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2.
J Virol ; 97(12): e0187022, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-37991365

RESUMEN

IMPORTANCE: Twenty-five years after the first report that HIV-2 infection can reduce HIV-1-associated pathogenesis in dual-infected patients, the mechanisms are still not well understood. We explored these mechanisms in cell culture and showed first that these viruses can co-infect individual cells. Under specific conditions, HIV-2 inhibits HIV-1 through two distinct mechanisms, a broad-spectrum interferon response and an HIV-1-specific inhibition conferred by the HIV-2 TAR. The former could play a prominent role in dually infected individuals, whereas the latter targets HIV-1 promoter activity through competition for HIV-1 Tat binding when the same target cell is dually infected. That mechanism suppresses HIV-1 transcription by stalling RNA polymerase II complexes at the promoter through a minimal inhibitory region within the HIV-2 TAR. This work delineates the sequence of appearance and the modus operandi of each mechanism.


Asunto(s)
Coinfección , Regulación Viral de la Expresión Génica , Duplicado del Terminal Largo de VIH , VIH-1 , VIH-2 , Interferones , ARN Viral , Productos del Gen tat del Virus de la Inmunodeficiencia Humana , Humanos , Coinfección/inmunología , Coinfección/virología , Duplicado del Terminal Largo de VIH/genética , VIH-1/genética , VIH-1/inmunología , VIH-2/genética , VIH-2/inmunología , VIH-2/metabolismo , ARN Viral/genética , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/metabolismo , Interferones/inmunología , Regiones Promotoras Genéticas/genética , Unión Competitiva , ARN Polimerasa II/metabolismo , Transcripción Genética
3.
Viruses ; 11(7)2019 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-31319455

RESUMEN

Moloney leukemia virus 10 (MOV10) is an RNA helicase that has been shown to affect the replication of several viruses. The effect of MOV10 on Hepatitis B virus (HBV) infection is not known and its role on the replication of this virus is poorly understood. We investigated the effect of MOV10 down-regulation and MOV10 over-expression on HBV in a variety of cell lines, as well as in an infection system using a replication competent virus. We report that MOV10 down-regulation, using siRNA, shRNA, and CRISPR/Cas9 gene editing technology, resulted in increased levels of HBV DNA, HBV pre-genomic RNA, and HBV core protein. In contrast, MOV10 over-expression reduced HBV DNA, HBV pre-genomic RNA, and HBV core protein. These effects were consistent in all tested cell lines, providing strong evidence for the involvement of MOV10 in the HBV life cycle. We demonstrated that MOV10 does not interact with HBV-core. However, MOV10 binds HBV pgRNA and this interaction does not affect HBV pgRNA decay rate. We conclude that the restriction of HBV by MOV10 is mediated through effects at the level of viral RNA.


Asunto(s)
Virus de la Hepatitis B/fisiología , Hepatitis B/virología , Interacciones Huésped-Patógeno , Interacciones Microbianas , Virus de la Leucemia Murina de Moloney/fisiología , Replicación Viral , Animales , Línea Celular , Células Cultivadas , Regulación Viral de la Expresión Génica , Humanos , Ratones , Unión Proteica , ARN , ARN Helicasas/metabolismo , ARN Viral , Proteínas Virales/metabolismo
4.
Nat Commun ; 8(1): 1882, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-29192235

RESUMEN

Technical limitations in simultaneous microscopic visualization of RNA, DNA, and proteins of HIV have curtailed progress in this field. To address this need we develop a microscopy approach, multiplex immunofluorescent cell-based detection of DNA, RNA and Protein (MICDDRP), which is based on branched DNA in situ hybridization technology. MICDDRP enables simultaneous single-cell visualization of HIV (a) spliced and unspliced RNA, (b) cytoplasmic and nuclear DNA, and (c) Gag. We use MICDDRP to visualize incoming capsid cores containing RNA and/or nascent DNA and follow reverse transcription kinetics. We also report transcriptional "bursts" of nascent RNA from integrated proviral DNA, and concomitant HIV-1, HIV-2 transcription in co-infected cells. MICDDRP can be used to simultaneously detect multiple viral nucleic acid intermediates, characterize the effects of host factors or drugs on steps of the HIV life cycle, or its reactivation from the latent state, thus facilitating the development of antivirals and latency reactivating agents.


