Decrease In Immune Activation Research Articles

Long-Term Trends of Coagulation Parameters in People Living With HIV Treated With Combined Antiretroviral Therapy.

Trends of coagulation parameters during long-term treatment with combination antiretroviral therapy (cART) are unclear. We followed 40 male subjects living with human immunodeficiency virus (HIV). Plasma levels of procoagulant parameters, factor VIII, von Willebrand factor and D-dimer, and anticoagulant parameter Protein S (PS), were measured before start and 3 months, 1 year, and 9 years after. Analyses were adjusted for cardiovascular risk factors (age, smoking, and hypertension) at baseline. At baseline, procoagulant parameters were markedly elevated and PS was in the lower range of normal. CD4/CD8-ratio improved during the complete follow-up period. In the first year, procoagulant parameters were decreasing, but at year 9 an increase was observed. After correction for cardiovascular risk factors, this increase was no longer present. PS remained stable during the first year and slightly increased from one to 9 years. This study indicates that decreasing immune activation by cART reverses the procoagulant state in HIV partially during the first year. These parameters increase in the long term despite an on-going decrease in immune activation. This increase might be related to established cardiovascular risk factors.

Correlation between blood telomere length and CD4+ CD8+ T-cell subsets changes 96 weeks after initiation of antiretroviral therapy in HIV-1-positive individuals.

In 31 participants who started first-line antiretroviral therapy in the NEAT 001/ANRS 143 clinical trial, we found after 96 weeks a statistically significant increase in blood telomere length (TL) of 0.04 (T/S Ratio) (p = 0.03). This increase was positively correlated with both the change in the percentage of CD4+ T-cells and with the decrease of CD38+ molecules on Central Memory CD8+ and negatively correlated with the change in the percentage of CD4+ Effector Memory cells. Increase in TL could be an expression of immune reconstitution and the associated decrease in immune activation. We acknowledge for the low statistical power due to the small sample size and the potential for false positive results due to multiple testing. Hence, further studies are needed to confirm these observations.

The effect of antiretroviral treatment on selected genes in whole blood from HIV-infected adults sensitised by Mycobacterium tuberculosis.

HIV-1 co-infection is a leading cause of susceptibility to tuberculosis (TB), with the risk of TB being increased at all stages of HIV-1 infection. Antiretroviral treatment (ART) is the most effective way to reduce the risk of TB in HIV-1 co-infected people. Studying protective, ART-induced, immune restoration in HIV-1 infected individuals sensitised by Mycobacterium tuberculosis (Mtb) can thus help identify mechanisms of protection against TB. In order to understand ART-mediated prevention of TB in HIV-1 infected adults, we investigated the expression of 30 genes in whole blood from HIV-1 infected patients during the first 6 months of ART-induced immune reconstitution. The 30 selected genes were previously described to be differentially expressed between sorted Mtb specific central and effector memory CD4 T cells. HIV-1 infected persons sensitised by Mtb were recruited in Khayelitsha, South Africa, when initiating ART. RNA was extracted from whole blood at initiation and 1, 3 and 6 months of ART. qRT-PCR was used to determine gene expression and three reference ‘housekeeping’ genes were used to calculate the fold change in the expression of each gene relative to day 0 of ART. Results were assessed longitudinally. We observed a decrease in the expression of a number of genes at 6 months of ART, reflecting a decrease in immune activation. However, following correction for multiple comparisons and increasing CD4 counts, only the decrease in CD27 gene expression remained statistically significant. While not statistically significant, a number of genes also showed increased expression at various timepoints, illustrating the broad regeneration of the T cell pool in HIV-1 infected adults on ART. Our findings generate hypotheses underlying ART- induced protective immune reconstitution and may pave the way for future studies to evaluate ART mediated prevention of TB in HIV-1 infected persons.

