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1.
Lancet Reg Health Am ; 33: 100751, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38711788

RESUMEN

Background: We examined HIV prevalence and transmission dynamics among people who inject drugs in the U.S./Mexico border region during the COVID-19 pandemic. Methods: People who inject drugs aged ≥18 years from 3 groups were recruited: people who inject drugs who live in San Diego (SD) and engaged in cross-border drug use in Tijuana, Mexico (SD CBDUs), and people who inject drugs in SD and Tijuana (TJ) who did not engage in cross-border drug use (NCBDUs). We computed HIV prevalence at baseline and bivariate incidence-density rates (IR) at 18-month follow-up. Bayesian phylogenetic analysis was used to identify local transmission clusters, estimate their age, and effective reproductive number (Re) over time within the clusters. Findings: At baseline (n = 612), 26% of participants were female, 9% engaged in sex work, and HIV prevalence was 8% (4% SD CBDU, 4% SD NCBDU, 16% TJ NCBDU). Nine HIV seroconversions occurred over 18 months, IR: 1.357 per 100 person-years (95% CI: 0.470, 2.243); 7 in TJ NCBDU and 2 in SD CBDU. Out of 16 identified phylogenetic clusters, 9 (56%) had sequences from both the U.S. and Mexico (mixed-country). The age of three youngest mixed-country dyads (2018-2021) overlapped with the COVID-related US-Mexico border closure in 2020. One large mixed-country cluster (N = 15) continued to grow during the border closure (Re = 4.8, 95% Highest Posterior Density (HPD) 1.5-9.1) with 47% engaging in sex work. Interpretation: Amidst the COVID-19 pandemic and the border closure, cross-border HIV clusters grew. Efforts to end the HIV epidemic in the U.S. should take into account cross-border HIV-1 transmission from Tijuana. Mobile harm reduction services and coordination with municipal HIV programs to initiate anti-retroviral therapy and pre-exposure prophylaxisis are needed to reduce transmission. Funding: This research was supported by the James B. Pendleton Charitable Trust and the San Diego Center for AIDS Research.

2.
PLoS One ; 18(9): e0291367, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37751407

RESUMEN

OBJECTIVE: Identify system-level features in HIV migration within a host across body tissues. Evaluate heterogeneity in the presence and magnitude of these features across hosts. METHOD: Using HIV DNA deep sequencing data generated across multiple tissues from 8 people with HIV, we represent the complex dependencies of HIV migration among tissues as a network and model these networks using the family of exponential random graph models (ERGMs). ERGMs allow for the statistical assessment of whether network features occur more (or less) frequently in viral migration than might be expected by chance. The analysis investigates five potential features of the viral migration network: (1) bi-directional flow between tissues; (2) preferential migration among tissues in the same biological system; (3) heterogeneity in the level of viral migration related to HIV reservoir size; (4) hierarchical structure of migration; and (5) cyclical migration among several tissues. We calculate the Cohran's Q statistic to assess heterogeneity in the magnitude of the presence of these features across hosts. The analysis adjusts for missing data on body tissues. RESULTS: We observe strong evidence for bi-directional flow between tissues; migration among tissues in the same biological system; and hierarchical structure of the viral migration network. This analysis shows no evidence for differential level of viral migration with respect to the HIV reservoir size of a tissue. There is evidence that cyclical migration among three tissues occurs less frequent than expected given the amount of viral migration. The analysis also provides evidence for heterogeneity in the magnitude that these features are present across hosts. Adjusting for missing tissue data identifies system-level features within a host as well as heterogeneity in the presence of these features across hosts that are not detected when the analysis only considers the observed data. DISCUSSION: Identification of common features in viral migration may increase the efficiency of HIV cure efforts as it enables targeting specific processes.


