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1.
Elife ; 122023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37988285

RESUMEN

Reverse genetic systems enable the engineering of RNA virus genomes and are instrumental in studying RNA virus biology. With the recent outbreak of the coronavirus disease 2019 pandemic, already established methods were challenged by the large genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Herein we present an elaborated strategy for the rapid and straightforward rescue of recombinant plus-stranded RNA viruses with high sequence fidelity using the example of SARS-CoV-2. The strategy called CLEVER (CLoning-free and Exchangeable system for Virus Engineering and Rescue) is based on the intracellular recombination of transfected overlapping DNA fragments allowing the direct mutagenesis within the initial PCR-amplification step. Furthermore, by introducing a linker fragment - harboring all heterologous sequences - viral RNA can directly serve as a template for manipulating and rescuing recombinant mutant virus, without any cloning step. Overall, this strategy will facilitate recombinant SARS-CoV-2 rescue and accelerate its manipulation. Using our protocol, newly emerging variants can quickly be engineered to further elucidate their biology. To demonstrate its potential as a reverse genetics platform for plus-stranded RNA viruses, the protocol has been successfully applied for the cloning-free rescue of recombinant Chikungunya and Dengue virus.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/genética , Genética Inversa/métodos , ARN Viral/genética , Mutagénesis
2.
Viruses ; 15(8)2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-37632035

RESUMEN

Numerous mammalian viruses are routinely analyzed in clinical diagnostic laboratories around the globe or serve as indispensable model systems in viral research. Potentially infectious viral entities are handled as blood, biopsies, or cell and tissue culture samples. Countless protocols describe methods for virus fixation and inactivation, yet for many, a formal proof of safety and completeness of inactivation remains to be shown. While modern nucleic acid extraction methods work quite effectively, data are largely lacking on possible residual viral infectivity, e.g., when assessed after extended culture times, which maximizes the sensitivity for low levels of residual infectiousness. Therefore, we examined the potency and completeness of inactivation procedures on virus-containing specimens when applying commonly used fixatives like formaldehyde or nucleic acid extraction/lysis buffers. Typical representatives of different virus classes, including RNA and DNA viruses, enveloped and non-enveloped, such as adenovirus, enterovirus, lentivirus, and coronavirus, were used, and the reduction in the in vitro infectiousness was assessed for standard protocols. Overall, a 30-minute incubation with formaldehyde at room temperature effectively inactivated all tested enveloped and non-enveloped viruses. Full inactivation of HIV-1 and ECHO-11 was also achieved with all buffers in the test, whereas for SARS-CoV-2 and AdV-5, only five of the seven lysis buffers were fully effective under the tested conditions.


Asunto(s)
COVID-19 , Inactivación de Virus , Animales , SARS-CoV-2 , Formaldehído/farmacología , Adenoviridae , Mamíferos
3.
Cell Rep Methods ; 3(6): 100485, 2023 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-37426753

RESUMEN

While combination therapy completely suppresses HIV-1 replication in blood, functional virus persists in CD4+ T cell subsets in non-peripheral compartments that are not easily accessible. To fill this gap, we investigated tissue-homing properties of cells that transiently appear in the circulating blood. Through cell separation and in vitro stimulation, the HIV-1 "Gag and Envelope reactivation co-detection assay" (GERDA) enables sensitive detection of Gag+/Env+ protein-expressing cells down to about one cell per million using flow cytometry. By associating GERDA with proviral DNA and polyA-RNA transcripts, we corroborate the presence and functionality of HIV-1 in critical body compartments utilizing t-distributed stochastic neighbor embedding (tSNE) and density-based spatial clustering of applications with noise (DBSCAN) clustering with low viral activity in circulating cells early after diagnosis. We demonstrate transcriptional HIV-1 reactivation at any time, potentially giving rise to intact, infectious particles. With single-cell level resolution, GERDA attributes virus production to lymph-node-homing cells with central memory T cells (TCMs) as main players, critical for HIV-1 reservoir eradication.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Humanos , VIH-1/genética , Linfocitos T CD4-Positivos , Subgrupos de Linfocitos T
4.
bioRxiv ; 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37292682

RESUMEN

Reverse genetic systems enable the engineering of RNA virus genomes and are instrumental in studying RNA virus biology. With the recent outbreak of the COVID-19 pandemic, already established methods were challenged by the large genome of SARS-CoV-2. Herein we present an elaborated strategy for the rapid and straightforward rescue of recombinant plus-stranded RNA viruses with high sequence fidelity, using the example of SARS-CoV-2. The strategy called CLEVER (CLoning-free and Exchangeable system for Virus Engineering and Rescue) is based on the intracellular recombination of transfected overlapping DNA fragments allowing the direct mutagenesis within the initial PCR-amplification step. Furthermore, by introducing a linker fragment - harboring all heterologous sequences - viral RNA can directly serve as a template for manipulating and rescuing recombinant mutant virus, without any cloning step. Overall, this strategy will facilitate recombinant SARS-CoV-2 rescue and accelerate its manipulation. Using our protocol, newly emerging variants can quickly be engineered to further elucidate their biology. To demonstrate its potential as a reverse genetics platform for plus-stranded RNA viruses, the protocol has been successfully applied for the cloning-free rescue of recombinant Chikungunya and Dengue virus.

