6800 system

Primary vials were initially processed by the p 480 v2 (with software 2.1.1) instrument, that performed spin-mixing, cap removal, barcode alignment and transfer of 2-ml sample aliquots to secondary vials, and recapping with the original primary vial cap.
The secondary vials were then manually transferred to the cobas 6800 system, a fully automated unit that provides full sample preparation and HPV detection without further intervention by the operator.
Both cobas HPV real-time PCR assays detect the same 14 types of HPV, use the same primers and probes, and provide partial genotyping for HPV16 and HPV18. The two assays do however differ in their Thermal Cycling (CT) profile (the cobas 6800/8800 runs a universal thermal cycling profile to allow for mixed batching of different PCR tests), as well as in the elution sample volume amplified (50 μl on 6800/8800 vs 150 μl on 4800 out of a 400 μl aliquot of extracted nucleic acids). Both HPV assays were performed according to the manufacturer’s instructions. Each plate, besides the 2 assay’s controls, contained 92 clinical specimens and 2 additional samples (selected from 10 internal and 5 external quality controls, and 2 clinical samples previously found to be invalid by the cobas 4800 HPV test).

The cobas EBV test was performed on either a cobas 6800 System or a cobas 8800 System (13 ). As these systems are fully automated molecular analyzers, all steps, including primary sample handling, DNA extraction, and PCR amplification, were performed in the same system without further manual intervention. The comparator assay, namely, the CE-IVD-approved (but not FDA-cleared) Abbott RealTime EBV assay, was performed on an m2000 RealTime System (m2000sp instrument for DNA extraction and 2000rt for PCR amplification), according to the manufacturer’s instructions (14 ).