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1.
Cell ; 186(22): 4851-4867.e20, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37848036

RESUMEN

Post-acute sequelae of COVID-19 (PASC, "Long COVID") pose a significant global health challenge. The pathophysiology is unknown, and no effective treatments have been found to date. Several hypotheses have been formulated to explain the etiology of PASC, including viral persistence, chronic inflammation, hypercoagulability, and autonomic dysfunction. Here, we propose a mechanism that links all four hypotheses in a single pathway and provides actionable insights for therapeutic interventions. We find that PASC are associated with serotonin reduction. Viral infection and type I interferon-driven inflammation reduce serotonin through three mechanisms: diminished intestinal absorption of the serotonin precursor tryptophan; platelet hyperactivation and thrombocytopenia, which impacts serotonin storage; and enhanced MAO-mediated serotonin turnover. Peripheral serotonin reduction, in turn, impedes the activity of the vagus nerve and thereby impairs hippocampal responses and memory. These findings provide a possible explanation for neurocognitive symptoms associated with viral persistence in Long COVID, which may extend to other post-viral syndromes.


Asunto(s)
Síndrome Post Agudo de COVID-19 , Serotonina , Humanos , COVID-19/complicaciones , Progresión de la Enfermedad , Inflamación , Síndrome Post Agudo de COVID-19/sangre , Síndrome Post Agudo de COVID-19/patología , Serotonina/sangre , Virosis
3.
Blood ; 143(11): 1049-1054, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38052031

RESUMEN

ABSTRACT: We show that red cell exchange (RCE) treats hyperleukocytosis in acute leukemia. RCE provided similar leukoreduction to standard therapeutic leukoreduction and could be superior in patients with severe anemia or monocytic leukemias or when requiring rapid treatment.


Asunto(s)
Leucemia Monocítica Aguda , Leucemia Mieloide Aguda , Leucostasis , Adulto , Humanos , Leucostasis/terapia , Leucemia Mieloide Aguda/terapia , Leucemia Monocítica Aguda/terapia , Enfermedad Aguda , Leucaféresis , Leucocitosis/terapia
4.
J Virol ; 94(9)2020 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-32051279

RESUMEN

Next-generation sequencing (NGS) represents a powerful tool to unravel the genetic make-up of the HIV reservoir, but limited data exist on its use in vitro Moreover, most NGS studies do not separate integrated from unintegrated DNA, even though selection pressures on these two forms should be distinct. We reasoned we could use NGS to compare the infection of resting and activated CD4 T cells in vitro to address how the metabolic state affects reservoir formation and dynamics. To address these questions, we obtained HIV sequences 2, 4, and 8 days after NL4-3 infection of metabolically activated and quiescent CD4 T cells (cultured with 2 ng/ml interleukin-7). We compared the composition of integrated and total HIV DNA by isolating integrated HIV DNA using pulsed-field electrophoresis before performing sequencing. After a single-round infection, the majority of integrated HIV DNA was intact in both resting and activated T cells. The decay of integrated intact proviruses was rapid and similar in both quiescent and activated T cells. Defective forms accumulated relative to intact ones analogously to what is observed in vivo Massively deleted viral sequences formed more frequently in resting cells, likely due to lower deoxynucleoside triphosphate (dNTP) levels and the presence of multiple restriction factors. To our surprise, the majority of these deleted sequences did not integrate into the human genome. The use of NGS to study reservoir dynamics in vitro provides a model that recapitulates important aspects of reservoir dynamics. Moreover, separating integrated from unintegrated HIV DNA is important in some clinical settings to properly study selection pressures.IMPORTANCE The major implication of our work is that the decay of intact proviruses in vitro is extremely rapid, perhaps as a result of enhanced expression. Gaining a better understanding of why intact proviruses decay faster in vitro might help the field identify strategies to purge the reservoir in vivo When used wisely, in vitro models are a powerful tool to study the selective pressures shaping the viral landscape. Our finding that massively deleted sequences rarely succeed in integrating has several ramifications. It demonstrates that the total HIV DNA can differ substantially in character from the integrated HIV DNA under certain circumstances. The presence of unintegrated HIV DNA has the potential to obscure selection pressures and confound the interpretation of clinical studies, especially in the case of trials involving treatment interruptions.