5.
BMC Infect Dis ; 23(1): 222, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37029356

RESUMEN

INTRODUCTION: Monitoring HIV viral load (HVL) in people living with HIV (PLHIV) on antiretroviral therapy (ART) is recommended by the World Health Organization. Implementation of HVL testing programs have been affected by logistic and organizational challenges. Here we describe the HVL monitoring cascade in a rural setting in Tanzania and compare turnaround times (TAT) between an on-site and a referral laboratory. METHODS: In a nested study of the prospective Kilombero and Ulanga Antiretroviral Cohort (KIULARCO) we included PLHIV aged ≥ 15 years, on ART for ≥ 6 months after implementation of routine HVL monitoring in 2017. We assessed proportions of PLHIV with a blood sample taken for HVL, whose results came back, and who were virally suppressed (HVL < 1000 copies/mL) or unsuppressed (HVL ≥ 1000 copies/mL). We described the proportion of PLHIV with unsuppressed HVL and adequate measures taken as per national guidelines and outcomes among those with low-level viremia (LLV; 100-999 copies/mL). We compare TAT between on-site and referral laboratories by Wilcoxon rank sum tests. RESULTS: From 2017 to 2020, among 4,454 PLHIV, 4,238 (95%) had a blood sample taken and 4,177 (99%) of those had a result. Of those, 3,683 (88%) were virally suppressed. In the 494 (12%) unsuppressed PLHIV, 425 (86%) had a follow-up HVL (102 (24%) within 4 months and 158 (37%) had virologic failure. Of these, 103 (65%) were already on second-line ART and 32/55 (58%) switched from first- to second-line ART after a median of 7.7 months (IQR 4.7-12.7). In the 371 (9%) PLHIV with LLV, 327 (88%) had a follow-up HVL. Of these, 267 (82%) resuppressed to < 100 copies/ml, 41 (13%) had persistent LLV and 19 (6%) had unsuppressed HVL. The median TAT for return of HVL results was 21 days (IQR 13-39) at the on-site versus 59 days (IQR 27-99) at the referral laboratory (p < 0.001) with PLHIV receiving the HVL results after a median of 91 days (IQR 36-94; similar for both laboratories). CONCLUSION: Robust HVL monitoring is achievable in remote resource-limited settings. More focus is needed on care models for PLHIV with high viral loads to timely address results from routine HVL monitoring.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Humanos , Estudios Prospectivos , Carga Viral/métodos , Tanzanía/epidemiología , Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Política , Fármacos Anti-VIH/uso terapéutico
6.
HIV Med ; 24(2): 153-162, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35730213

RESUMEN

INTRODUCTION: HIV programmes across many countries in Africa have recently transitioned people living with HIV from efavirenz (EFV)- to dolutegravir (DTG)-containing antiretroviral therapy (ART). As both drugs are associated with neuropsychiatric adverse effects, this study assessed the mental health and HIV/ART-associated symptoms of people living with HIV before and after transition to DTG. METHODS: The prospective DO-REAL cohort enrolled people starting DTG-based ART in Lesotho from February to December 2020. For this analysis within DO-REAL, we included adults changing from tenofovir disoproxil fumarate (TDF)/lamivudine (3TC)/EFV to TDF/3TC/DTG within first-line therapy. At transition and 16 weeks thereafter, participants completed the Patient Health Questionnaire-9 (PHQ-9; depression screening), the 12-item Short-Form Health Survey (SF-12; mental and physical health), and a modified HIV Symptom Index (mHSI; HIV/ART-related symptoms). We also assessed weight change. We used McNemar tests with Bonferroni corrections to assess binary outcomes. CLINICALTRIALS: gov: NCT04238767. RESULTS: Among 1228 participants, 1131 completed follow-up. Of these, 60.0% were female, the median age was 46 years (interquartile range [IQR] 38-55), and the median time taking ART was 5.7 years (IQR 3.5-8.9). No change was observed for weight or overall PHQ-9 or SF-12 outcomes. However, three mHSI items decreased at follow-up: 'feeling sad/down/depressed' (bothered 6.0% vs. 3.3% of participants at least 'a little' before vs. after transition; adjusted p = 0.048); 'feeling nervous/anxious' (7.4% vs. 3.4%; adjusted p = 0.0009); and 'nightmares, strange/vivid dreams' (6.3% vs. 3.5%; adjusted p = 0.027). Individual PHQ-9 or SF-12 items also improved. Being symptom free across all measures increased from 5.1% to 11.4% (p < 0.0001). CONCLUSIONS: We observed no negative impacts and potential moderate improvements with DTG, providing further support for the rollout of DTG.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Adulto , Humanos , Femenino , Persona de Mediana Edad , Masculino , Infecciones por VIH/tratamiento farmacológico , Fármacos Anti-VIH/efectos adversos , Estudios Prospectivos , Lesotho , Autoinforme , Oxazinas/uso terapéutico , Benzoxazinas/efectos adversos , Lamivudine/uso terapéutico , Compuestos Heterocíclicos con 3 Anillos/efectos adversos , Tenofovir/efectos adversos , Evaluación de Resultado en la Atención de Salud
7.
Viruses ; 14(12)2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-36560685