Asunto(s)
ADN Viral/química , ADN Viral/metabolismo , Fluoroinmunoensayo/métodos , VIH-1/química , ARN Viral/química , Línea Celular , Núcleo Celular/química , Núcleo Celular/virología , ADN Viral/genética , Infecciones por VIH/virología , VIH-1/genética , VIH-1/metabolismo , Humanos , Empalme del ARN , ARN Viral/genética , ARN Viral/metabolismo , Proteínas Virales/química , Proteínas Virales/genética , Proteínas Virales/metabolismo
5.
SAHARA J ; 11: 148-57, 2014.
Artículo en Francés | MEDLINE | ID: mdl-25088574

RESUMEN

PROBLEM: HIV testing in children had rarely been a central concern for researchers. When pediatric tracking retained the attention, it was more to inform on the diagnosis tools' performances rather than the fact the pediatric test can be accepted or refused. This article highlights the parents' reasons which explain why pediatric HIV test is accepted or refused. OBJECTIVE: To study among parents, the explanatory factors of the acceptability of pediatric HIV testing among infant less than six months. METHODS: Semi-structured interview with repeated passages in the parents of infants less than six months attending in health care facilities for the pediatric weighing/vaccination and consultations. RESULTS: We highlight that the parents' acceptance of the pediatric HIV screening is based on three elements. Firstly, the health care workers by his speech (which indicates its own knowledge and perceptions on the infection) directed towards mothers' influences their acceptance or not of the HIV test. Secondly, the mother who by her knowledge and perceptions on HIV, whose particular status, give an impression of her own wellbeing for her and her child influences any acceptance of the pediatric HIV test. Thirdly, the marital environment of the mother, particularly characterized by the ease of communication within the couple, to speak about the HIV test and its realization for the parents or the mother only are many factors which influence the effective realization of the pediatric HIV testing. The preventive principle of HIV transmission and the desire to realize the test in the newborn are not enough alone to lead to its effective realization, according to certain mothers confronted with the father's refusal. On the other hand, the other mothers refusing the realization of the pediatric test told to be opposed to it; of course, even if their partner would accept it. DISCUSSION: The mothers are the principal facing the pediatric HIV question and fear the reprimands and stigma. The father, the partner could be an obstacle, when he is opposed to the infant HIV testing, or also the facilitator with his realization if he is convinced. The father position thus remains essential face to the question of pediatric HIV testing acceptability. The mothers are aware of this and predict the difficulties of achieving their infant to be tested without the preliminary opinion of their partner at the same time father, and head of the family. CONCLUSION: The issue of pediatric HIV testing, at the end of our analysis, highlights three elements which require a comprehensive management to improve the coverage of pediatric HIV test. These three elements would not exist without being influenced; therefore they are constantly in interaction and prevent or support the realization or not pediatric test. Also, with the aim to improve the pediatric HIV test coverage, it is necessary to take into account the harmonious management of these elements. Firstly, the mother alone (with her knowledge, and perceptions), its marital environment (with the proposal of the HIV test integrating (1) the partner and/or father with his perceptions and knowledge on HIV infection and (2) facility of speaking about the test and its realization at both or one about the parents, the mother) and of the knowledge, attitudes and practices about the infection of health care workers of the sanitary institution. RECOMMENDATIONS: Our recommendations proposed taking into account a redefinition of the HIV/AIDS approach towards the families exposed to HIV and a more accentuated integration of the father facilitating their own HIV test acceptation and that of his child.