Asunto(s)
Infecciones por VIH , Antígenos del Grupo Sanguíneo de Lewis , Humanos
3.
J Clin Invest ; 133(12)2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37317962

RESUMEN

Brain microglia (MG) may serve as a human immunodeficiency virus 1 (HIV) reservoir and ignite rebound viremia following cessation of antiretroviral therapy (ART), but they have yet to be proven to harbor replication-competent HIV. Here, we isolated brain myeloid cells (BrMCs) from nonhuman primates and rapid autopsy of people with HIV (PWH) on ART and sought evidence of persistent viral infection. BrMCs predominantly displayed microglial markers, in which up to 99.9% of the BrMCs were TMEM119+ MG. Total and integrated SIV or HIV DNA was detectable in the MG, with low levels of cell-associated viral RNA. Provirus in MG was highly sensitive to epigenetic inhibition. Outgrowth virus from parietal cortex MG in an individual with HIV productively infected both MG and PBMCs. This inducible, replication-competent virus and virus from basal ganglia proviral DNA were closely related but highly divergent from variants in peripheral compartments. Phenotyping studies characterized brain-derived virus as macrophage tropic based on the ability of the virus to infect cells expressing low levels of CD4. The lack of genetic diversity in virus from the brain suggests that this macrophage-tropic lineage quickly colonized brain regions. These data demonstrate that MG harbor replication-competent HIV and serve as a persistent reservoir in the brain.


Asunto(s)
Infecciones por VIH , VIH-1 , Animales , Humanos , Microglía , Encéfalo , Macrófagos , Provirus/genética , Infecciones por VIH/tratamiento farmacológico
4.
J Virol ; 97(6): e0054323, 2023 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-37184401

RESUMEN

HIV reservoirs persist in anatomic compartments despite antiretroviral therapy (ART). Characterizing archival HIV DNA in the central nervous system (CNS) and other tissues is crucial to inform cure strategies. We evaluated paired autopsy brain-frontal cortex (FC), occipital cortex (OCC), and basal ganglia (BG)-and peripheral lymphoid tissues from 63 people with HIV. Participants passed away while virally suppressed on ART at the last visit and without evidence of CNS opportunistic disease. We quantified total HIV DNA in all participants and obtained full-length HIV-envelope (FL HIV-env) sequences from a subset of 14 participants. We detected HIV DNA (gag) in most brain (65.1%) and all lymphoid tissues. Lymphoid tissues had higher HIV DNA levels than the brain (P < 0.01). Levels of HIV gag between BG and FC were similar (P > 0.2), while OCC had the lowest levels (P = 0.01). Females had higher HIV DNA levels in tissues than males (gag, P = 0.03; 2-LTR, P = 0.05), suggesting possible sex-associated mechanisms for HIV reservoir persistence. Most FL HIV-env sequences (n = 143) were intact, while 42 were defective. Clonal sequences were found in 8 out of 14 participants, and 1 participant had clonal defective sequences in the brain and spleen, suggestive of cell migration. From 10 donors with paired brain and lymphoid sequences, we observed evidence of compartmentalized sequences in 2 donors. Our data further the idea that the brain is a site for archival HIV DNA during ART where compartmentalized provirus may occur in a subset of people. Future studies assessing FL HIV-provirus and replication competence are needed to further evaluate the HIV reservoirs in tissues. IMPORTANCE HIV infection of the brain is associated with adverse neuropsychiatric outcomes, despite efficient antiretroviral treatment. HIV may persist in reservoirs in the brain and other tissues, which can seed virus replication if treatment is interrupted, representing a major challenge to cure HIV. We evaluated reservoirs and genetic features in postmortem brain and lymphoid tissues from people with HIV who passed away during suppressed HIV replication. We found a differential distribution of HIV reservoirs across brain regions which was lower than that in lymphoid tissues. We observed that most HIV reservoirs in tissues had intact envelope sequences, suggesting they could potentially generate replicative viruses. We found that women had higher HIV reservoir levels in brain and lymphoid tissues than men, suggesting possible sex-based mechanisms of maintenance of HIV reservoirs in tissues, warranting further investigation. Characterizing the archival HIV DNA in tissues is important to inform future HIV cure strategies.


