46 research outputs found
Brief Report: HIV Antibodies Decline During Antiretroviral Therapy but Remain Correlated With HIV DNA and HIV-Specific T-Cell Responses
Background: In people with HIV on antiretroviral therapy (ART), the relationship between HIV-specific immune responses and measures of HIV persistence is uncertain. Methods: We evaluated 101 individuals on suppressive ART in the AIDS Clinical Trials Group A5321 cohort. Cell-associated (CA) HIV DNA and RNA levels and HIV antibody concentrations and avidity to Env/p24 were measured longitudinally at years 1, 4, and 6-15 after ART initiation. Plasma HIV RNA by single copy assay and T-cell responses (IFN-ĂŽÂł ELISPOT) against multiple HIV antigens were measured at the last time point. Results: HIV antibody levels declined significantly with increasing time on ART (19%/year between year 1 and 4). HIV antibody levels correlated with T-cell responses to HIV Pol (r = 0.28, P = 0.014) and to Nef/Tat/Rev (r = 0.34; P = 0.002). HIV antibody and T-cell responses were positively associated with HIV DNA levels; for example, at the last time point (median 7 years on ART), r = 0.35 for antibody levels and HIV DNA (P < 0.001); r = 0.23 for Nef/Tat/Rev-specific T-cell responses and HIV DNA (P = 0.03). Neither antibody nor T-cell responses correlated with cell-associated HIV RNA or plasma RNA by single copy assay. Conclusions: In individuals on long-term ART, HIV-specific antibody and T-cell responses correlate with each other and with HIV DNA levels. The positive correlation between HIV immune responses and HIV DNA implies that the immune system is sensing, but not clearing, infected cells, perhaps because of immune dysfunction. Measuring immune responses to HIV antigens may provide insight into the impact of reservoir-reducing strategies
Predictors of Virologic Failure in HIV/AIDS Patients Treated with Highly Active Antiretroviral Therapy in BrasĂlia, Brazil During 2002–2008
Little data exists concerning the efficacy of the antiretroviral therapy in the Federal District in Brazil, therefore in order to improve HIV/AIDS patients’ therapy and to pinpoint hot spots in the treatment, this research work was conducted. Of 139 HIV/AIDS patients submitted to the highly active antiretroviral therapy, 12.2% failed virologically. The significant associated factors related to unresponsiveness to the lentiviral treatment were: patients’ place of origin (OR = 3.28; IC95% = 1.0–9.73; P = 0.032) and Mycobacterium tuberculosis infection (RR = 2.90; IC95% = 1.19–7.02; P = 0.019). In the logistic regression analysis, the remaining variables in the model were: patients’ birthplace (OR = 3.28; IC95% = 1.10–9.73; P = 0.032) and tuberculosis comorbidity (OR = 3.82; IC95% = 1.19–12.22; P = 0.024). The patients enrolled in this survey had an 88.0% therapeutic success rate for the maximum period of one year of treatment, predicting that T CD4+ low values and elevated viral loads at pretreatment should be particularly considered in tuberculosis coinfection, besides the availability of new antiretroviral drugs displaying optimal activity both in viral suppression and immunological reconstitution
T cells with high PD-1 expression are associated with lower HIV-specific immune responses despite long-term antiretroviral therapy
Objective: We evaluated frequencies of T cells with high PD-1 expression (PD-1HI) before and after long-term effective antiretroviral therapy (ART), and determined if frequencies on-ART correlated positively with measures of HIV persistence and negatively with HIV-specific responses.Methods:We enrolled individuals who started ART during chronic infection and had durable suppression of viremia for at least 4 years (N=99). We assessed PD-1HI T-cell frequencies at timepoints pre-ART and on-ART using flow cytometry, and evaluated how frequencies on-ART are associated with measures of HIV persistence, HIV-specific immune responses, and immune activation levels.Results:Pre-ART, PD-1HI CD4+ T cells correlated positively with viremia and negatively with CD4+ T-cell count. At year 1 on-ART, %PD-1HI CD4+ T cells decreased but then remained stable at 4 and 6-15 years on-ART, whereas %PD-1HI CD8+ T cells on-ART remained similar to pre-ART. PD-1HI CD4+ T cells correlated positively with HIV DNA pre-ART and on-ART, and with CD4+ T-cell activation on-ART. PD-1HI CD4+ T cells negatively correlated with HIV Gag-specific and Env-specific T-cell responses but not with CMV-specific or EBV-specific responses. PD-1HI CD8+ T cells trended towards a negative correlation with responses to Gag and Env, but not to CMV and EBV.Conclusion:PD-1HI T cells persist in blood despite prolonged suppression on ART, correlate with HIV DNA levels, and are associated with lower HIV-specific T-cell responses but not CMV-specific or EBV-specific responses, suggesting that these cells are HIV-specific. The findings support evaluating PD-1 blockade strategies for their effect on HIV persistence and HIV-specific immunity
Cumulative antiretroviral exposure measured in hair is not associated with measures of HIV persistence or inflammation among individuals on suppressive ART