Asunto(s)
Serodiagnóstico del SIDA , Aceptación de la Atención de Salud , Serodiagnóstico del SIDA/métodos , Côte d'Ivoire/epidemiología , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Lactante , Recién Nacido , Entrevistas como Asunto , Masculino , Motivación , Padres/psicología , Estereotipo
6.
J Virol Methods ; 193(2): 439-45, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23872283

RESUMEN

This study evaluates HIV infant diagnosis on DBS using Biocentric HIV1-DNA and HIV1-RNA assays, in field conditions in Côte d'Ivoire. Paediatric screening was offered to children≤3 years in clinical sites in Côte d'Ivoire in 2008. For each HIV-infected child, two non-infected children were included and blood samples were collected. HIV-DNA results obtained on EDTA blood samples with Biocentric assay were the reference for HIV infant diagnosis. Plasma and DBS viral loads were measured using HIV-RNA Biocentric assay. DBS samples were also tested for HIV-DNA detection using both Biocentric and Amplicor Roche assays. Sensitivity, specificity and concordance between tests were calculated. Overall samples from 138 HIV-exposed children, 46 infected, 92 non-infected were included. All tests were 100% sensitive and specific including 100% concordance with the two HIV-DNA assays. The median level of HIV-DNA on EDTA samples was 3.15 log10 copies/10(6) PBMCs; the median level of HIV RNA in plasma and DBS were respectively 5.82 and 5.17 log10 copies/ml (Pearson's correlation R2=0.92, p<0.0001). The threshold for detectable HIV-RNA on DBS was 3.3 log10. Although there are differences between viral load measured on DBS and plasma, the two Biocentric assays present very good performances for HIV infant diagnosis on DBS while cheap and feasible.


Asunto(s)
Sangre/virología , ADN Viral/aislamiento & purificación , Infecciones por VIH/diagnóstico , VIH-1/aislamiento & purificación , Técnicas de Diagnóstico Molecular/métodos , ARN Viral/aislamiento & purificación , Manejo de Especímenes/métodos , Preescolar , Côte d'Ivoire , ADN Viral/genética , Desecación , Infecciones por VIH/virología , VIH-1/genética , Humanos , Lactante , Plasma/virología , ARN Viral/genética , Sensibilidad y Especificidad , Carga Viral/métodos
7.
J Acquir Immune Defic Syndr ; 64(2): 211-9, 2013 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-23797690

RESUMEN

BACKGROUND: In sub-Saharan Africa, most HIV-infected patients receive antiretroviral therapy (ART) without virological monitoring. Longitudinal data on secondary resistance are rare. METHODS: We conducted a prospective cohort study of HIV-1-infected adults initiating ART in 3 clinics using computerized monitoring systems. Patients had plasma HIV-1 RNA viral load (VL) tests at months 12 (M12) and 24 (M24) after ART initiation and HIV-1 resistance genotype tests if VL was detectable (≥300 copies/mL). RESULTS: Overall, 1573 patients initiated ART with stavudine/zidovudine plus lamivudine plus nevirapine/efavirenz. At M12 and M24, 944 and 844 patients, respectively, remained in active follow-up. Among them, 25% (M12) and 27% (M24) had detectable VLs and 12% (M12) and 19% (M24) had virus resistant to at least 1 antiretroviral drug, accounting for 54% (M12) and 75% (M24) of patients with detectable VLs. Among the resistant strains, 95% (M12) and 97% (M24) were resistant to lamivudine/emtricitabine, efavirenz, and/or nevirapine, the frequency of thymidine analog mutations increased from 8.1% (M12) to 14.7% (M24) and etravirine resistance increased from 13.5% (M12) to 24.5% (M24). CONCLUSIONS: Of the patients with detectable VLs at M24, 25% still did not harbor resistant virus. Preventing mutations from emerging with adherence reinforcement in patients with detectable VLs remains important beyond M24. Switching therapy early in patients with resistance to 3 TC/FTC and/or to nonnucleoside reverse transcriptase inhibitors to prevent extended resistance to nucleoside reverse transcriptase inhibitors and etravirine resistance from occurring is also a major challenge.


