scholarly journals Development of a Reverse Transcriptase Loop-Mediated Isothermal Amplification (LAMP) Assay for the Sensitive Detection of Leishmania Parasites in Clinical Samples

2010 ◽  
Vol 82 (4) ◽  
pp. 591-596 ◽  
Author(s):  
Emily R. Adams ◽  
Al Farazdag Ageed ◽  
Sayda El Safi ◽  
Henk D. F. H. Schallig ◽  
Gerard J. Schoone
Keyword(s):  
Reverse Transcriptase ◽  
Lamp Assay ◽  
Isothermal Amplification ◽  
Sensitive Detection ◽  
Clinical Samples ◽  
Loop Mediated Isothermal Amplification ◽  
Leishmania Parasites

scholarly journals Reverse Transcriptase Loop Mediated Isothermal Amplification (RT-LAMP) for COVID-19 Diagnosis: A Systematic Review and Meta-Analysis

2021 ◽  
Author(s):  
Anita Dominique Subali ◽  
Lowilius Wiyono
Keyword(s):  
Systematic Review ◽  
Reverse Transcriptase ◽  
Quality Assessment ◽  
Meta Analysis ◽  
Lamp Assay ◽  
Isothermal Amplification ◽  
Diagnostic Methods ◽  
Clinical Samples ◽  
Rt Pcr ◽  
Loop Mediated Isothermal Amplification

ABSTRACTBackgroundCoronavirus Disease 2019 (COVID-19) has caused a severe outbreak and become a global public health priority. Rapid increment of infection number along with significant deaths have placed the virus as a serious threat to human health. Rapid, reliable, and simple diagnostic methods are critically essential for disease control. While Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) is the current diagnostic gold standard, Reverse Transcriptase Loop-Mediated Isothermal Amplification (RT-LAMP) appears as a compelling alternative diagnostic test due to its more simplicity, shorter time to result, and lower cost. This study examined RT-LAMP application for rapid identification of SARS-CoV-2 infection compared to RT-PCR assay.MethodsA systematic review and meta-analysis (2020) was conducted in 6 scientific databases following the PRISMA Guideline. Original published studies on human clinical samples in English were included. Articles evaluated sensitivity and specificity of RT-LAMP relative to RT-PCR were considered eligible. Quality assessment of bias and applicability was examined based on QUADAS-2.ResultsA total of 351 studies were found based on the keywords and search queries. 14 eligible case control studies fitted the respective criteria. Quality assessment using QUADAS-2 indicated low risk bias in all included studies. All case studies, comprises 2,112 samples, had the cumulative sensitivity of 95.5% (CI 97.5%=90.8-97.9%) and cumulative specificity of 99.5% (CI 97.5%=97.7-99.9%).ConclusionRT-LAMP assay could be suggested as a reliable alternative COVID-19 diagnostic method with reduced cost and time compared to RT-PCR. RT-LAMP could potentially be utilized during the high-throughput and high-demand critical situations.

scholarly journals Rapid and Extraction-Free Detection of SARS-CoV-2 from Saliva by Colorimetric Reverse-Transcription Loop-Mediated Isothermal Amplification

2020 ◽  
Author(s):  
Matthew A Lalli ◽  
Joshua S Langmade ◽  
Xuhua Chen ◽  
Catrina C Fronick ◽  
Christopher S Sawyer ◽  
...  
Keyword(s):  
Reverse Transcription ◽  
Limit Of Detection ◽  
Colorimetric Assay ◽  
Quantitative Polymerase Chain Reaction ◽  
Rna Extraction ◽  
Lamp Assay ◽  
Isothermal Amplification ◽  
Clinical Samples ◽  
Viral Detection ◽  
Loop Mediated Isothermal Amplification

