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Updated: Jun 6, 2026
14:23
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
Reduced replication capacity of NL4-3 recombinant viruses encoding reverse transcriptase-integrase sequences from
Zabrina L Brumme1, Chun Li, Toshiyuki Miura
1Faculty of Health Sciences, Simon Fraser University, Burnaby, BC, Canada.
Journal of Acquired Immune Deficiency Syndromes (1999)
|December 3, 2010
Summary
Human leukocyte antigen (HLA) immune pressure on HIV-1 Pol compromises viral function in elite controllers. This viral attenuation may contribute to controlling viremia, offering insights for new therapies.
Area of Science:
- Virology
- Immunology
- Molecular Biology
Background:
- Identifying human leukocyte antigen (HLA) class I-associated determinants of HIV-1 elite control is crucial for developing novel therapeutics and vaccines.
- Previous studies indicated reduced replication capacity in controller-derived viruses, suggesting fitness costs of HLA-associated escape mutations in Gag.
- This research investigates potential functional defects in the Pol proteins of elite controllers.
Purpose of the Study:
- To determine if HIV-1 Pol proteins from elite controllers exhibit functional impairments.
- To assess the impact of HLA-associated escape mutations in Pol on viral replication capacity.
Main Methods:
- Constructed recombinant NL4-3 viruses using reverse transcriptase-integrase sequences from 58 elite controllers and 50 untreated chronic progressors.
- Measured viral replication capacity in vitro using a green fluorescent protein (GFP) reporter T-cell assay.
- Analyzed viral sequences for drug resistance and HLA-associated polymorphisms.
Main Results:
- Controller-derived viruses demonstrated significantly lower replication capacity than progressor-derived viruses (P < 0.0001).
- Attenuated viruses were most pronounced in controllers expressing HLA-B*57 or B*51.
- An inverse correlation between HLA-B*57-associated escape mutations in reverse transcriptase-integrase and replication capacity was significant in progressors (R = -0.89; P = 0.003) and trended in controllers (R = -0.36; P = 0.08).
Conclusions:
- HIV-1 Pol function appears compromised in elite controllers.
- HLA-associated immune pressure on Pol may contribute to viral attenuation and control of viremia, similar to Gag.
- Findings suggest a role for Pol fitness defects in HIV-1 elite control.
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