HIV Plasma Viremia Research Articles

Effects of COVID-19 mRNA vaccination on HIV viremia and reservoir size.

The immunogenic nature of coronavirus disease 2019 (COVID-19) mRNA vaccines led to some initial concern that these could stimulate the HIV reservoir. We analyzed changes in plasma HIV loads (pVL) and reservoir size following COVID-19 mRNA vaccination in 62 people with HIV (PWH) receiving antiretroviral therapy (ART), and analyzed province-wide trends in pVL before and after the mass vaccination campaign. Longitudinal observational cohort and province-wide analysis. Sixty-two participants were sampled prevaccination, and one month after their first and second COVID-19 immunizations. Vaccine-induced anti-SARS-CoV-2-Spike antibodies in serum were measured using the Roche Elecsys Anti-S assay. HIV reservoirs were quantified using the intact proviral DNA assay; pVL were measured using the cobas 6800 (lower limit of quantification: 20 copies/ml). The province-wide analysis included all 290 401 pVL performed in British Columbia, Canada between 2012 and 2022. Prevaccination, the median intact reservoir size was 77 [interquartile range (IQR): 20-204] HIV copies/million CD4 + T-cells, compared to 74 (IQR: 27-212) and 65 (IQR: 22-174) postfirst and -second dose, respectively (all comparisons P > 0.07). Prevaccination, 82% of participants had pVL <20 copies/ml (max: 110 copies/ml), compared to 79% postfirst dose (max: 183 copies/ml) and 85% postsecond dose (max: 79 copies/ml) ( P > 0.4). There was no evidence that the magnitude of the vaccine-elicited anti-SARS-CoV-2-Spike immune response influenced pVL nor changes in reservoir size ( P > 0.6). We found no evidence linking the COVID-19 mass vaccination campaign to population-level increases in detectable pVL frequency among all PWH in the province, nor among those who maintained pVL suppression on ART. We found no evidence that COVID-19 mRNA vaccines induced changes in HIV reservoir size nor plasma viremia.

SARS-CoV-2 mRNA Vaccines Induce Greater Complement Activation and Decreased Viremia and Nef Antibodies in Men With HIV-1.

Immune dysregulation in people with human immunodeficiency virus-1 (PWH) persists despite potent antiretroviral therapy and, consequently, PWH tend to have lower immune responses to licensed vaccines. However, limited information is available about the impact of mRNA vaccines in PWH. This study details the immunologic responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccines in PWH and their impact on HIV-1. We quantified anti-S immunoglobulin G (IgG) binding and neutralization of 3 SARS-CoV-2 variants of concern and complement activation in blood from virally suppressed men with HIV-1 (MWH) and men without HIV-1 (MWOH), and the characteristics that may impact the vaccine immune responses. We also studied antibody levels against HIV-1 proteins and HIV-1 plasma RNA. MWH had lower anti-S IgG binding and neutralizing antibodies against the 3 variants compared to MWOH. MWH also produced anti-S1 antibodies with a 10-fold greater ability to activate complement and exhibited higher C3a blood levels than MWOH. MWH had decreased residual HIV-1 plasma viremia and anti-Nef IgG approximately 100 days after immunization. MWH respond to SARS-CoV-2 mRNA vaccines with lower antibody titers and with greater activation of complement, while exhibiting a decrease in HIV-1 viremia and anti-Nef antibodies. These results suggest an important role of complement activation mediating protection in MWH.

Humoral Response after Two Doses of BNT162b2 mRNA Vaccine Has a Role in Predicting Response after Three Doses That Is Related to Plasma HIV Viremia and Nadir CD4+ Cell Count in HIV-Positive Patients.

We investigated the spike IgG levels of HIV+ patients on antiretroviral therapy six months after they received their second dose (T2) and six months after the third dose (T3) of the BNT162b2 mRNA vaccine, as well as the influence of different levels of plasma HIV viremia of overall CD4+ cell count and nadir value on the humoral time course. One hundred eighty-four patients were enrolled. The median age was 55 years, the median CD4+ cell count was 639 cells/mm3 and the median nadir value was 258 cells/mm3. On the basis of all tests performed during the study period, persistently undetectable plasma HIV RNA (PUD) was found in 66 patients, low-level viremia (LLV) in 57 and ongoing viremia (OV) in 61. Serum levels of IgG antibodies against a trimeric S-protein antigen were tested with DiaSorin Liaison SARS-CoV-2 TrimericS IgG and the response was classified as optimal (>75th percentile), intermediate (50th−25th percentile) and low (<25th percentile). The frequencies of the three different patterns of plasma HIV viremia (PUD, LLV and OV) were comparable in patients with low, intermediate and optimal IgG response evaluated at T2, with no difference in overall CD4+ cell count or nadir count. At T3, 92.9% of patients achieved an optimal response: T2 response proved to be the most important factor in predicting T3 optimal response in patients with LLV and OV.A nadir value ≤ 330 cells/mm3 had 100% sensitivity in predicting a non-optimal response. In conclusion, we demonstrated the persistence of anti-spike IgG, with high serum levels occurring in most patients six months after the third dose of the BNT162b2 mRNA vaccine and a predictive role of humoral response at T2 in subjects with detectable plasma HIV viremia. Immunological alterations related to past immunodeficiency may persist despite immune reconstitution, and the nadir value could be a useful tool for elaborating personalized vaccine schedules.