RESUMEN

Experimental work with viruses that are highly pathogenic for humans and animals requires specialized Biosafety Level 3 or 4 facilities. Such pathogens include some spectacular but also rather seldomly studied examples such as Ebola virus (requiring BSL-4), more wide-spread and commonly studied viruses such as HIV, and the most recent example, SARS-CoV-2, which causes COVID-19. A common characteristic of these virus examples is that their genomes consist of single-stranded RNA, which requires the conversion of their genomes into a DNA copy for easy manipulation; this can be performed to study the viral life cycle in detail, develop novel therapies and vaccines, and monitor the disease course over time for chronic virus infections. We summarize the recent advances in such new genetic applications for RNA viruses in Switzerland over the last 25 years, from the early days of the HIV/AIDS epidemic to the most recent developments in research on the SARS-CoV-2 coronavirus. We highlight game-changing collaborative efforts between clinical and molecular disciplines in HIV research on the path to optimal clinical disease management. Moreover, we summarize how the modern technical evolution enabled the molecular studies of emerging RNA viruses, confirming that Switzerland is at the forefront of SARS-CoV-2 research and potentially other newly emerging viruses.


Asunto(s)
COVID-19 , Infecciones por VIH , Virus ARN , Animales , Humanos , SARS-CoV-2/genética , Virus ARN/genética , Biología Molecular
8.
Open Forum Infect Dis ; 9(12): ofac611, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36540386

RESUMEN

Background: Information about burden, characteristics, predictors, and outcomes of advanced human immunodeficiency virus disease (AHD) is scarce in rural settings of sub-Saharan Africa. Human immunodeficiency virus (HIV) infections and associated deaths remain high despite specific guidelines issued by the World Health Organization (WHO). Methods: Burden of AHD and 6-month death/loss to follow-up (LTFU) were described among 2498 antiretroviral therapy (ART)-naive nonpregnant people with HIV (PWH) aged >15 years enrolled in the Kilombero Ulanga Antiretroviral Cohort in rural Tanzania between 2013 and 2019. Baseline characteristics associated with AHD and predictors of death/LTFU among those with AHD were analyzed using multivariate logistic and Cox regression, respectively. Results: Of the PWH, 62.2% had AHD at diagnosis (66.8% before vs 55.7% after national uptake of WHO "test and treat" guidelines in 2016). At baseline, older age, male sex, lower body mass index, elevated aminotransferase aspartate levels, severe anemia, tachycardia, decreased glomerular filtration rate, clinical complaints, impaired functional status, and enrollment into care before 2018 were independently associated with AHD. Among people with AHD, incidence of mortality, and LTFU were 16 and 34 per 100 person-years, respectively. WHO clinical stage 3 or 4, CD4 counts <100 cells/µL, severe anemia, tachypnea, and liver disease were associated with death/LTFU. Conclusions: More than 50% of PWH enrolled in our cohort after test and treat implementation still had AHD at diagnosis. Increasing HIV testing and uptake and implementation of the WHO-specific guidelines on AHD for prevention, diagnosis, treatment of opportunistic infections, and reducing the risks of LTFU are urgently needed to reduce morbidity and mortality.

