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1.
J Infect Dis ; 229(6): 1786-1790, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38226493

RESUMEN

A subset of antiretroviral therapy-treated persons with human immunodeficiency virus (HIV), referred to as immunological nonresponders (INRs), fails to normalize CD4+ T-cell numbers. In a case-control study involving 26 INRs (CD4 < 250 cells/µL) and 25 immunological responders (IRs; CD4 ≥ 250 cells/µL), we evaluated the potential contribution of transcriptionally competent defective HIV-1 proviruses to poor CD4+ T-cell recovery. Compared to the responders, the INRs had higher levels of cell-associated HIV RNA (P = .034) and higher percentages of HLA-DR+ CD4+ T cells (P < .001). While not encoding replication-competent viruses, the RNA transcripts frequently encoded HIV-1 Gag-p17 and Nef proteins. These transcripts and/or resulting proteins may activate pathway(s) leading to the immunological nonresponse phenotype.


Asunto(s)
Linfocitos T CD4-Positivos , Infecciones por VIH , VIH-1 , Provirus , Humanos , VIH-1/genética , VIH-1/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Infecciones por VIH/genética , Masculino , Estudios de Casos y Controles , Femenino , Adulto , Provirus/genética , Persona de Mediana Edad , Linfocitos T CD4-Positivos/inmunología , ARN Viral/genética , Recuento de Linfocito CD4 , Transcripción Genética , Antirretrovirales/uso terapéutico , Terapia Antirretroviral Altamente Activa
2.
Proc Natl Acad Sci U S A ; 117(7): 3704-3710, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-32029589

RESUMEN

HIV-1 proviruses persist in the CD4+ T cells of HIV-infected individuals despite years of combination antiretroviral therapy (cART) with suppression of HIV-1 RNA levels <40 copies/mL. Greater than 95% of these proviruses detected in circulating peripheral blood mononuclear cells (PBMCs) are referred to as "defective" by virtue of having large internal deletions and lethal genetic mutations. As these defective proviruses are unable to encode intact and replication-competent viruses, they have long been thought of as biologically irrelevant "graveyard" of viruses with little significance to HIV-1 pathogenesis. Contrary to this notion, we have recently demonstrated that these defective proviruses are not silent, are capable of transcribing novel unspliced forms of HIV-RNA transcripts with competent open reading frames (ORFs), and can be found in the peripheral blood CD4+ T cells of patients at all stages of HIV-1 infection. In the present study, by an approach of combining serial dilutions of CD4+ T cells and T cell-cloning technologies, we are able to demonstrate that defective proviruses that persist in HIV-infected individuals during suppressive cART are translationally competent and produce the HIV-1 Gag and Nef proteins. The HIV-RNA transcripts expressed from these defective proviruses may trigger an element of innate immunity. Likewise, the viral proteins coded in the defective proviruses may form extracellular virus-like particles and may trigger immune responses. The persistent production of HIV-1 proteins in the absence of viral replication helps explain persistent immune activation despite HIV-1 levels below detection, and also presents new challenges to HIV-1 eradication.


Asunto(s)
Infecciones por VIH/virología , VIH-1/metabolismo , Provirus/metabolismo , Proteínas Virales/metabolismo , Linfocitos T CD4-Positivos/virología , VIH-1/genética , Humanos , Leucocitos Mononucleares/virología , Masculino , Persona de Mediana Edad , Provirus/genética , Proteínas Virales/genética
3.
Antimicrob Agents Chemother ; 66(1): e0150021, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34723625

RESUMEN

Resistance to anti-HIV drugs has been a problem from the beginning of antiviral drug treatments. The recent expansion of combination antiretroviral therapy worldwide has led to an increase in resistance to antiretrovirals; understanding the mechanisms of resistance is increasingly important. In this study, we analyzed reverse transcriptase (RT) variants based on sequences derived from an individual who had low-level rebound viremia while undergoing therapy with abacavir, azidothymidine (AZT) (zidovudine), and (-)-l-2',3'-dideoxy-3'-thiacytidine (3TC) (lamivudine). The RT had mutations at positions 64, 67, 70, 184, and 219 and a threonine insertion after amino acid 69 in RT. The virus remained partially susceptible to the nucleoside RT inhibitor (NRTI) regimen. We show how these mutations affect the ability of NRTIs to inhibit DNA synthesis by RT. The presence of the inserted threonine reduced the susceptibility of the RT mutant to inhibition by tenofovir.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , VIH-1 , Aminoácidos , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Infecciones por VIH/tratamiento farmacológico , Transcriptasa Inversa del VIH/metabolismo , VIH-1/genética , VIH-1/metabolismo , Humanos , Lamivudine/farmacología , Mutación/genética , Inhibidores de la Transcriptasa Inversa/química , Zidovudina/farmacología
4.
J Antimicrob Chemother ; 76(7): 1898-1906, 2021 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-33792714

