer pH, reaction temperature, and enzyme concentration. In the last 2 years, plenty of research has been conducted to obtain the best performance. In this chapter, the recent progressions on colorimetric RT-LAMP assay for the diagnosis of SARS-CoV-2 are comprehensively elucidated.
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