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Yin X, Luo H, Zhou H, Zhang Z, Lan Y, Feng Z, Chen W, Zheng H. A rapid isothermal CRISPR-Cas13a diagnostic test for genital herpes simplex virus infection. iScience 2024; 27:108581. [PMID: 38213624 PMCID: PMC10783623 DOI: 10.1016/j.isci.2023.108581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 10/02/2023] [Accepted: 11/23/2023] [Indexed: 01/13/2024] Open
Abstract
Prompt diagnosis is essential for managing herpes simplex virus types 1 and 2 (HSV-1/2). Existing diagnostic methods are not widely available that required expensive or additional equipment for conducting examinations and result readouts, which can limit their utility in resource-constrained settings. We successfully developed a CRISPR-Cas13a-based assay for the detection and genotyping of HSV. Our assay demonstrated a high sensitivity of 96.15% and 95.15% for HSV-1 and HSV-2, respectively, with a specificity of 100% compared to a commercial qPCR assay when tested on 194 clinical samples. Remarkably, the assay enables a limit of detection of 1 copy/μL of viral DNA, facilitated by an enhanced input of RPA product and is designed for both mobile app integration and colorimetric interpretation, allowing for semiquantitative readings. These findings highlight the excellent performance of our CRISPR-based diagnostic in detecting HSV and its potential for point-of-care testing in resource-constrained settings.
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Affiliation(s)
- Xiaona Yin
- Dermatology Hospital, Southern Medical University, Guangzhou 510091, China
- Guangzhou Key Laboratory for Sexually Transmitted Diseases Control, Guangzhou 510091, China
| | - Hao Luo
- Dermatology Hospital, Southern Medical University, Guangzhou 510091, China
- Guangzhou Key Laboratory for Sexually Transmitted Diseases Control, Guangzhou 510091, China
| | - Han Zhou
- Dermatology Hospital, Southern Medical University, Guangzhou 510091, China
- Guangzhou Key Laboratory for Sexually Transmitted Diseases Control, Guangzhou 510091, China
| | - Ziyan Zhang
- Dermatology Hospital, Southern Medical University, Guangzhou 510091, China
- Guangzhou Key Laboratory for Sexually Transmitted Diseases Control, Guangzhou 510091, China
| | - Yinyuan Lan
- Dermatology Hospital, Southern Medical University, Guangzhou 510091, China
- Guangzhou Key Laboratory for Sexually Transmitted Diseases Control, Guangzhou 510091, China
| | - Zhanqin Feng
- Dermatology Hospital, Southern Medical University, Guangzhou 510091, China
- Guangzhou Key Laboratory for Sexually Transmitted Diseases Control, Guangzhou 510091, China
| | - Wentao Chen
- Dermatology Hospital, Southern Medical University, Guangzhou 510091, China
- Guangzhou Key Laboratory for Sexually Transmitted Diseases Control, Guangzhou 510091, China
- Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou 510515, China
| | - Heping Zheng
- Dermatology Hospital, Southern Medical University, Guangzhou 510091, China
- Guangzhou Key Laboratory for Sexually Transmitted Diseases Control, Guangzhou 510091, China
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Promja S, Puenpa J, Achakulvisut T, Poovorawan Y, Lee SY, Athamanolap P, Lertanantawong B. Machine Learning-Assisted Real-Time Polymerase Chain Reaction and High-Resolution Melt Analysis for SARS-CoV-2 Variant Identification. Anal Chem 2023; 95:2102-2109. [PMID: 36633573 PMCID: PMC9843624 DOI: 10.1021/acs.analchem.2c05112] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 12/29/2022] [Indexed: 01/13/2023]
Abstract
Since the declaration of COVID-19 as a pandemic in early 2020, multiple variants of the severe acute respiratory syndrome-related coronavirus (SARS-CoV-2) have been detected. The emergence of multiple variants has raised concerns due to their impact on public health. Therefore, it is crucial to distinguish between different viral variants. Here, we developed a machine learning web-based application for SARS-CoV-2 variant identification via duplex real-time polymerase chain reaction (PCR) coupled with high-resolution melt (qPCR-HRM) analysis. As a proof-of-concept, we investigated the platform's ability to identify the Alpha, Delta, and wild-type strains using two sets of primers. The duplex qPCR-HRM could identify the two variants reliably in as low as 100 copies/μL. Finally, the platform was validated with 167 nasopharyngeal swab samples, which gave a sensitivity of 95.2%. This work demonstrates the potential for use as automated, cost-effective, and large-scale viral variant surveillance.