Immunological factors associated with discordant virological response postcombination antiretroviral therapy in pediatric human immunodeficiency virus infection.

Evaluation of immunological factors responsible for discordant virological responses postcombination antiretroviral therapy (cART) in human immunodeficiency virus (HIV)-positive children aged &lt;5 years. Immunological profiling of enrolled 30 HIV-positive children was done at enrollment, 6 and 12 months. Flow cytometric analysis was performed for enumeration of counts and percentage of CD4⁺, CD8⁺, and CD19⁺ cells; expression of CD19, CD86, PD-1, CD3, CD8 and CD28 on lymphocytes was evaluated using whole blood staining technique with monoclonal antibodies. HIV-1 viral load was quantified using a real-time polymerase chain reaction. Serum levels of immunoglobulin G (IgG), immunoglobulin A (IgA), immunoglobulin (IgM), and interleukin (IL)-7 were quantitated using quantitative enzyme-linked immunosorbent assay kits. The HIV-infected children were categorized into virological responders (VRs; HIV-1 plasma viral load &lt;47 copies/mL) and virological nonresponders (VNRs; HIV-1 plasma viral load &gt;1000 copies/mL) following 1-year cART. The frequency of CD28⁺ CTLs cells was higher (P &lt; 0.0001), and the frequency of CD28-CTLs cells was lower (P &lt; 0.0001) in VRs than VNRs. CD28⁺ and CD28-CTLs cells correlated with HIV-1 plasma viremia (r = -0.4695, P = 0.01; r = 0.40, P = 0.03, respectively). VRs had higher CD19 percentage (P = 0.04) and count (P = 0.01) than VNRs. CD19⁺ B cells in the VRs had lower expression of CD86 (P = 0.03) and PD-1 (P = 0.002) than VNRs. VR had lower levels of serum IgG (P = 0.03), IgM (P = 0.04), and IL-7 (P = 0.01) than VNRs. High baseline B-cell counts, lower serum IgG, IgM, IL-7 levels, lower activation and exhaustion of B cells, and higher frequency of CD28⁺ CTLs are associated with positive virological response, whereas elevated CD28-CTLs are associated with the poor virological outcomes in HIV-infected children.

Ebv-Mir-BART11-3p, Ebv-Mir-BART9 and Ebv-Mir-BART10 Are Present in the Plasma of HIV-Infected Subjects with Lymphoma and Are Potential Lymphoma Biomarkers