Asunto(s)
Fármacos Anti-VIH/farmacología , Farmacorresistencia Viral/genética , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Mutación , Piridazinas/farmacología , Timidina/análogos & derivados , Adulto , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/uso terapéutico , Estudios de Cohortes , Côte d'Ivoire , Monitoreo de Drogas/métodos , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , VIH-1/genética , Humanos , Masculino , Nitrilos , Estudios Prospectivos , Piridazinas/administración & dosificación , Piridazinas/uso terapéutico , Pirimidinas , ARN Viral/sangre , Inhibidores de la Transcriptasa Inversa/administración & dosificación , Inhibidores de la Transcriptasa Inversa/farmacología , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Timidina/farmacología , Factores de Tiempo , Carga Viral
8.
AIDS ; 25(6): 819-23, 2011 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-21412060

RESUMEN

BACKGROUND: WHO recommends initiating combination antiretroviral treatment at the minimal CD4 cell threshold of 350 cells/µl. In sub-Saharan Africa, the time for a recently infected patient to reach this threshold is unclear. METHOD: We estimated the probability of reaching different CD4 cell thresholds over time in the ANRS 1220 cohort of HIV-1 seroconverters in Côte d'Ivoire. CD4 cell slopes were estimated using a mixed linear model. Probabilities of crossing the 350 and 500 cells/µl CD4 cell thresholds were estimated by the Kaplan-Meier method. RESULTS: Between 1997 and 2009, 304 recent seroconverters have been enrolled in the Primo-CI cohort (62% men, median baseline age 29 years and median time since the estimated date of seroconversion 9 months). The probability of having a first CD4 cell count below 500 cells/µl was 0.57, 0.72, 0.79 and 0.84 at study entry, 2, 4 and 6 years, respectively. For a first CD4 cell count below 350 cells/µl, these figures were 0.29, 0.40, 0.55 and 0.67. The time for 75% of patients to reach the threshold was 3.0 years for 500 cells/µl and 7.0 years for 350 cells/µl.


Asunto(s)
Antirretrovirales/administración & dosificación , Recuento de Linfocito CD4 , Infecciones por VIH/tratamiento farmacológico , Seropositividad para VIH/tratamiento farmacológico , VIH-1 , Adulto , Quimioterapia Combinada , Seropositividad para VIH/diagnóstico , Humanos , Masculino
9.
J Acquir Immune Defic Syndr ; 56(4): 356-64, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21191309

RESUMEN

BACKGROUND: Adherence is a strong determinant of viral suppression with antiretroviral therapy (ART) but measuring it is challenging. Medication delivery can be measured accurately in settings with computerized prescription databases. We studied the association between medication possession ratio (MPR), virologic suppression, and resistance to ART in Côte d'Ivoire. METHODS: We conducted a prospective cohort study of HIV-1-infected adults initiating ART in 3 clinics using computerized monitoring systems. Patients had viral load (VL) tests at month 6 (M6) and month 12 (M12) after ART initiation and genotype tests if VL was detectable (≥300 copies/mL). MPR was defined as the number of daily doses of antiretroviral drug actually provided divided by the total number of follow-up days since ART initiation. RESULTS: Overall, 1573 patients started ART with stavudine/zidovudine plus lamivudine plus nevirapine/efavirenz. At M6 and M12, 996 and 942 patients were in active follow-up; 20% (M6) and 25% (M12) of patients had detectable VL, including 7% (M6) and 11% (M12) with ≥1 resistance mutation. Among patients with MPR of ≥95%, 80%-94%, 65%-79%, 50%-64%, and <50% at M12, the proportion with detectable VL [resistance] was 9% [4%], 17% [7%], 45% [24%], 67% [31%], and 85% [37%]. Among patients with ≥1 mutation at M12, 86% were resistant to lamivudine/emtricitabine and/or nevirapine/efavirenz but not to other drugs. CONCLUSIONS: MPR was strongly associated with virologic outcomes. Half of those with detectable VL at M12 had no resistance mutations. MPR should be used at M6 to identify patients who might benefit from early interventions to reinforce adherence.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa/métodos , Farmacorresistencia Viral , Utilización de Medicamentos/estadística & datos numéricos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Adulto , Estudios de Cohortes , Côte d'Ivoire , Recolección de Datos/métodos , Femenino , Humanos , Masculino , Cumplimiento de la Medicación/estadística & datos numéricos , Estudios Prospectivos , Carga Viral
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