Asunto(s)
Infecciones por VIH/genética , VIH-1/genética , Provirus/genética , Linfocitos T CD4-Positivos/inmunología , ADN Viral/genética , Reservorios de Enfermedades/virología , Infecciones por VIH/virología , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Integración Viral/genética , Latencia del Virus/genética , Replicación Viral/genética
5.
Clin Chem ; 68(1): 230-239, 2021 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-34383886

RESUMEN

BACKGROUND: High-sensitivity severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen assays are desirable to mitigate false negative results. Limited data are available to quantify and track SARS-CoV-2 antigen burden in respiratory samples from different populations. METHODS: We developed the Microbubbling SARS-CoV-2 Antigen Assay (MSAA) with smartphone readout, with a limit of detection of 0.5 pg/mL (10.6 fmol/L) nucleocapsid antigen or 4000 copies/mL inactivated SARS-CoV-2 virus in nasopharyngeal (NP) swabs. We developed a computer vision and machine learning-based automatic microbubble image classifier to accurately identify positives and negatives and quantified and tracked antigen dynamics in intensive care unit coronavirus disease 2019 (COVID-19) inpatients and immunocompromised COVID-19 patients. RESULTS: Compared to qualitative reverse transcription-polymerase chain reaction methods, the MSAA demonstrated a positive percentage agreement of 97% (95% CI 92%-99%) and a negative percentage agreement of 97% (95% CI 94%-100%) in a clinical validation study with 372 residual clinical NP swabs. In immunocompetent individuals, the antigen positivity rate in swabs decreased as days-after-symptom-onset increased, despite persistent nucleic acid positivity. Antigen was detected for longer and variable periods of time in immunocompromised patients with hematologic malignancies. Total microbubble volume, a quantitative marker of antigen burden, correlated inversely with cycle threshold values and days-after-symptom-onset. Viral sequence variations were detected in patients with long duration of high antigen burden. CONCLUSIONS: The MSAA enables sensitive and specific detection of acute infections and quantification and tracking of antigen burden and may serve as a screening method in longitudinal studies to identify patients who are likely experiencing active rounds of ongoing replication and warrant close viral sequence monitoring.


Asunto(s)
Antígenos Virales/análisis , Prueba de COVID-19/métodos , COVID-19 , Teléfono Inteligente , COVID-19/diagnóstico , Humanos , Aprendizaje Automático , SARS-CoV-2 , Sensibilidad y Especificidad
6.
PLoS Pathog ; 14(9): e1007257, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30180214

RESUMEN

HIV-1 can downregulate HLA-C on infected cells, using the viral protein Vpu, and the magnitude of this downregulation varies widely between primary HIV-1 variants. The selection pressures that result in viral downregulation of HLA-C in some individuals, but preservation of surface HLA-C in others are not clear. To better understand viral immune evasion targeting HLA-C, we have characterized HLA-C downregulation by a range of primary HIV-1 viruses. 128 replication competent viral isolates from 19 individuals with effective anti-retroviral therapy, show that a substantial minority of individuals harbor latent reservoir virus which strongly downregulates HLA-C. Untreated infections display no change in HLA-C downregulation during the first 6 months of infection, but variation between viral quasispecies can be detected in chronic infection. Vpu molecules cloned from plasma of 195 treatment naïve individuals in chronic infection demonstrate that downregulation of HLA-C adapts to host HLA genotype. HLA-C alleles differ in the pressure they exert for downregulation, and individuals with higher levels of HLA-C expression favor greater viral downregulation of HLA-C. Studies of primary and mutant molecules identify 5 residues in the transmembrane region of Vpu, and 4 residues in the transmembrane domain of HLA-C, which determine interactions between Vpu and HLA. The observed adaptation of Vpu-mediated downregulation to host genotype indicates that HLA-C alleles differ in likelihood of mediating a CTL response that is subverted by viral downregulation, and that preservation of HLA-C expression is favored in the absence of these responses. Finding that latent reservoir viruses can downregulate HLA-C could have implications for HIV-1 cure therapy approaches in some individuals.