RESUMEN

OBJECTIVES: With the goal of facilitating the use of HIV-TRePS to optimize therapy in settings with limited healthcare resources, we aimed to develop computational models to predict treatment responses accurately in the absence of commonly used baseline data. METHODS: Twelve sets of random forest models were trained using very large, global datasets to predict either the probability of virological response (classifier models) or the absolute change in viral load in response to a new regimen (absolute models) following virological failure. Two 'standard' models were developed with all baseline variables present and 10 others developed without HIV genotype, time on therapy, CD4 count or any combination of the above. RESULTS: The standard classifier models achieved an AUC of 0.89 in cross-validation and independent testing. Models with missing variables achieved AUC values of 0.78-0.90. The standard absolute models made predictions that correlated significantly with observed changes in viral load with a mean absolute error of 0.65 log10 copies HIV RNA/mL in cross-validation and 0.69 log10 copies HIV RNA/mL in independent testing. Models with missing variables achieved values of 0.65-0.75 log10 copies HIV RNA/mL. All models identified alternative regimens that were predicted to be effective for the vast majority of cases where the new regimen prescribed in the clinic failed. All models were significantly better predictors of treatment response than genotyping with rules-based interpretation. CONCLUSIONS: These latest models that predict treatment responses accurately, even when a number of baseline variables are not available, are a major advance with greatly enhanced potential benefit, particularly in resource-limited settings. The only obstacle to realizing this potential is the willingness of healthcare professions to use the system.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Atención a la Salud , Genotipo , VIH/genética , Infecciones por VIH/tratamiento farmacológico , Humanos , ARN Viral , Carga Viral
5.
J Virol ; 94(23)2020 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-32907983

RESUMEN

In various infections or vaccinations of mice or humans, reports of the persistence and the requirements for restimulation of the cytotoxic mediators granzyme B (GrB) and perforin (PRF) in CD8+ T cells have yielded disparate results. In this study, we examined the kinetics of PRF and GrB mRNA and protein expression after stimulation and associated changes in cytotoxic capacity in virus-specific memory cells in detail. In patients with controlled HIV or cleared respiratory syncytial virus (RSV) or influenza virus infections, all virus-specific CD8+ T cells expressed low PRF levels without restimulation. Following stimulation, they displayed similarly delayed kinetics for lytic protein expression, with significant increases occurring by days 1 to 3 before peaking on days 4 to 6. These increases were strongly correlated with, but were not dependent upon, proliferation. Incremental changes in PRF and GrB percent expression and mean fluorescence intensity (MFI) were highly correlated with increases in HIV-specific cytotoxicity. mRNA levels in HIV-specific CD8+ T-cells exhibited delayed kinetics after stimulation as with protein expression, peaking on day 5. In contrast to GrB, PRF mRNA transcripts were little changed over 5 days of stimulation (94-fold versus 2.8-fold, respectively), consistent with posttranscriptional regulation. Changes in expression of some microRNAs, including miR-17, miR-150, and miR-155, suggested that microRNAs might play a significant role in regulation of PRF expression. Therefore, under conditions of extremely low or absent antigen levels, memory virus-specific CD8+ T cells require prolonged stimulation over days to achieve maximal lytic protein expression and cytotoxic capacity.IMPORTANCE Antigen-specific CD8+ T cells play a major role in controlling most virus infections, primarily by perforin (PRF)- and granzyme B (GrB)-mediated apoptosis. There is considerable controversy regarding whether PRF is constitutively expressed, rapidly increased similarly to a cytokine, or delayed in its expression with more prolonged stimulation in virus-specific memory CD8+ T cells. In this study, the degree of cytotoxic capacity of virus-specific memory CD8+ T cells was directly proportional to the content of lytic molecules, which required antigenic stimulation over several days for maximal levels. This appeared to be modulated by increases in GrB transcription and microRNA-mediated posttranscriptional regulation of PRF expression. Clarifying the requirements for maximal cytotoxic capacity is critical to understanding how viral clearance might be mediated by memory cells and what functions should be induced by vaccines and immunotherapies.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Infecciones por VIH/inmunología , Animales , Antígenos CD8/metabolismo , Granzimas/metabolismo , VIH/metabolismo , Infecciones por VIH/metabolismo , Humanos , Cinética , Ratones , MicroARNs , Perforina , ARN Mensajero/metabolismo
6.
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
7.
Proc Natl Acad Sci U S A ; 113(7): 1883-8, 2016 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-26858442