Epstein Barr virus (EBV) has been implicated in the lymphomagenesis, particularly of HIV-related lymphomas. EBV-infected cells are able to share miRNAs with other cells via exosomes and certain EBV-miRNAs were found in cells not infected with the virus but from patients with increased levels of EBV copies in plasma such as HIV-infected individuals. Thus, EBV-miRNAs might be detected in the plasma and might be relevant for the diagnosis and follow-up of HIV-related lymphomas.This case-control study included a group of 26 HIV-infected patients with lymphoma that responded to treatment and a control-group of HIV-infected subjetcs without lymphoma matched for age, gender, CD4-lymphocyte counts, plasma HIV viremia and time from HIV infection. We evaluated the presence of 43 EBV-miRNAs in frozen plasma samples from patients with lymphoma at diagnosis (Dx-group, N=26), one year before diagnosis (Pre-group, N=15) and complete response (CR-group, N=26). RNA was extracted from 200µl of plasma using Trizol LS (Ambion, Carlsbad, CA) and cel-miR-39 was used as spike-in. The detection of EBV-miRNAs was assessed by QRT-PCR in a BioMark™ HD System of Fluidigm (San Francisco, CA) using TaqMan® microRNA assays and TaqMan Universal PCR Master Mix (Applied Biosystems, Foster City, CA). The following clinical and biological parameters were collected from records: age, gender, ECOG score, extranodal and bulky disease, B symptoms, Ann-Arbor stage, serum lactate dehydrogenase (LDH) and beta2-microglobulin, International Prognostic Index (IPI), HCV and HBV serology, history of opportunistic infection and of AIDS-defining illnesses, onset of combination antiretroviral therapy, CD4-lymphocyte counts, plasma HIV viremia. McNemar's and Wilcoxon tests were used for paired comparisons between groups. P-values of less than .05 were considered statistically significant.Overall, 30 EBV-miRNAs were detected in the Dx-group whereas only 8 EBV-miRNAs where found in the control-group and 19 in the CR-group. EBV-miRNAs were detected more frequently in the Dx-group (17 out of 26) than in the control-group (7 out of 26) (P =.002) and in the CR-group (11 out of 26) (P=.02). The presence of 6 EBV-miRNAs (ebv-miR-BART11-3p, ebv-miR-BART9, ebv-miR-BART10, ebv-miR-BART15, ebv-miR-BART31, and ebv-miR-BART19) could be associated with the lymphoma condition, since they were detected significantly different in the Dx-group and the control-group (Figure 1). Importantly, 3 of those EBV-miRNAs (ebv-miRBART11-3p, ebv-miR-BART9 and ebv-miRBART10) were found to be significantly less frequent in the CR group, reinforcing the idea that they could be derived from lymphoma cells and be used as biomarkers for diagnosis and follow up of HIV-related lymphoma. EBV-miRNAs cannot be used as early biomarkers of lymphoma in HIV-infected patients because none of the 3 EBV-miRNAs associated with lymphoma was significantly found in samples before diagnosis. The detection in plasma of ebv-miR-BART11-3p, ebv-miR-BART10 or ebv-miR-BART9 was not associated with having tumor cells infected with EBV (Figure 1). Only the detection of ebv-miR-BART9 was associated with detectable EBV loads [7/14 (50%) vs. 1/12 (8.3%), P=.036] (Figure 1). The following were the statistically significant associations between the presence of the 3 potential EBV-miRNA lymphoma biomarkers and the clinical-biological features studied. The presence of ebv-miR-BART10 in plasma was associated with IPI>2 [8/14 (57.1%) vs. 1/9 (11.1%), P=.004] and ECOG>2 [8/14 (57.1%) vs. 1/11 (9.1%), P=.011]. Also, more patients with ebv-miR-BART11-3p expression in plasma had ECOG>2 than patients without it [7/13 (53.8%) vs. 1/12 (8.3%), P=.030].Ebv-miR-BART11-3p, ebv-miR-BART9 and ebv-miR-BART10 can be detected in the plasma of patients with HIV-related lymphoma, independently of the presence of EBV in tumor cells or of EBV plasma viremia. They are potential biomarkers of lymphoma to be used in the diagnosis and follow up of HIV-infected subjects with the advantage of being easily determined by QRT-PCR employing noninvasive procedures.This work was supported in part by 2014 SGR225 (GRE) from CERCA Programme/Generalitat de Catalunya, and by funds from Josep Carreras International Foundation, “la Caixa” Foundation, DKMS, and Celgene Spain. [Display omitted] DisclosuresBaptista:DKMS: Research Funding; la Caixa Foundation: Research Funding; Carreras International Foundation: Research Funding; CERCA Programme/Generalitat de Catalunya: Research Funding; Celgene Spain: Research Funding. Sancho:Roche: Honoraria; Laboratorios Servier: Consultancy; Mundipharma: Honoraria; Kern Pharma: Honoraria; Gilead: Honoraria; Celgene: Honoraria; Janssen: Honoraria. Ribera:Celgene: Honoraria; Janssen: Honoraria; Gilead: Honoraria; Amgen Inc.: Research Funding, Speakers Bureau; Pfizer: Research Funding, Speakers Bureau; Incyte: Research Funding, Speakers Bureau; ARIAD: Research Funding, Speakers Bureau; Roche: Honoraria. Navarro:Celgene Spain: Research Funding; DKMS: Research Funding; la Caixa Foundation: Research Funding; Josep Carreras International Foundation: Research Funding; CERCA Programme/Generalitat de Catalunya: Research Funding.

HIV-DNA content in pTfh cells is associated with residual viremia in elite controllers.

The source of residual HIV viremia is highly debated and its potential relationship with the HIV reservoir has not been clarified. Herein, we analysed the cell-associated HIV-DNA content in two important cell compartments of the HIV reservoir, resting CD4+ T memory (Trm) and peripheral T follicular helper (pTfh) cells, and the association with the residual HIV viremia in individuals with spontaneous HIV replication control (elite controllers, EC group) and in individuals with antiretroviral therapy (ART)-mediated HIV replication control (cART group). A cross-sectional study. Seventeen chronically HIV-infected patients with suppressed HIV replication were included. Cell-associated HIV-DNA was measured by ultrasensitive digital-droplet-PCR in purified Trm and pTfh cells. Residual HIV plasma viremia was quantified using a single-copy assay with a sensitivity of 0.3 HIV-RNA copies/ml. A significant and positive correlation was demonstrated between HIV-DNA levels in pTfh cells and residual plasma viral load (rpVL) (rho = 0.928, P = 0.008) in HIV-positive elite controllers, but not in HIV-positive treated patients, despite the lower levels of cell-associated HIV-DNA found in elite controllers compared with cART patients in pTfh cells [176 (77-882) vs. 608 (361-860) copies/million cells, respectively; P = 0.05]. This association suggests that pTfh cells could have an important contribution to persistent viremia in elite controllers. This could be the consequence of a more limited control of HIV replication in elite controllers with higher transcriptional activity of HIV in pTfh cells of elite controllers than that in cART patients.

