title: Different real-time PCR formats compared for the quantitative detection of human cytomegalovirus DNA.
abstract: BACKGROUND
  The aim of this study was to compare the ABI PRISM 7700 Sequence Detection System and the LightCycler to develop a quantitative real-time PCR assay for the detection of human cytomegalovirus (HCMV) DNA suitable for routine hospital application.
  
  
  METHODS
  We used one exonuclease probe and five different hybridization probe sets as sequence-specific fluorescence detection formats. For the exonuclease assay and two hybridization probe sets, reproducibility and the detection limit were determined. To keep the total assay time to a minimum, we gradually shortened individual reaction steps on both instruments.
  
  
  RESULTS
  The exonuclease assay can be interchangeably performed on the 7700 and the LightCycler. No change of reaction conditions is required, except for the addition of bovine serum albumin to the LightCycler reaction. The shortest possible total assay time is 80 min for the ABI PRISM 7700 Sequence Detection System and 20 min for the LightCycler. When the LightCycler is used, the exonuclease probe can be replaced by a set of hybridization probes. All assays presented here detected HCMV DNA in a linear range from 10(1) to 10(7) HCMV genome equivalents/assay (r >0.995) with low intraassay (<5%) and interassay (<10%) variation.
  
  
  CONCLUSIONS
  The ABI PRISM 7700 Sequence Detection System as well as the LightCycler are useful instruments for rapid and precise online PCR detection. Moreover, the two principles of fluorescence signal production allow HCMV quantification with the same accuracy.
authors.affiliation: Klinik für Innere Medizin m.S. Hämatologie und Onkologie, Charité-Campus Virchow Klinikum, Humboldt Universität, Augustenburger Platz 1, Forschungshaus 37 R 2.303, D-13353 Berlin, Germany. andreas.nitsche@charite.de
authors.forename: A
authors.initials: A
authors.lastname: Nitsche
authors.forename: N
authors.initials: N
authors.lastname: Steuer
authors.forename: C A
authors.initials: CA
authors.lastname: Schmidt
authors.forename: O
authors.initials: O
authors.lastname: Landt
authors.forename: W
authors.initials: W
authors.lastname: Siegert
mesh_terms: D003587:Cytomegalovirus / Q000235:genetics*; D004279:DNA, Viral / Q000097:blood*; D004720:Endonucleases; D005453:Fluorescence; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods; D015203:Reproducibility of Results; D013997:Time Factors
chemical_list: D004279:DNA, Viral; D004720:Endonucleases