Asunto(s)
Encéfalo , ADN Viral , VIH-1 , Tejido Linfoide , Femenino , Humanos , Masculino , Encéfalo/virología , ADN Viral/genética , Infecciones por VIH/virología , Provirus/genética , Bazo/virología , Persona de Mediana Edad , Tejido Linfoide/virología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , VIH-1/genética
5.
Salud Publica Mex ; 65(1, ene-feb): 10-18, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36750073

RESUMEN

OBJECTIVE: To interrogate the circulating SARS-CoV-2 lin-eages and recombinant variants in persons living in migrant shelters and persons who inject drugs (PWID). MATERIALS AND METHODS: We combined data from two studies with marginalized populations (migrants in shelters and persons who inject drugs) in Tijuana, Mexico. SARS-CoV-2 variants were identified on nasal swabs specimens and compared to publicly available genomes sampled in Mexico and California. RESULTS: All but 2 of the 10 lineages identified were predomi-nantly detected in North and Central America. Discrepan-cies between migrants and PWID can be explained by the temporal emergence and short time span of most of these lineages in the region. CONCLUSION: The results illustrate the temporo-spatial structure for SARS-CoV-2 lineage dispersal and the potential co-circulation of multiple lineages in high-risk populations with close social contacts. These conditions create the potential for recombination to take place in the California-Baja California border.


Asunto(s)
COVID-19 , Consumidores de Drogas , Abuso de Sustancias por Vía Intravenosa , Humanos , SARS-CoV-2 , México
6.
Reprod Health ; 19(1): 131, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35668524

RESUMEN

BACKGROUND: In the global debate around transactional sex little attention has concentrated on Brazil, despite ranking fourth globally in absolute number of girls married or co-habiting by the age of 15 years, and evidence showing that these unions often begin as age-disparate transactional sex (ADTS). This article contributes to filling this gap by exploring the personal beliefs and social norms related to ADTS in urban (favela) communities of Rio de Janeiro, Brazil between adult men (> 18 years) and girls and adolescents (G/A) (< 18 years) with a minimum 5-year age disparity. The primary objective of this study was to identify the social norms that promote and prevent ADTS, and the dynamics between individual beliefs and social norms, to provide contextualized recommendations to prevent ADTS in this setting. METHODS: An exploratory, sequential, mixed-methods design was used, starting with a qualitative phase that included semi-structured, in-depth interviews and focus groups, and a subsequent quantitative phase comprising of a community survey. The items for the quantitative questionnaires were developed based on the qualitative results. RESULTS: Mixed methods results indicate that in these communities ADTS is normalised and not considered exploitative. We identified three themes related to the reasons ADTS occurs: girls' responsibility, male desires and benefits of ADTS. Men's role in ADTS was largely minimised because of a general acceptance of a notion of masculinity characterised by hypersexuality and lack of impulse control. Individual beliefs, however, did not tend to align with these social norms. CONCLUSIONS: In this study, personal beliefs and social norms often did not align, suggesting that initiatives working to change personal or attitudes regarding ADTS may not lead to meaningful change in ADTS behaviours, and social norms interventions may be more effective. Our findings reinforce the need to develop programs tailored to local understandings of ADTS, targeting not only girls but also a wide range of actors. Interventions could also consider the structural factors acting in local and global contexts that promote or prevent ADTS.


This article explores the personal beliefs and social norms related to the exchange of sexual favours or relationships for material favours, gifts and/or support in some form, between adult men (> 18 years) and girls and adolescents (< 18 years) with a minimum 5-year age difference. We used interviews, focus groups and questionnaires to understand the factors that promote and prevent these sexual relationships between men and girls. Motivators for these relationships were often related to girls' responsibilities, male desires and the benefits of these relationships. Men's responsibility for their participation in these relationships with girls were often minimised due to a general acceptance of men as overly sexual and lacking impulse control. In this study, personal beliefs and social norms were often not aligned, suggesting that interventions focused on changing personal beliefs or attitudes about these sexual relationships may not be enough to change social norms. The findings highlight the need to develop solutions that consider a wider range of actors, instead of interventions focused only on girls. The study findings also support the need to further investigate how communities and shared expectations can influence sexual relationships in exchange for goods between adult men and girls and adolescents.