An Integrated Spatial Dynamics-Pharmacokinetic Model Explaining Poor Penetration of Anti-retroviral Drugs in Lymph Nodes.

Although combined anti-retroviral therapy (cART) suppresses plasma HIV viremia below the limit of detection in a majority of HIV patients, evidence is emerging that the distribution of the anti-retroviral drugs is heterogeneous in tissue. Clinical studies measuring antiretroviral drug concentrations in lymph nodes (LNs) revealed lower concentrations compared to peripheral blood levels suggesting poor drug penetration properties. Our current study is an attempt to understand this poor anti-retroviral drug penetration inside lymph node lobules through integrating known pharmacokinetic and pharmacodynamic (PK/PD) parameters of the anti-retroviral drugs into a spatial model of reaction and transport dynamics within a solid lymph node lobule. Simulated drug penetration values were compared against experimental results whenever available or matched with data that is available for other drugs in a similar class. Our integrated spatial dynamics pharmacokinetic model reproduced the experimentally observed exclusion of antivirals from lymphoid sites. The strongest predictor of drug exclusion from the lymphoid lobule, independent of drug class, was lobule size; large lobules (high inflammation) exhibited high levels of drug exclusion. PK/PD characteristics associated with poor lymphoid penetration include high cellular uptake rates and low intracellular half-lives. To determine whether this exclusion might lead to ongoing replication, target CD4+ T cell, infected CD4+ T cell, free virus, and intracellular IC50 values of anti-retroviral drugs were incorporated into the model. Notably, for median estimates of PK/PD parameters and lobule diameters consistent with low to moderate inflammation, the model predicts no ongoing viral replication, despite substantial exclusion of the drugs from the lymphoid site. Monte-Carlo studies drawn from the prior distributions of the PK/PD parameters predicts increases in site-specific HIV replication in a small fraction of the patient population for lobule diameters greater than 0.2 mm; this fraction increases as the site diameter/ inflammation level increases. The model shows that cART consisting of two nRTIs and one PI is the most likely treatment combination to support formation of a sanctuary site, a finding that is consistent with clinical observations.

Concurrent administration of IFN\u03b114 and cART in TKO-BLT mice enhances suppression of HIV-1 viremia but does not eliminate the latent reservoir

Combination antiretroviral therapy (cART) prevents HIV-1 replication but does not eliminate the latent reservoir and cure the infection. Type I interferons (IFN) mediate antiviral effects through different mechanisms than cART. We previously showed that IFNα14 is the most potent IFNα subtype against HIV-1 and that it can significantly reduce the HIV-1 proviral reservoir. This study sought to determine whether combining cART with IFNα14 therapy would produce greater reductions in HIV-1 viral and proviral loads than ART alone. Immunodeficient Rag2−/−γc−/−CD47−/− C57BL/6 mice were humanized by the BLT method, infected with HIV-1JR-CSF and the in vivo efficacy of cART was compared with combined cART/IFNα14 therapy. Infection was allowed to establish for 6 weeks prior to 4 weeks of treatment with oral cART either with or without IFNα14. Plasma viral RNA and splenic CD4+ T cell viral DNA levels were measured immediately after treatment and after 2 weeks of therapy interruption. Augmentation of cART with IFNα14 resulted in significantly enhanced suppression of HIV-1 plasma viremia. However, no significant reduction in total viral DNA was detectable. Furthermore, virus rebounded after treatment interruption to similar levels in both groups. Thus, augmentation of cART with IFNα14 resulted in a more pronounced reduction of HIV viremia levels over cART alone, but the effect was not potent enough to be detected at the viral DNA level or to prevent virus rebound following therapy interruption in immune system-humanized mice.