560. Immune Recovery of Acute HIV-Treated Patients Is Characterized by an Increase in Immune Senescence

BackgroundARV treatment (ART) administered during acute HIV-infection presents several immunological benefits leading to a better CD4+ T-cell recovery and a diminished HIV reservoir.MethodsPatients with acute HIV-infection, enrolled in the VIHIA cohort, had blood samples taken at diagnosis and at 2, 6 and 12 months after ART initiation. Flow-cytometry analysis was performed in fresh whole blood. Naïve-(Nv), central memory (CM), effector memory (EM) and terminally differentiated T-cells (TMRA), as well as activation markers were defined using CD3, CD4, CD8, CD45RA, CCR7, CD38, CD31 and HLA-DR markers. CD28 and CD57 were used to identify immunosenescent cells. Fox-P3, CD 25, CD127 and CD45RA were used to identify Regulatory T cells (Treg) and their subsets. To assess changes over time, Wilcoxon-matched-pairs signed rank test was used for each value between baseline and months 2 and 12 independently.ResultsFour patients were diagnosed at Fiebig stage II; 5 patients at Fiebig stage III, 24 patients at stage IV and 5 patients in stage V. All patients received treatment within the first 24 hours of HIV diagnosis. Only 13 patients had flow-cytometry data at baseline and 1 year of follow-up. All subjects were MSM with a mean age of 32 y.o. Mean CD4+ T-cell count was 439 cells/μL and mean viral load was 1.2 million copies/mL (23,379–10 × 106 copies/mL) at baseline. The change in T-cell differentiation patterns at 0 and 12 months is shown in Figure 1. Activation markers decreased in all studied subsets at 2 months and furthermore at 12 months. Total T-regs increased from 5.1% to 7.8% at 1 year of follow-up (Figure 2). Immunosenescence markers increased steadily throughout the study in all T-cell subsets, being statistically significant in the total T-cell CD8 population at 12 months of follow-up (Figure 3) unrelated to Fiebig stage.ConclusionIt has been hypothesized that early ART decreases T-cell immunosenescence; however, in our cohort despite treatment during acute HIV, we observed that at 1 year follow-up immunosenescence markers increased despite a decrease in immune activation and a recovery of T-cell subsets. Disclosures All authors: No reported disclosures.

A common anti-cytomegalovirus drug, ganciclovir, inhibits HIV-1 replication in human tissues ex vivo.

Cytomegalovirus (CMV) is a common HIV-1 copathogen. Since CMV infection is an important contributor to immune activation, the driving force of HIV disease, an anti-CMV strategy might be beneficial to HIV-infected patients. Shin et al. (J Acquir Immune Defic Syndr 2014; 65:251-258) reported that anti-CMV therapy with valganciclovir in coinfected individuals results in a decrease of HIV viral load that is not accompanied by a decrease of immune activation. This suggests an alternative mechanism for HIV inhibition other than suppression of CMV-mediated inflammation. We evaluated the anti-HIV activity of ganciclovir (GCV), the active form of valganciclovir, on HIV replication in human tissues ex vivo. We show that GCV has a direct suppressive activity on HIV replication in human tissues ex vivo, including laboratory strains, drug-resistant and primate HIV-1 isolates. We deciphered the mechanism of this inhibition and showed that GCV-TP is incorporated in the nascent DNA chain and acts as a delayed chain terminator. Our results suggest that anti-CMV strategy using valganciclovir in HIV-1-infected individuals may reduce HIV-1 viral load not only indirectly by decreasing CMV-mediated immune activation but also directly by inhibiting HIV-1 reverse transcriptase.

Lack of Difference between the Reduced Dose and Full-Dose of Antiretroviral Therapy in Terms of the Decrease in Immune Activation

Virological and immunological effectiveness of reduced doses of antiretrovirals has been shown in two randomized trials and smaller studies. We have now evaluated immune activation in patients on reduced doses of antiretroviral therapy (ART) using HLA-DR+CD8+ lymphocytes as a marker of activation.

Transient Increase of Interferon-Stimulated Genes and No Clinical Benefit by Chloroquine Treatment During Acute Simian Immunodeficiency Virus Infection of Macaques

Simian immunodeficiency virus (SIV) infection leads to AIDS in experimentally infected Rhesus macaques similarly to HIV-infected humans. In contrast, SIV infection of natural hosts is characterized by a down-regulation of innate acute responses to the virus within a few weeks of infection and results in limited pathology. Chloroquine (CQ) has been used in the treatment or prevention of malaria and has recently been shown to cause a decrease of immune activation and CD4 cell loss in HIV-infected individuals treated with antiretroviral therapy. Here, we treated Rhesus macaques with CQ during the acute phase of SIVmac251 infection with the intent to decrease viral-induced immune activation and possibly limit disease progression. Contrary to what was expected, CQ treatment resulted in a temporary increased expression of interferon (IFN)-stimulating genes and it worsened the recovery of CD4(+) T cells in the blood. Our findings confirm recent results observed in asymptomatic HIV-infected patients and suggest that CQ does not provide an obvious benefit in the absence of antiretroviral therapy.