Asunto(s)
Infecciones por VIH/genética , Infecciones por VIH/inmunología , VIH-1/patogenicidad , Antígenos HLA-C/genética , Secuencia de Aminoácidos , Reservorios de Enfermedades/virología , Regulación hacia Abajo , Variación Genética , Genotipo , Infecciones por VIH/virología , VIH-1/inmunología , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Proteínas del Virus de la Inmunodeficiencia Humana/química , Proteínas del Virus de la Inmunodeficiencia Humana/genética , Proteínas del Virus de la Inmunodeficiencia Humana/inmunología , Humanos , Evasión Inmune , Proteínas Reguladoras y Accesorias Virales/química , Proteínas Reguladoras y Accesorias Virales/genética , Proteínas Reguladoras y Accesorias Virales/inmunología
7.
J Virol ; 92(12)2018 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-29593048

RESUMEN

Analytic treatment interruption (ATI) studies are required to evaluate strategies aimed at achieving ART-free HIV remission, but the impact of ATI on the viral reservoir remains unclear. We validated a DNA size selection-based assay for measuring levels of integrated HIV DNA and applied it to assess the effects of short-term ATI on the HIV reservoir. Samples from participants from four AIDS Clinical Trials Group ATI studies were assayed for integrated HIV DNA levels. Cryopreserved peripheral blood mononuclear cells (PBMCs) were obtained for 12 participants with available samples pre-ATI and approximately 6 months after ART resumption. Four participants also had samples available during the ATI. The median duration of ATI was 12 weeks. Validation of the HIV integrated DNA size-exclusion (HIDE) assay was performed using samples spiked with unintegrated HIV DNA, HIV-infected cell lines, and participant PBMCs. The HIDE assay eliminated 99% of unintegrated HIV DNA species and strongly correlated with the established Alu-gag assay. For the majority of individuals, integrated DNA levels increased during ATI and subsequently declined upon ART resumption. There was no significant difference in the levels of integrated HIV DNA between the pre- and post-ATI time points, with a median ratio of post- to pre-ATI HIV DNA levels of 0.95. Using a new integrated HIV DNA assay, we found minimal change in the levels of integrated HIV DNA in participants who underwent an ATI, followed by 6 months of ART. This suggests that short-term ATI can be conducted without a significant impact on the levels of integrated proviral DNA in the peripheral blood.IMPORTANCE Interventions aimed at achieving sustained antiretroviral therapy (ART)-free HIV remission require treatment interruption trials to assess their efficacy. However, these trials are accompanied by safety concerns related to the expansion of the viral reservoir. We validated an assay that uses an automated DNA size-selection platform for quantifying levels of integrated HIV DNA and is less sample- and labor-intensive than current assays. Using stored samples from AIDS Clinical Trials Group studies, we found that short-term ART discontinuation had minimal impact on integrated HIV DNA levels after ART resumption, providing reassurance about the reservoir effects of short-term treatment interruption trials.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , ADN Viral/genética , Infecciones por VIH/virología , Carga Viral/genética , Integración Viral/genética , VIH-1/genética , Humanos , Leucocitos Mononucleares/virología , Provirus/genética , Carga Viral/efectos de los fármacos , Privación de Tratamiento
8.
J Virol ; 92(13)2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29643240

RESUMEN

HIV protease is known to cause cell death, which is dependent upon cleavage of procaspase 8. HIV protease cleavage of procaspase 8 generates Casp8p41, which directly binds Bak with nanomolar affinity, causing Bak activation and consequent cell death. Casp8p41 can also bind Bcl2 with nanomolar affinity, in which case cell death is averted. Central memory CD4 T cells express high levels of Bcl2, possibly explaining why those cells do not die when they reactivate HIV. Here, we determine that the Casp8p41-Bcl2 complex is polyubiquitinated and degraded by the proteasome. Ixazomib, a proteasome inhibitor in clinical use, blocks this pathway, increasing the abundance of Casp8p41 and causing more cells to die in a Casp8p41-dependent manner.IMPORTANCE The Casp8p41 pathway of cell death is unique to HIV-infected cells yet is blocked by Bcl2. Once bound by Bcl2, Casp8p41 is polyubiquitinated and degraded by the proteasome. Proteasome inhibition blocks degradation of Casp8p41, increasing Casp8p41 levels and causing more HIV-infected cells to die.