PP 3.1 - Automated high-throughput quantification of persistent HIV-1 plasma viremia in individuals on ART

PP 3.1 - Automated high-throughput quantification of persistent HIV-1 plasma viremia in individuals on ART

Remission of an HHV8-related extracavitary primary effusion lymphoma in an HIV-positive patient during antiretroviral treatment containing dolutegravir

BackgroundHuman herpes virus 8 (HHV8) is the causative agent of Kaposi’s sarcoma and has been associated with an increasing number of hematologic diseases such as primary effusion lymphoma (PEL) (both classic and extracavitary form), multicentric Castleman disease and the germinotropic lymphoproliferative disorder. PEL is a rare B cell non-Hodgkin lymphoma that primarily affects immunocompromised patients; aggressive chemotherapy and antiretroviral therapy (ART) with protease inhibitors have been used, with poor results. We present a case of extracavitary PEL in an HIV-infected patient, regressed after ART initiation.Case presentationA 42-year-old male was admitted to the emergency room because of several months of malaise, fever and progressive deterioration of the general conditions. On physical examination soft non-painful subcutaneous masses were palpable at retronuchal, retroauricolar and thoracic regions. HIV serology resulted positive: HIV plasma viremia was 782,270 copies/mL, CD4 103 cells/mL. The excision of one of the masses, metabolically active at a positron emission tomography (PET-CT) scan, revealed an HHV8-related extracavitary PEL. HHV8 plasma viremia was 44,826 copies/mL. ART with tenofovir alafenamide/emtricitabine/dolutegravir was started together with ganciclovir for cytomegalovirus chorioretinitis. The progressive disappearance of the masses was seen after 6 weeks of ART, and a PET-CT scan resulted completely negative at 3 months. After 19 months of ART the patient was in remission of PEL, HIV viremia was undetectable (< 20 copies/mL), CD4 count was 766 cells/mL and HHV8 viremia was undetectable.ConclusionsIn this clinical case, the complete regression of PEL has been achieved after the immune recovery, as a consequence of ART introduction, without chemotherapy. It cannot be excluded that ganciclovir, used for the treatment of CMV chorioretinitis, may have contributed to the control of HHV8 replication. Whether to try or not a conservative approach in HIV-infected PEL patients must be carefully evaluated, considering the patient’s characteristics and the prognostic factors.

A Phase I, Randomized, Controlled Clinical Study of CC-11050 in People Living With HIV With Suppressed Plasma Viremia on Antiretroviral Therapy (APHRODITE).

Phosphodiesterase 4 inhibitors (PDE4i) are novel anti-inflammatory medications that have been approved for rheumatologic diseases and have been tested as host-directed therapy in tuberculosis. We examined the safety of CC-11050, a potent PDE4i in people living with HIV (PLWH) with suppressed HIV plasma viremia. We hypothesized that CC-11050 could be used to modulate HIV-related inflammation. Thirty PLWH on antiretroviral therapy (ART) ≥ 1 year with suppressed HIV viremia were enrolled and randomized 2:1 to 12 weeks of CC-11050 200mg twice daily or placebo with follow-up at weeks 2, 4, 8, 12, and 16. Primary endpoint was safety. Secondary endpoints were the effect of CC-11050 on cytokines, monocyte, and T-cell activation and potential pharmacokinetic interaction between CC-11050 and Efavirenz (EFV). At baseline, median age was 49.5 years and CD4 count 459 cells/µL. Most frequent adverse events (grade 1 and 2 only) in CC-11050 group were headache, diarrhea, nausea, cough, nasal congestion, and restlessness. Over a 12-week period, the CC-11050 group had lower level of IL-8, adjusted for baseline level, group, and week (0.72-fold, P = .02), lower percentage of NK cells (0.87-fold, P = .02) and higher IL-6 level (1.48-fold, P = .03) compared to placebo (0.87-fold, P = .02). CC-11050 and EFV co-administration did not reveal any pharmacokinetic interaction. CC-11050 was well tolerated in PLWH, without affecting CD4 counts or plasma viremia, and led to a decrease in NK cells and plasma IL-8 level after 12-weeks of administration. Further study will be needed to elucidate the efficacy of CC-11050 as potential anti-inflammatory adjuvant strategy in HIV.

A phase 1, randomized, controlled clinical study of CC-11050 in people living with HIV with suppressed plasma viremia on antiretroviral therapy (APHRODITE)

Abstract Background Phosphodiesterase 4 inhibitors (PDE4i) block the degradation of cyclic adenosine monophosphate and modulate both innate and adaptive immune responses. PDE4i have been approved for rheumatologic diseases and tested as host-directed therapy in TB. We examined the safety of CC-11050, a new potent PDE4i, in HIV+ people with suppressed viral load (VL). We hypothesized that CC-11050 could be used to modulate HIV-related inflammatory responses. Methods Thirty HIV+ participants, on antiretroviral therapy (ART) ≥ 1 year with HIV VL &amp;lt;50 copies/mL were randomized 2:1 to 12 weeks of CC-11050 200mg BID or placebo with follow-up at weeks 2, 4, 8, 12 and 16. Primary endpoint was safety. We also assessed the effect of CC-11050 on CD4+, CD8+, NK, VL, plasma cytokines, monocyte and T-cell activation. Results At baseline, median age was 49.5 years and CD4+ 459 cells/μL. Most frequent adverse events (only grades 1–2) in CC-11050 group were headache, diarrhea, nausea, cough and nasal congestion. The CC-11050 group had lower IL-8 level after adjustment for baseline level, group and week (0.72 fold, p=0.02) and lower %NK cells compared to placebo (0.87 fold, p=0.02). At week 12, the CC-11050 group had higher %CD14++CD16+ monocytes than placebo (median 58.5% vs 50.7%, p=0.03). There was no significant effect on plasma HIV viremia, assessed by single copy assay and on cell-associated DNA and RNA in PBMC. Conclusions CC-11050 was well tolerated in HIV+ participants without affecting controlled viremia. CC-11050 had an effect on innate immune mechanisms, by decreasing NK cells and IL-8 level and increasing intermediate monocytes. Further study is needed to elucidate the efficacy of CC-11050 as potential anti-inflammatory adjuvant strategy in HIV.