9.
Mol Biol Evol ; 39(8)2022 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-35921544

RESUMEN

Infectious diseases are particularly challenging for genome-wide association studies (GWAS) because genetic effects from two organisms (pathogen and host) can influence a trait. Traditional GWAS assume individual samples are independent observations. However, pathogen effects on a trait can be heritable from donor to recipient in transmission chains. Thus, residuals in GWAS association tests for host genetic effects may not be independent due to shared pathogen ancestry. We propose a new method to estimate and remove heritable pathogen effects on a trait based on the pathogen phylogeny prior to host GWAS, thus restoring independence of samples. In simulations, we show this additional step can increase GWAS power to detect truly associated host variants when pathogen effects are highly heritable, with strong phylogenetic correlations. We applied our framework to data from two different host-pathogen systems, HIV in humans and X. arboricola in A. thaliana. In both systems, the heritability and thus phylogenetic correlations turn out to be low enough such that qualitative results of GWAS do not change when accounting for the pathogen shared ancestry through a correction step. This means that previous GWAS results applied to these two systems should not be biased due to shared pathogen ancestry. In summary, our framework provides additional information on the evolutionary dynamics of traits in pathogen populations and may improve GWAS if pathogen effects are highly phylogenetically correlated amongst individuals in a cohort.


Asunto(s)
Enfermedades Transmisibles , Estudio de Asociación del Genoma Completo , Enfermedades Transmisibles/genética , Estudio de Asociación del Genoma Completo/métodos , Humanos , Fenotipo , Filogenia , Polimorfismo de Nucleótido Simple , Carácter Cuantitativo Heredable
10.
Front Pharmacol ; 13: 904231, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35935828

RESUMEN

Several species of the Helichrysum genus have been used ethnobotanically to treat conditions that we today know have been caused by viral infections. Since HIV is a modern disease with no ethnobotanical history, we commenced with a study on the anti-HIV activity of several Helichrysum species. Drug discovery of small molecules from natural resources that is based on the integration of chemical and biological activity by means of metabolomical analyses, enables faster and a more cost-effective path to identify active compounds without the need for a long process of bioassay-guided fractionation. This study used metabolomics to identify anti-HIV compounds as biomarkers from 57 Helichrysum species in a combined study of the chemical and biological data of two previous studies. In the OPLS-DA and hierarchical cluster analyses, anti-HIV activity data was included as a secondary observation, which assisted in the correlation of the phytochemical composition and biological activity of the samples. Clear grouping revealed similarity in chemical composition and bioactivity of the samples. Based on the biological activity of polar extracts, there was a distinct phytochemical difference between active and non-active groups of extracts. This NMR-based metabolomic investigation showed that the chlorogenic acids, compounds with cinnamoyl functional groups, and quinic acid were the most prominent compounds in the Helichrysum species with anti-HIV activity. This study further revealed that the chlorogenic acid type compounds and quinic acid are biomarkers for anti-HIV activity.

11.
Viruses ; 14(7)2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35891417

RESUMEN

Despite the success of combination antiretroviral therapy (cART), HIV persists in low- and middle-income countries (LMIC) due to emerging drug resistance and insufficient drug accessibility. Furthermore, cART does not target latently-infected CD4+ T cells, which represent a major barrier to HIV eradication. The "shock and kill" therapeutic approach aims to reactivate provirus expression in latently-infected cells in the presence of cART and target virus-expressing cells for elimination. An attractive therapeutic prototype in LMICs would therefore be capable of simultaneously inhibiting viral replication and inducing latency reversal. Here we report that Gnidia sericocephala, which is used by traditional health practitioners in South Africa for HIV/AIDS management to supplement cART, contains at least four daphnane-type compounds (yuanhuacine A (1), yuanhuacine as part of a mixture (2), yuanhuajine (3), and gniditrin (4)) that inhibit viral replication and/or reverse HIV latency. For example, 1 and 2 inhibit HIV replication in peripheral blood mononuclear cells (PBMC) by >80% at 0.08 µg/mL, while 1 further inhibits a subtype C virus in PBMC with a half-maximal effective concentration (EC50) of 0.03 µM without cytotoxicity. Both 1 and 2 also reverse HIV latency in vitro consistent with protein kinase C activation but at 16.7-fold lower concentrations than the control prostratin. Both 1 and 2 also reverse latency in primary CD4+ T cells from cART-suppressed donors with HIV similar to prostratin but at 6.7-fold lower concentrations. These results highlight G. sericocephala and components 1 and 2 as anti-HIV agents for improving cART efficacy and supporting HIV cure efforts in resource-limited regions.