RESUMEN

Reservoirs of infectious HIV-1 persist despite years of combination antiretroviral therapy and make curing HIV-1 infections a major challenge. Most of the proviral DNA resides in CD4(+)T cells. Some of these CD4(+)T cells are clonally expanded; most of the proviruses are defective. It is not known if any of the clonally expanded cells carry replication-competent proviruses. We report that a highly expanded CD4(+) T-cell clone contains an intact provirus. The highly expanded clone produced infectious virus that was detected as persistent plasma viremia during cART in an HIV-1-infected patient who had squamous cell cancer. Cells containing the intact provirus were widely distributed and significantly enriched in cancer metastases. These results show that clonally expanded CD4(+)T cells can be a reservoir of infectious HIV-1.


Asunto(s)
Linfocitos T CD4-Positivos/virología , VIH-1/fisiología , Replicación Viral , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/sangre , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/patogenicidad , Humanos , Datos de Secuencia Molecular , Virulencia
8.
J Antimicrob Chemother ; 73(8): 2186-2196, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29889249

RESUMEN

Objectives: Optimizing antiretroviral drug combination on an individual basis can be challenging, particularly in settings with limited access to drugs and genotypic resistance testing. Here we describe our latest computational models to predict treatment responses, with or without a genotype, and compare their predictive accuracy with that of genotyping. Methods: Random forest models were trained to predict the probability of virological response to a new therapy introduced following virological failure using up to 50 000 treatment change episodes (TCEs) without a genotype and 18 000 TCEs including genotypes. Independent data sets were used to evaluate the models. This study tested the effects on model accuracy of relaxing the baseline data timing windows, the use of a new filter to exclude probable non-adherent cases and the addition of maraviroc, tipranavir and elvitegravir to the system. Results: The no-genotype models achieved area under the receiver operator characteristic curve (AUC) values of 0.82 and 0.81 using the standard and relaxed baseline data windows, respectively. The genotype models achieved AUC values of 0.86 with the new non-adherence filter and 0.84 without. Both sets of models were significantly more accurate than genotyping with rules-based interpretation, which achieved AUC values of only 0.55-0.63, and were marginally more accurate than previous models. The models were able to identify alternative regimens that were predicted to be effective for the vast majority of cases in which the new regimen prescribed in the clinic failed. Conclusions: These latest global models predict treatment responses accurately even without a genotype and have the potential to help optimize therapy, particularly in resource-limited settings.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Simulación por Computador , Infecciones por VIH/tratamiento farmacológico , Respuesta Virológica Sostenida , Adulto , Países en Desarrollo , Sustitución de Medicamentos , Femenino , Humanos , Masculino , Maraviroc/uso terapéutico , Piridinas/uso terapéutico , Pironas/uso terapéutico , Quinolonas/uso terapéutico , Sulfonamidas , Resultado del Tratamiento
9.
Immunity ; 29(6): 1009-21, 2008 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-19062316

RESUMEN

Virus-specific CD8+ T cells probably mediate control over HIV replication in rare individuals, termed long-term nonprogressors (LTNPs) or elite controllers. Despite extensive investigation, the mechanisms responsible for this control remain incompletely understood. We observed that HIV-specific CD8+ T cells of LTNPs persisted at higher frequencies than those of treated progressors with equally low amounts of HIV. Measured on a per-cell basis, HIV-specific CD8+ T cells of LTNPs efficiently eliminated primary autologous HIV-infected CD4+ T cells. This function required lytic granule loading of effectors and delivery of granzyme B to target cells. Defective cytotoxicity of progressor effectors could be restored after treatment with phorbol ester and calcium ionophore. These results establish an effector function and mechanism that clearly segregate with immunologic control of HIV. They also demonstrate that lytic granule contents of memory cells are a critical determinant of cytotoxicity that must be induced for maximal per-cell killing capacity.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Citotoxicidad Inmunológica , Infecciones por VIH/inmunología , VIH-1/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/enzimología , Linfocitos T CD8-positivos/virología , Degranulación de la Célula/inmunología , Gránulos Citoplasmáticos/enzimología , Gránulos Citoplasmáticos/inmunología , Granzimas/inmunología , Granzimas/metabolismo , Infecciones por VIH/virología , Sobrevivientes de VIH a Largo Plazo , Humanos , Interferón gamma/inmunología , Interferón gamma/metabolismo , Perforina/inmunología , Perforina/metabolismo , ARN Viral/inmunología
10.
Clin Infect Dis ; 63(6): 836-843, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27307507

