Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
PLoS Pathog ; 18(3): e1010369, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35303045

RESUMEN

Eliciting broadly neutralizing antibodies (bnAbs) is a cornerstone of HIV-1 vaccine strategies. Comparing HIV-1 envelope (env) sequences from the first weeks of infection to the breadth of antibody responses observed several years after infection can help define viral features critical to vaccine design. We investigated the relationship between HIV-1 env genetics and the development of neutralization breadth in 70 individuals enrolled in a prospective acute HIV-1 cohort. Half of the individuals who developed bnAbs were infected with multiple HIV-1 founder variants, whereas all individuals with limited neutralization breadth had been infected with single HIV-1 founders. Accordingly, at HIV-1 diagnosis, env diversity was significantly higher in participants who later developed bnAbs compared to those with limited breadth (p = 0.012). This association between founder multiplicity and the subsequent development of neutralization breadth was also observed in 56 placebo recipients in the RV144 vaccine efficacy trial. In addition, we found no evidence that neutralization breath was heritable when analyzing env sequences from the 126 participants. These results demonstrate that the presence of slightly different HIV-1 variants in acute infection could promote the induction of bnAbs, suggesting a novel vaccine strategy, whereby an initial immunization with a cocktail of minimally distant antigens would be able to initiate bnAb development towards breadth.


Asunto(s)
VIH-1 , Anticuerpos Neutralizantes , Epítopos , Anticuerpos Anti-VIH , VIH-1/genética , Humanos , Estudios Prospectivos , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética
2.
J Infect Dis ; 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37795976

RESUMEN

BACKGROUND: HVTN 120 is a phase 1/2a randomized double-blind placebo-controlled HIV vaccine trial that evaluated the safety and immunogenicity of ALVAC-HIV (vCP2438) and MF59- or AS01B-adjuvanted bivalent subtype C gp120 Env protein at two dose levels in healthy HIV-uninfected adults. Trial registration URL https://clinicaltrials.gov/ct2/show/NCT03122223 and registration number NCT03122223. METHODS: Participants received ALVAC-HIV (vCP2438) alone or placebo at months 0 and 1. At months 3 and 6, participants received either placebo, ALVAC-HIV (vCP2438) with 200µg of bivalent subtype C gp120 adjuvanted with MF59 or AS01B, or ALVAC-HIV (vCP2438) with 40µg of bivalent subtype C gp120 adjuvanted with AS01B. Primary outcomes were safety and immune responses. RESULTS: We enrolled 160 participants, 55% females, 18-40 years old (median age 24 years) of whom 150 received vaccine and 10 placebo. Vaccines were generally safe and well tolerated. At months 6.5 and 12, CD4+ T-cell response rates and magnitudes were higher in the AS01B-adjuvanted groups than in the MF59-adjuvanted group. At month 12, HIV-specific Env-gp120 binding antibody response magnitudes in the 40µg gp120/AS01B group were higher than in either of the 200µg gp120 groups. CONCLUSIONS: The 40µg dose gp120/AS01B regimen elicited the highest CD4+ T-cell and binding antibody responses.

3.
J Virol ; 95(17): e0079721, 2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34160251

RESUMEN

Identifying whether viral features present in acute HIV-1 infection predetermine the development of neutralization breadth is critical to vaccine design. Incorporating such features in vaccine antigens could initiate cross-reactive antibody responses that could sufficiently protect vaccinees from HIV-1 infection despite the uniqueness of each founder virus. To understand the relationship between Env determinants and the development of neutralization breadth, we focused on 197 individuals enrolled in two cohorts in Thailand and East Africa (RV144 and RV217) and followed since their diagnosis in acute or early HIV-1 infection. We analyzed the distribution of variable loop lengths and glycans, as well as the predicted density of the glycan shield, and compared these envelope features to the neutralization breadth data obtained 3 years after infection (n = 121). Our study revealed limited evidence for glycan shield features that associate with the development of neutralization breadth. While the glycan shield tended to be denser in participants who subsequently developed breadth, no significant relationship was found between the size of glycan holes and the development of neutralization breadth. The parallel analysis of 3,000 independent Env sequences showed no evidence of directional evolution of glycan shield features since the beginning of the epidemic. Together, our results highlight that glycan shield features in acute and early HIV-1 infection may not play a role determinant enough to dictate the development of neutralization breadth and instead suggest that the glycan shield's reactive properties that are associated with immune evasion may have a greater impact. IMPORTANCE A major goal of HIV-1 vaccine research is to design vaccine candidates that elicit potent broadly neutralizing antibodies (bNAbs). Different viral features have been associated with the development of bNAbs, including the glycan shield on the surface of the HIV-1 Envelope (Env). Here, we analyzed data from two cohorts of individuals who were followed from early infection to several years after infection spanning multiple HIV-1 subtypes. We compared Env glycan features in HIV-1 sequences obtained in early infection to the potency and breadth of neutralizing antibodies measured 1 to 3 years after infection. We found limited evidence of glycan shield properties that associate with the development of neutralization breadth in these cohorts. These results may have important implications for antigen design in future vaccine strategies and emphasize that HIV-1 vaccines will need to rely on a complex set of properties to elicit neutralization breadth.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/epidemiología , VIH-1/inmunología , Evasión Inmune/inmunología , Polisacáridos/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , África Oriental/epidemiología , Anticuerpos Neutralizantes/sangre , Estudios de Cohortes , Epítopos , Glicosilación , Anticuerpos Anti-VIH/sangre , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , Tailandia/epidemiología
4.
PLoS Pathog ; 16(2): e1008179, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32027734