Passive infusion of Fc-modified neutralizing antibodies does not affect the dynamics of plasma virus decay in SHIV-infected macaques

Abstract Passive neutralizing antibody (NAb) infusion leads to a reduction of HIV plasma viremia in infected people as well as in SHIV-infected rhesus macaques. Potential mechanisms of viral reduction include neutralization of free virus as well as Fc-dependent effector functions that can clear infected cells. We generated several Fc variants of the human IgG1 NAb VRC07-523LS and characterized them for neutralization, complement binding, ADCC, phagocytosis, and binding to rhesus FcgR. Based on these assays, we down selected two variants, LALA and DEL, that showed knock-out or increase in ADCC and phagocytosis respectively, with complement binding knocked out in both. The parental, LALA and DEL variants of VRC07-523LS were administered at a single dose of 20 mg/kg i.v. to rhesus macaques chronically infected with SHIV-SF162P3 for 6–14 weeks (n=6 to 10 per group). Animals were followed for rate of plasma virus decay and antibody PK. All groups showed similar characteristics: 1) plasma virus decay was delayed for 24h after NAb infusion 2) the rate of plasma virus decay was the same between day 1 and day 5, and 3) plasma virus decay was independent of FcgRIII genotype. Pharmacokinetic analysis showed that serum NAb concentrations in the VRC07-523LS, LALA and DEL groups were maintained at greater than ten-fold excess of the in vitro IC80 against SHIV SF162P3 throughout the period of investigation. Further, unlike VRC07-523LS-LALA, VRC07-523LS-DEL was able to engage natural killer cells and monocytes and mediate both HIV envelope-dependent ADCC and phagocytosis. These results show that the initial impact on plasma viremia by passive NAb therapy is predominantly mediated by virus neutralization rather than ADCC or phagocytosis.

Cytomegalovirus, Epstein-Barr virus and human herpesvirus 8 salivary shedding in HIV positive men who have sex with men with controlled and uncontrolled plasma HIV viremia: a 24-month longitudinal study

BackgroundThis longitudinal study described Cytomegalovirus (CMV) DNA, Epstein-Barr (EBV) DNA and human herpesvirus 8 (HHV-8) DNA asymptomatic salivary shedding in HIV-positive men who have sex with men (MSM). We aimed to 1-analyze frequency and persistence of herpesvirus shedding, 2-correlate herpesvirus positivity and HIV viroimmunological parameters and 3-assess the association between HIV-RNA suppression and herpesvirus replication.MethodsHerpesvirus DNA was tested with an in-house real-time PCR in 2 salivary samples obtained at T0 and T1 (24 months after T0). HIV-RNA was evaluated in the 24 months prior to T0 and in the 24 months prior to T1; MSM were classified as successfully suppressed patients (SSPs), viremic patients (VPs) and partially suppressed patients (PSPs). EBV DNA load was classified as low viral load (EBV-LVL, value ≤10,000 copies/ml) and as high viral load (EBV-HVL,> 10,000 copies/ml). Mann-Whitney U test tested the difference of the median between groups of patients. Chi-squared test and Fisher’s exact test compared categorical variables according to the frequencies. Kruskal-Wallis test compared continuous data distributions between levels of categorical variables.ResultsNinety-two patients (median CD4+ count 575 cells/mm3, median nadir 330 CD4+ cells/mm3) were included: 40 SSPs,33 VPs and 19 PSPs. The more frequently single virus detected was EBV, both at T0 and at T1 (in 67.5 and 70% of SSPs, in 84.8 and 81.8% of VPs and in 68.4 and 73.7% of SPSs) and the most frequently multiple positivity detected was EBV + HHV-8. At T1, the percentage of CMV positivity was higher in VPs than in SSPs (36.4% vs 5%, p < 0.001), the combined shedding of HHV-8, CMV and EBV was present only in VPs (15.1%, p = 0.01 respect to SSPs) and no VPs confirmed the absence of shedding found at T0 (vs 17.5% of SSPs, p = 0.01). EBV-HVL was more frequent in VPs than in SSPs: 78.6% at T0 (p = 0.03) and 88.9% at T1 (p = 0.01).ConclusionsThe relationship between uncontrolled plasma HIV viremia and CMV, EBV, and HHV-8 shedding is multifaceted, as demonstrated by the focused association with EBV DNA load and not with its frequency and by the persistent combined detection of two oncogenic viruses as EBV and HHV-8 regardless of HIV virological control.

