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Proficiency Testing of In-House Developed HIV-1 NAT for Blood Screening Michael Chudy, Paul-Ehrlich-Institut Division of Virology, Section of Molecular Pathology Langen, Germany; Email: chumi@pei.de. SoGAT XVII/Paris, 2004. PEI.
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Proficiency Testingof In-House Developed HIV-1 NAT for Blood Screening Michael Chudy, Paul-Ehrlich-Institut Division of Virology, Section of Molecular Pathology Langen, Germany; Email: chumi@pei.de SoGAT XVII/Paris, 2004
PEI German Regulations for Blood Components and FFP: Implementation of HIV-1 NAT • BAnz. [Fed. Gazette] No 90, 9506; 05/16/2001 • detection limit of HIV-1 RNA: 10,000 IU/ml for single donation • prospective implementation 01/01/2002 • 08/27/2001: PEI announcement • HIV-1 subtypes: M group • PEI collaborative study of in-house NAT assays for detection of HIV-1 and HCV RNA;participation on voluntary basis (10/01/2001) • HIV-1 NAT implementation postponed
PEI Collaborative Study: In-house NAT Assays
PEI Collaborative Study 2001: Conclusions • HCV NAT (in-house): • homogeneous results (sensitivity, specificity, and proficiency) • no differences between SD- and MP-testing • HIV-1 NAT (in-house): • results less homogeneous • further improvements and validation • regular proficiency studies for in-house NAT assays organised by PEI • acceptance: successful participation
PEI German Regulations for Blood Components and FFP: Implementation of HIV-1 NAT • BAnz. [Fed. Gazette] No 103, 12269; 06/05/2003 • implementation 05/01/2004 • validation of in-house assays • acceptance of in-house assays: successful participation in PEI proficiency study
PEI Proficiency Study for In-house HIV-1 NAT Assays: : Objective Evaluation of in-house NAT assays for detection of HIV-1 in blood donations: • analytical sensitivity • subtype sensitivity • specificity • proficiency
PEI Proficiency Study for In-house HIV-1 NAT Assays: Study Design • Focus on the detection limit: • 10,000 IU HIV1-RNA/ml single donation • Materials • Reference preparations (WHO: 31,600, 10,000 2x, 3,160 IU/ml/PEI: 10,000 IU/ml) • HIV-1 subtypes (A, C, CRF_AE, G, H; each 10,000 IU/ml) • NHP pool (2x) • Simulation of the pool size (volume, dilution) • Lab and sample encoding • Samples frozen at -80°C/shipment on dry ice • Results: reactive/non-reactive (data sheet)
PEI Proficiency Study for In-house HIV-1 NAT Assays: Participants Overall 30 participants • 29 labs: blood screening; 2 labs only pooling/1 lab: manufacturer of plasma prod. • SD 1x; MP-8 1x; MP-10 3x; MP-15 2x, MP-20 4x, MP-24 2x, MP-40 1x, MP-48 5x; and MP-96 11 x • 7 labs with virus enrichment • NA extraction: 14 labs Qiagen/5 labs Roche/4 labs NucliSens/5 labs other • 23 real-time PCR (20x TaqMan/3x LC Hybr.) • 2x CA HIV-1 Monitor/3x RT-PCR +Gene Scanning
PEI Proficiency Study for In-house HIV-1 NAT Assays (2003): Conclusions • Results more homogeneous compared to the results of the study in 2001 • No differences in respect with the used pool size • Due to the test results, 2 test labs switched to commercial assays • Assessment of in-house assays: validation studies and successful participation in proficiency study • Conclusion: In-house assays are suitable for blood screening • CE-marking of in-house assays: open question