RESUMEN

Most HIV-1 infected individuals do not know their infection dates. Precise infection timing is crucial information for studies that document transmission networks or drug levels at infection. To improve infection timing, we used the prospective RV217 cohort where the window when plasma viremia becomes detectable is narrow: the last negative visit occurred a median of four days before the first detectable HIV-1 viremia with an RNA test, referred below as diagnosis. We sequenced 1,280 HIV-1 genomes from 39 participants at a median of 4, 32 and 170 days post-diagnosis. HIV-1 infections were dated by using sequence-based methods and a viral load regression method. Bayesian coalescent and viral load regression estimated that infections occurred a median of 6 days prior to diagnosis (IQR: 9-3 and 11-4 days prior, respectively). Poisson-Fitter, which analyzes the distribution of hamming distances among sequences, estimated a median of 7 days prior to diagnosis (IQR: 15-4 days) based on sequences sampled 4 days post-diagnosis, but it did not yield plausible results using sequences sampled at 32 days. Fourteen participants reported a high-risk exposure event at a median of 8 days prior to diagnosis (IQR: 12 to 6 days prior). These different methods concurred that HIV-1 infection occurred about a week before detectable viremia, corresponding to 20 days (IQR: 34-15 days) before peak viral load. Together, our methods comparison helps define a framework for future dating studies in early HIV-1 infection.


Asunto(s)
Genoma Viral , Infecciones por VIH/diagnóstico , VIH-1/metabolismo , Técnicas de Diagnóstico Molecular , Carga Viral , Viremia/diagnóstico , Adulto , África Oriental , Femenino , Infecciones por VIH/genética , VIH-1/genética , Humanos , Masculino , Estudios Prospectivos , Tailandia , Factores de Tiempo , Viremia/genética
5.
PLoS Comput Biol ; 17(2): e1008537, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33524022

RESUMEN

While large datasets of HIV-1 sequences are increasingly being generated, many studies rely on a single gene or fragment of the genome and few comparative studies across genes have been done. We performed genome-based and gene-specific Bayesian phylogenetic analyses to investigate how certain factors impact estimates of the infection dates in an acute HIV-1 infection cohort, RV217. In this cohort, HIV-1 diagnosis corresponded to the first RNA positive test and occurred a median of four days after the last negative test, allowing us to compare timing estimates using BEAST to a narrow window of infection. We analyzed HIV-1 sequences sampled one week, one month and six months after HIV-1 diagnosis in 39 individuals. We found that shared diversity and temporal signal was limited in acute infection, and insufficient to allow timing inferences in the shortest HIV-1 genes, thus dated phylogenies were primarily analyzed for env, gag, pol and near full-length genomes. There was no one best-fitting model across participants and genes, though relaxed molecular clocks (73% of best-fitting models) and the Bayesian skyline (49%) tended to be favored. For infections with single founders, the infection date was estimated to be around one week pre-diagnosis for env (IQR: 3-9 days) and gag (IQR: 5-9 days), whilst the genome placed it at a median of 10 days (IQR: 4-19). Multiply-founded infections proved problematic to date. Our ability to compare timing inferences to precise estimates of HIV-1 infection (within a week) highlights that molecular dating methods can be applied to within-host datasets from early infection. Nonetheless, our results also suggest caution when using uniform clock and population models or short genes with limited information content.


Asunto(s)
Infecciones por VIH/epidemiología , VIH-1 , Modelos Biológicos , Programas Informáticos , Teorema de Bayes , Estudios de Cohortes , Biología Computacional , Femenino , Genes Virales , Variación Genética , Infecciones por VIH/diagnóstico , Infecciones por VIH/virología , VIH-1/genética , VIH-1/aislamiento & purificación , Humanos , Funciones de Verosimilitud , Estudios Longitudinales , Masculino , Modelos Genéticos , Filogenia , Factores de Tiempo
6.
Clin Infect Dis ; 72(1): 50-60, 2021 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-31900486

RESUMEN

BACKGROUND: The Pox-Protein Public-Private Partnership is performing a suite of trials to evaluate the bivalent subtype C envelope protein (TV1.C and 1086.C glycoprotein 120) vaccine in the context of different adjuvants and priming agents for human immunodeficiency virus (HIV) type 1 (HIV-1) prevention. METHODS: In the HIV Vaccine Trials Network 111 trial, we compared the safety and immunogenicity of DNA prime followed by DNA/protein boost with DNA/protein coadministration injected intramuscularly via either needle/syringe or a needle-free injection device (Biojector). One hundred thirty-two healthy, HIV-1-uninfected adults were enrolled from Zambia, South Africa, and Tanzania and were randomized to 1 of 6 arms: DNA prime, protein boost by needle/syringe; DNA and protein coadministration by needle/syringe; placebo by needle/syringe; DNA prime, protein boost with DNA given by Biojector; DNA and protein coadministration with DNA given by Biojector; and placebo by Biojector. RESULTS: All vaccinations were safe and well tolerated. DNA and protein coadministration was associated with increased HIV-1 V1/V2 antibody response rate, a known correlate of decreased HIV-1 infection risk. DNA administration by Biojector elicited significantly higher CD4+ T-cell response rates to HIV envelope protein than administration by needle/syringe in the prime/boost regimen (85.7% vs 55.6%; P = .02), but not in the coadministration regimen (43.3% vs 48.3%; P = .61). CONCLUSIONS: Both the prime/boost and coadministration regimens are safe and may be promising for advancement into efficacy trials depending on whether cellular or humoral responses are desired. CLINICAL TRIALS REGISTRATION: South African National Clinical Trials Registry (application 3947; Department of Health [DoH] no. DOH-27-0715-4917) and ClinicalTrials.gov (NCT02997969).