RESUMEN

BACKGROUND: Washington, DC, has 2.5% human immunodeficiency virus (HIV) prevalence, 3.9% among African Americans. Antiretrovirals (ARTs) are the cornerstone for treatment and prevention. Monitoring changes in transmitted drug resistance (TDR) is critical for effective HIV care. METHODS: HIV genotype data for individuals enrolled in research studies in metropolitan Washington, D.C., were used to identify TDR using the World Health Organization mutation list [Bennett DE, Camacho RJ, Otelea D, et al. Drug resistance mutations for surveillance of transmitted HIV-1 drug-resistance: 2009 update. PloS One 2009; 4:e4724]. HIV phylogenies were reconstructed using maximum likelihood and Bayesian methods. HIV transmission clusters were supported by 1000 bootstrap values >0.70 and posterior probability >0.95 of having a common ancestor. RESULTS: Among 710 individuals enrolled in 1994-2013, the median age was 38.6 years, 46.2% were female, and 53.3% were African-American. TDR was 22.5% among 566 treatment-naive individuals; 15.8% had nucleoside/nucleotide reverse transcriptase inhibitor (NRTI) resistance, 9.8% had nonnucleoside reverse-transcriptase inhibitor (NNRTI) resistance, and 4.2% had protease inhibitor (PI) resistance. Single class TDR was 10.0%, 5.1%, and 1.6% to NRTIs, NNRTIs, and PIs. Dual TDR to PI and NRTI was seen in 1.6%, NRTI and NNRTI in 3.4%, and triple class TDR in 0.9%. TDR frequency decreased from 1994-2006 (27.1%) to 2007-2013 (19.4%; P = .02). Only 6/79 (7.6%) individuals within transmission clusters had evidence of TDR. DISCUSSIONS: We identified high prevalence of TDR among HIV-infected individuals in metropolitan Washington, DC, regardless of gender. Active surveillance for TDR is needed to guide ART usage and analyses of risk group contributions to HIV transmission and resistance.


Asunto(s)
Fármacos Anti-VIH/farmacología , Farmacorresistencia Viral/genética , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , VIH-1 , Adulto , Fármacos Anti-VIH/uso terapéutico , Teorema de Bayes , District of Columbia/epidemiología , Femenino , Infecciones por VIH/tratamiento farmacológico , VIH-1/clasificación , VIH-1/efectos de los fármacos , VIH-1/genética , Humanos , Masculino , Filogenia , Estudios Retrospectivos
11.
PLoS Pathog ; 10(3): e1004010, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24651464

RESUMEN

A better understanding of changes in HIV-1 population genetics with combination antiretroviral therapy (cART) is critical for designing eradication strategies. We therefore analyzed HIV-1 genetic variation and divergence in patients' plasma before cART, during suppression on cART, and after viral rebound. Single-genome sequences of plasma HIV-1 RNA were obtained from HIV-1 infected patients prior to cART (N = 14), during suppression on cART (N = 14) and/or after viral rebound following interruption of cART (N = 5). Intra-patient population diversity was measured by average pairwise difference (APD). Population structure was assessed by phylogenetic analyses and a test for panmixia. Measurements of intra-population diversity revealed no significant loss of overall genetic variation in patients treated for up to 15 years with cART. A test for panmixia, however, showed significant changes in population structure in 2/10 patients after short-term cART (<1 year) and in 7/10 patients after long-term cART (1-15 years). The changes consisted of diverse sets of viral variants prior to cART shifting to populations containing one or more genetically uniform subpopulations during cART. Despite these significant changes in population structure, rebound virus after long-term cART had little divergence from pretherapy virus, implicating long-lived cells infected before cART as the source for rebound virus. The appearance of genetically uniform virus populations and the lack of divergence after prolonged cART and cART interruption provide strong evidence that HIV-1 persists in long-lived cells infected before cART was initiated, that some of these infected cells may be capable of proliferation, and that on-going cycles of viral replication are not evident.


