Javier Martinez-Picado

IrsiCaixa Institute for AIDS Research, Badalona, Catalonia, Spain

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Publications (138)829.38 Total impact

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    ABSTRACT: Dendritic cells (DCs) are essential in order to combat invading viruses and trigger antiviral responses. Paradoxically, in the case of HIV-1, DCs might contribute to viral pathogenesis through trans-infection, a mechanism that promotes viral capture and transmission to target cells, especially after DC maturation. In this review, we highlight recent evidence identifying sialyllactose-containing gangliosides in the viral membrane and the cellular lectin Siglec-1 as critical determinants for HIV-1 capture and storage by mature DCs and for DC-mediated trans-infection of T cells. In contrast, DC-SIGN, long considered to be the main receptor for DC capture of HIV-1, plays a minor role in mature DC-mediated HIV-1 capture and trans-infection.
    PLoS Pathogens 07/2014; 10(7):e1004146. · 8.14 Impact Factor
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    ABSTRACT: Initiation of antiretroviral therapy during the earliest stages of HIV-1 infection may limit the seeding of a long-lasting viral reservoir, but long-term effects of early antiretroviral treatment initiation remain unknown. Here, we analyzed immunological and virological characteristics of nine patients who started antiretroviral therapy in primary HIV-1 infection and remained on suppressive treatment for >10 years; patients with similar treatment duration but initiation of suppressive therapy in chronic HIV-1 infection served as controls. We observed that independently of the timing of treatment initiation, HIV-1 DNA in CD4 T cells decayed primarily during the initial 3-4 years of treatment. However, in patients who started antiretroviral therapy in early infection, this decay occurred faster and was more pronounced, leading to substantially lower levels of cell-associated HIV-1 DNA after long-term treatment. Despite this smaller size, the viral CD4 T cell reservoir in persons with early treatment initiation consisted more dominantly of the long-lasting central-memory and T memory stem cells. HIV-1-specific T cell responses remained continuously detectable during antiretroviral therapy, independently of the timing of treatment initiation. Together, these data suggest that early HIV-1 treatment initiation, even when continued for >10 years, is unlikely to lead to viral eradication, but the presence of low viral reservoirs and durable HIV-1 T cell responses may make such patients attractive candidates for future interventional studies aiming at HIV-1 eradication and cure.
    Journal of virology. 06/2014;
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    ABSTRACT: OBJECTIVE:: The study of HIV-1 rapid progressors has been limited to specific case reports. Nevertheless, identification and characterization of the viral and host factors involved in rapid progression are crucial when attempting to uncover the correlates of rapid disease outcome. DESIGN:: We carried out comparative functional analyses in rapid progressors (n = 46) and standard progressors (n = 46) early after HIV-1 seroconversion (≤1 year). The viral traits tested were viral replicative capacity, co-receptor usage, and genomic variation. Host CD8 T-cell responses, humoral activity, and HLA immunogenetic markers were also determined. RESULTS:: Our data demonstrate an unusual convergence of highly pathogenic HIV-1 strains in rapid progressors. Compared with standard progressors, rapid progressor viral strains show higher in-vitro replicative capacity (81.5 vs. 67.9%; P = 0.025) and greater X4/DM co-receptor usage (26.3 vs. 2.8%; P = 0.006) in early infection. Limited or absent functional HIV-1 CD8 T-cell responses and neutralizing activity were measured in rapid progressors. Moreover, the increase in common HLA allele-restricted CD8 T-cell escape mutations in rapid progressors acts as a signature of uncontrolled HIV-1 replication and early impairment of adaptive cellular responses. CONCLUSION:: Our data support a dominant role for viral factors in rapid progressors. Robust HIV-1 replication and intrinsic viral properties limit host adaptive immune responses, thus driving rapid disease progression.