Asunto(s)
Conducta Sexual , Normas Sociales , Adolescente , Adulto , Brasil , Femenino , Grupos Focales , Humanos , Masculino , Matrimonio
7.
Viruses ; 14(5)2022 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-35632788

RESUMEN

The authors report on a possible direct exposure to SARS-CoV-2 from a COVID-19-positive individual to an adult horse. The individual, diagnosed with COVID-19 (Delta B.1.617.2), had daily contact to her two horses prior to and during the development of clinical disease. None of the two horses developed abnormal clinical signs or had detectable SARS-CoV-2 in blood, nasal secretion, or feces via RT-qPCR. However, one of the two horses showed close temporal seroconversion to SARS-CoV-2 using a protein-based ELISA and the plaque reduction neutralization test. The results suggest that horses can become silently infected with SARS-CoV-2 following close contact with humans infected with SARS-CoV-2. As a precautionary measure, humans infected with SARS-CoV-2 should avoid close contact with equids and other companion animals during the time of their illness to prevent viral transmission.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , COVID-19/veterinaria , Ensayo de Inmunoadsorción Enzimática , Femenino , Caballos , Seroconversión
8.
BMJ Glob Health ; 7(3)2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35277428

RESUMEN

INTRODUCTION: Migrants, especially those in temporary accommodations like camps and shelters, might be a vulnerable population during the COVID-19 pandemic, but little is known about the impact of the pandemic in these settings in low-income and middle-income countries. We assessed SARS-CoV-2 seropositivity and RNA prevalence, the correlates of seropositivity (emphasising socially determined conditions), and the socioeconomic impacts of the pandemic among migrants living in shelters in Tijuana, a city on the Mexico-US border. METHODS: We conducted a cross-sectional, non-probability survey of migrants living in shelters in Tijuana in November-December 2020 and February-April 2021. Participants completed a questionnaire and provided anterior nasal swab and blood samples for detection of SARS-CoV-2 RNA and antibodies (IgG and IgM), respectively. We explored whether SARS-CoV-2 infection was associated with sociodemographic and migration-related variables, access to sanitation, protective behaviours and health-related factors. RESULTS: Overall, 481 participants were enrolled, 67.7% from Northern Central America, 55.3% women, mean age 33.2 years. Seven (1.5%) participants had nasal swabs positive for SARS-CoV-2 RNA and 53.0% were SARS-CoV-2 seropositive. Avoiding public transportation (OR 0.59, 95% CI 0.39 to 0.90) and months living in Tijuana (OR 1.06, 95% CI 1.02 to 1.10) were associated with seropositivity. Sleeping on the streets or other risky places and having diabetes were marginally associated with seropositivity. Most participants (90.2%) had experienced some socioeconomic impact of the pandemic (eg, diminished income, job loss). CONCLUSION: Compared with results from other studies conducted in the general population in Mexico at a similar time, migrants living in shelters were at increased risk of acquiring SARS-CoV-2, and they suffered considerable adverse socioeconomic impacts as a consequence of the pandemic. Expanded public health and other social support systems are needed to protect migrants from COVID-19 and reduce health inequities.


