Paucity of HIV DNA methylation in latently infected, resting CD4+ T cells from infected individuals receiving antiretroviral therapy

Abstract

Maintenance of HIV latency in vitro has been linked to methylation of HIV DNA. However, examinations of the degree of methylation of HIV DNA in the latently infected, resting CD4(+) T cells of infected individuals receiving antiretroviral therapy have been limited. Here, we show that methylation of the HIV 5' long terminal repeat (LTR) in the latent viral reservoir of HIV-infected aviremic individuals receiving therapy is rare, suggesting that other mechanisms are likely involved in the persistence of viral latency.

Fig 1

Level of HIV DNA methylation in latently infected, resting CD4⁺ T cells of infected individuals receiving ART and Jurkat cell lines. (A) Scheme of the HIV genome detailing where CpG methylation (mCpG) was analyzed within the 5′ LTR and env regions. The circles depict the approximate distribution of CpG dinucleotides, and the arrows show the positions of primers used for amplification/sequencing. (B) Levels of CpG methylation in the bisulfite-treated HIV 5′ LTR of resting CD4⁺ T cells isolated from the study subjects. (C) Examination of CpG methylation in the HIV 5′ LTR of Jurkat cell lines (H12 and 2D12). (D) Levels of CpG methylation in the HIV env region of resting CD4⁺ T cells isolated from the study subjects. Open and closed circles represent nonmethylated and methylated CpG residues, respectively. Each line of circles represents one copy of the HIV genome.