    AIDS 04/2014; · 6.41 Impact Factor
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    ABSTRACT: The study of HIV-1 rapid progressors has been limited to specific case reports. Nevertheless, identification and characterization of the viral and host factors involved in rapid progression are crucial when attempting to uncover the correlates of rapid disease outcome. We carried out comparative functional analyses in rapid progressors (n = 46) and standard progressors (n = 46) early after HIV-1 seroconversion (≤1 year). The viral traits tested were viral replicative capacity, co-receptor usage, and genomic variation. Host CD8 T-cell responses, humoral activity, and HLA immunogenetic markers were also determined. Our data demonstrate an unusual convergence of highly pathogenic HIV-1 strains in rapid progressors. Compared with standard progressors, rapid progressor viral strains show higher in-vitro replicative capacity (81.5 vs. 67.9%; P = 0.025) and greater X4/DM co-receptor usage (26.3 vs. 2.8%; P = 0.006) in early infection. Limited or absent functional HIV-1 CD8 T-cell responses and neutralizing activity were measured in rapid progressors. Moreover, the increase in common HLA allele-restricted CD8 T-cell escape mutations in rapid progressors acts as a signature of uncontrolled HIV-1 replication and early impairment of adaptive cellular responses. Our data support a dominant role for viral factors in rapid progressors. Robust HIV-1 replication and intrinsic viral properties limit host adaptive immune responses, thus driving rapid disease progression.
    AIDS (London, England) 04/2014; · 4.91 Impact Factor
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    ABSTRACT: BACKGROUND:: Latent HIV-1-infected cells generated early in the infection are responsible for viral persistence, and we hypothesized that addition of maraviroc to triple therapy in patients recently infected with HIV-1 could accelerate decay of the viral reservoir.METHODS:: Patients recently infected (<24 weeks) by chemokine receptor 5 (CCR5)-using HIV-1 were randomized to a raltegravir + tenofovir/emtricitabine regimen (control arm, n = 15) or the same regimen intensified with maraviroc (+MVC arm, n = 15). Plasma viral load, cell-associated HIV-1 DNA (total, integrated, and episomal), and activation/inflammation markers were measured longitudinally.RESULTS:: Plasma viral load decayed in both groups, reaching similar residual levels at week 48. Total cell-associated HIV-1 DNA also decreased in both groups during the first month, although subsequently at a slightly faster rate in the +MVC arm. The transient increase in two long terminal repeat (2-LTR) circles observed in both groups early after initiation of treatment decreased earlier in MVC-treated individuals. Early (week 12) increase of CD4 T-cell counts was higher in the +MVC arm. Conversely, CD8 T-cell counts and CD4 T-cell activation decreased slower in the +MVC arm. Absolute CD4 T-cell and CD8 T-cell counts, immune activation, CD4/CD8 T-cell ratio, and soluble inflammation markers were similar in both arms at the end of the study.CONCLUSION:: Addition of maraviroc in early integrase inhibitor-based treatment of HIV-1 infection results in faster reduction of 2-LTR newly infected cells and recovery of CD4 T-cell counts, and a modest reduction in total reservoir size after 48 weeks of treatment. Paradoxically, CCR5 blockade also induced a slower decrease in plasma viremia and immune activation
    AIDS 01/2014; 28:325-34. · 6.41 Impact Factor
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    ABSTRACT: BACKGROUND: The effect of maraviroc on the maintenance and the function of HIV-1-specific T cell responses remains unknown.METHODS: Subjects recently infected with HIV-1 were randomized to receive anti-retroviral treatment with or without maraviroc intensification for 48 weeks, and were monitored up to week 60. PBMC and in vitro-expanded T cells were tested for responses to the entire HIV proteome by ELISpot analyses. Intracellular cytokine staining assays were conducted to monitor the (poly)-functionality of HIV-1-specific T cells. Analyses were performed at baseline and week 24 after treatment start, and at week 60 (3 months after maraviroc discontinuation).RESULTS: Maraviroc intensification was associated with a slower decay of virus-specific T cell responses over time compared to the non-intensified regimen in both direct ex-vivo as well as in in-vitro expanded cells. The effector function profiles of virus-specific CD8(+) T cells were indistinguishable between the two arms and did not change over time between the groups.CONCLUSIONS: Maraviroc did not negatively impact any of the measured parameters, but was rather associated with a prolonged maintenance of HIV-1-specific T cell responses. Maraviroc, in addition to its original effect as viral entry inhibitor, may provide an additional benefit on the maintenance of virus-specific T cells which may be especially important for future viral eradication strategies
    PLoS ONE 01/2014; 9(1):e87334. · 3.53 Impact Factor
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    ABSTRACT: HIV-1 contact with target cells triggers F-actin rearrangements that are essential for several steps of the viral cycle. Successful HIV entry into CD4+ T cells requires actin reorganization induced by interaction of the cellular receptor/co-receptor complex CD4/CXCR4 with the viral envelope complex gp120/gp41 (Env). In this report, we analyze the role of the actin modulator drebrin in HIV-1 viral infection and cell-to-cell fusion. We show that drebrin associates with CXCR4 before and during HIV infection. Drebrin is actively recruited toward cell-virus and Env-driven cell-to-cell contacts. After viral internalization, drebrin clustering is retained in a fraction of the internalized particles. Through a combination of RNAi-based inhibition of endogenous drebrin and GFP-tagged expression of wild-type and mutant forms, we establish drebrin as a negative regulator of HIV entry and HIV-mediated cell fusion. Down-regulation of drebrin expression promotes HIV-1 entry, decreases F-actin polymerization and enhances profilin local accumulation in response to HIV-1. These data underscore the negative role of drebrin in HIV infection by modulating viral entry, mainly through the control of actin cytoskeleton polymerization in response to HIV-1.
