Miguel Genebat

Long-Term Suppressive Combined Antiretroviral Treatment Does Not Normalize the Serum Level of Soluble CD14

Levels of soluble CD14 (sCD14) were longitudinally measured in 85 human immunodeficiency virus (HIV)-infected subjects during long-term receipt of suppressive combined antiretroviral therapy (cART) and compared to those in young and elderly HIV-negative control subjects. cART did not normalize sCD14 levels; rather, the HIV-infected group displayed a significantly higher sCD14 level at baseline (ie, before cART initiation), 1 year after cART initiation, and 5 years after cART initiation, compared with both control groups. Furthermore, the baseline CD4(+) T-cell count was inversely associated with the baseline sCD14 level. Our results point to the necessity of complementary therapies to treat the activated/inflamed status associated with chronic HIV infection and to the benefits of early initiation of cART.

Correlation between the Trofile® test and virological response to a short-term maraviroc exposure in HIV-infected patients

OBJECTIVES The current validated assay to determine tropism of HIV variants is Trofile, which has some limitations. The aim of this work was to correlate the virological response to a short-term maraviroc exposure with Trofile. METHODS From 1 July 2008 to 1 March 2009, 34 consecutive HIV-infected patients with detectable viral load during the last 6 months began an 8 day exposure to maraviroc (MCT group); six HIV-infected patients without antiretroviral therapy received no treatment (control group). Plasma viral load was evaluated on days 0, 2, 5 and 8. Baseline Trofile was performed in MCT group patients. The maraviroc clinical test (MCT) was considered positive if viral load was undetectable (< 40 HIV-RNA copies/mL) or a reduction > or = 1 log(10) HIV-RNA copies/mL was achieved after 8 days of maraviroc exposure. RESULTS Global concordance between MCT and Trofile was 93.5%. In patients with R5 virus according to Trofile, MCT was positive in 19/20 (concordance 95%); in patients with dual/mixed virus, MCT was negative in 10/11 (concordance 90.9%). An additional phenotypic tropism assay was performed in patients with discordance between MCT and Trofile, being concordant with MCT in both cases. Three patients showed a non-reportable Trofile result, and all of them achieved undetectability after MCT. CONCLUSIONS A clinical approach like short-term maraviroc exposure could be an additional resource to genetic and phenotypic HIV tropism assays. This clinical approach shows high concordance with Trofile, and could allow patients with non-reportable results by Trofile to benefit from maraviroc therapy.

The TLR4 ASP299GLY polymorphism is a risk factor for active tuberculosis in Caucasian HIV-infected patients.

INTRODUCTION Tuberculosis (TB) is a pandemic infectious disease especially frequent in HIV-infected patients. Toll-like receptor (TLR) 4 has been described to play a main role in the innate immunity against TB. In fact, single nucleotide polymorphisms (SNPs) in TLRs may influence AIDS disease progression. The association between two particular SNPs in human TLR4 (Asp299Gly and Thr399Ile) and active TB has been studied in non-HIV Africans with contradictory results. However, studies focusing on the effect of these TLR4 SNPs in active TB within a Caucasian HIV population are lacking. OBJECTIVES To analyze the association between TLR4 Asp299Gly and Thr399Ile SNPs and active TB, in Caucasian Mediterranean HIV-infected individuals. METHODS 468 HIV-infected patients were analyzed. TLR4 genotyping was performed by real-time PCR and melting curve technology. RESULTS TB was diagnosed in 59 (12,6%) patients. In a bivariate analysis several variables resulted significantly associated with active TB; intravenous drugs use (OR= 2.2; 95% CI [1.2-3.8]), hepatitis C virus (HCV) co-infection (OR= 3.4; 95% CI [1.6-7.1]), CD4 count (p<0.001), HIV viral load (p=0.003), latent TB prophylaxis (OR= 0.3; 95% CI [0.1-0.5]), and TLR4 Asp299Gly (OR= 2.0; 95% CI [1.1-4.2]). No statistical association was found for the TLR4 Thr399Ile. After a multivariate analysis, HCV co-infection (OR= 3.8; 95% CI [2.2-6.5]), baseline CD4 count (OR= 0.996; 95% CI [0.994-0.998]), TLR4 Asp299Gly (OR= 2.57; 95% CI [1.18-5.61]) were independently associated with active TB and inversely with latent TB prophylaxis (OR= 0.24; 95% CI [0.01-0.60]). CONCLUSIONS We describe an independent association between TLR4 Asp299Gly SNP and active TB in Caucasian Mediterranean HIV-infected patients.

