Macioszek, J., Martinez, A., Tidd, J., Binder, A., Coffman, B., Sun, G., Truog, B., Boyd, R., Hoover, B., Lidgard, G., Shimei, T., Webb, M., Giachetti, C., McDonough, S., Mimms, L.T., Clark, S., Dahlen, T., and Frenette, D.
Background: The Chiron Procleix HIV-1/HCV Assay is a qualitative nucleic acid assay system for the detection of HIV-1 and HCV virus RNA in human plasma. The TIGRIS analyzer is under development as an integrated nucleic acid testing system, which fully automates all steps necessary to perform the Chiron Procleix HIV-1/HCV Assay, from sample processing through amplification and detection. Features such as specimen barcode reading, compatibility with a wide range of sample tubes, automated worklist creation, a Reagent Dispense Verification system and high throughput make the Tigris system suitable for medium and high volume screening of blood and plasma donations. Methods: Performance of the Procleix HIV-1/HCV Assay has been tested on the TIGRIS system on multiple instruments over a period of three months using sensitivity panels. Results: The assay sensitivity on the TIGRIS instrument was 99.5% (2349/2360) for 100 c/ml HIV-1 and 98.8% (2334/2362) for 30 c/ml HIV-1. For HCV virus detection, assay sensitivity was 99.9% (2356/2358) and 98.2% (2284/2325) at 100 c/ml and 30 c/ml, respectively. Initial reactive rate with a negative panel was 0.18% (4/2258) and Internal Control failure rate was 0.24% (32/13,340). The instrument throughput is greater than 400 tests in 8 hours. No false positive results were obtained when negative samples were interspersed in the same worklist with high positive HIV-1 samples containing 10[sup 9] c/ml. A 100% positivity rate for HIV-1 and HCV at 100 c/ml was obtained when sensitivity panels were spiked with putative interfering substances at the following concentrations: bilirubin at 200 mg/L (20 times normal level), hemoglobin at 5 g/L (500 times normal level), protein at 187.5 g/L (2.5 times normal level) and lipids at 2752 mg/dl (15 times normal level). The Reagent Dispense Verification system was shown to be effective in detection of inaccurate reagent addition when the instrument was tested under induced faulty operational states. Conclusion: The Chiron Procleix HIV1/HCV Assay on the TIGRIS system meets performance requirements for screening of blood donations. [ABSTRACT FROM AUTHOR]