Asunto(s)
Vacunas contra el SIDA , Infecciones por VIH , VIH-1 , Vacunas contra el SIDA/uso terapéutico , Adulto , ADN , Anticuerpos Anti-VIH , Infecciones por VIH/prevención & control , VIH-1/genética , Humanos , Inmunización Secundaria , Inmunogenicidad Vacunal , Polisorbatos , Sudáfrica , Escualeno , Tanzanía , Zambia
7.
AIDS Res Ther ; 18(1): 89, 2021 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-34823544

RESUMEN

BACKGROUND: Increased availability of HIV care over the past decade has dramatically reduced morbidity and mortality among people living with HIV (PLWH) in sub-Saharan Africa. However, perceived and experienced barriers to care, including dissatisfaction with services, may impact adherence and viral suppression. We examined the associations between satisfaction with HIV care and antiretroviral therapy (ART) adherence and viral load suppression. METHODS: The African Cohort Study (AFRICOS) is a prospective observational study conducted at PEPFAR-supported clinics in four African countries. At enrollment and twice-yearly study visits, participants received a clinical assessment and a socio-behavioral questionnaire was administered. Participants were classified as dissatisfied with care if they reported dissatisfaction with any of the following: waiting time, health care worker skills, health care worker attitudes, quality of clinic building, or overall quality of care received. Robust Poisson regression was used to estimate prevalence ratios and 95% confidence intervals (CIs) for associations between satisfaction with care and ART adherence and between satisfaction with care and viral suppression (viral load < 1000 copies/mL). RESULTS: As of 1 March 2020, 2928 PLWH were enrolled and 2311 had a year of follow-up visits. At the first annual follow-up visit, 2309 participants responded to questions regarding satisfaction with quality of care, and 2069 (89.6%) reported satisfaction with care. Dissatisfaction with waiting time was reported by 177 (7.6%), building quality by 59 (2.6%), overall quality of care by 18 (0.8%), health care worker attitudes by 16 (0.7%), and health care worker skills by 15 (0.7%). After adjusting for age and site, there was no significant difference in viral suppression between those who were satisfied with care and those who were dissatisfied (aPR: 1.03, 95% CI 0.97-1.09). Satisfaction with HIV care was moderately associated with ART adherence among AFRICOS participants (aPR: 1.09; 95% CI 1.00-1.16). CONCLUSIONS: While patient satisfaction in AFRICOS was high and the association between perceived quality of care and adherence to ART was marginal, we did identify potential target areas for HIV care improvement, including reducing clinic waiting times.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Fármacos Anti-VIH/uso terapéutico , Estudios de Cohortes , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Cumplimiento de la Medicación , Satisfacción Personal , Carga Viral
8.
PLoS Med ; 17(5): e1003117, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32442195

RESUMEN

BACKGROUND: DNA plasmids promise a pragmatic alternative to viral vectors for prime-boost HIV-1 vaccines. We evaluated DNA plasmid versus canarypox virus (ALVAC) primes in 2 randomized, double-blind, placebo-controlled trials in southern Africa with harmonized trial designs. HIV Vaccine Trials Network (HVTN) 111 tested DNA plasmid prime by needle or needleless injection device (Biojector) and DNA plasmid plus gp120 protein plus MF59 adjuvant boost. HVTN 100 tested ALVAC prime and ALVAC plus gp120 protein plus MF59 adjuvant boost (same protein/adjuvant as HVTN 111) by needle. METHODS AND FINDINGS: The primary endpoints for this analysis were binding antibody (bAb) responses to HIV antigens (gp120 from strains ZM96, 1086, and TV1; variable 1 and 2 [V1V2] regions of gp120 from strains TV1, 1086, and B.CaseA, as 1086 V1V2 and B.CaseA were correlates of risk in the RV144 efficacy trial), neutralizing antibody (nAb) responses to pseudoviruses TV1c8.2 and MW925.26, and cellular responses to vaccine-matched antigens (envelope [Env] from strains ZM96, 1086, and TV1; and Gag from strains LAI and ZM96) at month 6.5, two weeks after the fourth vaccination. Per-protocol cohorts included vaccine recipients from HVTN 100 (n = 186, 60% male, median age 23 years) enrolled between February 9, 2015, and May 26, 2015 and from HVTN 111 (n = 56, 48% male, median age 24 years) enrolled between June 21, 2016, and July 13, 2017. IgG bAb response rates were 100% to 3 Env gp120 antigens in both trials. Response rates to V1V2 were lower and similar in both trials except to vaccine-matched 1086 V1V2, with rates significantly higher for the DNA-primed regimen than the ALVAC-primed regimen: 96.6% versus 72.7% (difference = 23.9%, 95% CI 15.6%-32.2%, p < 0.001). Among positive responders, bAb net mean fluorescence intensity (MFI) was significantly higher with the DNA-primed regimen than ALVAC-primed for 1086 V1V2 (geometric mean [GM] 2,833.3 versus 1,200.9; ratio = 2.36, 95% CI 1.42-3.92, p < 0.001) and B.CaseA V1V2 (GM 2314.0 versus 744.6, ratio = 3.11, 95% CI 1.51-6.38, p = 0.002). nAb response rates were >98% in both trials, with significantly higher 50% inhibitory dilution (ID50) among DNA-primed positive responders (n = 53) versus ALVAC-primed (n = 182) to tier 1A MW965.26 (GM 577.7 versus 265.7, ratio = 2.17, 95% CI 1.67-2.83, p < 0.001) and to TV1c8.2 (GM 187.3 versus 100.4, ratio = 1.87, 95% CI 1.48-2.35, p < 0.001). CD4+ T-cell response rates were significantly higher with DNA plasmid prime via Biojector than ALVAC prime (91.4% versus 52.8%, difference = 38.6%, 95% CI 20.5%-56.6%, p < 0.001 for ZM96.C; 88.0% versus 43.1%, difference = 44.9%, 95% CI 26.7%-63.1%, p < 0.001 for 1086.C; 55.5% versus 2.2%, difference = 53.3%, 95% CI 23.9%-82.7%, p < 0.001 for Gag LAI/ZM96). The study's main limitations include the nonrandomized comparison of vaccines from 2 different trials, the lack of data on immune responses to other non-vaccine-matched antigens, and the uncertain clinical significance of the observed immunological effects. CONCLUSIONS: In this study, we found that further investigation of DNA/protein regimens is warranted given enhanced immunogenicity to the V1V2 correlates of decreased HIV-1 acquisition risk identified in RV144, the only HIV vaccine trial to date to show any efficacy.