    Journal of Biological Chemistry 08/2013; · 4.65 Impact Factor
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    ABSTRACT: Multiple genome-wide association studies (GWAS) have been performed in HIV-1 infected individuals, identifying common genetic influences on viral control and disease course. Similarly, common genetic correlates of acquisition of HIV-1 after exposure have been interrogated using GWAS, although in generally small samples. Under the auspices of the International Collaboration for the Genomics of HIV, we have combined the genome-wide single nucleotide polymorphism (SNP) data collected by 25 cohorts, studies, or institutions on HIV-1 infected individuals and compared them to carefully matched population-level data sets (a list of all collaborators appears in Note S1 in Text S1). After imputation using the 1,000 Genomes Project reference panel, we tested approximately 8 million common DNA variants (SNPs and indels) for association with HIV-1 acquisition in 6,334 infected patients and 7,247 population samples of European ancestry. Initial association testing identified the SNP rs4418214, the C allele of which is known to tag the HLA-B*57:01 and B*27:05 alleles, as genome-wide significant (p = 3.6×10−11). However, restricting analysis to individuals with a known date of seroconversion suggested that this association was due to the frailty bias in studies of lethal diseases. Further analyses including testing recessive genetic models, testing for bulk effects of non-genome-wide significant variants, stratifying by sexual or parenteral transmission risk and testing previously reported associations showed no evidence for genetic influence on HIV-1 acquisition (with the exception of CCR5Δ32 homozygosity). Thus, these data suggest that genetic influences on HIV acquisition are either rare or have smaller effects than can be detected by this sample size.
    PLoS Pathogens 07/2013; 9(7):e1003515. · 8.14 Impact Factor
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    ABSTRACT: BACKGROUND: Immune hyperactivation in immunodiscordant patients can induce residual HIV replication and limit CD4 T cell recovery. We assessed the impact of raltegravir intensification on CD4 T cell recovery and viral persistence. METHODS: We performed a randomized, controlled, pilot trial. Patients with CD4 T cell counts <350 cells/mm(3) despite suppressive antiretroviral therapy were randomized (2 : 1) to intensify with raltegravir (intensified arm, n = 30) or to continue with the same regimen (control arm, n = 14) for 48 weeks. Then, the control individuals intensified their treatment for 24 weeks (delayed-intensification arm). We analysed changes in CD4 T cell counts, total and episomal HIV DNA in peripheral blood mononuclear cells and predictive factors for response. RESULTS: Raltegravir intensification induced a rapid increase in CD4 T cell counts (week 12) (P = 0.007), although this was not sustained over time. Control patients maintained constant but slow increases in CD4 T cell counts (present in the pre-study period), reaching CD4 T cell counts similar to those of patients in the intensification arm at week 48. This effect was confirmed by the analysis of the delayed-intensification arm. Proviral DNA levels remained stable in both arms over time; episomal DNA forms and ultrasensitive plasma viral load were barely detected during the study. Increases in CD4 T cell counts were associated with low baseline CD95 expression in CD4 and CD8 T cells (P = 0.020). CONCLUSIONS: Raltegravir intensification modestly impacts viral dynamics and induces a rapid but limited gain in CD4 T cell counts in immunodiscordant patients. Residual viral replication does not seem to be the main cause of unsatisfactory CD4 T cell recovery in these patients.
