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Updated: Jun 3, 2025

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
HIV Replication Under High-Level Cabotegravir Is Associated with the Appearance of 3'-PPT Mutations, Circular DNA
Xierong Wei1, Jonathan T Lipscomb1, Ariana Santos Tino1,2
1Laboratory Branch, Division of HIV Prevention, National Center for HIV, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA.
Abstract:
The HIV integrase inhibitor, dolutegravir (DTG), in the absence of eliciting integrase (int) resistance, has been reported to select mutations in the virus 3'-polypurine tract (3'-PPT) adjacent to the 3'-LTR U3. An analog of DTG, cabotegravir (CAB), has a high genetic barrier to drug resistance and is used in formulations for treatment and long-acting pre-exposure prophylaxis. We examined whether mutations observed for DTG would emerge in vitro with CAB. HIV-1IIIB was cultured in paired experiments of continuous high (300 nM) CAB initiated 2 h or 24 h after infection. After eight months of CAB treatment, no int resistance was detected. Conversely, HIV RNA 3'-PPT mutants were detected within one month and were the majority virus by day 98. The appearance of 3'-PPT variants coincided with a rapid accumulation of HIV 1-LTR and 2-LTR circles. RNA amplification from the 3'-LTR TAR identified transcripts crossing 2-LTR circle junctions, which incorporated the adjacent U5 sequence identical to the 3'-PPT mutants. 3'-PPT variants were only identified in LTR circles and transcripts. Additionally, we found evidence of linear HIV and LTR circle recombination with human DNA at motifs homologous to 3'-PPT sequences. HIV persistence under CAB was associated with transcription and recombination of LTR circle sequences.
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