Abstract Background Rapid, reliable, and widespread testing is required to curtail the ongoing COVID-19 pandemic. Current gold-standard nucleic acid tests are hampered by supply shortages in critical reagents including nasal swabs, RNA extraction kits, personal protective equipment, instrumentation, and labor. Methods To overcome these challenges, we developed a rapid colorimetric assay using reverse-transcription loop-mediated isothermal amplification (RT-LAMP) optimized on human saliva samples without an RNA purification step. We describe the optimization of saliva pretreatment protocols to enable analytically sensitive viral detection by RT-LAMP. We optimized the RT-LAMP reaction conditions and implemented high-throughput unbiased methods for assay interpretation. We tested whether saliva pretreatment could also enable viral detection by conventional reverse-transcription quantitative polymerase chain reaction (RT-qPCR). Finally, we validated these assays on clinical samples. Results The optimized saliva pretreatment protocol enabled analytically sensitive extraction-free detection of SARS-CoV-2 from saliva by colorimetric RT-LAMP or RT-qPCR. In simulated samples, the optimized RT-LAMP assay had a limit of detection of 59 (95% confidence interval: 44–104) particle copies per reaction. We highlighted the flexibility of LAMP assay implementation using 3 readouts: naked-eye colorimetry, spectrophotometry, and real-time fluorescence. In a set of 30 clinical saliva samples, colorimetric RT-LAMP and RT-qPCR assays performed directly on pretreated saliva samples without RNA extraction had accuracies greater than 90%. Conclusions Rapid and extraction-free detection of SARS-CoV-2 from saliva by colorimetric RT-LAMP is a simple, sensitive, and cost-effective approach with broad potential to expand diagnostic testing for the virus causing COVID-19.

scholarly journals Field Verification of an African Swine Fever Virus Loop-Mediated Isothermal Amplification (LAMP) Assay during an Outbreak in Timor-Leste

Viruses ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1444
Author(s):  
Peter T. Mee ◽  
Shani Wong ◽  
Kim J. O’Riley ◽  
Felisiano da Conceição ◽  
Joanita Bendita da Costa Jong ◽  
...  
Keyword(s):  
African Swine Fever Virus ◽  
African Swine Fever ◽  
Lamp Assay ◽  
Fever Virus ◽  
Isothermal Amplification ◽  
Clinical Samples ◽  
Loop Mediated Isothermal Amplification ◽  
Field Verification ◽  
Extraction Step ◽  
Timor Leste

Recent outbreaks of African swine fever virus (ASFV) have seen the movement of this virus into multiple new regions with devastating impact. Many of these outbreaks are occurring in remote, or resource-limited areas, that do not have access to molecular laboratories. Loop-mediated isothermal amplification (LAMP) is a rapid point of care test that can overcome a range of inhibitors. We outline further development of a real-time ASFV LAMP, including field verification during an outbreak in Timor-Leste. To increase field applicability, the extraction step was removed and an internal amplification control (IAC) was implemented. Assay performance was assessed in six different sample matrices and verified for a range of clinical samples. A LAMP detection limit of 400 copies/rxn was determined based on synthetic positive control spikes. A colourmetric LAMP assay was also assessed on serum samples. Comparison of the LAMP assay to a quantitative polymerase chain reaction (qPCR) was performed on clinical ASFV samples, using both serum and oral/rectal swabs, with a substantial level of agreement observed. The further verification of the ASFV LAMP assay, removal of extraction step, implementation of an IAC and the assessment of a range of sample matrix, further support the use of this assay for rapid in-field detection of ASFV.

Development of a Loop-Mediated Isothermal Amplification Assay for Rapid, Sensitive Detection of Campylobacter jejuni in Cattle Farm Samples

2014 ◽  
Vol 77 (9) ◽  
pp. 1593-1598 ◽  
Author(s):  
HEE-JIN DONG ◽  
AE-RI CHO ◽  
TAE-WOOK HAHN ◽  
SEONGBEOM CHO
Keyword(s):  
Campylobacter Jejuni ◽  
Lamp Assay ◽  
Isothermal Amplification ◽  
Sensitive Detection ◽  
Cattle Farm ◽  
Loop Mediated Isothermal Amplification ◽  
Amplification Assay ◽  
Pcr Assays ◽  
Template Dna ◽  
Commercial Kit