Asunto(s)
COVID-19 , Migrantes , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , México/epidemiología , Pandemias , ARN Viral , SARS-CoV-2
9.
Lancet Reg Health Am ; 10: 100209, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36777692

RESUMEN

Background: Transactional sex between girls under 18 years-old and adult men at least ten years older, known as age-disparate transactional sex (ADTS), is an established risk factor for HIV, STI and early pregnancy among girls and women. Social norms or beliefs about what others expect from you and what others do can sustain behaviours such as ADTS even when individuals may be personally against them. In order to evaluate interventions to change social norms, validated instruments for measuring change in personal beliefs and social norms regarding ADTS are needed. Methods: Items for the Norms and Attitudes on Age-Disparate Transactional Sex Scale (NAATSS) were generated based on qualitative interviews and expert panel review. The reliability and validity of the NAATSS was tested in a representative sample (N = 431) from Brazilian favelas. Factor analysis assessed construct validity, Cronbach's alpha assessed reliability, and t-tests and analysis of variances tested hypothesized differences between gender, age, and previous experience with ADTS in both the social norms and personal beliefs domains. Findings: Factor analysis revealed three factors in each domain. The factors were labelled "Attributions to Girls' Behaviour" which has 5 items, "Men's Motivations" with 5 items, and "Girls' Readiness to have Sex" with 3 items. The subscales evidenced acceptable reliability with Cronbach's alphas ranging from 0.72 to 0.83 for the social norms subscales and 0.59 to 0.82 for the personal beliefs subscales. Interpretation: The items were developed based on qualitative research and expert rankings and the resulting Norms and Attitudes on ADTS Scale exhibits strong psychometric properties. Each of the three subscales within the two domains illustrate good factor structure, acceptable internal consistency reliability, and are supported by the significance of the hypothesized group differences. Funding: This work was supported by the OAK Foundation [grant number OCAY-16-188].

10.
PLoS One ; 16(11): e0260286, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34807963

RESUMEN

BACKGROUND: People who inject drugs may be at elevated SARS-CoV-2 risk due to their living conditions and/or exposures when seeking or using drugs. No study to date has reported upon risk factors for SARS-CoV-2 infection among people who inject drugs. METHODS AND FINDINGS: Between October, 2020 and June, 2021, participants aged ≥18 years from San Diego, California, USA and Tijuana, Baja California, Mexico who injected drugs within the last month underwent interviews and testing for SARS-CoV-2 RNA and antibodies. Binomial regressions identified correlates of SARS-CoV-2 seropositivity. RESULTS: Of 386 participants, SARS-CoV-2 seroprevalence was 36.3% (95% CI: 31.5%-41.1%); 92.1% had detectable IgM antibodies. Only 37.5% had previously been tested. Seroprevalence did not differ by country of residence. None tested RNA-positive. Most (89.5%) reported engaging in ≥1 protective behavior [e.g., facemasks (73.5%), social distancing (46.5%), or increasing handwashing/sanitizers (22.8%)]. In a multivariate model controlling for sex, older age, and Hispanic/Latinx/Mexican ethnicity were independently associated with SARS-CoV-2 seropositivity, as was engaging in sex work (AdjRR: 1.63; 95% CI: 1.18-2.27) and having been incarcerated in the past six months (AdjRR: 1.49; 95% CI: 0.97-2.27). Comorbidities and substance using behaviors were not associated with SARS-CoV-2 seropositivity. CONCLUSIONS: In this community-based study of people who inject drugs in the San Diego-Tijuana border region, over one third were SARS-CoV-2 seropositive, exceeding estimates from the general population in either city. We found no evidence that substance use behaviors were associated with an elevated risk of SARS-CoV-2 infection, but observed that circumstances in the risk environment, notably sex work and incarceration, were independently associated with higher SARS-CoV-2 seroprevalence. Our findings suggest that a binational policy response to COVID-19 mitigation is warranted beyond the closure of the U.S.-Mexico border. Furthermore, decriminalizing sex work and drug use could reduce the burden of COVID-19 among people who inject drugs.


