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Updated: May 7, 2026
10:34
Measurement of In Vitro Integration Activity of HIV-1 Preintegration Complexes
Published on: February 22, 2017
An HIV-1 replication pathway utilizing reverse transcription products that fail to integrate
Benjamin Trinité1, Eric C Ohlson, Igor Voznesensky
1Department of Basic Science, New York University College of Dentistry, New York, New York, USA.
Journal of Virology
|September 20, 2013
Summary
Unintegrated HIV-1 DNA can produce new virus in resting CD4+ T cells, bypassing integration. This finding reveals a novel viral replication pathway and potential therapeutic target for HIV-1.
Area of Science:
- Virology
- Immunology
- Molecular Biology
Background:
- Integration is key for retroviral replication, but most HIV-1 DNA remains unintegrated.
- The role of unintegrated HIV-1 DNA in infection has been unclear, often considered a replicative dead end.
- Resting CD4+ T cells are HIV-1 targets, and cytokines can render them permissive to infection.
Purpose of the Study:
- To investigate the role of unintegrated HIV-1 DNA in viral replication.
- To explore de novo virus production from unintegrated viral DNA in resting CD4+ T cells.
- To understand the conditions and factors influencing gene expression and replication from unintegrated HIV-1 DNA.
Main Methods:
- Infection of cytokine-treated resting CD4+ T cells with HIV-1.
- Use of raltegravir or integrase-mutant HIV-1 to block integration.
- Analysis of de novo virus production following T cell activation.
- Investigation of HIV-1 Vpr's role in unintegrated DNA gene expression.
Main Results:
- Cytokine-treated resting CD4+ T cells infected with integration-defective HIV-1 produced new virus upon activation.
- A population of cells generated virus from unintegrated HIV-1 DNA even with integration-competent virus.
- Latent infection from unintegrated DNA persisted for weeks and could be reactivated.
- HIV-1 Vpr was crucial for gene expression and virus production from unintegrated DNA.
Conclusions:
- Unintegrated HIV-1 DNA can contribute to viral replication and persistence in resting CD4+ T cells.
- This pathway bypasses integration, potentially preserving viral genetic information.
- HIV-1 Vpr plays a critical role in enabling replication from unintegrated viral DNA.
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