Enhancing the specificity of the COBAS AMPLICOR CT/NG test for Neisseria gonorrhoeae by retesting specimens with equivocal results.

The COBAS AMPLICOR CT/NG test for Neisseria gonorrhoeae cross-reacts with certain strains of nonpathogenic Neisseria species. In some strains, the target sequence is identical to that of N. gonorrhoeae, whereas other strains have a small number of mismatches within the regions recognized by the primers or probe used in the COBAS AMPLICOR NG test.

Performance characteristics of the COBAS AmpliScreen HIV-1 test, version 1.5, an assay designed for screening plasma mini-pools.

Background: The COBAS AmpliScreen HIV-1 test, version 1.5 (v1.5) (Roche Molecular Systems), is designed for screening pools composed of samples from 24 individual units of blood or plasma.

Performance characteristics of a quantitative, homogeneous TaqMan RT-PCR test for HCV RNA.

We developed a homogeneous format reverse transcription-polymerase chain reaction assay for quantitating hepatitis C virus (HCV) RNA based on the TaqMan principle, in which signal is generated by cleaving a target-specific probe during amplification. The test uses two probes, one specific for HCV and one specific for an internal control, containing fluorophores with different emission spectra. Titers are calculated in international units (IU)/ml by comparing the HCV signal generated by test samples to that generated by a set of external standards.

Ultrasensitive Quantitation of Human Immunodeficiency Virus Type 1 RNA in Plasma by the AMPLICOR and COBAS AMPLICOR HIV-1 MONITOR™ Tests.

The measurement of plasma human immunodeficiency virus type 1 (HIV-1) RNA levels has become an important tool for identifying individuals likely to benefit from antiretroviral therapy (1-7) as well as monitoring patients on therapy (8-14), and is now regarded as standard medical practice for managing the treatment of HIV-1-infected individuals (15-21). Three commercially available assays for measuring HIV-1 RNA levels are available. The firstgeneration AMPLICOR HIV-1 MONITOR™ Test, which uses reverse transcriptase-polymerase chain reaction (RT-PCR) technology, has a lower limit of quantitation of 400 copies/mL of plasma (22,23).

Improved version 2.0 qualitative and quantitative AMPLICOR reverse transcription-PCR tests for hepatitis C virus RNA: calibration to international units, enhanced genotype reactivity, and performance characteristics.

Version 2.0 qualitative and quantitative AMPLICOR reverse transcription-PCR tests for HCV were designed to improve on the performance of first version of the hepatitis C virus (HCV) tests. The new tests were calibrated in international units, the new commonly accepted standard unit of measurement for HCV RNA.