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Effects of raltegravir on 2-long terminal repeat circle junctions in HIV type 1 viremic and aviremic patients.

ABSTRACT: Although 2-long terminal repeat (2-LTR) circles are only a fraction of the total viral DNA in infected cells, sequence analysis of 2-LTR circles reveals critical information regarding viral DNA synthesis and the nature of actively replicating virus. It was observed that a large proportion of the 2-LTR circular molecules in the peripheral blood mononuclear cell (PBMC) DNA of infected individuals are mutated at the circle junction. The integrase inhibitor raltegravir (RAL) blocks the strand transfer step of the integration of HIV-1; as a consequence of abortive integration a significant increase of episomal 2-LTR circles is observed. Moreover, it was demonstrated that in patients treated with highly active retroviral therapy (HAART) changes in 2-LTR concentration did not affect junction sequences and flanking regions of 2-LTR. Here we evaluated whether RAL therapy could have a differential impact on the 2-LTR circle junctional sequences in patients with different virological profiles at the time of starting RAL therapy. Sequence analysis indicates that RAL acts differently in the two populations.

SUBMITTER: Bona R

PROVIDER: S-EPMC3785805 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Effects of raltegravir on 2-long terminal repeat circle junctions in HIV type 1 viremic and aviremic patients.

Bona Roberta R Baroncelli Silvia S D'Ettorre Gabriella G Andreotti Mauro M Ceccarelli Giancarlo G Filati Piero P Leone Pasqualina P Blasi Maria M Michelini Zuleika Z Galluzzo Clementina Maria CM Mallano Alessandra A Vullo Vincenzo V Cara Andrea A

AIDS research and human retroviruses 20130724 10

Although 2-long terminal repeat (2-LTR) circles are only a fraction of the total viral DNA in infected cells, sequence analysis of 2-LTR circles reveals critical information regarding viral DNA synthesis and the nature of actively replicating virus. It was observed that a large proportion of the 2-LTR circular molecules in the peripheral blood mononuclear cell (PBMC) DNA of infected individuals are mutated at the circle junction. The integrase inhibitor raltegravir (RAL) blocks the strand transf ...[more]

PMID: 23802629

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Project description:ObjectivePrior hypothesis-driven studies identified immunophenotypic characteristics associated with the control of HIV replication without antiretroviral therapy (HIV controllers) as well as with the degree of CD4 T-cell recovery during ART. We hypothesized that an unbiased 'discovery-based' approach might identify novel immunologic characteristics of these phenotypes.DesignWe performed immunophenotyping on four 'aviremic' patient groups: HIV controllers (n = 98), antiretroviral-treated immunologic nonresponders (CD4 < 350; n = 59), antiretroviral-treated immunologic responders (CD4 > 350, n = 142), and as a control group HIV-negative adults (n = 43). We measured levels of T-cell maturation, activation, dysfunction, senescence, functionality, and proliferation.MethodsSupervised learning assessed the relative importance of immune parameters in predicting clinical phenotypes (controller, immunologic responder, or immunologic nonresponder). Unsupervised learning clustered immune parameters and examined if these clusters corresponded to clinical phenotypes.ResultsHIV controllers were characterized by high percentages of HIV-specific T-cell responses and decreased percentages of cells expressing human leukocytic antigen-antigen D related in naive, central memory, and effector T-cell subsets. Immunologic nonresponders were characterized by higher percentages of CD4 T cells that were TNFα+ or INFγ+, higher percentages of activated naive and central memory T cells, and higher percentages of cells expressing programmed cell death protein 1. Unsupervised learning found two distinct clusters of controllers and two distinct clusters of immunologic nonresponders, perhaps suggesting different mechanisms for the clinical outcomes.ConclusionOur discovery-based approach confirmed previously reported characteristics that distinguish aviremic individuals, but also identified novel immunologic phenotypes and distinct clinical subpopulations that should lead to more focused pathogenesis studies that might identify targets for novel therapeutic interventions.

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Dataset Information

Effects of raltegravir on 2-long terminal repeat circle junctions in HIV type 1 viremic and aviremic patients.

Publications

Effects of raltegravir on 2-long terminal repeat circle junctions in HIV type 1 viremic and aviremic patients.

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