Differential alterations of the CD4 and CD8 T cell subsets in HIV-infected patients on highly active antiretroviral therapy with low CD4 T cell restoration

OBJECTIVES This study examined the homeostatic parameters possibly related to HIV-infected patients who, despite being under suppressive highly active antiretroviral therapy (HAART), show low-level CD4 T cell repopulation (LLR). METHODS Twenty-one LLR individuals, 20 HIV-infected controls with satisfactory CD4 T cell repopulation (R) and 14 healthy subjects were studied. Markers related to activation, senescence and proliferation were analysed for both the CD4 and CD8 T cell subsets. Additionally, soluble CD14 (sCD14) and high-sensitivity C-reactive protein (hsCRP) were measured, and the CD34+ cells and the levels of interleukin-7 (IL-7) receptor were quantified. RESULTS The frequency of naive CD4 T cells from LLR patients was significantly reduced, and these cells showed increased expression of markers for activation, senescence and proliferation as compared with naive CD4 T cells from R patients. Naive CD8 T cells were also reduced when compared with those from R patients, but did not exhibit an altered phenotype. Moreover, frequencies of effector memory T cells were higher in LLR than R patients. No differences between LLR and R patients were observed for sCD14 levels, CD34+ cells and the IL-7 receptor, although LLR patients showed a tendency toward increased levels of hsCRP >2 μg/mL. CONCLUSIONS Patients with low CD4 T cell restoration under suppressive HAART show significant alterations in T cell homeostasis that do not appear to be related to a reduction in haematopoietic progenitors. sCD14 levels were not specifically altered in these patients. Our results agree with our previously proposed model of premature immunosenescence in LLR patients and further describe homeostatic features associated with poor CD4 recovery.

Reduced sTWEAK and Increased sCD163 Levels in HIV-Infected Patients: Modulation by Antiretroviral Treatment, HIV Replication and HCV Co-Infection

Background Patients infected with the human immunodeficiency virus (HIV) have an increased risk of cardiovascular disease due to increased inflammation and persistent immune activation. CD163 is a macrophage scavenger receptor that is involved in monocyte-macrophage activation in HIV-infected patients. CD163 interacts with TWEAK, a member of the TNF superfamily. Circulating levels of sTWEAK and sCD163 have been previously associated with cardiovascular disease, but no previous studies have fully analyzed their association with HIV. Objective The aim of this study was to analyze circulating levels of sTWEAK and sCD163 as well as other known markers of inflammation (hsCRP, IL-6 and sTNFRII) and endothelial dysfunction (sVCAM-1 and ADMA) in 26 patients with HIV before and after 48 weeks of antiretroviral treatment (ART) and 23 healthy subjects. Results Patients with HIV had reduced sTWEAK levels and increased sCD163, sVCAM-1, ADMA, hsCRP, IL-6 and sTNFRII plasma concentrations, as well as increased sCD163/sTWEAK ratio, compared with healthy subjects. Antiretroviral treatment significantly reduced the concentrations of sCD163, sVCAM-1, hsCRP and sTNFRII, although they remained elevated when compared with healthy subjects. Antiretroviral treatment had no effect on the concentrations of ADMA and sTWEAK, biomarkers associated with endothelial function. The use of protease inhibitors as part of antiretroviral therapy and the presence of HCV-HIV co-infection and/or active HIV replication attenuated the ART-mediated decrease in sCD163 plasma concentrations. Conclusion HIV-infected patients showed a proatherogenic profile characterized by increased inflammatory, immune-activation and endothelial-dysfunction biomarkers that partially improved after ART. HCV-HIV co-infection and/or active HIV replication enhanced immune activation despite ART.

TROCAI (Tropism Coreceptor Assay Information): a New Phenotypic Tropism Test and Its Correlation with Trofile Enhanced Sensitivity and Genotypic Approaches