Data on the relationship of antiretroviral exposure to measures of human immunodeficiency virus (HIV) persistence are limited. To address this gap, multiple viral, immunologic, and pharmacologic measures were analyzed from individuals with sustained virologic suppression on therapy (median 7 years) in the AIDS Clinical Trials Group A5321 cohort. Among 110 participants on tenofovir-(TFV)-disoproxil-fumarate (TDF)/emtricitabine (FTC)-containing regimens, we found no significant correlation between hair concentrations of individual antiretrovirals (ARVs) in the regimen and measures of HIV persistence (plasma HIV-1 RNA by single copy assay, cell-associated-DNA, cell-associated RNA) or soluble markers of inflammation. These findings suggest that higher systemic ARV exposure may not impact HIV persistence or inflammation
Clones of infected cells arise early in HIV-infected individuals
In HIV-infected individuals on long-term antiretroviral therapy (ART), more than 40% of the infected cells are in clones. Although most HIV proviruses present in individuals on long-term ART are defective, including those in clonally expanded cells, there is increasing evidence that clones carrying replication-competent proviruses are common in patients on long-term ART and form part of the HIV reservoir that makes it impossible to cure HIV infection with current ART alone. Given the importance of clonal expansion in HIV persistence, we determined how soon after HIV acquisition infected clones can grow large enough to be detected (clones larger than ca. 1 Ă— 105 cells). We studied 12 individuals sampled in early HIV infection (Fiebig stage III-V/VI) and 5 who were chronically infected. The recently infected individuals were started on ART at or near the time of diagnosis. We isolated more than 6,500 independent integration sites from peripheral blood mononuclear cells before ART was initiated and after 0.5-18 years of suppressive ART. Some infected clones could be detected approximately 4 weeks after HIV infection and some of these clones persisted for years. The results help to explain how the reservoir is established early and persists for years
Clinical trial of the anti-PD-L1 antibody BMS-936559 in HIV-1 infected participants on suppressive antiretroviral therapy
Background. Reversing immune exhaustion with an anti-PD-L1 antibody may improve human immunodeficiency virus type 1 (HIV-1)-specific immunity and increase clearance of HIV-1-expressing cells. Methods. We conducted a phase I, randomized, double-blind, placebo-controlled, dose-escalating study of BMS-936559, including HIV-1-infected adults aged >18 to 350 cells/ÎĽL and detectable plasma HIV-1 RNA by single-copy assay. Data on single infusions of BMS-936559 (0.3 mg/kg) versus placebo are described. The primary outcomes were safety defined as any grade 3 or greater or immune-related adverse event (AE) and the change in HIV-1 Gag-specific CD8+ T cell responses from baseline to day 28 after infusion. Results. Eight men enrolled: 6 received 0.3 mg/kg of BMS-936559, and 2 received placebo infusions. There were no BMS- 936559-related grade 3 or greater AEs. In 1 participant, asymptomatic hypophysitis (a protocol-defined immune-related AE) was identified 266 days after BMS-936559 infusion; it resolved over time. The mean percentage of HIV-1 Gag-specific CD8+ T cells expressing interferon Îł increased from baseline (0.09%) through day 28 (0.20%; P = .14), driven by substantial increases in 2 participants who received BMS-936559. Conclusions. In this first evaluation of an immunologic checkpoint inhibitor in healthy HIV-1-infected persons, single lowdose BMS-936559 infusions appeared to enhance HIV-1-specific immunity in a subset of participants
Brief Report: No Evidence for an Association between Statin Use and Lower Biomarkers of HIV Persistence or Immune Activation/Inflammation during Effective ART
Background: Statins exert pleiotropic anti-inflammatory and immune-modulatory effects, which might translate into antiviral activity. We evaluated whether reported current statin exposure is associated with lower levels of markers of HIV persistence and immune activation/inflammation. Methods: We compared levels of markers of HIV viral persistence [cell-associated HIV RNA (CA-RNA), CA-DNA, and single copy assay plasma HIV RNA] and immune activation/inflammation (IL-6, IP-10, neopterin, sCD14, sCD163, and TNF-alpha) between statin users and nonusers among participants of ACTG A5321 who initiated antiretroviral therapy (ART) during chronic infection and maintained virologic suppression (HIV-1 RNA levels ≤50 copies/mL) for ≥3 years. Results: A total of 303 participants were analyzed. Median time on the current statin was 2.9 years (1.2-5.1). There were no differences between statin users and nonusers in levels of CA-DNA (median 650 vs. 540 copies/106 CD4+ T cells; P = 0.58), CA-RNA (53 vs. 37 copies/106 CD4+ T cells; P = 0.12), or single copy assay (0.4 vs. 0.4 copies/mL; P = 0.45). Similarly, there were no significant differences between statin users and nonusers in markers of inflammation/activation, except for IP-10 (137 vs. 118 pg/mL; P = 0.028). Findings were unchanged after adjustment for factors including pre-ART CD4 and HIV RNA, and years on ART. Conclusions: In this cohort of persons on long-term suppressive ART, current statin use was not associated with lower levels of HIV persistence or immune activation/inflammation. These results do not support a major role for statins in reducing HIV persistence, although an early transient effect cannot be excluded. Prospective, randomized studies are needed to confirm these findings
