Usefulness of proviral DNA of human immunodeficiency virus type 1 in AIDS treatment decisions
(2012)
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- Authors
- Supervisors
- Goubau, Patrick
- Abstract
- (en) 1. Introduction: The project aims to establish the value of the quantification and characterization of the HIV-1 provirus. The assumption was that treatment that reduces the proviral load and the emergence of resistance has an impact on the reservoirs, thus on long-term effectiveness. 2. Development of the HIV-1 provirus DNA quantification The first objective of the project was to develop a real-time PCR assay to quantify the HIV-1 provirus present in subpopulations of circulating leukocytes, the CD4+ cells in comparison to a reference gene, in this case the beta-globin gene. The assay was also applied to a group of 15 patients undergoing a structured treatment interruption (STI) of at least 2 years. After interruption of treatment, 7 of 15 patients had a plasma viral load <3.3 log copies / ml and 3 had an undetectable viral load. All these 7 patients had a proviral load <2.5 log copies/106 CD4+ cells, including 4 with undetectable proviral load (<5 DNA copies / PCR). Eight patients had a viral load ranging from 3.9 to 4.7 log copies / ml, none of them had undetectable proviral load while 5 had a proviral load> 2.5 DNA copies / 106 CD4 + cells. 3. Follow up of treated patients 3.1 Patients Between May 2002 and July 2007, 69 patients who had not yet received antiretroviral treatment were included. Thirty-two patients received a combination of 2 NRTIs+1 PI, 12 patients received 2 NRTIs+1 NNRTI and 25 patients remained naive. Fifty-eight percent of patients were Europeans and 42% from outside Europe, mainly from Central Africa. Thirty-nine percent of HIV-1 sequences were subtype B. 3.2 Evolution of the proviral load HIV-1 proviral DNA was successfully amplified for 28 patients in the PI group, 12 patients in the NNRTI group and 14 patients who remained naïve. The patients were followed for a mean of 29 months. No difference in mean changes in proviral load between the 3 groups of patients was observed while mean changes in CD4+ cell count were statistically different between the treated groups on the one hand and the naïve patients on the other hand. 3.3 Analysis of proviral DNA sequences compared to the viral RNA The virus was successfully sequenced for 63 of the 69 persons selected, in both plasma and cells. The results showed that before treatment, 90 and 66% of detected mutations were respectively present in CD4 cells and plasma. We detected seven key mutations, 4 of them (M184M / V, M184M / I K103K / N M46M / I) were only found in cells. In 40 followed patients, the mutations detected at the naive stage remained present for at least 1 year after initiation of treatment. New key mutations emerged in the CD4 (M184I, M184M / I and Y188Y / H) during treatment. 4. Conclusion: Although the present study has certain limitations, obviously the small number of patients and the heterogeneity of the study population, some interesting findings can be seen at least as directions for further research. In terms of proviral load, this work did not show a higher impact of certain regimens associating RTIs with or without PIs on the HIV-1 proviral load. The variations were not statistically different between treated and untreated patients, while the effect of treatment on plasma viral load and CD4+ cell count was obvious. However, the use of the HIV-1 proviral DNA load as a reflection of reservoirs is gaining a new interest in the assessment of new treatment strategies to eradicate HIV infection. In terms of proviral nucleotide sequencing, a significantly higher number of mutations was detected in proviral DNA than in plasma RNA, and these mutations persisted for at least 1 year, regardless of the type of combination therapy. Four new mutations were detected and these included three in the provirus. The DNA analysis of HIV-1 might be useful in chronic infections in which wild type virus might overgrow any resistant HIV-1 variant or during simplification of treatment in patients with undetectable viraemia, when treatment needs to be modified because of toxicity or intolerance.
- Affiliations
Citations
Kabamba-Mukadi, B. (2012). Usefulness of proviral DNA of human immunodeficiency virus type 1 in AIDS treatment decisions. https://hdl.handle.net/2078.5/161313