Asunto(s)
Vacunas contra el SIDA/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Anti-VIH/inmunología , Adulto , Formación de Anticuerpos/inmunología , ADN/genética , Método Doble Ciego , Femenino , Vectores Genéticos , Antígenos VIH/inmunología , Infecciones por VIH/prevención & control , VIH-1/genética , VIH-1/inmunología , Humanos , Masculino , Plásmidos/genética , Vacunación/métodos , Adulto Joven
9.
J Virol ; 93(14)2019 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-31043532

RESUMEN

Acute HIV-1 infection is characterized by high viremia and massive depletion of CD4+ T cells throughout all tissue compartments. During this time the latent viral reservoir is established but the dynamics of memory CD4+ T cell subset development, their infectability and influence on disease progression during acute HIV-1 infection has not been carefully described. We therefore investigated the dynamics of CD4+ T cell memory populations in the RV217 (ECHO) cohort during the acute phase of infection. Interestingly, while we found only small changes in central or effector memory compartments, we observed a profound expansion of stem cell-like memory CD4+ T cells (SCM) (2.7-fold; P < 0.0001). Furthermore, we demonstrated that the HIV-1 integration and replication preferentially take place in highly differentiated CD4+ T cells such as transitional memory (TM) and effector memory (EM) CD4+ T cells, while naive and less mature memory cells prove to be more resistant. Despite the relatively low frequency of productively infected SCM, we suggest that their quiescent phenotype, increased susceptibility to HIV-1 integration compared to naive cells and extensive expansion make them one of the key players in establishment and persistence of the HIV-1 reservoir. Moreover, the expansion of SCM in acute HIV-1 infection was a result of Fas upregulation on the surface of naive CD4+ T cells. Interestingly, the upregulation of Fas receptor and expansion of SCM in acute HIV-1 infection was associated with the early viral set point and disease progression (rho = 0.47, P = 0.02, and rho = 0.42, P = 0.041, respectively). Taken together, our data demonstrate an expansion of SCM during early acute HIV-1 infection which is associated with disease outcome.IMPORTANCE Understanding the immunopathology of acute HIV-1 infection will help to develop eradication strategies. We demonstrate here that a CD4+ T cell memory subset expands during acute HIV-1 infection, which is associated with disease progression.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Memoria Inmunológica , Células Madre/inmunología , Regulación hacia Arriba/inmunología , Enfermedad Aguda , Linfocitos T CD4-Positivos/virología , Estudios de Cohortes , Femenino , Humanos , Masculino , Células Madre/virología , Viremia/inmunología
10.
Trop Med Int Health ; 25(5): 579-589, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31984634

RESUMEN

OBJECTIVE: Early identification of confirmed virological failure is paramount to avoid accumulation of drug resistance in patients on antiretroviral therapy (ART). Scale-up of HIV-RNA monitoring in Africa and timely switch to second-line regimens are challenged. METHODS: A WHO adapted confirmed virological treatment screening algorithm (HIV-RNA screening, enhanced adherence counselling, confirmatory HIV-RNA testing) was evaluated in HIV-infected patients on first-line ART from Tanzania. The main endpoints included viral resuppression and virological failure rates, retention and turnaround time of the screening algorithm until second-line ART initiation. Secondary endpoints included risk factors for virological treatment failure and patterns of genotypic drug resistance. RESULTS: HIV-RNA >1000 copies/ml at first screening was detected in 58/356 (16.3%) patients (median time-on-treatment 6.3 years, 25% immunological treatment failure). Adjusted risk factors for virological failure were age <30 years (RR 5.2 [95% CI: 2.5-10.8]), years on ART ≥3 years (RR 3.0 [1.0-8.9]), CD4-counts <200 cells/µl (RR 9.3 [4.0-21.8]) and poor self-reported treatment adherence (RR 2.0 [1.2-3.4]). Resuppression of HIV-RNA <1000 copies/ml was observed in 5/50 (10%) cases after enhanced adherence counselling. Confirmatory testing within 3 months was performed in only 46.6% and switch to second-line ART within 6 months in 60.4% of patients. Major NNRTI-mutation were detected in all of 30 patients, NRTI mutations in 96.7% and ≥3 thymidine-analogue mutations in 40%. No remaining NRTI options were predicted in 57% and limited susceptibility in 23% of patients. CONCLUSION: We observed low levels of viral resuppression following adherence counselling, associated with high levels of accumulated drug resistance. High visit burden and turnaround times for confirmed virological failure diagnosis further delayed switching to second-line treatment which could be improved using novel point-of-care viral load monitoring systems.