Asunto(s)
Prueba Serológica para COVID-19/estadística & datos numéricos , COVID-19/epidemiología , Consumidores de Drogas/estadística & datos numéricos , Abuso de Sustancias por Vía Intravenosa/epidemiología , Adulto , Factores de Edad , COVID-19/diagnóstico , California , Femenino , Humanos , Masculino , México , Persona de Mediana Edad , Factores Raciales , Estudios Seroepidemiológicos , Factores Socioeconómicos
11.
Open Forum Infect Dis ; 8(7): ofab129, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34327248

RESUMEN

Together with protective measures, routine screening for severe acute respiratory syndrome coronavirus 2 infection helps provide a safe working environment. We evaluated a pooled nucleic acid testing strategy in a research laboratory. It allowed lab activity to be maintained and would save 25 920 person-hours and $1 684 800/year by increasing the margin of safety for returning to work.

12.
Nat Commun ; 12(1): 2938, 2021 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-34011939

RESUMEN

Pre-existing immunity to seasonal endemic coronaviruses could have profound consequences for antibody responses to SARS-CoV-2, induced from natural infection or vaccination. A first step to establish whether pre-existing responses can impact SARS-CoV-2 infection is to understand the nature and extent of cross-reactivity in humans to coronaviruses. Here we compare serum antibody and memory B cell responses to coronavirus spike proteins from pre-pandemic and SARS-CoV-2 convalescent donors using binding and functional assays. We show weak evidence of pre-existing SARS-CoV-2 cross-reactive serum antibodies in pre-pandemic donors. However, we find evidence of pre-existing cross-reactive memory B cells that are activated during SARS-CoV-2 infection. Monoclonal antibodies show varying degrees of cross-reactivity with betacoronaviruses, including SARS-CoV-1 and endemic coronaviruses. We identify one cross-reactive neutralizing antibody specific to the S2 subunit of the S protein. Our results suggest that pre-existing immunity to endemic coronaviruses should be considered in evaluating antibody responses to SARS-CoV-2.


Asunto(s)
Anticuerpos Antivirales/sangre , COVID-19/inmunología , Protección Cruzada/inmunología , SARS-CoV-2/inmunología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Linfocitos B/inmunología , Reacciones Cruzadas/inmunología , Femenino , Humanos , Memoria Inmunológica/inmunología , Masculino
13.
Biomacromolecules ; 22(3): 1231-1243, 2021 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-33539086

RESUMEN

Reverse transcription loop-mediated isothermal amplification (RT-LAMP) is a rapid and inexpensive isothermal alternative to the current gold standard reverse transcription quantitative polymerase chain reaction (RT-qPCR) for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, unlike RT-qPCR, there are no consensus detection regions or optimal RT-LAMP methods, and most protocols do not include internal controls to ensure reliability. Naked RNAs, plasmids, or even RNA from infectious COVID-19 patients have been used as external positive controls for RT-LAMP assays, but such reagents lack the stability required for full-process control. To overcome the lack of proper internal and external positive controls and the instability of the detection RNA, we developed virus-like particles (VLPs) using bacteriophage Qß and plant virus cowpea chlorotic mottle virus (CCMV) for the encapsidation of target RNA, namely a so-called SARS-CoV-2 LAMP detection module (SLDM). The target RNA is a truncated segment of the SARS-CoV-2 nucleocapsid (N) gene and human RNase P gene (internal control) as positive controls for RT-qPCR and RT-LAMP. Target RNAs stably encapsidated in Qß and CCMV VLPs were previously shown to function as full-process controls in RT-qPCR assays, and here we show that SLDMs can fulfill the same function for RT-LAMP and swab-to-test (direct RT-LAMP with heat lysis) assays. The SLDM was validated in a clinical setting, highlighting the promise of VLPs as positive controls for molecular assays.


