34 research outputs found
Comparison of OnceâDaily versus TwiceâDaily Combination Antiretroviral Therapy in TreatmentâNaive Patients: Results of AIDS Clinical Trials Group (ACTG) A5073, a 48âWeek Randomized Controlled Trial
Dosing frequency is an important determinant of regimen effectiveness
Preâexisting Minority DrugâResistant HIVâ1 Variants, Adherence, and Risk of Antiretroviral Treatment Failure
The clinical relevance of detecting minority drug-resistant HIV-1 variants is uncertain
Levels of HIV-1 persistence on antiretroviral therapy are not associated with markers of inflammation or activation
Antiretroviral therapy (ART) reduces levels of HIV-1 and immune activation but both can persist despite clinically effective ART. The relationships among pre-ART and on-ART levels of HIV-1 and activation are incompletely understood, in part because prior studies have been small or cross-sectional. To address these limitations, we evaluated measures of HIV-1 persistence, inflammation, T cell activation and T cell cycling in a longitudinal cohort of 101 participants who initiated ART and had well-documented sustained suppression of plasma viremia for a median of 7 years. During the first 4 years following ART initiation, HIV-1 DNA declined by 15-fold (93%) whereas cell-associated HIV-1 RNA (CA-RNA) fell 525-fold (>99%). Thereafter, HIV-1 DNA levels continued to decline slowly (5% per year) with a half-life of 13 years. Participants who had higher HIV-1 DNA and CA-RNA before starting treatment had higher levels while on ART, despite suppression of plasma viremia for many years. Markers of inflammation and T cell activation were associated with plasma HIV-1 RNA levels before ART was initiated but there were no consistent associations between these markers and HIV-1 DNA or CA-RNA during long-term ART, suggesting that HIV-1 persistence is not driving or driven by inflammation or activation. Higher levels of inflammation, T cell activation and cycling before ART were associated with higher levels during ART, indicating that immunologic events that occurred well before ART initiation had long-lasting effects despite sustained virologic suppression. These findings should stimulate studies of viral and host factors that affect virologic, inflammatory and immunologic set points prior to ART initiation and should inform the design of strategies to reduce HIV-1 reservoirs and dampen immune activation that persists despite ART
T-cell responses targeting HIV Nef uniquely correlate with infected cell frequencies after long-term antiretroviral therapy
HIV-specific CD8+ T-cell responses limit viral replication in untreated infection. After the initiation of antiretroviral therapy (ART), these responses decay and the infected cell population that remains is commonly considered to be invisible to T-cells. We hypothesized that HIV antigen recognition may persist in ART-treated individuals due to low-level or episodic protein expression. We posited that if persistent recognition were occurring it would be preferentially directed against the early HIV gene products Nef, Tat, and Rev as compared to late gene products, such as Gag, Pol, and Env, which have higher barriers to expression. Using a primary cell model of latency, we observed that a Nef-specific CD8+ T-cell clone exhibited low-level recognition of infected cells prior to reactivation and robust recognition shortly thereafter. A Gag-specific CD8+ T-cell clone failed to recognized infected cells under these conditions, corresponding with a lack of detectable Gag expression. We measured HIV-specific T-cell responses in 96 individuals who had been suppressed on ART for a median of 7 years, and observed a significant, direct correlation between cell-associated HIV DNA levels and magnitudes of IFN-Îł-producing Nef/Tat/Rev-specific T-cell responses. This correlation was confirmed in an independent cohort (n = 18). Correlations were not detected between measures of HIV persistence and T-cell responses to other HIV antigens. The correlation with Nef/Tat/Rev-specific T-cells was attributable to Nef-specific responses, the breadth of which also correlated with HIV DNA levels. These results suggest that ongoing Nef expression in ART-treated individuals drives preferential maintenance and/or expansion of T-cells reactive to this protein, implying sensing of infected cells by the immune system. The direct correlation, however, suggests that recognition does not result in efficient elimination of infected cells. These results raise the possibility that enhancing the cytolytic activity of Nef-specific T-cells may lead to reductions in infected cell frequencies, even in the absence of therapeutic latency reversal
Mid-pregnancy sleep disturbances are not associated with mid-pregnancy maternal glycemia
Background: In pregnancy, epidemiological data have consistently shown strong associations between sleep quality and duration and maternal glycemia. However, other sleep disturbances such as difficulty falling asleep and staying asleep are common in pregnancy. They may contribute to impaired maternal glycemia through sympathetic nervous system activity, systemic inflammation, and hormonal pathways. However, there is little research examining associations between these specific sleep disturbances and maternal glycemia.
Objective: This study aimed to investigate the associations of sleep disturbances during mid-pregnancy and mid-pregnancy maternal glycemia and gestational diabetes subtypes.
Study design: This is a secondary data analysis of the Comparison of Two Screening Strategies for Gestational Diabetes trial. Participants (n = 828) self-reported the frequency of sleep disturbances (i.e., trouble falling asleep, trouble staying asleep, waking several times per night, and waking feeling tired or worn out) in mid-pregnancy. Gestational diabetes was diagnosed using either the International Associations of Diabetes and Pregnancy Study Groups or Carpenter-Coustan approach. We defined gestational diabetes subtypes based on the degree of insulin resistance and beta-cell dysfunction. We used multinomial logistic regression to examine associations of sleep disturbances with gestational diabetes status (i.e., normal, mild glycemic dysfunction, and gestational diabetes) and gestational diabetes subtypes (i.e., neither insulin resistance or beta-cell dysfunction, insulin resistance only, beta-cell dysfunction only, and insulin resistance and beta-cell dysfunction).
