Cellular HIV-1 DNA Levels in Drug Sensitive Strains Are Equivalent to Those in Drug Resistant Strains in Newly-Diagnosed Patients in Europe

Victoria L Demetriou,Jean-Claude Schmidt,Itzchak Levy,Ioanna Kousiappa,Lidia Ruiz,Louise B Jørgensen,Leondios G Kostrikis,Jurgen Vercauteren,Claus Nielsen,Mario Poljak,Zehava Grossman,Dimitrios Paraskevis,Francois Roman,David A M C Van De Vijver,Bonaventura Clotet,Claudia Balotta,Kristel Van Laethem,Snjezana Z Lepej,Anne-Mieke Vandamme

doi:10.1371/journal.pone.0010976

Abstract

BackgroundHIV-1 genotypic drug resistance is an important threat to the success of antiretroviral therapy and transmitted resistance has reached 9% prevalence in Europe. Studies have demonstrated that HIV-1 DNA load in peripheral blood mononuclear cells (PBMC) have a predictive value for disease progression, independently of CD4 counts and plasma viral load.Methodology/Principal FindingsMolecular-beacon-based real-time PCR was used to measure HIV-1 second template switch (STS) DNA in PBMC in newly-diagnosed HIV-1 patients across Europe. These patients were representative for the HIV-1 epidemic in the participating countries and were carrying either drug-resistant or sensitive viral strains. The assay design was improved from a previous version to specifically detect M-group HIV-1 and human CCR5 alleles. The findings resulted in a median of 3.32 log10 HIV-1 copies/106 PBMC and demonstrated for the first time no correlation between cellular HIV-1 DNA load and transmitted drug-resistance. A weak association between cellular HIV-1 DNA levels with plasma viral RNA load and CD4+ T-cell counts was also reconfirmed. Co-receptor tropism for 91% of samples, whether or not they conferred resistance, was CCR5. A comparison of pol sequences derived from RNA and DNA, resulted in a high similarity between the two.Conclusions/SignificanceAn improved molecular-beacon-based real-time PCR assay is reported for the measurement of HIV-1 DNA in PBMC and has investigated the association between cellular HIV-1 DNA levels and transmitted resistance to antiretroviral therapy in newly-diagnosed patients from across Europe. The findings show no correlation between these two parameters, suggesting that transmitted resistance does not impact disease progression in HIV-1 infected individuals. The CCR5 co-receptor tropism predominance implies that both resistant and non-resistant strains behave similarly in early infection. Furthermore, a correlation found between RNA- and DNA-derived sequences in the pol region suggests that genotypic drug-resistance testing could be carried out on either template.

Highlights

The development of antiretroviral therapy to fight HIV-1 infection has lead to a significant decrease in mortality and morbidity among infected populations
In this study the association between cellular HIV-1 DNA load and transmitted drug resistance was examined for the first time, using an improved molecular beacon-based real-time PCR assay for quantification of HIV-1 second template switch (STS) DNA and human CCR5 alleles
The median cellular HIV-1 STS DNA load calculated in this study is 3.32 log10 copies per 106 peripheral blood mononuclear cells (PBMC)

Summary

Introduction

The development of antiretroviral therapy to fight HIV-1 infection has lead to a significant decrease in mortality and morbidity among infected populations. Integrated HIV-1 DNA in host genomic DNA acts as a latent reservoir and ensures viral persistence in spite of prolonged antiretroviral therapy [9,10,11,12,13,14,15]. This persistent cellular reservoir can reactivate itself and replenish viral infection, presenting itself as one of the current challenges for the control of HIV-1 infection progression [16,17,18]. Studies have demonstrated that HIV-1 DNA load in peripheral blood mononuclear cells (PBMC) have a predictive value for disease progression, independently of CD4 counts and plasma viral load

Methods

Results

Conclusion