Persistent HIV-infected cells in cerebrospinal fluid are associated with poorer neurocognitive performance
BACKGROUND. Persistence of HIV in sanctuary sites despite antiretroviral therapy (ART) presents a barrier to HIV remission and may affect neurocognitive function. We assessed HIV persistence in cerebrospinal fluid (CSF) and associations with inflammation and neurocognitive performance during long-term ART. METHODS. Participants enrolled in the AIDS Clinical Trials Group (ACTG) HIV Reservoirs Cohort Study (A5321) underwent concurrent lumbar puncture, phlebotomy, and neurocognitive assessment. Cell-associated HIV DNA and HIV RNA (CA-DNA, CA-RNA) were measured by quantitative PCR (qPCR). in peripheral blood mononuclear cells (PBMCs) and in cell pellets from CSF. In CSF supernatant and blood plasma, cell-free HIV RNA was quantified by qPCR with single copy sensitivity, and inflammatory biomarkers were measured by enzyme immunoassay. RESULTS. Sixty-nine participants (97% male, median age 50 years, CD4 696 cells/mm3, plasma HIV RNA <100 copies/mL) were assessed after a median 8.6 years of ART. In CSF, cell-free RNA was detected in 4%, CA-RNA in 9%, and CA-DNA in 48% of participants (median level 2.1 copies/103 cells). Detection of cell-free CSF HIV RNA was associated with higher plasma HIV RNA (P = 0.007). CSF inflammatory biomarkers did not correlate with HIV persistence measures. Detection of CSF CA-DNA HIV was associated with worse neurocognitive outcomes including global deficit score (P = 0.005), even after adjusting for age and nadir CD4 count. CONCLUSION. HIV-infected cells persist in CSF in almost half of individuals on long-term ART, and their detection is associated with poorer neurocognitive performance
Impact of SARS-CoV-2 Resistance to Antiviral Monoclonal Antibody Therapy on Neutralizing Antibody Response
Background: Anti-SARS-CoV-2 monoclonal antibodies (mAbs) have played a key role as an antiviral against SARS-CoV-2, but there is a potential for resistance to develop. The interplay between host antibody responses and the development of monoclonal antibody (mAb) resistance is a critical area of investigation. In this study, we assessed host neutralizing antibody (nAb) responses against both ancestral virus and those with treatment-emergent E484K bamlanivimab resistance mutations. Methods: Study participants were enrolled in the ACTIV-2/Advancing Clinical Therapeutics Globally (ACTG) A5401 phase 2 randomized, placebo-controlled trial of bamlanivimab 700 mg mAb therapy (NCT04518410). Anterior nasal and nasopharyngeal swabs were collected for SARS-CoV-2 RNA testing and S gene next-generation sequencing to identify the E484K bam-lanivimab resistance mutation. Serum nAb titers were assessed by pseudovirus neutralization assays. Results: Higher baseline (pre-treatment) nAb titers against either ancestral or E484K virus was associated with lower baseline viral load. Participants with emerging resistance had low levels of nAb titers against either ancestral or E484K nAb at the time of study entry. Participants with emergent E484K resistance developed significantly higher levels of E484K-specific nAb titers compared to mAb-treated individuals who did not develop resistance. All participants who developed the E484K mAb resistance mutation were eventually able to clear the virus. Conclusion: Emerging drug resistance after SARS-CoV-2-specific mAb therapy led to a height-ened host neutralizing antibody response to the mAb-resistant variant that was associated with eventual viral clearance. This demonstrates the interplay between the antiviral treatment-directed viral evolution and subsequent host immune response in viral clearance
Recommendations for analytical antiretroviral treatment interruptions in HIV research trials: report of a consensus meeting
Analytical antiretroviral treatment interruption (ATI) is an important feature of HIV research, seeking to achieve sustained viral suppression in the absence of antiretroviral therapy (ART) when the goal is to measure effects of novel therapeutic interventions on time to viral load rebound or altered viral setpoint. Trials with ATIs also intend to determine host, virological, and immunological markers that are predictive of sustained viral control off ART. Although ATI is increasingly incorporated into proof-of-concept trials, no consensus has been reached on strategies to maximise its utility and minimise its risks. In addition, differences in ATI trial designs hinder the ability to compare efficacy and safety of interventions across trials. Therefore, we held a meeting of stakeholders from many interest groups, including scientists, clinicians, ethicists, social scientists, regulators, people living with HIV, and advocacy groups, to discuss the main challenges concerning ATI studies and to formulate recommendations with an emphasis on strategies for risk mitigation and monitoring, ART resumption criteria, and ethical considerations. In this Review, we present the major points of discussion and consensus views achieved with the goal of informing the conduct of ATIs to maximise the knowledge gained and minimise the risk to participants in clinical HIV research