Results: A total of 665 participants (80%) had normal glycemia, 81 (10%) mild hyperglycemia, and 80 (10%) had gestational diabetes. Among participants with gestational diabetes, 62 (78%) had both insulin resistance and beta-cell dysfunction, 15 (19 %) had insulin resistance only, and 3 had beta-cell dysfunction only or neither insulin resistance nor beta-cell dysfunction. Sleep disturbance frequency was not associated with maternal glycemia or gestational diabetes subtypes.
Conclusions: Sleep disturbances in mid-pregnancy were not associated with maternal glycemia during mid-pregnancy. Future research should collect data on sleep disturbances at multiple time points in pregnancy and in combination with other sleep disturbances to determine whether sleep plays any role in maternal glycemic control
Comparison of Three Different FDA-Approved Plasma HIV-1 RNA Assay Platforms Confirms the Virologic Failure Endpoint of 200 Copies per Milliliter Despite Improved Assay Sensitivity
Discrepancies between HIV-1 RNA results assayed by different FDA-approved platforms have been reported. Plasma samples collected from 332 randomly selected clinical trial participants during the second year of antiretroviral treatment were assayed with three FDA-approved platforms: UltraSensitive Roche Amplicor Monitor, v1.5 (Monitor), the Abbott RealTime HIV-1 test on the m2000 system (Abbott), and the Roche TaqMan HIV-1 test, v2.0 (TaqMan). Samples from 61 additional participants with confirmed HIV-1 RNA levels of \u3e50 copies/ml during trial follow-up were also included. Endpoints were HIV-1 RNA quantification of â€50 copies/ml versus \u3e50 copies/ml at an individual-sample level (primary) and determination of confirmed virologic failure (VF) from longitudinal samples. A total of 389 participants had results obtained from all assays on at least one sample (median = 6). Proportions of results of \u3e50 copies/ml were 19% (Monitor), 22% (TaqMan), and 25% (Abbott). Despite indication of strong agreement (Cohen\u27s kappa, 0.76 to 0.82), Abbott was more likely to detect HIV-1 RNA levels of \u3e50 copies/ml than Monitor (matched-pair odds ratio [mOR] = 4.2; modified Obuchowski P \u3c 0.001) and TaqMan (mOR = 2.1; P \u3c 0.001); TaqMan was more likely than Monitor (mOR = 2.6; P \u3c 0.001). Despite strong agreement in classifying VF across assay comparisons (kappa, 0.75 to 0.92), at a 50-copies/ml threshold, differences in the probability of VF classification (in the same direction as primary) were apparent (all McNemar\u27s P \u3c 0.007). At a 200-copies/ml VF threshold, no differences between assays were apparent (all P \u3e 0.13). Despite strong agreement among assays, significant differences were observed with respect to detecting HIV-1 RNA levels of \u3e50 copies/ml and identifying VF at the 50-copies/ml threshold. This has important implications for the definition of VF in clinical trials and clinical practice
Recommended from our members
Lower pre-ART intra-participant HIV-1 <i>pol</i> diversity may not be associated with virologic failure in adults
<div><p>Background</p><p>Identifying pre-ART factors associated with the emergence of HIV-1 drug resistance is critical for optimizing strategies to prevent virologic failure. A previous study reported that lower pre-ART HIV-1 <i>pol</i> diversity was associated with higher risk of virologic failure in HIV-1-infected children. To investigate this association in adults, we measured HIV-1 diversity with deep sequencing in pre-ART samples from adults with well-characterized virologic outcomes in a study (A5142) of initial ART conducted by the AIDS Clinical Trials Group (ACTG).</p><p>Methods</p><p>We identified 22 cases in ACTG A5142 who experienced virologic failure with drug resistance mutations in RT and 44 matched controls who did not experience virologic failure. cDNA was synthesized from plasma HIV-1 RNA. Each cDNA molecule was tagged with a unique primer ID and RT codons 41â103 were amplified and deep sequenced. Sequences with the same tag were aligned and a consensus was generated to reduce PCR and sequencing errors. Diversity was calculated by measuring average pairwise distance (APD) of the consensus sequences. An exact conditional logistic regression model with percent APD as the risk factor estimated the odds ratio for VF and the corresponding 95% confidence interval.</p><p>Results</p><p>Consensus single-genome sequences and diversity estimates of <i>pol</i> were obtained for pre-ART samples from 21 cases and 42 controls. The median (IQR) pre-ART percent APD was 0.71 (0.31â1.13) in cases and 0.58 (0.32â0.94) in controls. A possible trend was found for higher diversity being associated with greater risk of virologic failure in adults (OR = 2.2 per one percent APD increase, 95% CI = [0.8, 7.2]; p = 0.15).</p><p>Conclusions</p><p>This study in adults suggests there is a positive association between higher pre-ART <i>pol</i> diversity and the risk of virologic failure in adults rather than an inverse relationship reported in children.</p></div
Percent Average Pairwise Distance (%APD) for each cut off.
<p>Percent Average Pairwise Distance (%APD) for each cut off.</p
Pre-ART participants characteristics used for matching.
<p>Pre-ART participants characteristics used for matching.</p