Relationship between Regulatory T Cells and Immune Activation in Human Immunodeficiency Virus-Infected Patients Interrupting Antiretroviral Therapy

Persistent immune activation plays a central role in driving Human Immunodeficiency Virus (HIV) disease progression. Whether CD4+CD25+ regulatory T cells (Tregs) are harmful by suppressing HIV-specific immune responses and/or beneficial through a decrease in immune activation remains debatable. We analysed the relationship between proportion and number of regulatory T cells (Tregs) and immune activation in HIV-infected patients interrupting an effective antiretroviral therapy (ART). Twenty-five patients were included in a substudy of a prospective multicenter trial of treatment interruption (TI) (ANRS 116). Proportions and numbers of Tregs and the proportion of activated CD4 and CD8 T cells were assessed at baseline and month 12 (M12) of TI. Specific anti-HIV CD4 and CD8 responses were investigated at baseline and M12. Non parametric univariate analyses and multivariate linear regression models were conducted. At baseline, the proportion of Tregs negatively correlated with the proportion of HLA-DR+CD8+T cells (r = −0.519). Following TI, the proportion of Tregs increased from 6.3% to 7.2% (p = 0.029); absolute numbers of Tregs decreased. The increase in the proportion of HLA-DR+CD38+CD8+T cells was significantly related to the increase in proportion of Tregs (p = 0.031). At M12, the proportion of Tregs did not negatively correlate with CD8 T-cell activation. Nevertheless, Tregs retain a suppressive function since depletion of Treg-containing CD4+CD25+ cells led to an increase in lymphoproliferative responses in most patients studied. Our data suggest that Tregs are efficient in controlling residual immune activation in patients with ART-mediated viral suppression. However, the insufficient increase in the proportion and/or the decrease in the absolute number of Tregs result in a failure to control immune activation following TI.Trial RegistrationClinicalTrials.gov NCT00118677

T Cell Dynamics and the Response to HAART in a Cohort of HIV‐1–Infected Elite Suppressors

Elite controllers or suppressors are untreated human immunodeficiency virus type 1 (HIV-1)-infected patients who maintain undetectable viral loads. In this study, we show that most elite suppressors do not experience significant changes in T cell counts over a 10-year period. Interestingly, treatment of an elite suppressor with highly active antiretroviral therapy (HAART) led to a marked decrease in immune activation.

Predictors of Virological Outcome and Safety in Primary HIV Type 1-Infected Patients Initiating Quadruple Antiretroviral Therapy: QUEST GW PROB3005

Initiation of antiretroviral therapy during primary human immunodeficiency virus (HIV)-1 infection may confer long-term benefit. After initiation of zidovudine, lamivudine, abacavir, and amprenavir therapy in patients in the QUEST cohort, predictors of virological outcome, virological and immunological changes, and adverse events were evaluated over 48 weeks. One hundred forty-eight patients started antiretroviral therapy during primary HIV-1 infection with < or =3 bands on Western Blot (median plasma HIV-1 RNA load, 5.4 log copies/mL; median CD4 cell count, 517 cells/mm(3)). By week 48, 36% of patients had stopped treatment or were lost to follow-up. Among the 115 patients receiving follow-up care at week 48 (102 of whom were receiving antiretroviral therapy), the median viral load decrease was -5.4 log copies/mL (interquartile range [IQR], -6.4 to -3.9 log copies/mL), and the median increase in CD4 cell count was 147 cells/mm(3) (IQR, -1 to 283 cells/mm(3)); 84.2% of patients had a viral load < or =50 copies/mL, and 44.7% of patients had a viral load < or =3 copies/mL. The median cell-associated RNA level decreased from 3.4 log copies/million PBMCs (IQR, 2.9-4.1 log copies/million PBMCs) to 0.8 log copies/million PBMCs (IQR, 0.5-1.4 log copies/million PBMCs), and the median cell-associated DNA level decreased from 2.8 log copies/million PBMCs (IQR, 2.4-3.0 log copies/million PBMCs) to 1.6 log copies/million PBMCs (IQR, 1.2-1.9 log copies/million PBMCs); 33.3% of patients had an undetectable RNA level, and 9.5% of patients had an undetectable cell-associated DNA level. The median CD8(+)/CD38(++) T cell count decreased from 459 cells/mm(3) (IQR, 208-974 cells/mm(3)) to 33 cells/mm(3) (IQR, 19-75 cells/mm(3)). Baseline CD8(+)/CD38(++) T cell count and cell-associated DNA level were independent inverse predictors for reaching a viral load < or =3 copies/mL. Eighty-three patients experienced a serious adverse event (median duration of an adverse event, 15 days).Conclusions. Initiation of antiretroviral therapy during primary HIV-1 infection was associated with very significant antiretroviral activity and a decrease in immune activation. Lower baseline CD8(+)/CD38(++) T cell count and cell-associated DNA level were predictive of achieving a viral load < or =3 copies/mL.