Asunto(s)
Apoptosis , Caspasa 8/metabolismo , Infecciones por VIH/metabolismo , Proteasa del VIH/metabolismo , VIH-1/enzimología , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/patología , Linfocitos T CD4-Positivos/virología , Caspasa 8/genética , Infecciones por VIH/virología , Proteasa del VIH/genética , Humanos , Células Jurkat , Complejo de la Endopetidasa Proteasomal/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Replicación Viral
9.
Transfus Apher Sci ; 58(1): 100-106, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30616959

RESUMEN

BACKGROUND: In sickle cell disease (SCD), red blood cells (RBCs) containing hemoglobin S can be denser than RBCs containing wild-type hemoglobin, especially when dehydrated. We hypothesize that targeting denser RBCs during red blood cell (RBC) exchange for SCD could result in more efficient removal of dehydrated, sickled RBCs and preservation of non-sickled RBCs. STUDY DESIGN AND METHODS: Waste products from RBC exchanges for SCD were used as "simulated patients". One RBC volume was exchanged using ABO-compatible blood. The apheresis instrument was programmed to exchange the entire RBC layer by indicating the hematocrit (control), or the bottom half by indicating the hematocrit was half the hematocrit (experimental), with or without subsequent transfusion. Hemoglobin S levels, and complete blood counts were measured. RESULTS: Hemoglobin S levels were lower after the modified versus control RBC exchange (post-RBC exchange mean 4.96% and 11.27%); total hemoglobin S amounts were also lower (mean 19.27 and 58.29 mL of RBCs). Mean RBC density decreased after the modified RBC exchange by 8.86%. Hematocrit decreased in the modified RBC exchange by 36.37%, with partial correction by direct transfusion following a truncated RBC exchange. CONCLUSIONS: Targeting denser RBCs in RBC exchange enhanced hemoglobin S removal and decreased RBC density. Further development of this ex vivo model could potentially allow for: 1) improved reduction in hemoglobin S levels (allowing for longer periods between RBC exchange or maintained lower levels), or 2) achievement of previous goal hemoglobin S levels with fewer donor units (reducing alloimmunization risk and improving blood utilization).


Asunto(s)
Anemia de Células Falciformes/sangre , Transfusión de Eritrocitos/métodos , Humanos , Prueba de Estudio Conceptual
10.
Proc Natl Acad Sci U S A ; 113(31): 8783-8, 2016 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-27432972

RESUMEN

Despite years of plasma HIV-RNA levels <40 copies per milliliter during combination antiretroviral therapy (cART), the majority of HIV-infected patients exhibit persistent seropositivity to HIV-1 and evidence of immune activation. These patients also show persistence of proviruses of HIV-1 in circulating peripheral blood mononuclear cells. Many of these proviruses have been characterized as defective and thus thought to contribute little to HIV-1 pathogenesis. By combining 5'LTR-to-3'LTR single-genome amplification and direct amplicon sequencing, we have identified the presence of "defective" proviruses capable of transcribing novel unspliced HIV-RNA (usHIV-RNA) species in patients at all stages of HIV-1 infection. Although these novel usHIV-RNA transcripts had exon structures that were different from those of the known spliced HIV-RNA variants, they maintained translationally competent ORFs, involving elements of gag, pol, env, rev, and nef to encode a series of novel HIV-1 chimeric proteins. These novel usHIV-RNAs were detected in five of five patients, including four of four patients with prolonged viral suppression of HIV-RNA levels <40 copies per milliliter for more than 6 y. Our findings suggest that the persistent defective proviruses of HIV-1 are not "silent," but rather may contribute to HIV-1 pathogenesis by stimulating host-defense pathways that target foreign nucleic acids and proteins.