Campylobacter jejuni is a leading cause of bacterial foodborne disease worldwide. The detection of this organism in cattle and their environment is important for the control of C. jejuni transmission and the prevention of campylobacteriosis. Here, we describe the development of a rapid and sensitive method for the detection of C. jejuni in naturally contaminated cattle farm samples, based on real-time loop-mediated isothermal amplification (LAMP) of the hipO gene. The LAMP assay was specific (100%inclusivity and exclusivity for 84 C. jejuni and 41 non–C. jejuni strains, respectively), sensitive (detection limit of 100 fg/μl), and quantifiable (R2 = 0.9133). The sensitivity of the LAMP assay was then evaluated for its application to the naturally contaminated cattle farm samples. C. jejuni strains were isolated from 51 (20.7%) of 246 cattle farm samples, and the presence of the hipO gene was tested using the LAMP assay. Amplification of the hipO gene by LAMP within 30 min (mean =10.8 min) in all C. jejuni isolates (n = 51) demonstrated its rapidity and accuracy. Next, template DNA was prepared from a total of 186 enrichment broth cultures of cattle farm samples either by boiling or using a commercial kit, and the sensitivity of detection of C. jejuni was compared between the LAMP and PCR assays. In DNA samples prepared by boiling, the higher sensitivity of the LAMP assay (84.4%) compared with the PCR assay (35.5%) indicates that it is less susceptible to the existence of inhibitors in sample material. In DNA samples prepared using a commercial kit, both the LAMP and PCR assays showed 100% sensitivity. We anticipate that the use of this rapid, sensitive, and simple LAMP assay, which is the first of its kind for the identification and screening of C. jejuni in cattle farm samples, may play an important role in the prevention of C. jejuni contamination in the food chain, thereby reducing the risk of human campylobacteriosis.

scholarly journals A Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

2020 ◽  
Vol 21 (8) ◽  
pp. 2826 ◽  
Author(s):  
Renfei Lu ◽  
Xiuming Wu ◽  
Zhenzhou Wan ◽  
Yingxue Li ◽  
Xia Jin ◽  
...  
Keyword(s):  
Real Time ◽  
Reverse Transcription ◽  
Limit Of Detection ◽  
Lamp Assay ◽  
Isothermal Amplification ◽  
Qpcr Assay ◽  
N Gene ◽  
Clinical Samples ◽  
Loop Mediated Isothermal Amplification ◽  
Specificity And Sensitivity

COVID-19 has become a major global public health burden, currently causing a rapidly growing number of infections and significant morbidity and mortality around the world. Early detection with fast and sensitive assays and timely intervention are crucial for interrupting the spread of the COVID-19 virus (SARS-CoV-2). Using a mismatch-tolerant amplification technique, we developed a simple, rapid, sensitive and visual reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for SARS-CoV-2 detection based on its N gene. The assay has a high specificity and sensitivity, and robust reproducibility, and its results can be monitored using a real-time PCR machine or visualized via colorimetric change from red to yellow. The limit of detection (LOD) of the assay is 118.6 copies of SARS-CoV-2 RNA per 25 μL reaction. The reaction can be completed within 30 min for real-time fluorescence monitoring, or 40 min for visual detection when the template input is more than 200 copies per 25 μL reaction. To evaluate the viability of the assay, a comparison between the RT-LAMP and a commercial RT-qPCR assay was made using 56 clinical samples. The SARS-CoV-2 RT-LAMP assay showed perfect agreement in detection with the RT-qPCR assay. The newly-developed SARS-CoV-2 RT-LAMP assay is a simple and rapid method for COVID-19 surveillance.

Development and evaluation of a reverse transcription-loop-mediated isothermal amplification assay for rapid and high-sensitive detection of Cryptosporidium in water samples

2009 ◽  
Vol 60 (8) ◽  
pp. 2167-2172 ◽  
Author(s):  
A. Inomata ◽  
N. Kishida ◽  
T. Momoda ◽  
M. Akiba ◽  
S. Izumiyama ◽  
...  
Keyword(s):  
Reverse Transcription ◽  
Water Samples ◽  
Cryptosporidium Oocyst ◽  
Lamp Assay ◽  
Test Tube ◽  
Isothermal Amplification ◽  
Sensitive Detection ◽  
Loop Mediated Isothermal Amplification ◽  
Cryptosporidium Oocysts ◽  
Amplification Assay

We describe a novel assay for simple, rapid and high-sensitive detection of Cryptosporidium oocysts in water samples using a reverse transcription-loop-mediated isothermal amplification (RT-LAMP). The assay is based on the detection of 18S rRNA specific for Cryptosporidium oocysts. The detection limit of the developed RT-LAMP assay was as low as 6 × 10−3 oocysts/test tube, which theoretically enables us to detect a Cryptosporidium oocyst and perform duplicated tests even if water samples contain only one oocyst. The developed RT-LAMP assay could more sensitively detect Cryptosporidium oocysts in real water samples than the conventional assay based on microscopic observation.

Sign in / Sign up

Export Citation Format

Share Document