title: Lack of longitudinal intrapatient correlation between p24 antigenemia and levels of human immunodeficiency virus (HIV) type 1 RNA in patients with chronic hiv infection during structured treatment interruptions.
abstract: Structured treatment interruptions (STIs) have been proposed as a potential treatment strategy during human immunodeficiency virus type 1 (HIV-1) antiretroviral therapy. This still-experimental intervention requires a close monitoring of patients' plasma viremia and CD4(+)-T-cell counts during the treatment interruption phase. By using signal amplification of a heat-dissociated p24 antigen (p24Ag) assay, we compared p24Ag levels with levels of HIV RNA in plasma. One hundred seventy-four plasma samples were obtained from 51 chronically HIV-infected patients: 117 from patients who underwent STIs and 57 from patients who did not. Partial immune complex dissociation and clearance of those complexes by the erythrocytes were also investigated. A significant association between the two assays was observed (beta = 0.23, 95% confidence interval = 0.18, 0.28; P < 0.0001), but the association was smaller in the subset of samples from patients undergoing STIs. Moreover, discordant results and lack of longitudinal intrapatient correlation between levels of p24Ag and HIV-1 RNA were higher in this group. Incomplete immune complex dissociation and binding of those complexes to erythrocytes could be contributing factors involved in the diminished detection of p24Ag. Therefore, signal amplification of a heat-dissociated p24Ag had a positive association with current HIV RNA assays in a population-based analysis. However, it might not be sensitive enough to monitor longitudinal intrapatient viremia during STIs in patients with high CD4(+)-T-cell counts potentially due to the production of high-affinity anti-p24 antibodies and clearance of immune complexes by erythrocytes.
authors.affiliation: IrsiCaixa Foundation, Hospital Germans Trias i Pujol, Universitat Autonoma de Barcelona, Badalona, Spain.
authors.forename: Julia G
authors.initials: JG
authors.lastname: Prado
authors.forename: Ayumi
authors.initials: A
authors.lastname: Shintani
authors.forename: Margarita
authors.initials: M
authors.lastname: Bofill
authors.forename: Bonaventura
authors.initials: B
authors.lastname: Clotet
authors.forename: Lidia
authors.initials: L
authors.lastname: Ruiz
authors.forename: Javier
authors.initials: J
authors.lastname: Martinez-Picado
mesh_terms: D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D018791:CD4 Lymphocyte Count; D002908:Chronic Disease; D004334:Drug Administration Schedule; D016655:HIV Core Protein p24 / Q000097:blood*; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D006801:Humans; D012367:RNA, Viral / Q000097:blood*; D019562:Viral Load; D014766:Viremia / Q000188:drug therapy / Q000821:virology
chemical_list: D019380:Anti-HIV Agents; D016655:HIV Core Protein p24; D012367:RNA, Viral