Asunto(s)
Diterpenos , Infecciones por VIH , VIH-1 , Plantas Medicinales , Thymelaeaceae , Linfocitos T CD4-Positivos , Cromatografía Líquida de Alta Presión , Diterpenos/farmacología , Diterpenos/uso terapéutico , VIH-1/fisiología , Humanos , Leucocitos Mononucleares/metabolismo , Activación Viral , Latencia del Virus
12.
J Infect Dis ; 226(7): 1256-1266, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-35485458

RESUMEN

BACKGROUND: Studying human immunodeficiency virus type 1 (HIV-1) superinfection is important to understand virus transmission, disease progression, and vaccine design. But detection remains challenging, with low sampling frequencies and insufficient longitudinal samples. METHODS: Using the Swiss HIV Cohort Study (SHCS), we developed a molecular epidemiology screening for superinfections. A phylogeny built from 22 243 HIV-1 partial polymerase sequences was used to identify potential superinfections among 4575 SHCS participants with longitudinal sequences. A subset of potential superinfections was tested by near-full-length viral genome sequencing (NFVGS) of biobanked plasma samples. RESULTS: Based on phylogenetic and distance criteria, 325 potential HIV-1 superinfections were identified and categorized by their likelihood of being detected as superinfections due to sample misidentification. NFVGS was performed for 128 potential superinfections; of these, 52 were confirmed by NFVGS, 15 were not confirmed, and for 61 sampling did not allow confirming or rejecting superinfection because the sequenced samples did not include the relevant time points causing the superinfection signal in the original screen. Thus, NFVGS could support 52 of 67 adequately sampled potential superinfections. CONCLUSIONS: This cohort-based molecular approach identified, to our knowledge, the largest population of confirmed superinfections, showing that, while rare with a prevalence of 1%-7%, superinfections are not negligible events.


Asunto(s)
Infecciones por VIH , VIH-1 , Sobreinfección , Vacunas , Estudios de Cohortes , Humanos , Epidemiología Molecular , Filogenia , Sobreinfección/epidemiología , Suiza/epidemiología
13.
J Acquir Immune Defic Syndr ; 90(4): e4-e12, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35298446

RESUMEN

OBJECTIVES: Phylogenetic analyses of 2 or more countries allow to detect differences in transmission dynamics of local HIV-1 epidemics beyond differences in demographic characteristics. METHODS: A maximum-likelihood phylogenetic tree was built using pol -sequences of the Swiss HIV Cohort Study (SHCS) and the Austrian HIV Cohort Study (AHIVCOS), with international background sequences. Three types of phylogenetic cherries (clusters of size 2) were analyzed further: (1) domestic cherries; (2) international cherries; and (3) SHCS/AHIVCOS-cherries. Transmission group and ethnicities observed within the cherries were compared with the respective distribution expected from a random distribution of patients on the phylogeny. RESULTS: The demographic characteristics of the AHIVCOS (included patients: 3'141) and the SHCS (included patients: 12'902) are very similar. In the AHIVCOS, 36.5% of the patients were in domestic cherries, 8.3% in international cherries, and 7.0% in SHCS/AHIVCOS cherries. Similarly, in the SHCS, 43.0% of the patients were in domestic cherries, 8.2% in international cherries, and 1.7% in SHCS/AHIVCOS cherries. Although international cherries in the SHCS were dominated by heterosexuals with men who have sex with men being underrepresented, the opposite was the case for the AHIVCOS. In both cohorts, cherries with one patient belonging to the transmission group intravenous drug user and the other one non-intravenous drug user were underrepresented. CONCLUSIONS: In both cohorts, international HIV transmission plays a major role in the local epidemics, mostly driven by men who have sex with men in the AHIVOS, and by heterosexuals in the SHCS, highlighting the importance of international collaborations to understand global HIV transmission links on the way to eliminate HIV.


Asunto(s)
Epidemias , Infecciones por VIH , Seropositividad para VIH , VIH-1 , Minorías Sexuales y de Género , Abuso de Sustancias por Vía Intravenosa , Austria/epidemiología , Análisis por Conglomerados , Estudios de Cohortes , Infecciones por VIH/tratamiento farmacológico , Seropositividad para VIH/epidemiología , VIH-1/genética , Homosexualidad Masculina , Humanos , Masculino , Filogenia , Abuso de Sustancias por Vía Intravenosa/epidemiología , Suiza/epidemiología
14.
Viruses ; 14(2)2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-35215999

RESUMEN

Little is known about whether and how variation in the HIV-1 genome affects its transmissibility. Assessing which genomic features of HIV-1 are under positive or negative selection during transmission is challenging, because very few virus particles are typically transmitted, and random genetic drift can dilute genetic signals in the recipient virus population. We analyzed 30 transmitter-recipient pairs from the Zurich Primary HIV Infection Study and the Swiss HIV Cohort Study using near full-length HIV-1 genomes. We developed a new statistical test to detect selection during transmission, called Selection Test in Transmission (SeTesT), based on comparing the transmitter and recipient virus population and accounting for the transmission bottleneck. We performed extensive simulations and found that sensitivity of detecting selection during transmission is limited by the strong population bottleneck of few transmitted virions. When pooling individual test results across patients, we found two candidate HIV-1 genomic features for affecting transmission, namely amino acid positions 3 and 18 of Vpu, which were significant before but not after correction for multiple testing. In summary, SeTesT provides a general framework for detecting selection based on genomic sequencing data of transmitted viruses. Our study shows that a higher number of transmitter-recipient pairs is required to improve sensitivity of detecting selection.