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Affiliation(s)
- Sutossarat Promja
- Department
of Biomedical Engineering, Faculty of Engineering, Mahidol University, Salaya 73170, Nakhon Pathom, Thailand
| | - Jiratchaya Puenpa
- Center
of Excellence in Clinical Virology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | - Titipat Achakulvisut
- Department
of Biomedical Engineering, Faculty of Engineering, Mahidol University, Salaya 73170, Nakhon Pathom, Thailand
| | - Yong Poovorawan
- Center
of Excellence in Clinical Virology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | - Su Yin Lee
- Faculty
of Applied Sciences, AIMST University, Bedong, Kedah 08100, Malaysia
| | - Pornpat Athamanolap
- Department
of Biomedical Engineering, Faculty of Engineering, Mahidol University, Salaya 73170, Nakhon Pathom, Thailand
- Integrative
Computational BioScience (ICBS) Center, Mahidol University, Salaya 73170, Nakhon Pathom, Thailand
| | - Benchaporn Lertanantawong
- Department
of Biomedical Engineering, Faculty of Engineering, Mahidol University, Salaya 73170, Nakhon Pathom, Thailand
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Tian R, Yan H, Jiang Y, Wu A, Li L, Yang Z, Yu K. Detection and typing of dengue virus by one-step RT-PCR-based high-resolution melting assay. Virus Genes 2022; 58:319-326. [PMID: 35536436 DOI: 10.1007/s11262-022-01906-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 04/04/2022] [Indexed: 11/30/2022]
Abstract
Dengue is a rapidly spreading arboviral disease that can be transmitted through any of the four types of dengue virus (DENV) serotypes. Previous studies have observed that individuals who have a pre-existing secondary infection due to a different dengue serotype, experience severe forms of this disease. During a DENV outbreak, a time-sensitive preliminary diagnosis of the origin of DENV might be useful in controlling the epidemic. Here, we developed a rapid and accurate one-step TB Green RT-PCR-based high-resolution melting (HRM) assay to identify and serotype DENV using serotyping primers based on the alignment with the E gene. This assay had a detection limit of 7.7 × 102 (DENV 1), 3.8 × 102 (DENV 2), 6.2 × 102 (DENV 3), and 1.2 × 103 (DENV 4) RNA copies/mL. No cross-reactivity with the Chikungunya, Zika, and Japanese encephalitis viruses was observed. The feasibility of using this assay for clinical diagnosis was evaluated in DENV-positive patient sera. The HRM assay and the RT-qPCR had complete matched results derived from DENV detection, including 51 serum positive and 20 serum negative. Additionally, eight DENV 2 strains in the same serotype were successfully differentiated by an HRM assay. Thus, this assay facilitated accurate detection and serotyping of DENV, along with the time-sensitive identification of the infectious focus of different DENVs.
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Affiliation(s)
- Rui Tian
- Shangcheng District Center for Disease Control and Prevention, Hangzhou, China
| | - Hao Yan
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Yang Jiang
- Shangcheng District Center for Disease Control and Prevention, Hangzhou, China
| | - Aiping Wu
- Shangcheng District Center for Disease Control and Prevention, Hangzhou, China
| | - Ling Li
- Shangcheng District Center for Disease Control and Prevention, Hangzhou, China
| | - Zhangnv Yang
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China.
| | - Kuangming Yu
- Shangcheng District Center for Disease Control and Prevention, Hangzhou, China.
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Hadi AM, Mohammed Al-Alwany SH, Al-Khafaji ZA, Sharaf M, Mofed D, Khan TU. Molecular diagnosis of Herpes virus type 1 by glycoprotein receptor primers. GENE REPORTS 2022. [DOI: 10.1016/j.genrep.2021.101479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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5
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Azimpour-Ardakan T, Fotouhi-Ardakani R, Hoghooghi-Rad N, Rokni N, Motallebi A. Designing and developing of high-resolution melting technique for separating different types of Toxoplasma gondii by analysis of B1 and ROP8 gene regions. J Microbiol Methods 2021; 184:106188. [PMID: 33713726 DOI: 10.1016/j.mimet.2021.106188] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 03/01/2021] [Accepted: 03/03/2021] [Indexed: 01/31/2023]
Abstract
BACKGROUND Determination of Toxoplasma gondii genotypes plays an important role in the health management and epidemiology of toxoplasmosis. We developed HRM analysis to differentiate genotypes of T. gondii using the B1 and ROP8 genes, through comparing the sensitivity and specificity of both genes and methods used for the detection of T. gondii. METHODS A total of 96 DNA samples of muscle tissue of livestock and poultry brain tissue with three standard strains RH (type I), PRU (type II) and VEG (type III) were prepared and analyzed. Three methods of nested PCR, PCR-PCR and nested-qPCR-HRM were used. Specific new primers were designed and synthesized for developing HRM. Thirty positive samples obtained from nested-qPCR-HRM were sequenced (18 B1 and 12 ROP8). RESULTS Overall, 87 infected samples were identified using both genes. Through the B1 gene, we could separate type I (Tm = 84.8 °C) from II/III types (Tm = 84.6 °C). Also, the ROP8 gene could separate type II (Tm = 84.5 °C) from I/III types (Tm = 84.12 °C). Highest sensitivity (100%) and specificity (78.72%) were observed by nested-qPCR-HRM assays of the B1 and ROP8 genes than by other methods, respectively. Thus, the B1 gene can be used to most accurately detect T. gondii, while the ROP8 gene was more appropriate for T. gondii genotyping. PCR-sequencing results were consistent with HRM results in most selected samples. CONCLUSION HRM analysis is a powerful diagnostic tool for rapid detection and determination of main clonal lineages, and even unusual T. gondii genotypes.
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Affiliation(s)
| | - Reza Fotouhi-Ardakani
- Cellular and Molecular Research Center, Qom University of Medical Sciences, Qom, Iran
| | - Nasser Hoghooghi-Rad
- Parasitology Department, School of Specialized Science of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Nourdehr Rokni
- Department of Hygiene, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Abbasali Motallebi
- Department of Hygiene, Science and Research Branch, Islamic Azad University, Tehran, Iran.
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Grosche L, Mühl-Zürbes P, Ciblis B, Krawczyk A, Kuhnt C, Kamm L, Steinkasserer A, Heilingloh CS. Herpes Simplex Virus Type-2 Paralyzes the Function of Monocyte-Derived Dendritic Cells. Viruses 2020; 12:E112. [PMID: 31963276 PMCID: PMC7019625 DOI: 10.3390/v12010112] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/09/2020] [Accepted: 01/14/2020] [Indexed: 12/13/2022] Open
Abstract
Herpes simplex viruses not only infect a variety of different cell types, including dendritic cells (DCs), but also modulate important cellular functions in benefit of the virus. Given the relevance of directed immune cell migration during the initiation of potent antiviral immune responses, interference with DC migration constitutes a sophisticated strategy to hamper antiviral immunity. Notably, recent reports revealed that HSV-1 significantly inhibits DC migration in vitro. Thus, we aimed to investigate whether HSV-2 also modulates distinct hallmarks of DC biology. Here, we demonstrate that HSV-2 negatively interferes with chemokine-dependent in vitro migration capacity of mature DCs (mDCs). Interestingly, rather than mediating the reduction of the cognate chemokine receptor expression early during infection, HSV-2 rapidly induces β2 integrin (LFA-1)-mediated mDC adhesion and thereby blocks mDC migration. Mechanistically, HSV-2 triggers the proteasomal degradation of the negative regulator of β2 integrin activity, CYTIP, which causes the constitutive activation of LFA-1 and thus mDC adhesion. In conclusion, our data extend and strengthen recent findings reporting the reduction of mDC migration in the context of a herpesviral infection. We thus hypothesize that hampering antigen delivery to secondary lymphoid organs by inhibition of mDC migration is an evolutionary conserved strategy among distinct members of Herpesviridae.