Biventricular versus right ventricular pacing decreases immune activation and augments nitric oxide production in patients with chronic heart failure

Immune system activation and oxidative stress are involved in the pathogenesis of heart failure (HF). We aimed to test the hypothesis that upgrading from right ventricular pacing (RVp) to biventricular pacing (BiVp) can counteract these phenomena. 28 HF patients, with BiVp were switched to RVp for one week, and then returned to BiVp. Immediately prior to, and 48 h after the return to BiVp, left ventricular (LV) systolic function was evaluated by echocardiography, and serum N-terminal pro-brain natriuretic peptide (NTproBNP), C-reactive protein (CRP), tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL6), nitric oxide metabolites (NO(x)) and malondialdehyde (MDA) were assayed. LV systolic function significantly improved 48 h after switching from RVp to BiVp: Ao-VTI (p<0.001), SV (p<0.001) and CO (p<0.001), and mitral regurgitation significantly decreased (p=0.003). At the same time, indices of peripheral immune activation decreased: TNF-alpha (p=0.02) and IL6 (p<0.001). MDA decreased (p<0.001), whereas NO(x) increased (p=0.04). NTproBNP and CRP did not change. In addition, in "responders" (i.e. CO increase >10% during BiVp vs. RVp) NTproBNP decreased and NO(x) increased. However, during BiVp, the decreases in TNF-alpha, IL6, and MDA occurred both in responders and in non-responders and were accompanied by a reduction in mitral regurgitation. The beneficial effect of BiVp compared to RVp extends beyond improving cardiac haemodynamics and comprises a decrease in immune activation accompanied by an increase in serum NO(x) and decrease in serum MDA.

Increase of haemoglobin levels by anti-retroviral therapy is associated with a decrease in immune activation.

We evaluated whether an increase in haemoglobin levels in the first 6 months of effective anti-retroviral therapy (ART) is associated with a decrease in immune activation. To reduce confounding factors only men (n = 35) and patients not receiving agents known to enhance haematopoiesis or patients without diseases that might suppress haematopoiesis were included. Simultaneously parameters of iron metabolism and cofactors for haematopoiesis were analysed. A median baseline haemoglobin level of 139 g L-1 increased to 149 g L-1 at month 6 of ART (P < 0.001). At baseline low haemoglobin levels were strongly associated with high neopterin concentrations (r = - 0.64, P < 0.001), and much less correlated to high HIV-1 RNA levels (r = - 0.41, P < 0.05) and to a lower CD4+ cell count (r = 0.33, P < 0.05). The change of neopterin levels during the study period correlated with the relative change in haemoglobin levels, r = - 0.35, P = 0.03, whereas no such correlations were found for the change of HIV-1 RNA levels and the CD4 cell count. A logistic regression analysis revealed that the change of neopterin and soluble transferrin receptors concentrations are independently associated with an increase of haemoglobin levels of more than 15 g L-1. Our study supports a cause-effect relationship between immune activation and anaemia in HIV-infected patients. Treatment of patients with ART decreases virus load, which may thereby result in silencing of immune effector activity thus ameliorating anaemia by reversing the anti-proliferative effects of cytokines towards erythroid progenitors and the iron withdrawal strategy of the immune system.