Asunto(s)
Infecciones por VIH/transmisión , VIH-1/genética , Heterosexualidad , Selección Genética , Transmisión de Enfermedad Infecciosa/estadística & datos numéricos , Femenino , Variación Genética , Proteínas del Virus de la Inmunodeficiencia Humana/genética , Humanos , Masculino , Modelos Estadísticos , Datos de Secuencia Molecular , Mutación Puntual
15.
Viruses ; 14(1)2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-35062310

RESUMEN

The coronavirus disease 2019 (COVID-19), caused by a novel coronavirus (SARS-CoV-2), has spread worldwide, affecting over 250 million people and resulting in over five million deaths. Antivirals that are effective are still limited. The antiviral activities of the Petasites hybdridus CO2 extract Ze 339 were previously reported. Thus, to assess the anti-SARS-CoV-2 activity of Ze 339 as well as isopetasin and neopetasin as major active compounds, a CPE and plaque reduction assay in Vero E6 cells was used for viral output. Antiviral effects were tested using the original virus (Wuhan) and the Delta variant of SARS-CoV-2. The antiviral drug remdesivir was used as control. Pre-treatment with Ze 339 in SARS-CoV-2-infected Vero E6 cells with either virus variant significantly inhibited virus replication with IC50 values of 0.10 and 0.40 µg/mL, respectively. The IC50 values obtained for isopetasin ranged between 0.37 and 0.88 µM for both virus variants, and that of remdesivir ranged between 1.53 and 2.37 µM. In conclusion, Ze 339 as well as the petasins potently inhibited SARS-CoV-2 replication in vitro of the Wuhan and Delta variants. Since time is of essence in finding effective treatments, clinical studies will have to demonstrate if Ze339 can become a therapeutic option to treat SARS-CoV-2 infections.


Asunto(s)
Antivirales/farmacología , Extractos Vegetales/farmacología , SARS-CoV-2/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/farmacología , Alanina/análogos & derivados , Alanina/farmacología , Animales , Antivirales/química , Dióxido de Carbono/química , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Relación Dosis-Respuesta a Droga , Variación Genética , Petasites/química , Extractos Vegetales/química , SARS-CoV-2/genética , Sesquiterpenos/química , Sesquiterpenos/farmacología , Células Vero
16.
HIV Med ; 23(3): 287-293, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34632682

RESUMEN

OBJECTIVES: Since 2018, the World Health Organization has recommended dolutegravir (DTG)-containing antiretroviral therapy (ART) for most people living with HIV. Country programmes across Africa have subsequently transitioned from other, mostly nonnucleoside reverse transcriptase inhibitor (NNRTI)-based ART to DTG-based ART. This study aims to assess the virological impact of programmatic transitioning to DTG-based ART in Lesotho. METHODS: The prospective Dolutegravir in Real-Life in Lesotho (DO-REAL) cohort enrols people living with HIV initiating or transitioning to DTG-based ART in Lesotho. Here, we present data from participants who transitioned from NNRTI- to DTG-based ART between February and December 2020. Blood samples collected at transition and at 16 weeks' follow-up (window 8-32 weeks) were used for viral load (VL) and resistance testing. RESULTS: Among 1347 participants, follow-up data was available for 1225. The majority (60%) were female, median age at transition was 47 years [interquartile range (IQR): 38-56], and median (IQR) time since ART initiation was 5.9 (3.5-9.0) years. Among those with complete VL data, the rate of viral suppression to < 100 copies/mL was 1093/1116 (98%) before, 1073/1116 (96%) at, and 1098/1116 (98%) after transition. Even among those with a VL ≥ 100 copies/mL at transition, 42/44 (95%) achieved suppression to < 100 copies/mL at follow-up. Seven participants had a VL ≥ 1000 copies/mL at follow-up and did not harbour any integrase mutations associated with resistance to DTG. CONCLUSIONS: The high levels of viral suppression observed are encouraging regarding virological outcomes upon programmatic transitioning from NNRTI- to DTG-based ART.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Fármacos Anti-VIH/uso terapéutico , Estudios de Cohortes , Femenino , Infecciones por VIH/tratamiento farmacológico , Compuestos Heterocíclicos con 3 Anillos , Humanos , Lesotho , Masculino , Persona de Mediana Edad , Oxazinas , Piperazinas , Estudios Prospectivos , Piridonas , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Carga Viral
17.
Pediatr Infect Dis J ; 41(3): e75-e80, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34862344