Asunto(s)
Bromovirus , Prueba de Ácido Nucleico para COVID-19/normas , COVID-19 , Técnicas de Diagnóstico Molecular/normas , Técnicas de Amplificación de Ácido Nucleico/normas , SARS-CoV-2/genética , Bromovirus/química , Bromovirus/genética , COVID-19/diagnóstico , COVID-19/genética , Humanos
14.
ACS Nano ; 15(1): 1259-1272, 2021 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-33237727

RESUMEN

Coronavirus disease 2019 (COVID-19) is a highly transmissible disease that has affected more than 90% of the countries worldwide. At least 17 million individuals have been infected, and some countries are still battling first or second waves of the pandemic. Nucleic acid tests, especially reverse transcription polymerase chain reaction (RT-PCR), have become the workhorse for early detection of COVID-19 infection. Positive controls for the molecular assays have been developed to validate each test and to provide high accuracy. However, most available positive controls require cold-chain distribution and cannot serve as full-process control. To overcome these shortcomings, we report the production of biomimetic virus-like particles (VLPs) as SARS-CoV-2 positive controls. A SARS-CoV-2 detection module for RT-PCR was encapsidated into VLPs from a bacteriophage and a plant virus. The chimeric VLPs were obtained either by in vivo reconstitution and coexpression of the target detection module and coat proteins or by in vitro assembly of purified detection module RNA sequences and coat proteins. These VLP-based positive controls mimic SARS-CoV-2 packaged ribonucleic acid (RNA) while being noninfectious. Most importantly, we demonstrated that the positive controls are scalable, stable, and can serve broadly as controls, from RNA extraction to PCR in clinical settings.


Asunto(s)
Biomimética , Prueba de COVID-19/instrumentación , Prueba de COVID-19/métodos , COVID-19/diagnóstico , ARN Viral/análisis , Bacteriófagos , Bromovirus/genética , Humanos , Cinética , Nanotecnología/métodos , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2 , Vacunas de Partículas Similares a Virus
15.
J Acquir Immune Defic Syndr ; 85(4): 416-422, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33136738

RESUMEN

BACKGROUND: In low HIV prevalence settings, understanding the transmission dynamics and the impact of drug resistance is critical to curb down the epidemic. This study aims to explore the prevalence and dynamics of transmission of HIV drug-resistance mutations (DRMs) among key populations in Haiti. SETTINGS: Eligible participants (naive, treated) were selected from 7 key population friendly health care centers in Port-au-Prince, Haiti, from September 2018 to July 2019. METHODS: A total of 119 HIV-1 pol sequences were analyzed from men having sex with men (MSM), female sex workers (FSWs), and their sexual partners. Screening for HIV DRMs was performed using the Stanford University Drug Resistance Database. Phylogenetic and network analyses using HIV-TRACE software were performed to infer putative relationships and shared DRMs. RESULTS: Of the 119 participants, 62.2% were men (74/119), and 75.7% of them (56/74) reported MSM as a main risk factor. The overall DRM prevalence was 58.8% (70/119). A DRM was observed in 37.5% of MSM (21/56), 82.2% of FSWs (37/45), and 66.7% (12/18) among FSWs' clients. In a multivariate model, age and FSWs were significant predictors for DRMs (P = 0.001). Transmission network analysis found 24 of the 119 (20.2%) genetically linked individuals forming 8 clusters. Clustering participants were mostly MSM (15/24; 62.5%). Five clusters (62.5%) had shared DRMs, and K103N and M184V were the main shared mutations. CONCLUSIONS: High prevalence of HIV DRMs was observed among MSM, FSWs, and their clients in Port-au-Prince, Haiti. Network analysis revealed frequent DRM transmission among genetically linked individuals, highlighting the need for appropriate interventions to limit HIV transmission in these high-risk populations.