OBJECTIF: L'identification précoce de l'échec virologique confirmé est primordiale pour éviter l'accumulation de résistance aux médicaments chez les patients sous traitement antirétroviral (ART). L'intensification du suivi de l'ARN du VIH en Afrique et le passage en temps opportun aux schémas thérapeutiques de deuxième intention sont adressés. MÉTHODES: Nous avons évalué un algorithme adapté de l'OMS confirmé pour le dépistage du traitement virologique (dépistage de l'ARN du VIH, adhésion renforcée du conseil, test de confirmation de l'ARN du VIH) chez des patients infectés par le VIH sous ART de première intention en Tanzanie. Les critères principaux comprenaient la répression virale et les taux d'échec virologique, la rétention et et la durée de rotation de l'algorithme de dépistage jusqu'à l'initiation de l'ART de deuxième ligne. Les critères d'évaluation secondaires comprenaient les facteurs de risque d'échec du traitement virologique et les profils de résistance génotypique aux médicaments. RÉSULTATS: Un ARN-VIH >1000 copies/ml au premier dépistage a été détecté chez 58/356 (16,3%) patients (durée médiane de traitement de 6,3 ans, 25% d'échec immunologique du traitement). Les facteurs de risque ajustés pour l'échec virologique étaient l'âge <30 ans (RR: 5,2 [IC95%: 2,5-10,8]), les années sous ART ≥3 ans (RR: 3,0 [1,0-8,9]), la numération des CD4 <200 cellules/µL (RR: 9,3 [4,0-21,8]) et une mauvaise compliance au traitement autodéclarée (RR: 2,0 [1,2-3,4]). Une re-suppression du VIH-ARN <1000 copies/mL a été observée chez 5/50 (10%) des cas après renforcement du conseil pour la compliance. Un test de confirmation dans les 3 mois n'a été réalisé que dans 46,6% des cas et le passage à l'ART de deuxième ligne dans les 6 mois chez 60,4% des patients. Des mutations NNRTI majeures ont été détectées chez tous les 30 patients, des mutations NRTI chez 96,7% et ≥3 mutations analogues à la thymidine chez 40%. Aucune option NRTI restante n'a été prévue chez 57% des cas et une sensibilité limitée chez 23% des patients. CONCLUSION: Nous avons observé de faibles taux de re-suppression virale après des conseils d'adhésion, associés à des taux élevés de résistance accumulée aux médicaments. La charge élevée des visites et les délais de rotation pour le diagnostic confirmé d'échec virologique ont retardé le passage au traitement de deuxième intention, ce qui pourrait être amélioré à l'aide de nouveaux systèmes de surveillance de la charge virale au point des soins.


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/epidemiología , VIH-1 , Cumplimiento de la Medicación/psicología , Adulto , Algoritmos , Recuento de Linfocito CD4 , Consejo , Monitoreo de Drogas , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Cumplimiento de la Medicación/estadística & datos numéricos , Persona de Mediana Edad , Tanzanía/epidemiología , Carga Viral
11.
AIDS Res Ther ; 17(1): 66, 2020 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-33183355

RESUMEN

INTRODUCTION: With increased use of antiretroviral therapy (ART), HIV mortality rates are declining and people living with HIV (PLWH) are surviving longer. We characterized CD4 recovery and viral suppression among adults aged < 50 and ≥ 50 years living with HIV who initiated ART in the African Cohort Study (AFRICOS). METHODS: Beginning in January 2013, PLWH at twelve clinics in Kenya, Uganda, Tanzania and Nigeria underwent medical history review, CD4 and viral load testing as part of the ongoing African Cohort Study (AFRICOS). ART-naïve PLWH who initiated ART within 30 days of enrollment and had at least one year of follow-up were included in these analyses. To compare ART response in participants < 50 years and ≥ 50 years old, changes in CD4 count and viral load suppression after ART initiation were examined at different time points using linear and binomial regression with generalized estimating equations. Variables for time since ART initiation and the interaction between age group and time on ART were included in the model to evaluate longitudinal changes in CD4 recovery and viral suppression by age. RESULTS: Between January 2013 and September 2019, 2918 PLHV were enrolled in the cohort. Of these, 443 were ART naïve and initiated on ART within 30 days of enrollment, with 90% (n = 399) aged < 50 years old at ART initiation. At ART initiation, participants aged 50 and older had a higher median CD4 count compared to participants younger than 50 years of age although it did not reach statistical significance (306 cells/mm3, IQR:130-547 vs. 277cells/mm3, IQR: 132-437). In adjusted models examining CD4 recovery and viral suppression there were no significant differences by age group over time. By the end of follow-up viral suppression was high among both groups of adults (96% of adults ≥ 50 years old and 92% of adults < 50 years old). CONCLUSION: This study found no difference in long-term CD4 recovery or viral suppression by age at ART initiation. We found that particularly among younger adults participants had lower median CD4 counts at ART initiation, suggesting the importance of identifying and putting this population on treatment earlier in the disease course.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Adulto , Anciano , Fármacos Anti-VIH/uso terapéutico , Recuento de Linfocito CD4 , Estudios de Cohortes , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Kenia , Persona de Mediana Edad , Carga Viral
12.
Clin Infect Dis ; 69(5): 805-812, 2019 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-30462188