RESUMEN

BACKGROUND: Children living with HIV and taking antiretroviral therapy (ART) are a priority group for routine viral load (VL) monitoring. As per Lesotho guidelines, a VL ≥1000 copies/mL ("unsuppressed") should trigger adherence counseling and a follow-up VL; 2 consecutive unsuppressed VLs ("virologic failure") qualify for switching to second-line ART, with some exceptions. Here, we describe the pediatric VL cascade in Lesotho. METHODS: In a prospective open cohort study comprising routine VL results from 22 clinics in Lesotho, we assessed outcomes along the VL cascade for children who had at least 1 VL test from January 2016 through June 2020. Data were censored on February 10, 2021. RESULTS: In total, 1215 children received 5443 VL tests. The median age was 10 years (interquartile range 7-13) and 627/1215 (52%) were female; 362/1215 (30%) had at least 1 unsuppressed VL. A follow-up VL was available for 325/362 (90%), although only for 159/362 (44%) within 6 months of the first unsuppressed VL. Of those with a follow-up VL, 172/329 (53%) had virologic failure and 123/329 (37%) qualified for switching to second-line ART. Of these, 55/123 (45%) were ever switched, although only 9/123 (7%) were switched within 12 weeks of the follow-up VL. Delays were more pronounced in rural facilities. Overall, 100/362 (28%) children with an unsuppressed VL received a timely follow-up VL and, if required, a timely regimen switch. CONCLUSIONS: Despite access to VL monitoring, clinical management was suboptimal. HIV programs should prioritize timely clinical action to maximize the benefits of VL monitoring.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Carga Viral/efectos de los fármacos , Adolescente , África Austral , Fármacos Anti-VIH/normas , Antirretrovirales/normas , Antirretrovirales/uso terapéutico , Niño , Estudios de Cohortes , Femenino , Humanos , Lesotho , Masculino , Estudios Prospectivos , Población Rural , Insuficiencia del Tratamiento , Resultado del Tratamiento
18.
PLoS Med ; 18(10): e1003839, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34673765

RESUMEN

BACKGROUND: Community-based antiretroviral therapy (ART) dispensing by lay workers is an important differentiated service delivery model in sub-Sahara Africa. However, patients new in care are generally excluded from such models. Home-based same-day ART initiation is becoming widespread practice, but linkage to the clinic is challenging. The pragmatic VIBRA (Village-Based Refill of ART) trial compared ART refill by existing lay village health workers (VHWs) versus clinic-based refill after home-based same-day ART initiation. METHODS AND FINDINGS: The VIBRA trial is a cluster-randomized open-label clinical superiority trial conducted in 249 rural villages in the catchment areas of 20 health facilities in 2 districts (Butha-Buthe and Mokhotlong) in Lesotho. In villages (clusters) randomized to the intervention arm, individuals found to be HIV-positive during a door-to-door HIV testing campaign were offered same-day ART initiation with the option of refill by VHWs. The trained VHWs dispensed drugs and scheduled clinic visits for viral load measurement at 6 and 12 months. In villages randomized to the control arm, participants were offered same-day ART initiation with clinic-based ART refill. The primary outcome was 12-month viral suppression. Secondary endpoints included linkage and 12-month engagement in care. Analyses were intention-to-treat. The trial was registered on ClinicalTrials.gov (NCT03630549). From 16 August 2018 until 28 May 2019, 118 individuals from 108 households in 57 clusters in the intervention arm, and 139 individuals from 130 households in 60 clusters in the control arm, were enrolled (150 [58%] female; median age 36 years [interquartile range 30-48]; 200 [78%] newly diagnosed). In the intervention arm, 48/118 (41%) opted for VHW refill. At 12 months, 46/118 (39%) participants in the intervention arm and 64/139 (46%) in the control arm achieved viral suppression (adjusted risk difference -0.07 [95% CI -0.20 to 0.06]; p = 0.256). Arms were similar in linkage (adjusted risk difference 0.03 [-0.10 to 0.16]; p = 0.630), but engagement in care was non-significantly lower in the intervention arm (adjusted risk difference -0.12 [-0.23 to 0.003]; p = 0.058). Seven and 0 deaths occurred in the intervention and control arm, respectively. Of the intervention participants who did not opt for drug refill from the VHW at enrollment, 41/70 (59%) mentioned trust or conflict issues as the primary reason. Study limitations include a rather small sample size, 9% missing viral load measurements in the primary endpoint window, the low uptake of the VHW refill option in the intervention arm, and substantial migration among the study population. CONCLUSIONS: The offer of village-based ART refill after same-day initiation led to similar outcomes as clinic-based refill. The intervention did not amplify the effect of home-based same-day ART initiation alone. The findings raise concerns about acceptance and safety of ART delivered by lay health workers after initiation in the community. TRIAL REGISTRATION: Registered with Clinicaltrials.gov (NCT03630549).


