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10. In Response: Getting the measure of hepatitis A virus (HAV): A better understanding of the RNA content of HAV reference material and blood donations.

Author

Baylis, Sally A., Chudy, Michael, and Blümel, Johannes

Subjects
*HEPATITIS A virus, *HEPATITIS viruses, *VIRAL hepatitis, *REFERENCE sources, *RNA
Abstract

This article discusses the characterization of hepatitis A virus (HAV) RNA-positive blood donations during an epidemic in Poland. The study used two nucleic acid amplification technique (NAT)-based methods to screen the donations for HAV RNA. The sensitivity of the two methods was found to be very similar and extremely sensitive. The article also discusses the evaluation of the 1st World Health Organization (WHO) International Standard (IS) for HAV RNA and the use of RT-droplet digital PCR (RT-ddPCR) to determine the HAV RNA content of the IS. The study found that the IU:copy number ratio of the IS was significantly higher than previously reported, suggesting limitations in the sensitivities of the methods used to determine the potency of the IS. The article concludes by highlighting the importance of understanding the HAV RNA load in transfusion transmission and the need for further research in this area. The study was supported by funding from the German Ministry of Health and the authors declare no conflicts of interest. [Extracted from the article]

Published
2024
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12. Second hepatitis C virus transmission by blood components since introduction of mandatory NAT screening in Germany.

Author

Himmelsbach, Kiyoshi, Mueller, Susanne, Kress, Julia, Fiedler, Sarah A., Miskey, Csaba, Ivics, Zoltan, Patek, Alexander, and Chudy, Michael

Subjects
HEPATITIS C virus, NUCLEIC acid amplification techniques, PLASMA products, HEPATITIS C, BLOOD products, VIRAL transmission, BLOOD transfusion reaction
Abstract

Background: Viral safety of blood products in Germany has improved significantly over the last two decades. We describe the second documented transfusion‐transmitted (TT) episode for the hepatitis C virus (HCV) in Germany since mandatory nucleic acid amplification techniques (NAT) screening was introduced in 1999. Study Design and Methods: When a repeat donor who had tested negative for anti‐HCV tested positive for HCV RNA by NAT in a minipool (MP) of eight, a look‐back procedure was initiated. Qualitative, quantitative and genotyping assays were used to investigate the titers of the quarantined fresh frozen plasma (FFP) from the donor and a serum sample from the recipient of the pooled platelet concentrate (PPC). Amplified products of 5'UTR and HVR1 were used for sequence comparison to characterize the HCV genomic identity of donor and recipient samples. Results: All NAT tests utilized in this procedure were able to detect a low HCV RNA titer (~15 IU/ml) in the FFP from the donation. Dilution of FFP by factor 8 was performed to mimic an MP, and the detection rate correlated well with the claimed sensitivity of the tests. Analysis of donor and recipient samples revealed genotype 3a viral transmission confirmed by sequence analysis. Conclusion: This TT HCV case could have been prevented by individual donation (ID) NAT. However, a low titer blood donation in the window period (WP) is very rare. Residual risk calculation for TT HCV in the WP revealed that, compared to MP‐NAT testing, ID‐NAT would improve blood safety only marginally. [ABSTRACT FROM AUTHOR]

Published
2023
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13. Genome Sequences of West Nile Virus Reference Materials

Author

Roth, Hanna, primary, Kreß, Julia, additional, Chudy, Michael, additional, Blümel, Johannes, additional, Schmidt-Chanasit, Jonas, additional, Cadar, Dániel, additional, Niedrig, Matthias, additional, Ferenczi, Emőke, additional, Herrmann, Maike, additional, Baylis, Sally A., additional, and Miskey, Csaba, additional

Published
2021
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18. First transmission of human immunodeficiency virus Type 1 by a cellular blood product after mandatory nucleic acid screening in Germany

Author

Schmidt, Michael, Korn, Klaus, Nübling, Micha C., Chudy, Michael, Kress, Julia, Horst, Heinz A., Geusendam, Geert, Hennig, Holger, Sireis, Walid, Rabenau, Holger F., Doerr, Hans Wilhelm, Berger, Annemarie, Hourfar, Michael Kai, Gubbe, Knut, Karl, Andreas, Fickenscher, Helmut, Tischer, Karsten B., Babiel, Reiner, Seifried, Erhard, and Gürtler, Lutz

Published
2009
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29. Human immunodeficiency virus 1 dual-target nucleic acid technology improves blood safety: 5 years of experience of the German Red Cross blood donor service Baden-Württemberg-Hessen