Asunto(s)
Antirretrovirales/uso terapéutico , Evolución Molecular , Infecciones por VIH/virología , VIH-1/genética , ARN Viral/efectos de los fármacos , Adulto , Fármacos Anti-VIH/uso terapéutico , Femenino , Variación Genética/efectos de los fármacos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , Humanos , Masculino , Persona de Mediana Edad , Filogenia , ARN Viral/análisis , ARN Viral/genética , Replicación Viral/efectos de los fármacos , Replicación Viral/genética
12.
J Virol ; 87(18): 10313-23, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23678164

RESUMEN

HIV infection is characterized by rapid and error-prone viral replication resulting in genetically diverse virus populations. The rate of accumulation of diversity and the mechanisms involved are under intense study to provide useful information to understand immune evasion and the development of drug resistance. To characterize the development of viral diversity after infection, we carried out an in-depth analysis of single genome sequences of HIV pro-pol to assess diversity and divergence and to estimate replicating population sizes in a group of treatment-naive HIV-infected individuals sampled at single (n = 22) or multiple, longitudinal (n = 11) time points. Analysis of single genome sequences revealed nonlinear accumulation of sequence diversity during the course of infection. Diversity accumulated in recently infected individuals at rates 30-fold higher than in patients with chronic infection. Accumulation of synonymous changes accounted for most of the diversity during chronic infection. Accumulation of diversity resulted in population shifts, but the rates of change were low relative to estimated replication cycle times, consistent with relatively large population sizes. Analysis of changes in allele frequencies revealed effective population sizes that are substantially higher than previous estimates of approximately 1,000 infectious particles/infected individual. Taken together, these observations indicate that HIV populations are large, diverse, and slow to change in chronic infection and that the emergence of new mutations, including drug resistance mutations, is governed by both selection forces and drift.


Asunto(s)
Variación Genética , Infecciones por VIH/virología , VIH/clasificación , VIH/genética , Adulto , Sustitución de Aminoácidos , Femenino , VIH/aislamiento & purificación , Proteasa del VIH/genética , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Mutación Missense , Análisis de Secuencia de ADN , Adulto Joven , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética
13.
Blood ; 119(20): 4645-55, 2012 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-22490332

RESUMEN

True long-term nonprogressors (LTNPs)/elite controllers (ECs) maintain durable control over HIV replication without antiretroviral therapy. Herein we describe 4 unique persons who were distinct from conventional LTNPs/ECs in that they had extraordinarily low HIV burdens and comparatively weak immune responses. As a group, typical LTNPs/ECs have unequivocally reactive HIV-1 Western blots, viral loads below the lower threshold of clinical assays, low levels of persistent viral reservoirs, an over-representation of protective HLA alleles, and robust HIV-specific CD8(+) T-cell responses. The 4 unique cases were distinguished from typical LTNPs/ECs based on weakly reactive Western blots, undetectable plasma viremia by a single copy assay, extremely low to undetectable HIV DNA levels, and difficult to isolate replication-competent virus. All 4 had at least one protective HLA allele and CD8(+) T-cell responses that were disproportionately high for the low antigen levels but comparatively lower than those of typical LTNPs/ECs. These unique persons exhibit extraordinary suppression over HIV replication, therefore, higher-level control than has been demonstrated in previous studies of LTNPs/ECs. Additional insight into the full spectrum of immune-mediated suppression over HIV replication may enhance our understanding of the associated mechanisms, which should inform the design of efficacious HIV vaccines and immunotherapies.


Asunto(s)
Infecciones por VIH/inmunología , Sobrevivientes de VIH a Largo Plazo , VIH-1/inmunología , Adulto , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/virología , Seropositividad para VIH/inmunología , Seropositividad para VIH/virología , VIH-1/fisiología , Humanos , Masculino , Persona de Mediana Edad , Carga Viral , Replicación Viral/inmunología , Replicación Viral/fisiología
14.
Eur J Immunol ; 42(10): 2608-20, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22777759

