Plasma viremia titration and RNA quantitation in ICD-p24 negative HIV type-1-infected patients.
Quantitative culture of human immunodeficiency virus (HIV) was performed on 202 plasma samples obtained from asymptomatic and early symptomatic HIV-1 infected patients (mean CD4+ count: 186/mm3) before antiretroviral therapy was started. HIV could be isolated from 84% of the plasma samples (titers ranging from 10(0) to 10(2.75) TCID50/ml). Immune complex dissociated p24 antigen (ICD-p24) was detected in 66% of the samples. Only 23 samples (11%) were negative for both ICD-p24 as well as HIV culture. Discordant results were obtained in 55 samples, and 45 samples negative for ICD-p24 were positive for HIV culture. A significant proportion (42%) of patients that were negative for ICD-p24 belonged to a very advanced group with very low CD4+ cell count. However, almost 90% of these ICD-p24 negative samples were positive for HIV plasma viremia, stressing the value of this virological marker in patients with low CD4+ cell count and without any detectable ICD-p24 antigenemia. HIV-1 RNA was detected in all ICD-p24 negative plasma samples tested by the branched DNA (bDNA) assay. A very good correlation was found between high RNA copy number and HIV plasma isolation in samples obtained from patients with low CD4+ cell count, suggesting that HIV-1 RNA quantitation may also reflect viral infectivity of plasma.
Ercoli
L
L
Department of Public Health and Cellular Biology, University Tor Vergata, Rome, Italy.
Sarmati
L
L
el-Sawaf
G
G
Cochi
S
S
Lanti
T
T
Iudicone
P
P
Guglielmetti
M
M
Giannini
G
G
Galluzzo
C
C
Tomino
C
C
D000936:Antigen-Antibody Complex / Q000097:blood; D000956:Antigens, Viral / Q000097:blood; D018791:CD4 Lymphocyte Count; D016655:HIV Core Protein p24 / Q000097:blood*; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D012367:RNA, Viral / Q000097:blood*; D014766:Viremia / Q000821:virology*
D000936:Antigen-Antibody Complex; D000956:Antigens, Viral; D016655:HIV Core Protein p24; D012367:RNA, Viral