RESUMEN

BACKGROUND: World Health Organization (WHO) guidelines identify human immunodeficiency virus (HIV) viral load <1000 copies/mL as the goal of antiretroviral therapy (ART). However, the clinical implications of viremia below this threshold are unclear in the African context. We examined factors associated with persistent low-level viremia (pLLV) and quantified the risk of subsequent virologic. METHODS: The African Cohort Study enrolled HIV-infected adults at clinics in Uganda, Kenya, Tanzania, and Nigeria, with assessments every 6 months. We evaluated participants prescribed ART for at least 6 months without virologic failure for pLLV. We used multinomial logistic regression to evaluate associations between prespecified factors of interest and 3 levels of pLLV (<200, 200-499, and 500-999 copies/mL). We used Anderson-Gill extended Cox proportional hazards to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for viremia category associations with time to failure. RESULTS: We included 1511 participants with 4382 person-years of follow-up. PLLV <200 copies/mL was observed at 20% of visits while 2% of visits had pLLV 200-499 and 500-999 copies/mL each, with substantial variation by site. Protease inhibitor-containing ART was associated with increased risk of pLLV. Compared to undetectable viral load, pLLV ≥200 copies/mL doubled the risk of developing virologic failure (pLLV 200-499: HR, 1.81 [95% CI, 1.08-3.02]); pLLV 500-999: HR, 2.36 [95% CI, 1.52-3.67]). CONCLUSIONS: Participants with pLLV ≥200 copies/mL were at increased risk of subsequent virologic failure. Optimized HIV care in this setting should target viral suppression <200 copies/mL.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Carga Viral , Viremia/tratamiento farmacológico , Adulto , África/epidemiología , Femenino , Infecciones por VIH/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Insuficiencia del Tratamiento , Viremia/epidemiología , Organización Mundial de la Salud , Adulto Joven
13.
Clin Infect Dis ; 69(4): 639-647, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30476001

RESUMEN

BACKGROUND: Noninfectious comorbid diseases (NCDs) contribute to morbidity and mortality in human immunodeficiency virus (HIV)-infected populations in resource-rich countries. With antiretroviral therapy (ART) scale-up in Africa, understanding burden NCD informs public health strategy. METHODS: At enrollment, participants at 11 HIV clinics in Kenya, Uganda, Tanzania, and Nigeria underwent medical history, physical, laboratory, and neuropsychological assessments to identify elevated blood pressure, hypercholesterolemia, dysglycemia, renal insufficiency, and cognitive impairment. Poisson regression models estimated adjusted relative risks (ARRs) and 95% confidence intervals (CIs) for the number of NCDs associated with factors of interest. Logistic regression was used to evaluate each NCD separately among HIV-infected participants. RESULTS: Among 2720 participants with complete NCD data, 2159 (79.4%) were HIV-infected. Of those, 1426 (66.0%) were taking ART and 813 (37.7%) had at least 1 NCD. HIV infection was associated with more NCDs, especially with ART (ARR, 1.42; 95% CI, 1.22-1.66). In addition to age, body mass index, and program site, ART usage was associated with more NCDs (ARR, 1.50; 95% CI, 1.27-1.78 for virologically suppressed and ARR, 1.38; 95% CI, 1.13-1.68 for viremic) among HIV-infected participants. In participants taking ART, CD4 nadir below 200 cells/mm3 was associated with more NCDs (ARR, 1.43; 95% CI, 1.06-1.93). ART use was independently associated with hypercholesterolemia and dysglycemia. Program site was significantly associated with all comorbidities except renal insufficiency. CONCLUSIONS: HIV infection was a risk for NCDs, which were common in HIV-infected participants, geographically variable, and largely consistent with metabolic complications of first-line ART.


Asunto(s)
Infecciones por VIH/epidemiología , Enfermedades no Transmisibles/epidemiología , Adulto , África del Sur del Sahara , Comorbilidad , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad
14.
N Engl J Med ; 374(22): 2120-30, 2016 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-27192360

RESUMEN

BACKGROUND: Acute human immunodeficiency virus type 1 (HIV-1) infection is a major contributor to transmission of HIV-1. An understanding of acute HIV-1 infection may be important in the development of treatment strategies to eradicate HIV-1 or achieve a functional cure. METHODS: We performed twice-weekly qualitative plasma HIV-1 RNA nucleic acid testing in 2276 volunteers who were at high risk for HIV-1 infection. For participants in whom acute HIV-1 infection was detected, clinical observations, quantitative measurements of plasma HIV-1 RNA levels (to assess viremia) and HIV antibodies, and results of immunophenotyping of lymphocytes were obtained twice weekly. RESULTS: Fifty of 112 volunteers with acute HIV-1 infection had two or more blood samples collected before HIV-1 antibodies were detected. The median peak viremia (6.7 log10 copies per milliliter) occurred 13 days after the first sample showed reactivity on nucleic acid testing. Reactivity on an enzyme immunoassay occurred at a median of 14 days. The nadir of viremia (4.3 log10 copies per milliliter) occurred at a median of 31 days and was nearly equivalent to the viral-load set point, the steady-state viremia that persists durably after resolution of acute viremia (median plasma HIV-1 RNA level, 4.4 log10 copies per milliliter). The peak viremia and downslope were correlated with the viral-load set point. Clinical manifestations of acute HIV-1 infection were most common just before and at the time of peak viremia. A median of one symptom of acute HIV-1 infection was recorded at a median of two study visits, and a median of one sign of acute HIV-1 infection was recorded at a median of three visits. CONCLUSIONS: The viral-load set point occurred at a median of 31 days after the first detection of plasma viremia and correlated with peak viremia. Few symptoms and signs were observed during acute HIV-1 infection, and they were most common before peak viremia. (Funded by the Department of Defense and the National Institute of Allergy and Infectious Diseases.).