CD8+ T cell-mediated inhibition of HIV-1.

Abstract CD8+ T cells contribute to the control of viral infections, including HIV-1. Previous studies have reported that CD8+-mediated virus inhibition is predictive of subsequent HIV plasma viremia and CD4+T cell decline in HIV-infected, antiretroviral naïve individuals; higher virus inhibition is associated with a better clinical outcomes. Ex vivo CD8+ T cell-mediated inhibition of HIV replication is measured after co-culture of CD8+ T cells with HIV-1 super-infected, autologous CD4+ T cells, at different effector to target ratios. We adapted and standardized the CD8+ T cell virus inhibition assay (CD8-VIA) for use as an endpoint assay in therapeutic testing of HIV-1 T cell vaccines. CD8+ T cells from HIV infected, durably (&amp;gt;2 years) antiretroviral suppressed participants (n=11) were co-cultured with JR-CSF infected autologous CD4+ T cells at E:T ratios ranging from 1/2:1 to 1/160:1, generating CD8+ T cell virus inhibition curves for each participant. IC50 values varied by 100-fold across participants suggesting that CD8+ T cells harbor a broad range of virus inhibitory capacity even when viremia in participants is durably suppressed. Ongoing studies are comparing IC50 values to other measurements (magnitude, specificity, avidity, proliferation and production of cytokines and lytic molecules) of HIV-specific T cell immunity to understand the critical determinants of CD8+ T cell inhibitory capacity.

Soluble CD163 and soluble CD14 plasma levels but not cellular HIV-DNA decrease during successful interferon-free anti-HCV therapy in HIV-1-HCV co-infected patients on effective combined anti-HIV treatment.

Soluble CD163, soluble CD14 and cellular HIV-1-DNA levels reflect two different aspects of HIV infection: immune activation and the reservoir of infected cells. The aim of this study was to describe their relationships in a cohort of HIV-HCV co-infected patients successfully treated for both HCV and HIV infections. Fifty-five patients were recruited and studied prior to the start of direct-acting antivirals (DAAs) (T0), at week 12 of DAA treatment (T1) and 24weeks after T0 (T2). The subjects were classified as having undetectable plasma HIV viraemia (UV) or low-level viraemia (LLV) in the 18months before T2. Plasma levels of sCD163 and of sCD14 were comparable in patients with UV and in subjects with LVL at T0, T1 and T2. The HIV DNA level was positively correlated with LLV but not with sCD163 and sCD14 levels; these two markers of inflammation were positively correlated (p = 0.017). Soluble CD163 and sCD14 decreased over time from T0 to T2 (p = 0.000 and p = 0.034, respectively). In conclusion, the significant decrease in sCD163 and sCD14 levels in patients cured of HCV infection, regardless of the presence of LLV, suggests a main role for HCV in immune activation in HIV-HCV co-infected patients.

Dynamics of CD4 and CD8 T-Cell Subsets and Inflammatory Biomarkers during Early and Chronic HIV Infection in Mozambican Adults.

During primary HIV infection (PHI), there is a striking cascade response of inflammatory cytokines and many cells of the immune system show altered frequencies and signs of extensive activation. These changes have been shown to have a relevant role in predicting disease progression; however, the challenges of identifying PHI have resulted in a lack of critical information about the dynamics of early pathogenic events. We studied soluble inflammatory biomarkers and changes in T-cell subsets in individuals at PHI (n = 40), chronic HIV infection (CHI, n = 56), and HIV-uninfected (n = 58) recruited at the Manhiça District Hospital in Mozambique. Plasma levels of 49 biomarkers were determined by Luminex and ELISA. T-cell immunophenotyping was performed by multicolor flow cytometry. Plasma HIV viremia, CD4, and CD8 T cell counts underwent rapid stabilization after PHI. However, several immunological parameters, including Th1-Th17 CD4 T cells and activation or exhaustion of CD8 T cells continued decreasing until more than 9 months postinfection. Importantly, no sign of immunosenescence was observed over the first year of HIV infection. Levels of IP-10, MCP-1, BAFF, sCD14, tumor necrosis factor receptor-2, and TRAIL were significantly overexpressed at the first month of infection and underwent a prompt decrease in the subsequent months while, MIG and CD27 levels began to increase 1 month after infection and remained overexpressed for almost 1 year postinfection. Early levels of soluble biomarkers were significantly associated with subsequently exhausted CD4 T-cells or with CD8 T-cell activation. Despite rapid immune control of virus replication, the stabilization of the T-cell subsets occurs months after viremia and CD4 count plateau, suggesting persistent immune dysfunction and highlighting the potential benefit of early treatment initiation that could limit immunological damage.

