Related Experiment Video
Updated: May 11, 2026
10:34
Measurement of In Vitro Integration Activity of HIV-1 Preintegration Complexes
Published on: February 22, 2017
Multiple proviral integration events after virological synapse-mediated HIV-1 spread
Rebecca A Russell1, Nicola Martin, Ivonne Mitar
1The Sir William Dunn School of Pathology, The University of Oxford, South Parks Road, Oxford OX13RE, UK. rebecca.moore@path.ox.ac.uk
Virology
|June 1, 2013
Summary
Human immunodeficiency virus type 1 (HIV-1) cell-to-cell spread via virological synapses (VS) leads to efficient proviral integration and productive T cell infection. This process results in higher viral DNA and RNA production compared to cell-free infection.
Area of Science:
- Virology
- Immunology
- Cell Biology
Background:
- Human immunodeficiency virus type 1 (HIV-1) spreads between T cells through virological synapses (VS).
- The precise outcomes of HIV-1 transfer via VS on target cell infection are not fully understood.
Purpose of the Study:
- To investigate whether HIV-1 transfer through VS results in productive, high-multiplicity infection of target cells.
- To elucidate the efficiency of proviral integration and subsequent viral replication following cell-to-cell transmission.
Main Methods:
- Fluorescence in-situ hybridization (FISH) to visualize nuclear import of proviruses.
- Quantitative PCR (qPCR) to detect de novo viral DNA and RNA production.
- Comparison between cell-to-cell (VS-mediated) and cell-free infection systems.
Main Results:
- HIV-1 cell-to-cell spread via VS resulted in the nuclear import of multiple proviruses into target cells.
- Proviral integration efficiency was significantly higher in cell-to-cell spread compared to cell-free infection.
- De novo viral DNA and RNA production increased over time in target cells following VS-mediated transfer.
Conclusions:
- Efficient proviral integration occurs across virological synapses during HIV-1 cell-to-cell spread.
- Multiple integration events in target cells driven by VS transfer contribute to productive T cell infection.
- Cell-to-cell transmission via VS is a highly effective mechanism for establishing productive HIV-1 infection.
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