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Provirus/efectos de los fármacos , ARN Viral/metabolismo , ADN Viral/genética , ADN Viral/metabolismo , Regulación Viral de la Expresión Génica , Infecciones por VIH/virología , VIH-1/genética , VIH-1/fisiología , Humanos , Leucocitos Mononucleares/virología , Provirus/genética , ARN Viral/genética , Proteínas Virales/genética , Proteínas Virales/metabolismo
11.
Retrovirology ; 15(1): 22, 2018 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-29452580

RESUMEN

The identification of the most appropriate marker to measure reservoir size has been a great challenge for the HIV field. Quantitative viral outgrowth assay (QVOA), the reference standard to quantify the amount of replication-competent virus, has several limitations, as it is laborious, expensive, and unable to robustly reactivate every single integrated provirus. PCR-based assays have been developed as an easier, cheaper and less error-prone alternative to QVOA, but also have limitations. Historically, measuring integrated HIV DNA has provided insights about how reservoirs are formed and maintained. In the 1990s, measuring integrated HIV DNA was instrumental in understanding that a subset of resting CD4 T cells containing integrated HIV DNA were the major source of replication-competent virus. Follow-up studies have further characterized the phenotype of these cells containing integrated HIV DNA, as well as shown the correlation between the integration levels and clinical parameters, such as duration of infection, CD4 count and viral load. Integrated HIV DNA correlates with total HIV measures and with QVOA. The integration assay has several limitations. First, it largely overestimates the reservoir size, as both defective and replication-competent proviruses are detected. Since defective proviruses are the majority in patients on ART, it follows that the number of proviruses capable of reactivating and releasing new virions is significantly smaller than the number of integrated proviruses. Second, in patients on ART clonal expansion could theoretically lead to the preferential amplification of proviruses close to an Alu sequence though longitudinal studies have not captured this effect. Proviral sequencing combined with integration measures is probably the best estimate of reservoir size, but it is expensive, time-consuming and requires considerable bioinformatics expertise. All these reasons limit its use on a large scale. Herein, we review the utility of measuring HIV integration and suggest combining it with sequencing and total HIV measurements can provide insights that underlie reservoir maintenance.


Asunto(s)
Infecciones por VIH/virología , VIH-1/fisiología , Provirus/genética , Carga Viral , Integración Viral , Latencia del Virus , Enfermedad Aguda , Linfocitos T CD4-Positivos/virología , Enfermedad Crónica , Reservorios de Enfermedades , Humanos , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/normas , Replicación Viral
12.
Retrovirology ; 15(1): 18, 2018 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-29394935

RESUMEN

Recent years have seen a substantial increase in the number of tools available to monitor and study HIV reservoirs. Here, we discuss recent technological advances that enable an understanding of reservoir dynamics beyond classical assays to measure the frequency of cells containing provirus able to propagate a spreading infection (replication-competent reservoir). Specifically, we focus on the characterization of cellular reservoirs containing proviruses able to transcribe viral mRNAs (so called transcription-competent) and translate viral proteins (translation-competent). We suggest that the study of these alternative reservoirs provides complementary information to classical approaches, crucially at a single-cell level. This enables an in-depth characterization of the cellular reservoir, both following reactivation from latency and, importantly, directly ex vivo at baseline. Furthermore, we propose that the study of cellular reservoirs that may not contain fully replication-competent virus, but are able to produce HIV mRNAs and proteins, is of biological importance. Lastly, we detail some of the key contributions that the study of these transcription and translation-competent reservoirs has made thus far to investigations into HIV persistence, and outline where these approaches may take the field next.


Asunto(s)
Infecciones por VIH/virología , VIH-1/genética , Proteínas del Virus de la Inmunodeficiencia Humana/análisis , ARN Mensajero/análisis , ARN Viral/análisis , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Citometría de Flujo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Humanos , Hibridación in Situ , Provirus/genética , Análisis de la Célula Individual
13.
J Clin Microbiol ; 56(12)2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30232127