RESUMEN

HIV-induced immune activation leads to expansion of a subset of human CD8(+) T cells expressing HLA-DR antigens. Expansion of CD8(+) HLA-DR(+) T cells can be also observed in non-HIV settings including several autoimmune diseases and aging. Although these cells are felt to represent "immune exhaustion" and/or to be anergic, their precise role in host defense has remained unclear. Here, we report that this subset of cells exhibits a restricted repertoire, shows evidence of multiple rounds of division, but lacks markers of recent TCR engagement. Detailed cell cycle analysis revealed that compared with their CD8(+) HLA-DR(-) counterpart, the CD8(+) HLA-DR(+) T-cell pool contained an increased fraction of cells in S-phase with elevated levels of the G2/M regulators: cyclin A2, CDC25C, Cdc2 (CDK1), indicating that these cells are not truly anergic but rather experiencing proliferation in vivo. Together, these data support a hypothesis that antigen stimulation leads to the initial expansion of a CD8(+) pool of cells in vivo that undergo further expansion independent of ongoing TCR engagement. No qualitative differences were noted between CD8(+) HLA-DR(+) cells from HIV(+) and HIV(-) donors, indicating that the generation of CD8(+) HLA-DR(+) T cells is a part of normal immune regulation that is exaggerated in the setting of HIV-1 infection.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Antígenos HLA-DR/metabolismo , Subgrupos de Linfocitos T/inmunología , Adulto , Biomarcadores/metabolismo , Linfocitos T CD8-positivos/virología , Ciclo Celular , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferación Celular , Células Cultivadas , Anergia Clonal , Regulación de la Expresión Génica/inmunología , Humanos , Activación de Linfocitos , Persona de Mediana Edad , Receptores de Antígenos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/virología
15.
Am J Nephrol ; 37(5): 443-51, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23615312

RESUMEN

BACKGROUND/AIMS: Microalbuminuria is a marker for early kidney disease and cardiovascular risk. The purposes of this study were to determine the prevalence of microalbuminuria in an HIV-infected clinic population, to test the predictive value of a single urine albumin/creatinine ratio (ACR) to identify persistent microalbuminuria and to examine covariates of microalbuminuria. METHODS: We conducted a prospective cohort study of HIV-infected subjects (n = 182) without proteinuria (urine protein/creatinine ratio ≥0.5 g/g), elevated serum creatinine, diabetes, or chronic inflammatory conditions. Subjects completed three research visits within 9 months. Microalbuminuria was defined as the geometric mean ACR of 25-355 mg/g for females and 17-250 mg/g for males. RESULTS: The prevalence of microalbuminuria was 14%. The negative predictive value of a single urine ACR determination was 98%, whereas the positive predictive value was only 74%. Microalbuminuria was similar among Black (15%) and non-Black (14%) subjects (p = 0.8). Subjects with microalbuminuria were more likely to have hypertension (p = 0.02) and metabolic syndrome (p = 0.03). While duration of HIV infection and the level of HIV viremia were similar between groups, those with microalbuminuria were more likely to have a CD4 count <200 cells/µl (p = 0.0003). In a multivariate logistic regression analysis, the only significant independent predictors of microalbuminuria were low CD4 count (p = 0.018) and current ritonavir exposure (p = 0.04). CONCLUSION: The prevalence of microalbuminuria in an HIV-infected clinic population was similar to earlier reports, and was associated with hypertension and impaired immune function. A single normal ACR determination effectively excludes microalbuminuria, whereas an elevated ACR requires confirmation.


Asunto(s)
Albuminuria/epidemiología , Infecciones por VIH/epidemiología , Adulto , Albuminuria/etiología , Albuminuria/orina , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/metabolismo , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Prevalencia , Estudios Prospectivos , Estados Unidos/epidemiología
16.
J Immunol ; 186(4): 2106-16, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21257970

RESUMEN

Immune activation plays an important role in the pathogenesis of HIV disease. Although the causes are not fully understood, the forces that lead to immune dysfunction differ for CD4 and CD8 T cells. In this study, we report that the molecular pathways that drive immune activation during chronic HIV infection are influenced by differences in the homeostatic regulation of the CD4 and CD8 T cell pools. Proliferation of CD4 T cells is controlled more tightly by CD4 T cell numbers than is CD8 T cell proliferation. This difference reflects the importance of maintaining a polyclonal CD4 T cell pool in host surveillance. Both pools of T cells were found to be driven by viral load and its associated state of inflammation. In the setting of HIV-induced lymphopenia, naive CD4 T cells were recruited mainly into the proliferating pool in response to CD4 T cell depletion, whereas naive CD8 T cell proliferation was driven mainly by levels of HIV RNA. RNA analysis revealed increased expression of genes associated with type I IFN and common γ chain cytokine signaling in CD4 T cell subsets and only type I IFN-associated genes in CD8 T cell subsets. In vitro studies demonstrated enhanced STAT1 phosphorylation in response to IFN-α and increased expression of the IFNAR1 transcripts in naive and memory CD4 T cells compared with that observed in CD8 T cells. CD4 T cell subsets also showed enhanced STAT1 phosphorylation in response to exogenous IL-7.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/inmunología , Homeostasis/inmunología , Interferón Tipo I/fisiología , Interleucina-7/fisiología , Activación de Linfocitos/inmunología , ARN Viral/fisiología , Adulto , Relación CD4-CD8 , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/virología , Proliferación Celular , Enfermedad Crónica , Estudios de Cohortes , Femenino , Infecciones por VIH/metabolismo , Infecciones por VIH/patología , Humanos , Interferón-alfa/fisiología , Interleucina-7/farmacología , Linfopenia/inmunología , Linfopenia/metabolismo , Linfopenia/patología , Masculino , Persona de Mediana Edad , Fosforilación/inmunología , ARN Viral/biosíntesis , ARN Viral/sangre , Fase de Descanso del Ciclo Celular/inmunología , Factor de Transcripción STAT1/metabolismo , Carga Viral/inmunología
17.
J Infect Dis ; 205(9): 1382-90, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-22454463

