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A Restriction Enzyme Based Cloning Method to Assess the In vitro Replication Capacity of HIV-1 Subtype C Gag-MJ4 Chimeric Viruses
Published on: August 31, 2014
Plasma viral load threshold for sustaining intrahost HIV type 1 evolution.
Gonzalo Bello1, Concepción Casado, Virginia Sandonis
1Laboratorio de AIDS e Imunologia Molecular, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil.
AIDS Research and Human Retroviruses
|October 27, 2007
Summary
Persistent low plasma viremia below 80 copies/ml may halt human immunodeficiency virus type 1 (HIV-1) evolution. This finding suggests ultrasensitive assays can identify a threshold for containing HIV-1 genetic diversity.
Area of Science:
- Virology
- Immunology
- Genetics
Background:
- Long-term nonprogressors (LTNPs) naturally control human immunodeficiency virus type 1 (HIV-1) replication.
- Understanding the factors that prevent HIV-1 evolution in LTNPs is crucial for developing effective treatment strategies.
Purpose of the Study:
- To investigate whether natural suppression of plasma viremia below commercial assay detection limits (50-80 copies HIV-1 RNA/ml) can inhibit HIV-1 evolution.
- To assess the correlation between plasma viral load and intrahost HIV-1 genetic diversity in LTNPs.
Main Methods:
- Assessed HIV-1 quasispecies complexity in peripheral blood mononuclear cell (PBMC) DNA (env gene) at two time points.
- Analyzed plasma HIV-1 RNA viral loads in 14 LTNPs with varying degrees of viremia control.
Main Results:
- Viral evolution was observed in all patients with median plasma viral loads >100 copies/ml.
- Low-level viral evolution was detected in patients with intermittent viremia (>80 copies/ml).
- No significant evolution occurred in LTNPs with persistent viral suppression (<50-80 copies/ml).
- A significant positive correlation (p < 0.001) was found between viral evolution and plasma viral load.
Conclusions:
- Persistent plasma viremia below the detection limit of ultrasensitive assays may prevent intrahost HIV-1 evolution.
- The detection limit of ultrasensitive viremia assays could be a critical threshold for containing HIV-1 genetic diversity.
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