Asunto(s)
Infecciones por VIH/diagnóstico , VIH-1 , Viremia/diagnóstico , Adolescente , Adulto , África Oriental , Anticuerpos Antivirales/sangre , Recuento de Linfocito CD4 , Progresión de la Enfermedad , Femenino , Infecciones por VIH/virología , VIH-1/genética , VIH-1/inmunología , VIH-1/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , ARN Viral/sangre , Tailandia , Carga Viral
15.
PLoS Pathog ; 13(7): e1006510, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28759651

RESUMEN

In order to inform the rational design of HIV-1 preventive and cure interventions it is critical to understand the events occurring during acute HIV-1 infection (AHI). Using viral deep sequencing on six participants from the early capture acute infection RV217 cohort, we have studied HIV-1 evolution in plasma collected twice weekly during the first weeks following the advent of viremia. The analysis of infections established by multiple transmitted/founder (T/F) viruses revealed novel viral profiles that included: a) the low-level persistence of minor T/F variants, b) the rapid replacement of the major T/F by a minor T/F, and c) an initial expansion of the minor T/F followed by a quick collapse of the same minor T/F to low frequency. In most participants, cytotoxic T-lymphocyte (CTL) escape was first detected at the end of peak viremia downslope, proceeded at higher rates than previously measured in HIV-1 infection, and usually occurred through the exploration of multiple mutational pathways within an epitope. The rapid emergence of CTL escape variants suggests a strong and early CTL response. Minor T/F viral strains can contribute to rapid and varied profiles of HIV-1 quasispecies evolution during AHI. Overall, our results demonstrate that early, deep, and frequent sampling is needed to investigate viral/host interaction during AHI, which could help identify prerequisites for prevention and cure of HIV-1 infection.


Asunto(s)
Infecciones por VIH/virología , VIH-1/genética , VIH-1/aislamiento & purificación , Adolescente , Adulto , Estudios de Cohortes , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/transmisión , VIH-1/clasificación , VIH-1/fisiología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Evasión Inmune , Masculino , Persona de Mediana Edad , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/virología , Adulto Joven
17.
PLoS Pathog ; 12(8): e1005805, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27486665

RESUMEN

The loss of HIV-specific CD8+ T cell cytolytic function is a primary factor underlying progressive HIV infection, but whether HIV-specific CD8+ T cells initially possess cytolytic effector capacity, and when and why this may be lost during infection, is unclear. Here, we assessed CD8+ T cell functional evolution from primary to chronic HIV infection. We observed a profound expansion of perforin+ CD8+ T cells immediately following HIV infection that quickly waned after acute viremia resolution. Selective expression of the effector-associated transcription factors T-bet and eomesodermin in cytokine-producing HIV-specific CD8+ T cells differentiated HIV-specific from bulk memory CD8+ T cell effector expansion. As infection progressed expression of perforin was maintained in HIV-specific CD8+ T cells with high levels of T-bet, but not necessarily in the population of T-betLo HIV-specific CD8+ T cells that expand as infection progresses. Together, these data demonstrate that while HIV-specific CD8+ T cells in acute HIV infection initially possess cytolytic potential, progressive transcriptional dysregulation leads to the reduced CD8+ T cell perforin expression characteristic of chronic HIV infection.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Proliferación Celular , Infecciones por VIH/inmunología , Inmunidad Celular , Adulto , Linfocitos T CD8-positivos/patología , Enfermedad Crónica , Femenino , Infecciones por VIH/patología , Humanos , Masculino , Persona de Mediana Edad , Perforina/inmunología , Proteínas de Dominio T Box/inmunología
18.
Lancet ; 388(10054): 1912-1920, 2016 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-27495354