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Affiliation(s)
- Linda Grosche
- Department of Immune Modulation, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91052 Erlangen, Germany
| | - Petra Mühl-Zürbes
- Department of Immune Modulation, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91052 Erlangen, Germany
| | - Barbara Ciblis
- Department of Immune Modulation, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91052 Erlangen, Germany
| | - Adalbert Krawczyk
- Department of Infectious Diseases, University Hospital Essen, University of Duisburg-Essen, D-45147 Essen, Germany
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, D-45147 Essen, Germany
| | - Christine Kuhnt
- Department of Immune Modulation, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91052 Erlangen, Germany
| | - Lisa Kamm
- Department of Immune Modulation, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91052 Erlangen, Germany
| | - Alexander Steinkasserer
- Department of Immune Modulation, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91052 Erlangen, Germany
| | - Christiane Silke Heilingloh
- Department of Immune Modulation, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91052 Erlangen, Germany
- Department of Infectious Diseases, University Hospital Essen, University of Duisburg-Essen, D-45147 Essen, Germany
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Sun Y, Cheng Y, Lin P, Zhang H, Yi L, Tong M, Cao Z, Li S, Cheng S, Wang J. Simultaneous detection and differentiation of canine parvovirus and feline parvovirus by high resolution melting analysis. BMC Vet Res 2019; 15:141. [PMID: 31077252 PMCID: PMC6511188 DOI: 10.1186/s12917-019-1898-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 05/02/2019] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Canine parvovirus (CPV) and feline parvovirus (FPV) are causative agents of diarrhea in dogs and cats, which manifests as depression, vomiting, fever, loss of appetite, leucopenia, and diarrhea in young animals. CPV and FPV can single or mixed infect cats and cause disease. To diagnose sick animals effectively, an effective virus diagnostic and genome typing method with high sensitivity and specificity is required. RESULTS In this study, a conserved segment containing one SNP A4408C of parvovirus was used for real-time PCR amplification. Subsequently, data were auto-analyzed and plotted using Applied Biosystems® High Resolution Melt Software v3.1. Results showed that CPV and FPV can be detected simultaneously in a single PCR reaction. No cross-reactions were observed with canine adenovirus, canine coronavirus, and canine distemper virus. The assay had a detection limit of 4.2 genome copies of CPV and FPV. A total of 80 clinical samples were subjected to this assay, as well as to conventional PCR-sequence assay and virus isolation. Results showed that the percentage of agreement of the assay and other methods are high. CONCLUSIONS In short, we have developed a diagnostic test for the accurate detection and differentiation of CPV and FPV in fecal samples, which is also cost effective.
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Affiliation(s)
- Yaru Sun
- Key Laboratory of Special Animal Epidemic Disease, Ministry of Agriculture, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China.,Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China
| | - Yuening Cheng
- Key Laboratory of Special Animal Epidemic Disease, Ministry of Agriculture, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China.,Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China
| | - Peng Lin
- Key Laboratory of Special Animal Epidemic Disease, Ministry of Agriculture, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China.,Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China
| | - Hewei Zhang
- Key Laboratory of Special Animal Epidemic Disease, Ministry of Agriculture, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China.,Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China
| | - Li Yi
- Key Laboratory of Special Animal Epidemic Disease, Ministry of Agriculture, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China.,Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China
| | - Mingwei Tong
- Key Laboratory of Special Animal Epidemic Disease, Ministry of Agriculture, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China.,Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China
| | - Zhigang Cao
- Key Laboratory of Special Animal Epidemic Disease, Ministry of Agriculture, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China.,Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China
| | - Shuang Li
- Key Laboratory of Special Animal Epidemic Disease, Ministry of Agriculture, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China.,Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China
| | - Shipeng Cheng
- Key Laboratory of Special Animal Epidemic Disease, Ministry of Agriculture, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China.,Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China
| | - Jianke Wang
- Key Laboratory of Special Animal Epidemic Disease, Ministry of Agriculture, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China. .,Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, No. 4899, Juye Street, Jingyue District, Changchun, 130112, People's Republic of China.