    Journal of Antimicrobial Chemotherapy 05/2013; · 5.34 Impact Factor
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    ABSTRACT: Increased lymphocyte death is a hallmark of human immunodeficiency virus (HIV) infection. Although virological factors have been linked to this phenomenon, increased cell death rates are still observed in treated individuals in which viral replication is halted. To understand the nature of this remaining altered cell death, we have developed a simple and fast assay to assess major cell death pathways in lymphocytes isolated from HIV-infected individuals. The combination of three factors: (i) antibody staining to identify CD3(+) CD4(+) and CD3(+) CD8(+) cells, (ii) assessment of mitochondrial and plasma membrane function using DiOC6(3) or JC-1 probes and vital dyes, and (iii) caspase inhibition, allowed for the quantification of caspase-independent and -dependent cell death in CD4 and CD8 T cells. The latter mechanism was divided in intrinsic and extrinsic apoptotic pathways according to the sensitivity of the dissipation of mitochondrial membrane potential to Z-VAD-fmk or Q-VD-oPH treatment. Our data show similar results for both caspase inhibitors in treated infected individuals, whereas Q-VD-oPH showed a more potent inhibition in viremic individuals, yielding lower levels of intrinsic apoptosis. Comparison of DiOC6(3) and JC-1 probes yielded similar results in CD4 T cells, allowing for a clear definition of death mechanism in these cells. However, in CD8 T-cells, JC-1 showed heterogeneous staining and detected significantly lower levels of cell death with a higher contribution of intrinsic apoptosis. In conclusion, we provide a simple method to assess CD4 T-cell death mechanisms in HIV-infected individuals. The reasons and consequences of mitochondrial heterogeneity in CD8 T-cells require further evaluation. © 2012 International Society for Advancement of Cytometry.
    Cytometry Part A 05/2013; · 3.71 Impact Factor
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    ABSTRACT: BACKGROUND: Since cell-mediated infection of human immunodeficiency virus type 1 (HIV-1) is more efficient than cell-free infection, cell-to-cell propagation plays a crucial role in the pathogenesis of HIV-1 infection. Transmission of HIV-1 is enabled by two types of cellular contacts, namely, virological synapses between productively infected cells and uninfected target cells and infectious synapses between uninfected dendritic cells (DC) harboring HIV-1 and uninfected target cells. While virological synapses are driven by expression of the viral envelope glycoprotein on the cell surface, little is known about the role of envelope glycoprotein during contact between DC and T cells. We explored the contribution of HIV-1 envelope glycoprotein, adhesion molecules, and antigen recognition in the formation of conjugates comprising mature DC (mDC) and CD4+ T cells in order to further evaluate their role in mDC-mediated HIV-1 transmission at the immunological synapse. RESULTS: Unlike virological synapse, HIV-1 did not modulate the formation of cell conjugates comprising mDC harboring HIV-1 and non-activated primary CD4+ T cells. Disruption of interactions between ICAM-1 and LFA-1, however, resulted in a 60% decrease in mDC-CD4+ T-cell conjugate formation and, consequently, in a significant reduction of mDC-mediated HIV-1 transmission to non-activated primary CD4+ T cells (p < 0.05). Antigen recognition or sustained MHC-TcR interaction did not enhance conjugate formation, but significantly boosted productive mDC-mediated transmission of HIV-1 (p < 0.05) by increasing T-cell activation and proliferation. CONCLUSIONS: Formation of the infectious synapse is independent of the presence of the HIV-1 envelope glycoprotein, although it does require an interaction between ICAM-1 and LFA-1. This interaction is the main driving force behind the formation of mDC-CD4+ T-cell conjugates and enables transmission of HIV-1 to CD4+ T cells. Moreover, antigen recognition boosts HIV-1 replication without affecting the frequency of cellular conjugates. Our results suggest a determinant role for immune activation driven by mDC-CD4+ T-cell contacts in viral dissemination and that this activation likely contributes to the pathogenesis of HIV-1 infection.
    Retrovirology 04/2013; 10(1):42. · 5.66 Impact Factor
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    ABSTRACT: Antiretroviral therapy for HIV infection needs lifelong access and strict adherence to regimens that are both expensive and associated with toxic effects. A curative intervention will be needed to fully stop the epidemic. The failure to eradicate HIV infection during long-term antiretroviral therapy shows the intrinsic stability of the viral genome in latently infected CD4T cells and other cells, and possibly a sustained low-level viral replication. Heterogeneity in latently infected cell populations and homoeostatic proliferation of infected cells might affect the dynamics of virus production and persistence. Despite potent antiretroviral therapy, chronic immune activation, inflammation, and immune dysfunction persist, and are likely to have important effects on the size and distribution of the viral reservoir. The inability of the immune system to recognise cells harbouring latent virus and to eliminate cells actively producing virus is the biggest challenge to finding a cure. We look at new approaches to unravelling the complex virus-host interactions that lead to persistent infection and latency, and discuss the rationale for combination of novel treatment strategies with available antiretroviral treatment options to cure HIV.