RESUMEN

BACKGROUND: The past decades have seen an ongoing controversial debate about whether the immune activation induced by helminths has an effect on the susceptibility of individuals to HIV. In view of this, we assessed the effect of lymphatic filariasis, a chronic helminth disease elicited by Wuchereria bancrofti, on HIV incidence in southwest Tanzania. METHODS: In this population-based cohort study, we enrolled a geographically stratified randomly chosen sample of about 10% of the households in nine distinct sites in southwest Tanzania. All household members present were followed up and tested for HIV and circulating filarial antigen, an indicator of W bancrofti adult worm burden. Our main outcome of interest was HIV incidence in participants with or without lymphatic filariasis. FINDINGS: Between May 29, 2006, and June 16, 2011, we enrolled 4283 households with roughly 18 000 participants. Of these, 2699 individuals from Kyela district participated in at least one round of the EMINI study. In the 1055 initially HIV-negative adolescents and adults with clearly defined lymphatic filariasis status, 32 new HIV infections were observed in 2626 person-years. HIV incidence in lymphatic filariasis-positive participants (1·91 cases per 100 person-years) was significantly higher than the incidence in lymphatic filariasis-negative participants (0·80 cases per 100 person-years). The age-adjusted and sex-adjusted incidence rate ratio was 2·17 (95% CI 1·08-4·37, p=0·0300). Lymphatic filariasis status remained an independent and significantly relevant risk factor for HIV infection when controlled for other known risk factors such as sexual behaviour and socioeconomic factors. INTERPRETATION: To our knowledge, this is the first prospective study demonstrating a significantly increased risk of acquiring HIV for lymphatic filariasis-infected individuals. Immunological studies and interventional treatment studies that eliminate the adult worms and not only the microfilariae are needed to follow up on the results presented. FUNDING: European Union as part of EuropAid; German Federal Ministry of Education and Research; German Center for Infection Research.


Asunto(s)
Antígenos Helmínticos/sangre , Filariasis Linfática/epidemiología , Filariasis Linfática/inmunología , Enfermedades Endémicas , Infecciones por VIH/epidemiología , Infecciones por VIH/inmunología , Wuchereria bancrofti/inmunología , Adolescente , Adulto , Animales , Circuncisión Masculina , Enfermedades Endémicas/estadística & datos numéricos , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Incidencia , Masculino , Estado Civil , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Muestreo , Parejas Sexuales , Tanzanía/epidemiología , Wuchereria bancrofti/aislamiento & purificación
19.
J Virol ; 90(8): 4005-4016, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26842474

RESUMEN

UNLABELLED: Attrition within the CD4(+)T cell compartment, high viremia, and a cytokine storm characterize the early days after HIV infection. When the first emerging HIV-specific CD8(+)T cell responses gain control over viral replication it is incomplete, and clearance of HIV infection is not achieved even in the rare cases of individuals who spontaneously control viral replication to nearly immeasurably low levels. Thus, despite their partial ability to control viremia, HIV-specific CD8(+)T cell responses are insufficient to clear HIV infection. Studying individuals in the first few days of acute HIV infection, we detected the emergence of a unique population of CD38(+)CD27(-)CD8(+)T cells characterized by the low expression of the CD8 receptor (CD8(dim)). Interestingly, while high frequencies of HIV-specific CD8(+)T cell responses occur within the CD38(+)CD27(-)CD8(dim)T cell population, the minority populations of CD8(bright)T cells are significantly more effective in inhibiting HIV replication. Furthermore, the frequency of CD8(dim)T cells directly correlates with viral load and clinical predictors of more rapid disease progression. We found that a canonical burst of proliferative cytokines coincides with the emergence of CD8(dim)T cells, and the size of this population inversely correlates with the acute loss of CD4(+)T cells. These data indicate, for the first time, that early CD4(+)T cell loss coincides with the expansion of a functionally impaired HIV-specific CD8(dim)T cell population less efficient in controlling HIV viremia. IMPORTANCE: A distinct population of activated CD8(+)T cells appears during acute HIV infection with diminished capacity to inhibit HIV replication and is predictive of viral set point, offering the first immunologic evidence of CD8(+)T cell dysfunction during acute infection.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/inmunología , Enfermedad Aguda , Adolescente , Adulto , Linfocitos T CD4-Positivos/inmunología , Proliferación Celular , Epítopos , Femenino , Infecciones por VIH/virología , Humanos , Inmunofenotipificación , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Subgrupos de Linfocitos T/inmunología , Carga Viral , Replicación Viral , Adulto Joven
20.
PLOS Glob Public Health ; 4(4): e0002794, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38662685

RESUMEN

Alcohol misuse is a global concern, contributing to 5.3% of total deaths and 132.6 million disability-adjusted life years worldwide. In Sub-Saharan African countries, the prevalence of Alcohol Use Disorder (AUD) has risen, especially among female sex workers, due to increased availability and advertising. However, there are limited studies on alcohol use and AUD among female sex workers in Tanzania. This study aimed to determine the prevalence, patterns, and factors associated with alcohol use and AUD among sex workers in Mbeya city, Tanzania. In this cross-sectional study, 212 female sex workers in Mbeya city, Tanzania, seeking enrolment in the National Institute for Medical Research Mbeya Medical Research Centre's registration cohort from July to November 2022. Structured interviews covered socio-demographics, alcohol screening (AUDIT-C and Timeline Follow Back Calendar), and sexual behaviours data. Data were analysed using Stata version 17. Descriptive analysis assessed alcohol consumption and AUD prevalence. Factors associated with alcohol use and AUD at bivariate analysis were identified using Chi-square/Fisher's exact tests. All variables with p-value ≤ 0.20 were entered into a multivariable logistic regression model to identify factors associated with alcohol use and AUD. Among 212 participants, 86.6% reported alcohol use in the past 12 months, 85% in the past 30 days, and 98.5% met AUD criteria. Factors linked to recent alcohol consumption included primary education or higher, income above the median, and more than 10 sexual partners. Education level, marital status, income, and having dependents were significantly associated with heavy drinking episodes. The prevalence of AUD, alcohol use, and heavy episodic drinking were high among female sex workers in Mbeya city. Socio-demographic factors and risky sexual behaviours were associated with alcohol use and heavy episodic drinking highlighting the need for targeted interventions to combat alcohol abuse among female sex workers within the HIV program.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA