A new quantitative real-time reverse transcriptase PCR assay and melting curve analysis for detection and genotyping of Ljungan virus strains.
Ljungan virus (LV), a new member of the Picornaviridae, recently isolated from vole species in both Sweden and the USA, is suspected to be pathogenic for humans as an aetiological agent in myocarditis, diabetes, neurological disease and perinatal disease. This study describes for the first time an RT-PCR assay that can identify and quantify LV infection in various tissue sample types using primers and two different minor-groove-binder probes targeting the 5'-untranslated region of the LV genome. The assay, evaluated using control samples derived from various virus cultures and rodent tissues, allows precise quantification of viral load over six orders of magnitude (10(1) to 10(6) viral copies per assay) for all known strains of LV with high sensitivity and specificity. Furthermore, a melting curve analysis (MCA) was developed using two amplicon-specific hybridisation probes that allows rapid genotyping of different LV strains. These new methods provide useful tools to investigate the putative role of LV as a pathogen in both rodents and humans.
Donoso Mantke
Oliver
O
Centre for Biological Safety (ZBS-1), Robert Koch-Institut, Nordufer 20, D-13353 Berlin, Germany. donosoo@rki.de
Kallies
René
R
Niklasson
Bo
B
Nitsche
Andreas
A
Niedrig
Matthias
M
D000818:Animals; D015342:DNA Probes; D005838:Genotype; D006801:Humans; D021141:Nucleic Acid Amplification Techniques; D030061:Parechovirus / Q000235:genetics* / Q000302:isolation & purification*; D010850:Picornaviridae Infections / Q000175:diagnosis / Q000821:virology*; D012367:RNA, Viral / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D044366:Transition Temperature
D015342:DNA Probes; D012367:RNA, Viral