tetano
Editor, Senior Moderator
J Mol Diagn. 2011 Jan;13(1):100-7. Epub 2010 Dec 23.
Development and Evaluation of Reverse Transcription Loop-Mediated Isothermal Amplification Assay for Rapid and Real-Time Detection of the Swine-Origin Influenza A H1N1 Virus.
Parida M, Shukla J, Sharma S, Ranghia Santhosh S, Ravi V, Mani R, Thomas M, Khare S, Rai A, Kant Ratho R, Pujari S, Mishra B, Lakshmana Rao PV, Vijayaraghavan R.
Division of Virology, Defence Research & Development Establishment, Gwalior, India.
Abstract
The recent emergence of the swine-origin influenza A H1N1 virus (S-OIV) poses a serious global health threat. Rapid detection and differentiation of S-OIV from seasonal influenza is crucial for patient management and control of the epidemics. A one-step, single-tube accelerated and quantitative S-OIV-specific H1 reverse transcription loop-mediated isothermal amplification (RTLAMP) assay for clinical diagnosis of S-OIV by targeting the H1 gene is reported in this article. A comparative evaluation of the H1-specific RTLAMP assay vis-?-vis the World Health Organization-approved real-time polymerase chain reaction (RTPCR), involving 239 acute-phase throat swab samples, demonstrated exceptionally higher sensitivity by picking up all of the 116 H1N1-positive cases and 36 additional positive cases among the negatives that were sequence-confirmed as S-OIV H1N1. None of the real-time RTPCR-positive samples were missed by the RTLAMP system. The comparative analysis revealed that S-OIV RTLAMP was up to tenfold more sensitive than the World Health Organization real-time RTPCR; it had a detection limit of 0.1 tissue culture infectious dosage of (50)/ml. One of the most attractive features of this isothermal gene amplification assay is that it seems to have an advantage in monitoring gene amplification by means of SYBR Green I dye-mediated naked-eye visualization within 30 minutes compared to 2 to 3 hours for a real-time reverse transcription polymerase chain reaction. This suggests that the RTLAMP assay is a valuable tool for rapid, real-time detection and quantification of S-OIV in acute-phase throat swab samples without requiring sophisticated equipment.
Copyright © 2011 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.
PMID: 21227400 [PubMed - in process]
http://www.ncbi.nlm.nih.gov/pubmed/21227400
Development and Evaluation of Reverse Transcription Loop-Mediated Isothermal Amplification Assay for Rapid and Real-Time Detection of the Swine-Origin Influenza A H1N1 Virus.
Parida M, Shukla J, Sharma S, Ranghia Santhosh S, Ravi V, Mani R, Thomas M, Khare S, Rai A, Kant Ratho R, Pujari S, Mishra B, Lakshmana Rao PV, Vijayaraghavan R.
Division of Virology, Defence Research & Development Establishment, Gwalior, India.
Abstract
The recent emergence of the swine-origin influenza A H1N1 virus (S-OIV) poses a serious global health threat. Rapid detection and differentiation of S-OIV from seasonal influenza is crucial for patient management and control of the epidemics. A one-step, single-tube accelerated and quantitative S-OIV-specific H1 reverse transcription loop-mediated isothermal amplification (RTLAMP) assay for clinical diagnosis of S-OIV by targeting the H1 gene is reported in this article. A comparative evaluation of the H1-specific RTLAMP assay vis-?-vis the World Health Organization-approved real-time polymerase chain reaction (RTPCR), involving 239 acute-phase throat swab samples, demonstrated exceptionally higher sensitivity by picking up all of the 116 H1N1-positive cases and 36 additional positive cases among the negatives that were sequence-confirmed as S-OIV H1N1. None of the real-time RTPCR-positive samples were missed by the RTLAMP system. The comparative analysis revealed that S-OIV RTLAMP was up to tenfold more sensitive than the World Health Organization real-time RTPCR; it had a detection limit of 0.1 tissue culture infectious dosage of (50)/ml. One of the most attractive features of this isothermal gene amplification assay is that it seems to have an advantage in monitoring gene amplification by means of SYBR Green I dye-mediated naked-eye visualization within 30 minutes compared to 2 to 3 hours for a real-time reverse transcription polymerase chain reaction. This suggests that the RTLAMP assay is a valuable tool for rapid, real-time detection and quantification of S-OIV in acute-phase throat swab samples without requiring sophisticated equipment.
Copyright © 2011 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.
PMID: 21227400 [PubMed - in process]
http://www.ncbi.nlm.nih.gov/pubmed/21227400