Impact of antiretroviral drugs on the microbiome

Purpose of reviewLittle is known on how different antiretroviral (ARV) drugs affect the gut microbiome in HIV infection; and conflicting data exists on the effect of ARV drugs on residual inflammation/immune activation and microbial translocation.Recent findingsGut microbiome involvement in the transmission and pathogenesis of HIV infection is increasingly being recognized. Various studies have shown that antiretroviral therapy (ART) is unable to restore gut health despite effective suppression of plasma HIV viremia. Indeed, the resolution of residual inflammation and gut microbial translocation is partial under ART. Very recent studies have provided new evidence that ARV combinations can differentially affect the gut microbiome, immune activation and microbial translocation. Furthermore, a recent article uncovered a link between drug metabolism and specific microbial species indicating that microbes can directly metabolically degrade ARV drugs when administered topically.SummaryThere are still many unanswered questions regarding ARVs and the gut microbiome. It is, therefore, critical for researchers to address the effect of distinct ARV drugs on the microbiome and vice versa: the effects of the microbiome on ARV drug metabolism, and speculate about possible therapeutic avenues.

Time course of cellular HIV-DNA and low-level HIV viremia in HIV-HCVco-infected patients whose HCV infection had been successfully treated with directly acting antivirals.

This longitudinal study described cellular HIV-DNA changes and their correlation with HIV low-level plasma viremia (LLV) in HIV-HCVco-infected patients on successful antiretroviral and anti-HCV therapy by treatment with direct-acting antivirals (DAA). Thirty-nine patients were examined prior to the start of DAA (T0), after week 12 (T1) and 24weeks (T2) of anti-HCV therapy. Cellular PBMC HIV-DNA was analysed as an absolute value and as the percentage of increase or decrease from T0 to T2. Patients were classified as having undetectable plasma HIV viraemia (UV) or LLV in the year before the start of anti-HCV treatment and within the T0-T2 study period. Thirty-five patients (89.7%) of the 39 subjects enrolled had the same plasma HIV viraemia control in the year before HCV treatment and in the T0-T2 interval. The HIV-DNA value at T0 and at T2 was higher in patients with LLV than in subjects with UV (p=0.015 and p=0.014, respectively). A similar proportion of patients with LLV and UV experienced an increase or decrease of HIV-DNA from T0 to T2. The percentage increase in HIV-DNA value (262.8%) from T0 to T2 was higher compared to the decrease (43.5%) in patients with UV (p=0.012), and it was higher compared to the percentage increase in HIV-DNA value reported in subjects with LLV (262.8 versus 49%, p=0.026). HIV-HCVco-infected patients experienced a multifaceted perturbation of cellular HIV-DNA levels within a 24-week period during anti-HCV treatment; the extent of the phenomenon was greater in subjects with UV. Fast HCV-RNA clearance seemed to have a greater influence on the cellular reservoir than on plasma HIV-RNA.

FOXP3+Helios+ Regulatory T Cells, Immune Activation, and Advancing Disease in HIV-Infected Children.

Regulatory T cells (Tregs) are functionally suppressive CD4 T cells, critical for establishing peripheral tolerance and controlling inflammatory responses. Previous reports of Tregs during chronic HIV disease have conflicting results with higher or lower levels compared with controls. Identifying true Tregs with suppressive activity proves challenging during HIV infection, as traditional Treg markers, CD25 and FOXP3, may transiently upregulate expression as a result of immune activation (IA). Helios is an Ikaros family transcription factor that marks natural Tregs with suppressive activity and does not upregulate expression after activation. Coexpression of FOXP3 and Helios has been suggested as a highly specific marker of "bona fide" Tregs. We evaluated Treg subsets by FOXP3 coexpressed with either CD25 or Helios and their association with HIV disease progression in perinatally infected HIV-positive children. Identifying Tregs by FOXP3 coexpression with Helios rather than CD25 revealed markedly higher Treg frequencies, particularly in HIV+ children. Regardless of antiretroviral therapy, HIV-infected children had a selective expansion of memory FOXP3+Helios+ Tregs. The rise in memory Tregs correlated with declining HIV clinical status, indicated by falling CD4 percentages and CD4:CD8 ratios and increasing HIV plasma viremia and IA. In addition, untreated HIV+ children exhibited an imbalance between the levels of Tregs and activated T cells. Finally, memory Tregs expressed IA markers CD38 and Ki67 and exhaustion marker, PD-1, that tightly correlated with a similar phenotype in memory CD4 T cells. Overall, HIV-infected children had significant disruptions of memory Tregs that associated with advancing HIV disease.