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Detection and Differentiation of Two Koala Gammaherpesviruses by Use of High-Resolution Melt (HRM) Analysis Reveals Differences in Viral Prevalence and Clinical Associations in a Large Study of Free-Ranging Koalas. J Clin Microbiol 2019; 57:JCM.01478-18. [PMID: 30626662 DOI: 10.1128/jcm.01478-18] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 12/21/2018] [Indexed: 12/27/2022] Open
Abstract
The iconic koala (Phascolarctos cinereus) is host to two divergent gammaherpesviruses, phascolarctid gammaherpesviruses 1 and 2 (PhaHV-1 and -2), but the clinical significance of the individual viruses is unknown and current diagnostic methods are unsuitable for differentiating between the viruses in large-scale studies. To address this, we modified a pan-herpesvirus nested PCR to incorporate high-resolution melt analysis. We applied this assay in a molecular epidemiological study of 810 koalas from disparate populations across Victoria, Australia, including isolated island populations. Animal and clinical data recorded at sampling were analyzed and compared to infection status. Between populations, the prevalence of PhaHV-1 and -2 varied significantly, ranging from 1% to 55%. Adult and older animals were 5 to 13 times more likely to be positive for PhaHV-1 than juveniles (P < 0.001), whereas PhaHV-2 detection did not change with age, suggesting differences in how these two viruses are acquired over the life of the animal. PhaHV-1 detection was uniquely associated with the detection of koala retrovirus, particularly in females (P = 0.008). Both viruses were significantly associated (P < 0.05) with the presence of genital tract abnormalities (uterine/ovarian cysts and testicular malformation), reduced fertility in females, urinary incontinence, and detection of Chlamydia pecorum, although the strength of these associations varied by sex and virus. Understanding the clinical significance of these viruses and how they interact with other pathogens will inform future management of threatened koala populations.
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Pallandre L, Lesne M, de Boisséson C, Charrier A, Daniel P, Tragnan A, Debeuf B, Chesneau V, Bigarré L. Genetic identification of two Acipenser iridovirus-European variants using high-resolution melting analysis. J Virol Methods 2018; 265:105-112. [PMID: 30586558 DOI: 10.1016/j.jviromet.2018.12.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 11/23/2018] [Accepted: 12/15/2018] [Indexed: 11/19/2022]
Abstract
Acipenser iridovirus-European (AcIV-E) is an important pathogen of sturgeons. Two variants differing by single-nucleotide polymorphisms (SNP) in the Major Capsid Protein gene have been described, but without any indication as to their prevalence in farms. To facilitate epidemiological studies, we developed a high-resolution melting (HRM) assay to distinguish between two alleles (var1 and var2) differing by five point substitutions. The HRM assay detected as little as 100 copies of plasmids harboring cloned sequences of var1 and var2, which have melting temperatures (Tm) differing by only 1 °C. The assay was specific of AcIV-E as demonstrated by the absence of signal when testing a related, yet distinct, virus as well as DNA from an AcIV-E-negative sturgeon sample. Experiments with mixtures of two distinct plasmids revealed abnormal melting curve patterns, which showed dips just before the main melting peaks. These dips in the curves were interpreted as the dissociation of heteroduplexes fortuitously created during the PCR step. Screening AciV-E-positive field samples of Russian sturgeons from three farms revealed the presence of var2, based on the Tm. However, for a few samples, the melting curves showed patterns typical of var2 as the dominant viral genome, mixed with another minor variant which proved to be var1. In conclusion, HRM is a simple method to screen for AcIV-E var1 and var2 and can be used on a large scale in Europe to trace these two variants which likely represent two genetic lineages.
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Affiliation(s)
- Laurane Pallandre
- Laboratoire de Ploufragan-Plouzané, ANSES, Technopole Brest Iroise, 29280 Plouzané, France
| | - Mélanie Lesne
- Laboratoires des Pyrénées et des Landes, 40004, Mont-de-Marsan, France
| | - Claire de Boisséson
- Laboratoire de Ploufragan-Plouzané, ANSES, rue des fusillés, 22440, Ploufragan, France
| | - Amélie Charrier
- Laboratoires des Pyrénées et des Landes, 40004, Mont-de-Marsan, France
| | - Patrick Daniel
- Laboratoires des Pyrénées et des Landes, 40004, Mont-de-Marsan, France
| | - Arthur Tragnan
- Groupement de Défense Sanitaire Aquacole Aquitain, 40004, Mont-de-Marsan, France
| | | | | | - Laurent Bigarré
- Laboratoire de Ploufragan-Plouzané, ANSES, Technopole Brest Iroise, 29280 Plouzané, France.
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10
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A potential association between mutations in the iNOS cDNA 3′ stretch and oral squamous cell carcinoma - A preliminary study. Meta Gene 2018. [DOI: 10.1016/j.mgene.2018.02.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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