Replication-competent HIV strains infect HIV controllers despite undetectable viremia (ANRS EP36 study).

The replicative potential of HIV-1 strains in a well-characterized group of eight HIV controllers was investigated. Replication-competent viruses were detected in CD4 T-cell co-culture supernatants from all HIV controllers. The phylogenetic analysis of C2V4 suggested viral evolution or co-infection or superinfection in two out of the four patients analysed. The vif and vpr genes were normal. Infection with HIV-1 variants with attenuated replicative capacity cannot be a general factor accounting for undetectable viraemia in HIV controllers.

Prognostic impact of sleep-disordered breathing and its treatment with nocturnal ventilation for chronic heart failure.

AIMS: To determine whether severity patterns or nocturnal ventilation to treat sleep-disordered breathing (SDB) during chronic heart failure (CHF) is associated with adverse outcomes. Although SDB is frequent during CHF, the relationships between SDB and CHF outcomes are unknown. METHODS AND RESULTS: A total of 384 CHF patients (82% men, mean age 59 ± 13 years) with a left ventricular ejection fraction (LVEF) of ≤45% (mean LVEF 29 ± 9%) were assessed by polygraphy in our clinic between 2001 and 2009. Nocturnal ventilation was started according to the severity of SDB. Combined endpoints were death, heart transplant, and implant of a ventricular assist device. The prevalence of obstructive sleep apnoea (OSA), central sleep apnoea (CSA), and Cheyne-Stokes respiration (CSR) was 62, 26, and 29%, respectively. A primary endpoint occurred in 31%. Mean follow-up for survivors was 47 ± 25 months. Those with moderate [apnoea-hypopnoea index (AHI) ≤5-20/h] and severe SDB (AHI ≥20/h), and OSA and CSA, had poor prognoses compared with patients without SDB (P = 0.036, P = 0.003, respectively). A total of 31% of SDB patients were treated with nocturnal ventilation. Treated SDB had a better outcome than untreated severe SDB after adjustment for confounding factors [P = 0.031; hazard ratio (HR) 0.56; 95% confidence interval (CI) 0.33-0.95]. Subgroup analysis that included only OSA showed a similar result after adjustment (P = 0.017; HR 0.40; 95% CI 0.19-0.95). CONCLUSIONS: In CHF, SDB is associated with a poor prognosis whatever the SDB pattern, and nocturnal ventilation is associated with a better outcome.

CD4⁺ recent thymic emigrants are infected by HIV in vivo, implication for pathogenesis.

OBJECTIVE: The contribution of naive CD4⁺ T cells to the pool of HIV-infected cells remains poorly described. This study aimed at evaluating HIV infection in naive T-cell subsets in viremic and HAART-treated patients, together with various parameters implicated in naive T-cell homeostasis, in order to better understand infection in these subsets. DESIGN AND METHODS: HIV provirus was quantified in various FACS-sorted CD4/CD8 T-cell subsets [recent thymic emigrants (RTEs), non-RTE naives and memory T cells] purified from peripheral blood cells of untreated viremic and HAART-treated aviremic HIV-infected patients. HIV proviral DNA was quantified using a highly sensitive real-time PCR assay allowing detection of one HIV copy in 105 cells. Intrathymic precursor T-cell proliferation and circulating T-cell cycling were, respectively, evaluated through measurement of the sj/ßTREC ratio (signal joint T-Cell Receptor Excision Circle frequency divided by DßJßTREC frequency) and Ki-67 expression. Plasma interleukin (IL)-7 concentrations were measured by ELISA. RESULTS: RTEs and non-RTEs were equally HIV infected. Altogether, naive CD4⁺ T cells represented 0.24%-60% of the infected cells. In contrast, HIV DNA was undetectable in naive CD8⁺ T cells. RTE infection rate directly correlated with IL-7 plasma levels (r = 0.607, P = 0.0035) but was independent from plasma viral load, peripheral T-cell cycling and intrathymic precursor T-cell proliferation. CONCLUSION: We demonstrated that RTEs are effectively HIV infected. The similar infection rate observed in RTEs and other naive T cells, its relationship with plasma IL-7 levels, together with the lack of correlation between RTE infection and either thymic or peripheral proliferation, strongly suggests that RTE infection occurs either late during thymopoiesis or early on during their extrathymic maturation.