Author

Hourfar, Kai, primary, Eberle, Josef, additional, Müller, Markus, additional, Micha Nübling, C, additional, Chudy, Michael, additional, Kress, Julia, additional, Gürtler, Lutz, additional, Mayr-Wohlfart, Uschi, additional, Schrezenmeier, Hubert, additional, Hellmann, Inke, additional, Luhm, Jürgen, additional, Kraas, Sabine, additional, Ringwald, Jürgen, additional, Gubbe, Knut, additional, Frank, Kerstin, additional, Karl, Andreas, additional, Tonn, Torsten, additional, Jaeger, Maike, additional, Sireis, Walid, additional, Seifried, Erhard, additional, and Schmidt, Michael, additional

Published
2018
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32. Blood donor screening for West Nile virus (WNV) revealed acute Usutu virus (USUV) infection, Germany, September 2016

Author

Cadar, Daniel, primary, Maier, Philipp, additional, Müller, Susanne, additional, Kress, Julia, additional, Chudy, Michael, additional, Bialonski, Alexandra, additional, Schlaphof, Alexander, additional, Jansen, Stephanie, additional, Jöst, Hanna, additional, Tannich, Egbert, additional, Runkel, Stefan, additional, Hitzler, Walter E, additional, Hutschenreuter, Gabriele, additional, Wessiepe, Martina, additional, and Schmidt-Chanasit, Jonas, additional

Published
2017
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34. Highly selective optical-sensing membranes, containing calix[4]arene chromoionophores, for Pb2+ ions

Author

van der Veen, N.J., Rozniecka, Ewa, Woldering, L.A., Chudy, M., Chudy, Michael, Huskens, Jurriaan, van Veggel, F.C.J.M., Reinhoudt, David, Faculty of Science and Technology, and Molecular Nanofabrication

Subjects
lead, Ion exchange, optode membrane, Ligand, Chemistry, Sensors, Metal ions in aqueous solution, METIS-202982, Organic Chemistry, Inorganic chemistry, General Chemistry, IR-36760, Catalysis, Ion, Membrane, chromoionophore, Bathochromic shift, Hypsochromic shift, Absorption (chemistry), Calixarenes
Abstract

Plasticized poly(vinyl chloride) (PVC) optode membranes containing novel calix[4]arene chromoionophores 1 or 2 and one equivalent of a lipophilic anion respond to Pb2+ ions with high selectivity over alkali, alkaline-earth, and other heavy metal ions. This selectivity stems from the combination of ligand specificity and a unique ion exchange scheme that employs both monovalent metal ions and protons as the exchanged ions. Complexation of Pb2+ ions inside the membrane is accompanied by deprotonation of the chromoionophores, which causes a bathochromic shift of the absorption maximum h-max. The response to Pb2+ ions is modulated by pH and alkali metal ions in a fashion that is consistent with the proposed ion-exchange mechanism. Of all of the other metal ions tested, only Cs+ and Ag+ produce a color change. However, these monovalent metal ions cause hypsochromic shifts of h-max instead of the bathochromic shift caused by Pb2+, because the chromoionophores remain protonated upon complexation.

Published
2001

36. HBsAg non-reactive HBV infection in blood donors:Transmission and pathogenicity

Author

Gerlich, Wolfram H., Wagner, Franz F., Chudy, Michael, Harritshoj, Lene Holm, Lattermann, Annette, Wienzek, Sandra, Glebe, Dieter, Saniewski, Mona, Schüttler, Christian G., Wend, Ulrike C., Willems, Wulf R., Bauerfeind, Ursula, Jork, Christine, Bein, Gregor, Platz, Per, Ullum, Henrik, Dickmeiss, Ebbe, Gerlich, Wolfram H., Wagner, Franz F., Chudy, Michael, Harritshoj, Lene Holm, Lattermann, Annette, Wienzek, Sandra, Glebe, Dieter, Saniewski, Mona, Schüttler, Christian G., Wend, Ulrike C., Willems, Wulf R., Bauerfeind, Ursula, Jork, Christine, Bein, Gregor, Platz, Per, Ullum, Henrik, and Dickmeiss, Ebbe

Abstract

Five blood donors with occult persistent and one donor with an early window phase HBV infection were identified. They were negative in regular HBsAg screening and had low levels of HBV DNA that were probably not detectable by current mini-pool nucleic acid amplification testing. In four donors several mutations were found located in the HBs antigen loop. In three donors the mutations were predominantly outside the "a" determinant; one donor had a wild type HBsAg sequence. Fifty-five recipients of donations from the persistently infected donors could be tested for previous or ongoing HBV infection and of them 53% (29/55) were anti-HBc positive. Based on the prevalence of anti-HBc in Germany (7%), it was assumed that four of those recipients had already been positive before transfusion. In 22 cases, it was assumed that they acquired infection by the donations, but the infection remained asymptomatic and was resolved. In three cases transmission was proven by the time course of the acute infection and sequence identity The resulting infection was fatal and associated with immunological disorders at the time of transmission: in one case sepsis and in the other two cases immunosuppression. In a further asymptomatic case of proven transmission from the early window phase donation passively administered anti-HBs could not prevent spread of wildtype HBV but antiviral treatment lead to resolution. Surprisingly the typical acute hepatitis B was not observed in a single one of the 26 cases of assumed or proven transmission.