RESUMEN

BACKGROUND: Elevated serum interleukin 7 (IL-7) levels are observed in lymphopenic conditions, including idiopathic CD4 lymphopenia (ICL), which is characterized by CD4 lymphopenia in the absence of human immunodeficiency virus infection or other known immunodeficiency. METHODS: To test whether defective IL-7 signaling could be an etiologic or contributing factor in ICL, peripheral blood mononuclear cells from patients with ICL (median CD4 T-cell count, 160 cells/µL) and healthy controls (median CD4 T-cell count, 582 cells/µL) were evaluated for expression of IL-7Rα chain (CD127) and intracellular phosphorylated STAT-5 (a marker of γc cytokine signaling) after cytokine stimulation. Gene expression was analyzed by real-time polymerase chain reaction following IL-7 stimulation. RESULTS: The percentage of CD4+CD127+ T cells was lower in patients with ICL, compared with controls (P < .001). Lower levels of STAT-5 phosphorylation after IL-7 stimulation were observed in both CD4 and CD8 T cells from patients with ICL, compared with controls (P < .001 and P = .017, respectively), that inversely correlated in CD4 T cells with serum IL-7 levels (r = -0.734, P = .013). Destabilization of p27(kip1), a critical step for IL-7-induced T-cell cycling, was decreased in patients with ICL, compared with controls (P = .004), after IL-7 stimulation. CONCLUSIONS: These data suggest that diminished responsiveness to IL-7 in CD4 and CD8 T cells during ICL may be contributing to the dysregulation of T-cell homeostasis.


Asunto(s)
Interleucina-7/sangre , Linfocitos T/inmunología , Linfocitopenia-T Idiopática CD4-Positiva/inmunología , Adulto , Femenino , Humanos , Interleucina-7/genética , Interleucina-7/inmunología , Leucocitos Mononucleares/metabolismo , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Fosforilación , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Interleucina-7/sangre , Receptores de Interleucina-7/genética , Receptores de Interleucina-7/inmunología , Factor de Transcripción STAT5/genética , Factor de Transcripción STAT5/metabolismo , Linfocitopenia-T Idiopática CD4-Positiva/metabolismo , Regulación hacia Arriba , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo
18.
AIDS ; 37(14): 2119-2130, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37555786