RESUMEN

We utilized pulsed-field gel electrophoresis (PFGE) to purify high-molecular-weight DNA from HIV-infected cells. This purification, in combination with our previously described droplet digital PCR (ddPCR) assay, was used to develop a method to quantify proviral integrated HIV DNA free of lower-molecular-weight species of HIV DNA. Episomal 2-long-terminal-repeat (2-LTR) circles were completely cleared from HIV DNA samples. Technical replicates of the complete assay, starting with the same specimens, resulted in no statistical differences in quantification of integrated HIV gag sequences in cellular DNA from cells from HIV-infected subjects after prolonged treatment with antiretroviral therapy (ART). The PFGE ddPCR assay was compared to the Alu-gag quantitative PCR (qPCR) assay, the most widely used assay to measure proviral integrated HIV DNA. Spearman's rho nonparametric correlation determined PFGE ddPCR results to be positively correlated with Alu-gag qPCR results (r = 0.7052; P = 0.0273). In summary, PFGE ddPCR is a sensitive, reproducible, and robust method to measure proviral integrated HIV DNA and is theoretically more accurate than previously described assays, because it is a direct measure of integrated HIV DNA.


Asunto(s)
Electroforesis en Gel de Campo Pulsado , Infecciones por VIH/virología , VIH-1/genética , Provirus/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Integración Viral/fisiología , ADN Viral/genética , ADN Viral/aislamiento & purificación , Productos del Gen gag/genética , Duplicado del Terminal Largo de VIH/genética , Humanos , Leucocitos Mononucleares/virología , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Reproducibilidad de los Resultados
14.
Transfusion ; 58(2): 330-338, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29230822

RESUMEN

BACKGROUND: Rapid analytics to predict circulating hematopoietic stem cells are valuable for optimal management of mobilization, particularly for the use of newer and costly mobilization agents such as plerixafor. STUDY DESIGN AND METHODS: We used stepwise, linear multiple regression modeling applied to cell population data collected by routine hematology analyzers (Beckman Coulter DxH 800) on patients undergoing autologous stem cell collection (n = 131). Beta coefficients were used to derive a formula for a stem cell index (SCI). We then tested the correlation of SCI with stem cell counts and performance of the SCI as a predictor of poor mobilization with external validation in a separate cohort (n = 183). RESULTS: The SCI correlated strongly with CD34 counts by flow cytometry (r = 0.8372 in the development cohort, r = 0.8332 in the external validation cohort) and compares favorably with other rapid stem cell enumerating technologies. In the external validation cohort, the SCI performed well as a predictor (receiver operating characteristic area under the curve, 0.9336) of poor mobilization (CD34 count < 10), with a sensitivity of 72% and a specificity of 93%. When prevalence of poor mobilization was 33%, this resulted in a positive predictive value of 83% and a negative predictive value of 87%. The SCI also showed promise in tracking responses to plerixafor administration. CONCLUSION: The findings demonstrate the utility of the cell population data collected by hematology analyzers to provide rapid data beyond standard complete blood counts, particularly for stem cell count prediction, requiring no additional reagents, specimen, or instrumentation.


Asunto(s)
Movilización de Célula Madre Hematopoyética , Compuestos Heterocíclicos/administración & dosificación , Células Madre de Sangre Periférica , Bencilaminas , Recuento de Células Sanguíneas/instrumentación , Recuento de Células Sanguíneas/métodos , Ciclamas , Femenino , Humanos , Masculino
15.
J Virol ; 90(2): 1148-51, 2016 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-26559833

RESUMEN

Cell-associated HIV unspliced RNA is an important marker of the viral reservoir. HIV gag RNA-specific assays are frequently used to monitor reservoir activation. Because HIV preferentially integrates into actively transcribed genes, some of the transcripts detected by these assays may not represent genuine HIV RNA but rather chimeric host-HIV readthrough transcripts. Here, we demonstrate that in HIV-infected patients on suppressive combination antiretroviral therapy, such host-derived transcripts do not significantly contribute to the HIV gag RNA level.