    The Lancet 03/2013; · 39.06 Impact Factor
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    ABSTRACT: BACKGROUND:: Detection of episomal HIV cDNA has been associated with greater levels of CD8 and CD4 T-cell activation in HIV-1-infected HAART-suppressed individuals. However, HAART intensification exclusively reduced CD8 T cell activation. METHODS:: We evaluated activation markers 12 weeks after raltegravir withdrawal in a previously described 48-week raltegravir-intensification study. Subjects (n=34) were subgrouped into 2-LTR (n=12) or 2-LTR (n=22) subgroups according to delectability of 2-LTR episomes during intensification period. RESULTS:: The initial differences in CD8 T-cell activation between subgroups were lost after intensification. Linear mixed models revealed significant reductions in CD8 T-cell activation in both 2-LTR and 2-LTR subgroups, suggesting that raltegravir impacts subjects irrespective of 2-LTR detection. Remarkably, a partial rebound in CD8 activation markers after raltegravir discontinuation was observed in the 2-LTR subgroup. This restored the differences between subgroups observed at study entry, particularly in terms of CD38 expression within CD8 memory T-cells. Conversely, CD4 T-cell activation remained unchanged in both subgroups during the study period, although an early and transient CD45RA CD4 T-cells redistribution from tissues was apparent. CONCLUSION:: CD8 T-cell activation undergoes reversible changes during raltegravir intensification and discontinuation in patients showing detectable 2-LTR circles. The general decrease in CD8 T-cell activation and a transient CD45RA CD4 T-cell redistribution in intensified individuals may reflect residual viral replication during apparently suppressive HAART.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 02/2013; · 4.65 Impact Factor
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    ABSTRACT: Background Human genetic variation contributes to differences in susceptibility to HIV-1 infection. To search for novel host resistance factors, we performed a genome-wide association study in hemophilia patients highly exposed to potentially contaminated factor VIII infusions.Methods Individuals with hemophilia A and a documented history of factor VIII infusions before the introduction of viral inactivation procedures (1979-1984) were recruited from 36 hemophilia treatment centers, and their genome-wide genetic variants were compared to those from matched HIV-infected individuals. Homozygous carriers of known CCR5 resistance mutations were excluded. Single nucleotide polymorphisms (SNPs) and inferred copy number variants (CNVs) were tested using logistic regression. In addition, we performed a pathway enrichment analysis, a heritability analysis, and a search for epistatic interactions with CCR5 Δ32 heterozygosity.ResultsA total of 560 HIV-uninfected cases were recruited: 36 (6.4%) were homozygous for CCR5 Δ32 or m303. After quality control and SNP imputation, we tested 1,081,435 SNPs and 3,686 CNVs for association with HIV-1 serostatus in 431 cases and 765 HIV-infected controls. No SNP or CNV reached genome-wide significance. The additional analyses did not reveal any strong genetic effect.Conclusions Highly exposed, yet uninfected hemophiliacs form an ideal study group to investigate host resistance factors. Using a genome-wide approach, we did not detect significant associations between SNPs and HIV-1 susceptibility, indicating that common genetic variants of major effect are unlikely to explain the observed resistance phenotype in this population.
    Human Molecular Genetics 01/2013; · 7.69 Impact Factor
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    ABSTRACT: Combination antiretroviral therapy (cART) greatly improves survival and quality of life of HIV-1-infected patients; however, cART must be continued indefinitely to prevent viral rebound and associated disease progression. Inducing HIV-1-specific immune responses with a therapeutic immunization has been proposed to control viral replication after discontinuation of cART as an alternative to "cART for life." We report safety, tolerability, and immunogenicity results associated with a control of viral replication for a therapeutic vaccine using autologous monocyte-derived dendritic cells (MD-DCs) pulsed with autologous heat-inactivated whole HIV. Patients on cART with CD4(+) >450 cells/mm(3) were randomized to receive three immunizations with MD-DCs or with nonpulsed MD-DCs. Vaccination was feasible, safe, and well tolerated and shifted the virus/host balance. At weeks 12 and 24 after cART interruption, a decrease of plasma viral load setpoint ≥1 log was observed in 12 of 22 (55%) versus 1 of 11 (9%) and in 7 of 20 (35%) versus 0 of 10 (0%) patients in the DC-HIV-1 and DC-control groups, respectively. This significant decrease in plasma viral load observed in immunized recipients was associated with a consistent increase in HIV-1-specific T cell responses. These data suggest that HIV-1-specific immune responses elicited by therapeutic DC vaccines could significantly change plasma viral load setpoint after cART interruption in chronic HIV-1-infected patients treated in early stages. This proof of concept supports further investigation of new candidates and/or new optimized strategies of vaccination with the final objective of obtaining a functional cure as an alternative to cART for life.