RESUMEN

OBJECTIVES: People with HIV-1 (PWH) on effective antiretroviral therapy (ART) continue to exhibit chronic systemic inflammation, immune activation, and persistent elevations in markers of HIV-1 infection [including HIV-DNA, cell-associated HIV-RNA (CA HIV-RNA), and antibodies to HIV-1 proteins] despite prolonged suppression of plasma HIV-RNA levels less than 50 copies/ml. Here, we investigated the hypothesis that nonreplicating but transcriptionally and translationally competent 'defective' HIV-1 proviruses may be one of drivers of these phenomena. DESIGN: A combined cohort of 23 viremic and virologically suppressed individuals on ART were studied. METHODS: HIV-DNA, CA HIV-RNA, western blot score (measure of anti-HIV-1 antibodies as a surrogate for viral protein expression in vivo ), and key biomarkers of inflammation and coagulation (IL-6, hsCRP, TNF-alpha, tissue factor, and D-dimer) were measured in peripheral blood and analyzed using a combined cross-sectional and longitudinal approaches. Sequences of HIV-DNA and CA HIV-RNA obtained via 5'-LTR-to-3'-LTR PCR and single-genome sequencing were also analyzed. RESULTS: We observed similar long-term persistence of multiple, unique, transcriptionally active 'defective' HIV-1 provirus clones (average: 11 years., range: 4-20 years) and antibody responses against HIV-1 viral proteins among all ART-treated participants evaluated. A direct correlation was observed between the magnitude of HIV-1 western blot score and the levels of transcription of 'defective' HIV-1 proviruses ( r  = 0.73, P  < 0.01). Additional correlations were noted between total CD8 + T-cell counts and HIV-DNA ( r  = 0.52, P  = 0.01) or CA HIV-RNA ( r  = 0.65, P  < 0.01). CONCLUSION: These findings suggest a novel interplay between transcription and translation of 'defective' HIV-1 proviruses and the persistent immune activation seen in the setting of treated chronic HIV-1 infection.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Humanos , Provirus/genética , VIH-1/fisiología , Estudios Transversales , Linfocitos T CD4-Positivos , ADN Viral , ARN Viral , Proteínas Virales , Inflamación
19.
Nat Med ; 29(6): 1364-1369, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37322122

RESUMEN

Reservoirs of HIV maintained in anatomic compartments during antiretroviral therapy prevent HIV eradication. However, mechanisms driving their persistence and interventions to control them remain elusive. Here we report the presence of an inducible HIV reservoir within antigen-specific CD4+T cells in the central nervous system of a 59-year-old male with progressive multifocal leukoencephalopathy immune reconstitution inflammatory syndrome (PML-IRIS). HIV production during PML-IRIS was suppressed by modulating inflammation with corticosteroids; selection of HIV drug resistance caused subsequent breakthrough viremia. Therefore, inflammation can influence the composition, distribution and induction of HIV reservoirs, warranting it as a key consideration for developing effective HIV remission strategies.


Asunto(s)
Infecciones por VIH , Síndrome Inflamatorio de Reconstitución Inmune , Leucoencefalopatía Multifocal Progresiva , Masculino , Humanos , Persona de Mediana Edad , Síndrome Inflamatorio de Reconstitución Inmune/tratamiento farmacológico , Síndrome Inflamatorio de Reconstitución Inmune/etiología , Leucoencefalopatía Multifocal Progresiva/tratamiento farmacológico , Leucoencefalopatía Multifocal Progresiva/etiología , Encéfalo , Sistema Nervioso Central
20.
J Infect Dis ; 203(6): 756-64, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21325137

RESUMEN

BACKGROUND: 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (statins) exhibit antiviral activity against human immunodeficiency virus type 1 (HIV-1) in vitro and may modulate the immune response to HIV infection. Studies evaluating the antiviral activity of statins have yielded conflicting results. METHODS: We conducted a randomized, double-blind, placebo-controlled crossover trial to investigate the effect of atorvastatin on HIV-1 RNA (primary objective) and cellular markers of immune activation (secondary objective). HIV-infected individuals not receiving antiretroviral therapy were randomized to receive either 8 weeks of atorvastatin (80 mg) or placebo daily. After a 4-6 week washout phase, participants switched treatment assignments. The study had 80% power to detect a 0.3 log(10) decrease in HIV-1 RNA level. Expression of CD38 and HLA-DR on CD4(+) and CD8(+) T cells was used to measure immune activation. RESULTS: Of 24 randomized participants, 22 completed the study. Although HIV-1 RNA level was unaffected by the intervention (-0.13 log(10) copies/mL; P = .85), atorvastatin use resulted in reductions in circulating proportions of CD4(+) HLA-DR(+) (-2.5%; P = .02), CD8(+) HLA-DR(+) (-5%; P = .006), and CD8(+) HLA-DR(+) CD38(+) T cells (-3%; P = .03). Reductions in immune activation did not correlate with declines in serum levels of low-density lipoprotein cholesterol. CONCLUSIONS: Short-term use of atorvastatin was associated with modest but statistically significant reductions in the proportion of activated T lymphocytes.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Ácidos Heptanoicos/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Pirroles/farmacología , ARN Viral/efectos de los fármacos , Adulto , Atorvastatina , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD8-positivos/efectos de los fármacos , Estudios Cruzados , Método Doble Ciego , Infecciones por VIH/sangre , VIH-1/genética , VIH-1/inmunología , Ácidos Heptanoicos/administración & dosificación , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Masculino , Placebos , Pirroles/administración & dosificación , ARN Viral/sangre
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