Asunto(s)
Terapia Antirretroviral Altamente Activa , Agentes Comunitarios de Salud , Adulto , Análisis por Conglomerados , Determinación de Punto Final , Femenino , Estudios de Seguimiento , Humanos , Lesotho , Masculino , Persona de Mediana Edad
19.
Open Forum Infect Dis ; 8(5): ofab046, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34046513

RESUMEN

BACKGROUND: In resource-limited settings, the World Health Organization recommends enhanced adherence counseling (EAC) for individuals with an unsuppressed human immunodeficiency virus (HIV)-1 viral load (VL) and to remeasure VL after 3 months to avoid unnecessary regimen switches. In cases in which this follow-up VL remains unsuppressed, a regimen switch is indicated. We aimed to assess levels of HIV-1 drug resistance before and after the EAC period among people with ongoing viremia (≥80 c/mL) after EAC. METHODS: We included adult participants of the CART-1 cohort study conducted in Lesotho who had a VL ≥80 c/mL after EAC. Paired plasma samples (before and after EAC) were analyzed by next-generation sequencing. We assessed the prevalence of resistance-associated mutations and viral susceptibility scores to each participant's antiretroviral therapy (ART) regimen (range, 0-3; 3 indicates complete susceptibility). RESULTS: Among 93 participants taking nonnucleoside reverse-transcriptase inhibitor-based ART with an initial VL ≥1000 copies/mL who received a follow-up VL test after EAC, 76 still had a VL ≥80 copies/mL after EAC, and paired samples were available for 57 of 76. The number of individuals without full susceptibility to any drug in their regimen increased from 31 of 57 (54.4%) before to 36 of 57 (63.2%) after EAC. Median susceptibility scores dropped from 0.5 (interquartile range [IQR] = 0.25-) to 0.25 (IQR = 0.25-1) during the EAC period (P = .16). CONCLUSIONS: Despite high levels of resistance before EAC, we observed a slight decline in susceptibility scores after EAC. The risk of further accumulation of resistance during EAC has to be balanced against the benefit of avoiding unnecessary switches in those with spontaneous resuppression after EAC.

20.
J Clin Virol ; 136: 104755, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33639408

RESUMEN

OBJECTIVES: Geno2pheno[coreceptor] is a widely used tool for the prediction of coreceptor usage (viral tropism) of HIV-1 samples. For HIV-1 CRF01_AE, a significant overcalling of X4-tropism is observed when using the standard settings of Geno2pheno[coreceptor]. The aim of this study was to provide the experimental backing for adaptations to the geno2pheno[coreceptor] algorithm in order to improve coreceptor usage predictions of clinical HIV-1 CRF01_AE isolates STUDY DESIGN: V3-sequences of 20 clinical HIV-1 subtype CRF01_AE samples were sequenced and analyzed by geno2pheno[coreceptor]. In parallel, coreceptor usage was determined for these samples by replicative phenotyping in human cells in the presence of specific X4- or R5-inhibitors. RESULTS: The sole introduction of the CRF01_AE V3 region into a full-length otherwise subtype B provirus failed to produce replication-competent viral progeny. A successive genome-replacement strategy revealed that also CRF01_AE derived gag and pol sequences are necessary to generate HIV genomes with sufficient replication competence. Subsequent phenotypic analysis confirmed overcalling of X4-tropism for CRF01_AE viruses using the current version and the standard cut-off at 10% false positive rate (FPR) of geno2pheno[coreceptor]. Lowering the FPR cut-off to 2.5% reduced the X4-overcalling in our sample collection, while still allowing a safe administration of Maraviroc (MCV). CONCLUSION: This study demonstrates the successful adjustment of geno2pheno[coreceptor] rules for subtype CRF01_AE. It also supports the unique strength of combining complementing methods, namely phenotyping and genotyping, for validating new bioinformatics tools prior to application in diagnostics.


Asunto(s)
Infecciones por VIH , VIH-1 , Asia Oriental , Genotipo , VIH-1/genética , Humanos , Tropismo Viral
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