Browsing by Author "Drexler, Jan Felix"

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    Close Relative of Human Middle East Respiratory Syndrome Coronavirus in Bat, South Africa
    (Centers for Disease Control and Prevention (CDC), 2013-10) Ithete, Ndapewa Laudika; Stoffberg, Samantha; Corman, Victor Max; Cottontail, Veronika M.; Richards, Leigh Rosanne; Schoeman, M. Corrie; Drosten, Christian; Drexler, Jan Felix; Preiser, Wolfgang
    We now report the identification of a South Africa bat derived CoV that has an even closer phylogenetic relationship with MERS-CoV.
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    Evidence for novel hepaciviruses in rodents
    (PLoS, 2013-06-20) Drexler, Jan Felix; Corman, Victor Max; Muller, Marcel Alexander; Lukashev, Alexander N.; Gmyl, Anatoly; Coutard, Bruno; Adam, Alexander; Ritz, Daniel; Leijten, Lonneke M.; Matthee, Sonja; Van Riel, Debby; Kallies, Rene; Klose, Stefan M.; Gloza-Rausch, Florian; Binger, Tabea; Annan, Augustina; Adu-Sarkodie, Yaw; Oppong, Samuel; Bourgarel, Mathieu; Rupp, Daniel; Hoffmann, Bernd; Schlegel, Mathias; Kummerer, Beate M.; Kruger, Detlev H.; Schmidt-Chanasit, Jonas; Setien, Alvaro Aguilar; Cottontail, Veronika M.; Hemachudha, Thiravat; Wacharapluesadee, Supaporn; Osterrieder, Klaus; Bartenschlager, Ralf; Beer, Martin; Kuiken, Thijs; Reusken, Chantal; Leroy, Eric M.; Ulrich, Rainer G.; Drosten, Christian
    Hepatitis C virus (HCV) is among the most relevant causes of liver cirrhosis and hepatocellular carcinoma. Research is complicated by a lack of accessible small animal models. The systematic investigation of viruses of small mammals could guide efforts to establish such models, while providing insight into viral evolutionary biology. We have assembled the so-far largest collection of small-mammal samples from around the world, qualified to be screened for bloodborne viruses, including sera and organs from 4,770 rodents (41 species); and sera from 2,939 bats (51 species). Three highly divergent rodent hepacivirus clades were detected in 27 (1.8%) of 1,465 European bank voles (Myodes glareolus) and 10 (1.9%) of 518 South African four-striped mice (Rhabdomys pumilio). Bats showed anti-HCV immunoblot reactivities but no virus detection, although the genetic relatedness suggested by the serologic results should have enabled RNA detection using the broadly reactive PCR assays developed for this study. 210 horses and 858 cats and dogs were tested, yielding further horse-associated hepaciviruses but none in dogs or cats. The rodent viruses were equidistant to HCV, exceeding by far the diversity of HCV and the canine/equine hepaciviruses taken together. Five full genomes were sequenced, representing all viral lineages. Salient genome features and distance criteria supported classification of all viruses as hepaciviruses. Quantitative RT-PCR, RNA in-situ hybridisation, and histopathology suggested hepatic tropism with liver inflammation resembling hepatitis C. Recombinant serology for two distinct hepacivirus lineages in 97 bank voles identified seroprevalence rates of 8.3 and 12.4%, respectively. Antibodies in bank vole sera neither cross-reacted with HCV, nor the heterologous bank vole hepacivirus. Co-occurrence of RNA and antibodies was found in 3 of 57 PCR-positive bank vole sera (5.3%). Our data enable new hypotheses regarding HCV evolution and encourage efforts to develop rodent surrogate models for HCV.
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    HIV-1 viral load assays for resource-limited settings : clades matter
    (Public Library of Science Medicine, 2006-12) Preiser, Wolfgang; Drexler, Jan Felix; Drosten, Christian
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    Ultrasensitive monitoring of HIV-1 viral load by a low-cost real-time reverse transcription-PCR assay with internal control for the 5' long terminal repeat domain
    (American Association for Clinical Chemistry, 2006-04) Drosten, Christian; Panning, Marcus; Drexler, Jan Felix; Hänsel, Florian; Pedroso, Celia; Yeats, Jane; Samuel, Matthew; Liedigk, Britta; Lippert, Ute; Stürmer, Martin; Doerr, Hans Wilhelm; Brites, Carlos; Preiser, Wolfgang; De Souza Luna, Luciano Kleber
    BACKGROUND: Current HIV-1 viral-load assays are too expensive for resource-limited settings. In some countries, monitoring of antiretroviral therapy is now more expensive than treatment itself. In addition, some commercial assays have shown shortcomings in quantifying rare genotypes. METHODS: We evaluated real-time reverse transcription-PCR with internal control targeting the conserved long terminal repeat (LTR) domain of HIV-1 on reference panels and patient samples from Brazil (n = 1186), South Africa (n = 130), India (n = 44), and Germany (n = 127). RESULTS: The detection limit was 31.9 IU of HIV-1 RNA/mL of plasma (> 95% probability of detection, Probit analysis). The internal control showed inhibition in 3.7% of samples (95% confidence interval, 2.32%-5.9%; n = 454; 40 different runs). Comparative qualitative testing yielded the following: Roche Amplicor vs LTR assay (n = 431 samples), 51.7% vs 65% positives; Amplicor Ultrasensitive vs LTR (n = 133), 81.2% vs 82.7%; BioMerieux NucliSens HIV-1 QT (n = 453), 60.5% vs 65.1%; Bayer Versant 3.0 (n = 433), 57.7% vs 55.4%; total (n = 1450), 59.0% vs 63.8% positives. Intra-/interassay variability at medium and near-negative concentrations was 18%-51%. The quantification range was 50-10,000,000 IU/mL. Viral loads for subtypes A-D, F-J, AE, and AG yielded mean differences of 0.31 log(10) compared with Amplicor in the 10(3)-10(4) IU/mL range. HIV-1 N and O were not detected by Amplicor, but yielded up to 180 180.00 IU/mL in the LTR assay. Viral loads in stored samples from all countries, compared with Amplicor, NucliSens, or Versant, yielded regression line slopes (SD) of 0.9 (0.13) (P < 0.001 for all). CONCLUSIONS: This method offers all features of commercial assays and covers all relevant genotypes. It could allow general monitoring of antiretroviral therapy in resource-limited settings.