    Science translational medicine 01/2013; 5(166):166ra2. · 10.76 Impact Factor
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    ABSTRACT: Technically, HIV-1 tropism can be evaluated in plasma or peripheral blood mononuclear cells (PBMCs). However, only tropism testing of plasma HIV-1 has been validated as a tool to predict virological response to CCR5 antagonists in clinical trials. The preferable tropism testing strategy in subjects with undetectable HIV-1 viremia, in whom plasma tropism testing is not feasible, remains uncertain. We designed a proof-of-concept study including 30 chronically HIV-1-infected individuals who achieved HIV-1 RNA <50 copies/mL during at least 2 years after first-line ART initiation. First, we determined the diagnostic accuracy of 454 and population sequencing of gp120 V3-loops in plasma and PBMCs, as well as of MT-2 assays before ART initiation. The Enhanced Sensitivity Trofile Assay (ESTA) was used as the technical reference standard. 454 sequencing of plasma viruses provided the highest agreement with ESTA. The accuracy of 454 sequencing decreased in PBMCs due to reduced specificity. Population sequencing in plasma and PBMCs was slightly less accurate than plasma 454 sequencing, being less sensitive but more specific. MT-2 assays had low sensitivity but 100% specificity. Then, we used optimized 454 sequence data to investigate viral evolution in PBMCs during viremia suppression and only found evolution of R5 viruses in one subject. No de novo CXCR4-using HIV-1 production was observed over time. Finally, Slatkin-Maddison tests suggested that plasma and cell-associated V3 forms were sometimes compartmentalized. The absence of tropism shifts during viremia suppression suggests that, when available, testing of stored plasma samples is generally safe and informative, provided that HIV-1 suppression is maintained. Tropism testing in PBMCs may not necessarily produce equivalent biological results to plasma, because the structure of viral populations and the diagnostic performance of tropism assays may sometimes vary between compartments. Thereby, proviral DNA tropism testing should be specifically validated in clinical trials before it can be applied to routine clinical decision-making.
    PLoS ONE 01/2013; 8(8):e67085. · 3.53 Impact Factor
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    ABSTRACT: HIV-1 sequence diversity is affected by selection pressures arising from host genomic factors. Using paired human and viral data from 1071 individuals, we ran >3000 genome-wide scans, testing for associations between host DNA polymorphisms, HIV-1 sequence variation and plasma viral load (VL), while considering human and viral population structure. We observed significant human SNP associations to a total of 48 HIV-1 amino acid variants (p<2.4 × 10(-12)). All associated SNPs mapped to the HLA class I region. Clinical relevance of host and pathogen variation was assessed using VL results. We identified two critical advantages to the use of viral variation for identifying host factors: (1) association signals are much stronger for HIV-1 sequence variants than VL, reflecting the 'intermediate phenotype' nature of viral variation; (2) association testing can be run without any clinical data. The proposed genome-to-genome approach highlights sites of genomic conflict and is a strategy generally applicable to studies of host-pathogen interaction. DOI:http://dx.doi.org/10.7554/eLife.01123.001.
    eLife Sciences 01/2013; 2:e01123.
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    ABSTRACT: A model of reservoir activation and viral replication is introduced accounting for the production of 2-LTR HIV-1 DNA circles following antiviral intensification with the HIV integrase inhibitor raltegravir, considering contributions of de novo infection events and exogenous sources of infected cells, including quiescent infected cell activation. The model shows that a monotonic increase in measured 2-LTR concentration post intensification is consistent with limited de novo infection primarily maintained by sources of infected cells unaffected by raltegravir, such as quiescent cell activation, while a transient increase in measured 2-LTR concentration is consistent with significant levels of efficient (R0 > 1) de novo infection. The model is validated against patient data from the INTEGRAL study and is shown to have a statistically significant fit relative to the null hypothesis of random measurement variation about a mean. We obtain estimates and confidence intervals for the model parameters, including 2-LTR half-life. Seven of the 13 patients with detectable 2-LTR concentrations from the INTEGRAL study have measured 2-LTR dynamics consistent with significant levels of efficient replication of the virus prior to treatment intensification.
