Detection of HIV-1 RNA in plasma and serum samples using the NASBA amplification system compared to RNA-PCR.
The presence of HIV-1 RNA in the plasma and serum of European and African patients was monitored using RNA-polymerase chain reaction (RNA-PCR) and the new isothermal NASBA nucleic acid amplification system encompassing a gel-based detection assay (ELGA). Identical RNA extraction procedures, provided by the NASBA amplification system, were used for both methods. The detection limit for HIV-1 RNA, measured on a 10-fold dilution series of spiked HIVIIIB in negative plasma, was about 0.05 CCID50 per test for both methods. Both NASBA and RNA-PCR were more sensitive than a p24 assay for the detection of circulating HIV-1 virus in blood: 17 of the 34 (50%) p24 antigen-tested seropositives were p24-positive while 32 (94%) were positive by NASBA and 30 (88%) by RNA-PCR. Among the 45 seropositives, 34 of which were tested for p24 antigen, 43 (96%) were positive by NASBA and 41 (91%) by RNA-PCR. Almost all seropositives had a detectable viral load in 100 microliters plasma. Lower viral loads were only encountered in some healthy seropositives with a higher CD4 count. There was no cross-reactivity with HIV-2 or HIV-I with both the RNA-PCR and NASBA. The extraction method used permitted the detection of HIV-1 RNA equally well in serum and in plasma with heparin or EDTA.
Vandamme
A M
AM
Rega Institute for Medical Research, Katholieke Universiteit Leuven, Belgium.
Van Dooren
S
S
Kok
W
W
Goubau
P
P
Fransen
K
K
Kievits
T
T
Schmit
J C
JC
De Clercq
E
E
Desmyter
J
J
D000349:Africa / Q000208:ethnology; D000465:Algorithms; D001483:Base Sequence; D002460:Cell Line; D003429:Cross Reactions; D017931:DNA Primers; D005060:Europe; D015750:Genes, gag; D016655:HIV Core Protein p24 / Q000097:blood; D006679:HIV Seropositivity / Q000175:diagnosis*; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008969:Molecular Sequence Data; D021141:Nucleic Acid Amplification Techniques; D016133:Polymerase Chain Reaction / Q000379:methods; D012367:RNA, Viral / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D017931:DNA Primers; D016655:HIV Core Protein p24; D012367:RNA, Viral