title: Visual detection of the human metapneumovirus using reverse transcription loop-mediated isothermal amplification with hydroxynaphthol blue dye.
abstract: BACKGROUND
  Human metapneumovirus (hMPV) is a major cause of acute respiratory infections ranging from wheezing to bronchiolitis and pneumonia in children worldwide. The objective of this study is to develop a visual reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for the detection of hMPV and applied to the clinical samples.
  
  
  RESULTS
  In this study, visual RT-LAMP assay for hMPV was performed in one step with the addition of hydroxynaphthol blue (HNB), and were used to detect respiratory samples. Six primers, including two outer primers (F3 and B3), two inner primers (FIP, BIP) and two loop primers (LF and LB), were designed for hMPV N gene by the online software. Moreover, the RT-LAMP assay showed good specificity and no cross-reactivity was observed with human rhinovirus (HRV), human respiratory syncytial Virus (RSV), or influenza virus A/PR/8/34 (H1N1). The detection limit of the RT-LAMP assay was approximately ten viral RNA copies, lower than that of traditional reverse transcriptase polymerase chain reaction (RT-PCR) 100 RNA copies. In the 176 nasopharyngeal samples, 23 (13.1%) were conformed as hMPV positive by RT-LAMP, but 18 (10.2%) positive by RT-PCR.
  
  
  CONCLUSIONS
  Compared with conventional RT-PCR, the visual hMPV RT-LAMP assay performed well in the aspect of detect time, sensitivity, specificity and visibility. It is anticipated that the RT-LAMP will be used for clinical tests in hospital or field testing during outbreaks and in emergency.
authors: State Key Laboratory for Molecular Virology and Genetic Engineering, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Ying-Xin Road 100, Xuan Wu District, Beijing, 100052, Peoples Republic of China.
authors: Xiang
authors: X
authors: Wang
authors: Qian
authors: Q
authors: Zhang
authors: Fang
authors: F
authors: Zhang
authors: Fenlian
authors: F
authors: Ma
authors: Wenzhi
authors: W
authors: Zheng
authors: Zhihui
authors: Z
authors: Zhao
authors: Yinglong
authors: Y
authors: Bai
authors: Lishu
authors: L
authors: Zheng
mesh_terms: D000293:Adolescent; D001483:Base Sequence; D002648:Child; D002675:Child, Preschool; D002681:China; D004396:Coloring Agents; D017931:DNA Primers / Q000737:chemistry / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D029121:Metapneumovirus / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D009282:Naphthalenesulfonates / Q000032:analysis; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D018184:Paramyxoviridae Infections / Q000175:diagnosis / Q000821:virology*; D048348:Reverse Transcription; D014764:Viral Proteins / Q000235:genetics
chemical_list: D004396:Coloring Agents; D017931:DNA Primers; D009282:Naphthalenesulfonates; D014764:Viral Proteins; C540250:trisodium 3-hydroxy-4-((2Z)-2-(2-oxo-4-sulfonatonaphthalen-1-ylidene)hydrazinyl)naphthalene-2,7-disulfonate