Asunto(s)
VIH/fisiología , Provirus/genética , ARN Viral/biosíntesis , Transcripción Genética , Activación Viral , Perfilación de la Expresión Génica , VIH/genética , Humanos
16.
J Virol ; 90(23): 10436-10445, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27630237

RESUMEN

The dynamics of HIV reservoir accumulation off antiretroviral therapy (ART) is underexplored. Levels of integrated HIV DNA in peripheral blood mononuclear cells (PBMCs) were longitudinally monitored before and after antiviral therapy. HIV integration increased over time in both elite controllers (ECs; n = 8) and noncontrollers (NCs; n = 6) before ART, whereas integration remained stable in patients on ART (n = 4). The median annual fold change was higher in NCs than in ECs and negatively correlated with CD4/CD8 T-cell ratio. Cytotoxic T lymphocyte (CTL) function as assessed by infected CD4 T-cell elimination (ICE) and granzyme B activity did not significantly change over time in ECs, suggesting that the gradual increase in integrated HIV DNA observed in ECs was not a result of progressive loss of immune-mediated control. Also, acutely infected (n = 7) but not chronically infected (n = 6) patients exhibited a significant drop in integrated HIV DNA 12 months after ART initiation. In conclusion, in the absence of ART, integrated HIV accumulates over time both in NCs and in ECs, at variable individual rates. Starting ART early in infection leads to a greater drop in integrated HIV DNA than does initiating treatment after years of infection. The increase in integrated HIV DNA over time suggests that early treatment may be of benefit in limiting HIV reservoirs. IMPORTANCE: The establishment of a latent reservoir represents a barrier to cure among HIV-infected individuals. The dynamics of HIV reservoir accumulation over time in patients before antiviral therapy is underexplored, in large part because it is difficult to accurately and reproducibly measure the size of HIV reservoir in this setting. In our study, we compared the dynamics of integrated HIV DNA over time in ECs and NCs before and after ART was initiated. We found that integrated HIV DNA levels progressively increase over time in the absence of ART, but with a higher, albeit variable, rate in NCs compared to ECs. In addition, integrated HIV DNA declines more dramatically when ART is initiated in acute rather than chronic HIV infection, suggesting important differences between acute and chronic infection. Our study highlights the role of HIV replication and CTL control in reservoir accumulation in sanctuary sites and why ART appears to be more effective in acute infection.


Asunto(s)
Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH/inmunología , VIH/fisiología , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/virología , Integración Viral/inmunología , Enfermedad Aguda , Fármacos Anti-VIH/uso terapéutico , Enfermedad Crónica , ADN Viral/sangre , ADN Viral/genética , Reservorios de Enfermedades/virología , VIH/genética , Infecciones por VIH/tratamiento farmacológico , Humanos , Estudios Longitudinales , Carga Viral/inmunología , Replicación Viral/inmunología
17.
J Virol ; 90(5): 2165-79, 2015 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-26537682

RESUMEN

UNLABELLED: A major goal in HIV eradication research is characterizing the reservoir cells that harbor HIV in the presence of antiretroviral therapy (ART), which reseed viremia after treatment is stopped. In general, it is assumed that the reservoir consists of CD4(+) T cells that express no viral proteins. However, recent findings suggest that this may be an overly simplistic view and that the cells that contribute to the reservoir may be a diverse population that includes both CD4(+) and CD4(-) cells. In this study, we directly infected resting CD4(+) T cells and used fluorescence-activated cell sorting (FACS) and fiber-optic array scanning technology (FAST) to identify and image cells expressing HIV Gag. We found that Gag expression from integrated proviruses occurred in resting cells that lacked surface CD4, likely resulting from Nef- and Env-mediated receptor internalization. We also extended our approach to detect cells expressing HIV proteins in patients suppressed on ART. We found evidence that rare Gag(+) cells persist during ART and that these cells are often negative for CD4. We propose that these double-negative α/ß T cells that express HIV protein may be a component of the long-lived reservoir. IMPORTANCE: A reservoir of infected cells persists in HIV-infected patients during antiretroviral therapy (ART) that leads to rebound of virus if treatment is stopped. In this study, we used flow cytometry and cell imaging to characterize protein expression in HIV-infected resting cells. HIV Gag protein can be directly detected in infected resting cells and occurs with simultaneous loss of CD4, consistent with the expression of additional viral proteins, such as Env and Nef. Gag(+) CD4(-) cells can also be detected in suppressed patients, suggesting that a subset of infected cells express proteins during ART. Understanding the regulation of viral protein expression during ART will be key to designing effective strategies to eradicate HIV reservoirs.