Published
2007

40. Quantitative Detection of Hepatitis B Virus DNA in Two International Reference Plasma Preparations

Author

Heermann, Klaus-Hinrich, Gerlich, Wolfram H., Chudy, Michael, Schaefer, Stephan, and Thomssen, Reiner

Abstract

ABSTRACTQuantitative detection of hepatitis B virus (HBV) in serum or plasma is of significance for monitoring of therapy and establishment of the prognosis of the disease, as well as for infectivity assessment and quality control of the diagnosis. Unfortunately, various commercially available test kits for HBV DNA yielded conflicting quantitative results, with differences of up to a factor of 120. The Eurohep Pathobiology Group has established two reference samples of plasma from HBV carriers and determined as accurately as possible the number of HBV DNA molecules in these samples. Plasma donations from two single highly viremic carriers of HBV genotype A (HBV surface antigen subtype adw2) and genotype D (ayw2/3), respectively, were collected, and coded dilutions of these samples were analyzed by members of the Eurohep Pathobiology Group. Quantitative results from the seven laboratories reporting consistent results were initially divergent. Limiting dilution and nested PCR assays suffered from incomplete DNA extraction. Hybridization assays used inaccurately quantitated cloned DNA as a reference. Two hybridization assays could not be calibrated directly with cloned HBV DNA, because virion-derived DNA reacted much less efficiently. After identification and elimination of these problems, limiting-dilution assays from three laboratories and hybridization assays from two producers generated consistent and concordant results: 2.7 × 109HBV DNA molecules/ml (range, 2.1 × 109to 3.4 × 109HBV DNA molecules/ml) in the plasma from the carrier of genotype A and 2.6 × 109HBV DNA molecules/ml (range, 2.1 × 109to 3.0 × 109HBV DNA molecules/ml in the plasma from the carrier of genotype D. The two Eurohep reference plasma samples have already been used for the standardization of test kits and in quality control trials, and the plasma from the carrier of genotype A will probably be the basis of a World Health Organization reference sample.

Published
1999
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41. World Health Organization International Standard To Harmonize Assays for Detection of Mycoplasma DNA.

Author

Nübling, C. Micha, Baylis, Sally A., Hanschmann, Kay-Martin, Montag-Lessing, Thomas, Chudy, Michael, Kreß, Julia, Ulrych, Ursula, Czurda, Stefan, and Rosengarten, Renate

Subjects
*NUCLEIC acid amplification techniques, *MYCOPLASMA, *CELL culture, *MONOCLONAL antibodies, *PROTEINS
Abstract

Nucleic acid amplification technique (NAT)-based assays (referred to here as NAT assays) are increasingly used as an alternative to culture-based approaches for the detection of mycoplasma contamination of cell cultures. Assay features, like the limit of detection or quantification, vary widely between different mycoplasma NAT assays. Biological reference materials may be useful for harmonization of mycoplasma NAT assays. An international feasibility study included lyophilized preparations of four distantly related mycoplasma species (Acholeplasma laidlawii, Mycoplasma fermentans, M. orale, M. pneumoniae) at different concentrations which were analyzed by 21 laboratories using 26 NAT assays with a qualitative, semiquantitative, or quantitative design. An M. fermentans preparation was shown to decrease the interassay variation when used as a common reference material. The preparation was remanufactured and characterized in a comparability study, and its potency (in NAT-detectable units) across different NATs was determined. The World Health Organization (WHO) Expert Committee on Biological Standardization (ECBS) established this preparation to be the "1st World Health Organization international standard for mycoplasma DNA for nucleic acid amplification technique-based assays designed for generic mycoplasma detection" (WHO Tech Rep Ser 987:42, 2014) with a potency of 200,000 IU/ml. ThisWHOinternational standard is now available as a reference preparation for characterization of NAT assays, e.g., for determination of analytic sensitivity, for calibration of quantitative assays in a common unitage, and for defining regulatory requirements in the field of mycoplasma testing. [ABSTRACT FROM AUTHOR]

Published
2015
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