    Journal of The Royal Society Interface 01/2013; 10(84):20130186. · 4.91 Impact Factor
  • Marta Massanella, Javier Martinez-Picado, Julià Blanco
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    ABSTRACT: Upon HIV infection, a subset of latently infected cells carrying transcriptionally inactive integrated proviral DNA (the HIV-1 reservoir) is rapidly established. These cells are the main force behind HIV persistence under highly active antiretroviral therapy (HAART), which only impacts on actively replicating viruses and it is therefore unable to eradicate the infection. However, the case of Timothy Brown, also known as the Berlin patient, demonstrates that eradication is possible, and recent data support the idea that latency may be reverted in vivo, suggesting that it is possible to perturb the HIV-1 reservoir. This may be achieved by implementing both pharmacological and immunological strategies to reactivate HIV-1 from latently infected cells. Nevertheless, reactivation might not be sufficient to eradicate the virus. Reinforcing HIV-1-specific immune responses and blocking potential new events of viral replication will probably help reaching the final goal of eradication or the alternative objective of a functional cure for HIV-1.
    Current HIV/AIDS Reports 12/2012;

Publication Stats

5k Citations
829.38 Total Impact Points

Institutions

  • 2011–2014
    • IrsiCaixa Institute for AIDS Research
      Badalona, Catalonia, Spain
  • 2007–2014
    • Catalan Institution for Research and Advanced Studies
      Barcino, Catalonia, Spain
  • 2013
    • École Polytechnique Fédérale de Lausanne
      • Faculté des Sciences de la Vie
      Lausanne, VD, Switzerland
    • Broad Institute of MIT and Harvard
      Cambridge, Massachusetts, United States
    • Swiss Institute of Bioinformatics
      Lausanne, Vaud, Switzerland
  • 2011–2013
    • IGTP Health Sciences Research Institute of the Germans Trias i Pujol Foundation
      Badalona, Catalonia, Spain
    • University of Delaware
      • Department of Electrical and Computer Engineering
      Newark, DE, United States
  • 2008–2013
    • Institut Marqués, Spain, Barcelona
      Barcino, Catalonia, Spain
  • 1999–2013
    • Hospital Universitari Germans Trias i Pujol
      • Department of Clinical Pharmacology
      Badalona, Catalonia, Spain
  • 2012
    • University of Barcelona
      Barcino, Catalonia, Spain
  • 2004–2012
    • Spanish National Research Council
      • Centro de Biología Molecular "Severo Ochoa"
      Madrid, Madrid, Spain
  • 2003–2012
    • University of California, San Diego
      San Diego, California, United States
  • 2008–2011
    • Universidad Autónoma de Madrid
      Madrid, Madrid, Spain
  • 2010
    • Fundació Institut Investigació Germans Trias i Pujol
      Badalona, Catalonia, Spain
    • Centro De Biología Molecular Severo Ochoa
      Madrid, Madrid, Spain
  • 2009
    • Universita' degli Studi "Magna Græcia" di Catanzaro
      Catanzaro, Calabria, Italy
  • 2007–2009
    • Duke University Medical Center
      • • Center for Human Genome Variation
      • • Institute for Genome Sciences and Policy
      Durham, NC, United States
  • 2003–2009
    • Autonomous University of Barcelona
      Cerdanyola del Vallès, Catalonia, Spain
  • 2006
    • Howard Hughes Medical Institute
      Maryland, United States
  • 2002
    • The University of Edinburgh
      • Credit Research Centre
      Edinburgh, Scotland, United Kingdom
  • 2000
    • University of Alabama
      Tuscaloosa, Alabama, United States
    • Harvard University
      • Department of Biostatistics
      Cambridge, MA, United States
  • 1999–2000
    • Massachusetts General Hospital
      • Division of Infectious Diseases
      Boston, Massachusetts, United States
  • 1998
    • Harvard Medical School
      Boston, Massachusetts, United States