Asunto(s)
Antirretrovirales/uso terapéutico , Antígenos CD4/análisis , Antígenos CD8/análisis , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Subgrupos de Linfocitos T/virología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/biosíntesis , Citometría de Flujo , Humanos , Imagen Óptica , Subgrupos de Linfocitos T/química
18.
PLoS Pathog ; 9(2): e1003174, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23459007

RESUMEN

HIV-1 reservoirs preclude virus eradication in patients receiving highly active antiretroviral therapy (HAART). The best characterized reservoir is a small, difficult-to-quantify pool of resting memory CD4(+) T cells carrying latent but replication-competent viral genomes. Because strategies targeting this latent reservoir are now being tested in clinical trials, well-validated high-throughput assays that quantify this reservoir are urgently needed. Here we compare eleven different approaches for quantitating persistent HIV-1 in 30 patients on HAART, using the original viral outgrowth assay for resting CD4(+) T cells carrying inducible, replication-competent viral genomes as a standard for comparison. PCR-based assays for cells containing HIV-1 DNA gave infected cell frequencies at least 2 logs higher than the viral outgrowth assay, even in subjects who started HAART during acute/early infection. This difference may reflect defective viral genomes. The ratio of infected cell frequencies determined by viral outgrowth and PCR-based assays varied dramatically between patients. Although strong correlations with the viral outgrowth assay could not be formally excluded for most assays, correlations achieved statistical significance only for integrated HIV-1 DNA in peripheral blood mononuclear cells and HIV-1 RNA/DNA ratio in rectal CD4(+) T cells. Residual viremia was below the limit of detection in many subjects and did not correlate with the viral outgrowth assays. The dramatic differences in infected cell frequencies and the lack of a precise correlation between culture and PCR-based assays raise the possibility that the successful clearance of latently infected cells may be masked by a larger and variable pool of cells with defective proviruses. These defective proviruses are detected by PCR but may not be affected by reactivation strategies and may not require eradication to accomplish an effective cure. A molecular understanding of the discrepancy between infected cell frequencies measured by viral outgrowth versus PCR assays is an urgent priority in HIV-1 cure research.


Asunto(s)
ADN Viral/análisis , Reservorios de Enfermedades/virología , Infecciones por VIH/virología , VIH/aislamiento & purificación , Provirus/aislamiento & purificación , ARN Viral/análisis , Carga Viral/efectos de los fármacos , Adulto , Anciano , Terapia Antirretroviral Altamente Activa , Linfocitos T CD4-Positivos/efectos de los fármacos , ADN Viral/efectos de los fármacos , ADN Viral/genética , Femenino , VIH/genética , VIH/crecimiento & desarrollo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/virología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Provirus/genética , Provirus/crecimiento & desarrollo , ARN Viral/efectos de los fármacos , ARN Viral/genética , Integración Viral/efectos de los fármacos
19.
PLoS Pathog ; 9(10): e1003691, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24130489

RESUMEN

The study of HIV-infected "controllers" who are able to maintain low levels of plasma HIV RNA in the absence of antiretroviral therapy (ART) may provide insights for HIV cure and vaccine strategies. Despite maintaining very low levels of plasma viremia, controllers have elevated immune activation and accelerated atherosclerosis. However, the degree to which low-level replication contributes to these phenomena is not known. Sixteen asymptomatic controllers were prospectively treated with ART for 24 weeks. Controllers had a statistically significant decrease in ultrasensitive plasma and rectal HIV RNA levels with ART. Markers of T cell activation/dysfunction in blood and gut mucosa also decreased substantially with ART. Similar reductions were observed in the subset of "elite" controllers with pre-ART plasma HIV RNA levels below conventional assays (<40 copies/mL). These data confirm that HIV replication persists in controllers and contributes to a chronic inflammatory state. ART should be considered for these individuals (ClinicalTrials.gov NCT01025427).


Asunto(s)
Antirretrovirales/administración & dosificación , Aterosclerosis , Infecciones por VIH , VIH-1/fisiología , ARN Viral/sangre , Replicación Viral/efectos de los fármacos , Adulto , Aterosclerosis/sangre , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/etiología , Biomarcadores/sangre , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Humanos , Activación de Linfocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Linfocitos T/metabolismo , Factores de Tiempo
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