Synergistic activation of HIV-1 expression by deacetylase inhibitors and prostratin: implications for treatment of latent infection.

The persistence of transcriptionally silent but replication-competent HIV-1 reservoirs in Highly Active Anti-Retroviral Therapy (HAART)-treated infected individuals, represents a major hurdle to virus eradication. Activation of HIV-1 gene expression in these cells together with an efficient HAART has been proposed as an adjuvant therapy aimed at decreasing the pool of latent viral reservoirs. Using the latently-infected U1 monocytic cell line and latently-infected J-Lat T-cell clones, we here demonstrated a strong synergistic activation of HIV-1 production by clinically used histone deacetylase inhibitors (HDACIs) combined with prostratin, a non-tumor-promoting nuclear factor (NF)- kappaB inducer. In J-Lat cells, we showed that this synergism was due, at least partially, to the synergistic recruitment of unresponsive cells into the expressing cell population. A combination of prostratin+HDACI synergistically activated the 5' Long Terminal Repeat (5'LTR) from HIV-1 Major group subtypes representing the most prevalent viral genetic forms, as shown by transient transfection reporter assays. Mechanistically, HDACIs increased prostratin-induced DNA-binding activity of nuclear NF-kappaB and degradation of cytoplasmic NF-kappaB inhibitor, IkappaBalpha . Moreover, the combined treatment prostratin+HDACI caused a more pronounced nucleosomal remodeling in the U1 viral promoter region than the treatments with the compounds alone. This more pronounced remodeling correlated with a synergistic reactivation of HIV-1 transcription following the combined treatment prostratin+HDACI, as demonstrated by measuring recruitment of RNA polymerase II to the 5'LTR and both initiated and elongated transcripts. The physiological relevance of the prostratin+HDACI synergism was shown in CD8(+)-depleted peripheral blood mononuclear cells from HAART-treated patients with undetectable viral load. Moreover, this combined treatment reactivated viral replication in resting CD4(+) T cells isolated from similar patients. Our results suggest that combinations of different kinds of proviral activators may have important implications for reducing the size of latent HIV-1 reservoirs in HAART-treated patients.

Prolonged valproic acid treatment does not reduce the size of latent HIV reservoir.

OBJECTIVE: To investigate the impact of prolonged valproic acid treatment on the HIV reservoir in patients on highly active antiretroviral therapy. DESIGN: In a single-center pilot study, the size of the HIV reservoir of 11 patients receiving valproic acid for seizures for more than 2 years was compared with 13 matched patients. In addition, the outcome of patients receiving valproic acid in the French clinical trials of scheduled treatment interruption was recorded. METHODS: Total and integrated HIV-1 DNA in, respectively, peripheral blood mononuclear cells and CD4 T cells of the patients were quantified by real-time PCR methods. The frequency of CD4 T cells carrying replication-competent virus was estimated by a quantitative limiting-dilution assay in which virus growth was detected by RT-PCR in culture supernatants of activated CD4 T cells. Clinical charts of the patients included in scheduled treatment interruption trials receiving valproic acid were reviewed. RESULTS: Total and integrated HIV DNA were logarithmically more abundant than cells carrying replication-competent virus, but there was no significant difference in these three parameters between the two groups of matched patients. Three patients receiving valproic acid were included in scheduled treatment interruption trials. The rebound of viral replication was similar to that of the other patients of the trials. CONCLUSION: Long-term valproic acid therapy seems to be insufficient to reduce the size of the HIV-1 reservoir.