Ultrasensitive reverse transcription-PCR assay for quantitation of human immunodeficiency virus type 1 RNA in plasma.
With the recent introduction of combination therapy, human immunodeficiency virus type 1 (HIV-1) RNA levels in plasma have been dramatically reduced, frequently to below the limit of quantitation (400 copies/ml of plasma) of the AMPLICOR HIV-1 MONITOR Test (Roche Diagnostic Systems). To achieve enhanced sensitivity of the AMPLICOR HIV-1 MONITOR Test, a modified specimen preparation procedure that allows input of RNA from 10-fold more plasma per amplification reaction was developed. This "ultrasensitive" method allows the accurate quantitation of plasma HIV-1 RNA levels as low as 50 copies/ml. A precision study yielded average within-run and between-run coefficients of variation (CV) of 24.8 and 9.6%, respectively. A multicenter reproducibility study demonstrated that the laboratory-to-laboratory reproducibility of this assay is good, with an average CV of 32%. The linear range of this test is between 50 and 50,000 copies/ml of plasma. RNA concentrations measured by the ultrasensitive and standard HIV-1 MONITOR tests exhibited good agreement within the shared linear range of the two methods. The two measurements were within a factor of 2 for 91% of the specimens tested, with the concentration measured by the ultrasensitive method being only slightly lower (median, 22% lower). Preliminary studies suggest that this assay will prove to be useful for predicting the stability of viral suppression in patients whose RNA levels drop below 400 copies/ml in response to highly active antiretroviral therapy.
Sun
R
R
Roche Molecular Systems, Inc., Branchburg, New Jersey 08876, USA.
Ku
J
J
Jayakar
H
H
Kuo
J C
JC
Brambilla
D
D
Herman
S
S
Rosenstraus
M
M
Spadoro
J
J
D000163:Acquired Immunodeficiency Syndrome / Q000097:blood / Q000175:diagnosis*; D015658:HIV Infections / Q000097:blood / Q000175:diagnosis*; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007753:Laboratories / Q000592:standards; D015345:Oligonucleotide Probes; D011786:Quality Control; D012367:RNA, Viral / Q000097:blood*; D011933:Reagent Kits, Diagnostic; D012044:Regression Analysis; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000295:instrumentation / Q000379:methods*; D012680:Sensitivity and Specificity; D014481:United States
D015345:Oligonucleotide Probes; D012367:RNA, Viral; D011933:Reagent Kits, Diagnostic