ABSTRACT The only clinically validated assay available to determine HIV tropism is Trofile, an assay that possesses some limitations. Our first aim was to develop a new phenotypic tropism test (TROCAI [tropism coreceptor assay information]) and to categorize results generated by this test according to the virological response to a short-term exposure to the CCR5 receptor antagonist maraviroc (maraviroc clinical test). Our second aim was to compare TROCAI results to those obtained by Trofile enhanced sensitivity (ES) and to different genotypic algorithms. TROCAI assayed HIV tropism in 33 HIV-infected patient viral isolates obtained from a modified coculture, followed by multiple infection cycles of indicator cells. TROCAI obtained a reportable result in all patients with viral loads of >500 HIV RNA copies/ml and in 3/6 patients with <500 HIV RNA copies/ml (30/33 patients, 91.9%). Patients who responded to maraviroc had an X4-using virus proportion in indicator cell supernatant of 0 to 0.41%. Hence, we used the threshold of 0.5% to categorize TROCAI results as R5 (<0.5%) or dual/mixed (>0.5%). The concordance between TROCAI and Trofile (ES) was 22/24 (91.6%), and with genotypic approaches it was 22/26 (84.6%). TROCAI results, which were categorized in this study by the maraviroc clinical test, could be used as a test in addition to those currently used to select patients for treatment with CCR5 antagonists.

HIV infection-related premature immunosenescence: High rates of immune exhaustion after short time of infection

Premature immunosenescence has been reported in different HIV scenarios. However, how premature is the HIV-related immunosenescent phenotype is still unknown. Thus, the aim of this study was to analyze the immunosenescent status of young viraemic naive HIV-infected individuals, with less than four years from infection. To this end, replicative senescence, activation and proliferation T-cell levels were analyzed in chronically HIV-infected young individuals and both, elderly and young healthy controls. We show that young HIV-infected viraemic patients, with less than four years from infection, have early immune exhaustion leading to a premature immunosenescence comparable to healthy people 40 years elder. In addition, memory T-cell subsets showed greater alterations than elder healthy controls and, in patients with high viral loads, CD57 expression at the memory T-cell subsets was correlated with lower viral increases but higher CD4 T-cell lost during follow up.

Effect of Maraviroc on HIV Disease Progression-Related Biomarkers

ABSTRACT The potential effect of blocking the CCR5 receptor on HIV disease progression biomarkers is not well understood. We showed that an 8-day maraviroc (MVC) monotherapy clinical test (MCT) can be used in selecting patients to receive MVC-containing combined antiretroviral therapy (cART). Using this MCT model, we assessed the effect of MVC on several HIV disease progression biomarkers during the MCT (MVC-specific effect) and following short-term (12-week) cART. We compared 45 patients on MVC monotherapy with a control group of 25 patients on MVC-sparing cART. We found that MVC did not modify any biomarkers in patients that had no virological response after the MCT. MVC-specific effects in patients with virological responses included increased CD8+ T-cell activation and senescence levels, preservation of an increase in soluble CD14 (sCD14), and a decrease in D dimer levels. After 12 weeks, MVC-containing cART increased CD8+ T-cell counts and preserved CD4+ T-cell senescence levels compared with MVC-sparing cART. Moreover, there was a decrease in sCD14 levels in patients that received MVC-containing cART. In conclusion, effects compatible with CD8+ T-cell redistribution in peripheral blood were observed after MVC therapy. However, MVC was associated with a favorable profile in HIV disease progression biomarkers only in patients with a virological response. These results support a potential clinical benefit of a therapy which includes MVC in HIV-infected patients.

IL28B Single-Nucleotide Polymorphism rs12979860 Is Associated With Spontaneous HIV Control in White Subjects

The single-nucleotide polymorphism (SNP) rs12979860 near the IL28B gene has been associated with the spontaneous clearance of hepatitis C virus. We sought to determine whether this SNP could be associated with the spontaneous control of human immunodeficiency virus (HIV) infection. We studied the prevalence of the IL28B CC genotype among 53 white HIV controllers, compared with the prevalence among 389 HIV-infected noncontrollers. We found that the IL28B CC genotype was independently associated with spontaneous HIV control (odds ratio [OR], 2.669; P = .017), as were female sex (OR, 7.077; P ≤ .001) and the presence of HLA-B57 and/or B27 (OR, 3.080; P = .017). This result supports the idea that common host mechanisms are involved in the spontaneous control of these 2 chronic infections.

Discordance rates between Trofile test and short-term virological response to maraviroc.

Enhanced sensitivity Trofile (ES-Trofile) is the most frequently used technique to assay HIV tropism. A clinical approach to predict CCR5-antagonists efficacy, based on the virological response to a short-term maraviroc exposure (Maraviroc Clinical Test, MCT), has been recently reported. We compared the results of ES-Trofile with MCT in 47 HIV-infected patients, and a global discordance around 15% was observed between the phenotypic method and the clinical approach. Discordance results were mainly found in patients with an ES-Trofile reported as dual/mixed. These provocative results might have important clinical implications and should be considered in order to accurately prescribe treatment with CCR5 antagonists.