Asunto(s)
Fármacos Anti-VIH/farmacología , Farmacorresistencia Viral , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Adulto , Femenino , Haití/epidemiología , Homosexualidad Masculina , Humanos , Masculino , Oportunidad Relativa , Factores de Riesgo , Trabajadores Sexuales , Carga Viral , Adulto Joven
16.
bioRxiv ; 2020 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-32995770

RESUMEN

Pre-existing immune responses to seasonal endemic coronaviruses could have profound consequences for antibody responses to SARS-CoV-2, either induced in natural infection or through vaccination. Such consequences are well established in the influenza and flavivirus fields. A first step to establish whether pre-existing responses can impact SARS-CoV-2 infection is to understand the nature and extent of cross-reactivity in humans to coronaviruses. We compared serum antibody and memory B cell responses to coronavirus spike (S) proteins from pre-pandemic and SARS-CoV-2 convalescent donors using a series of binding and functional assays. We found weak evidence of pre-existing SARS-CoV-2 cross-reactive serum antibodies in pre-pandemic donors. However, we found stronger evidence of pre-existing cross-reactive memory B cells that were activated on SARS-CoV-2 infection. Monoclonal antibodies (mAbs) isolated from the donors showed varying degrees of cross-reactivity with betacoronaviruses, including SARS and endemic coronaviruses. None of the cross-reactive mAbs were neutralizing except for one that targeted the S2 subunit of the S protein. The results suggest that pre-existing immunity to endemic coronaviruses should be considered in evaluating antibody responses to SARS-CoV-2.

17.
Open Forum Infect Dis ; 7(8): ofaa325, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32875005

RESUMEN

RNA viruses (eg, Zika, Ebola, HIV) are often shed in male genital secretions. We evaluated the presence and level of SARS-CoV-2 RNA in semen, nasal secretion, and saliva collected after confirmed infection. SARS-CoV-2 RNA was not detected in semen 6-17 days after the onset of symptoms despite concomitant shedding in oral secretions.

18.
J Virol ; 94(15)2020 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-32434884

RESUMEN

If strategies currently in development succeed in eradicating HIV reservoirs in peripheral blood and lymphoid tissues, residual sources of virus may remain in anatomic compartments. Paired blood and semen samples were collected from 12 individuals enrolled in a randomized, double-blind, placebo-controlled therapeutic vaccine clinical trial in people with HIV (PWH) who began antiretroviral therapy (ART) during acute or early infection (ClinicalTrials registration no. NCT01859325). After the week 56 visit (postintervention), all participants interrupted ART. At the first available time points after viral rebound, we sequenced HIV-1 env (C2-V3), gag (p24), and pol (reverse transcriptase) regions amplified from cell-free HIV RNA in blood and seminal plasma using the MiSeq Illumina platform. Comprehensive sequence and phylogenetic analyses were performed to evaluate viral population structure, compartmentalization, and viral diversity in blood and seminal plasma. Compared to that in blood, HIV RNA rebound in semen occurred significantly later (median of 66 versus 42 days post-ART interruption, P < 0.01) and reached lower levels (median 164 versus 16,090 copies/ml, P < 0.01). Three of five participants with available sequencing data presented compartmentalized viral rebound between blood and semen in one HIV coding region. Despite early ART initiation, HIV RNA molecular diversity was higher in semen than in blood in all three coding regions for most participants. Higher HIV RNA molecular diversity in the genital tract (compared to that in blood plasma) and evidence of compartmentalization illustrate the distinct evolutionary dynamics between these two compartments after ART interruption. Future research should evaluate whether the genital compartment might contribute to viral rebound in some PWH interrupting ART.IMPORTANCE To cure HIV, we likely need to target the reservoirs in all anatomic compartments. Here, we used sophisticated statistical and phylogenetic methods to analyze blood and semen samples collected from 12 persons with HIV who began antiretroviral therapy (ART) during very early HIV infection and who interrupted their ART as part of a clinical trial. First, we found that HIV RNA rebound in semen occurred significantly later and reached lower levels than in blood. Second, we found that the virus in semen was genetically different in some participants compared to that in blood. Finally, we found increased HIV RNA molecular diversity in semen compared to that in blood in almost all study participants. These data suggest that the HIV RNA populations emerging from the genital compartment after ART interruption might not be the same as those emerging from blood plasma. Future research should evaluate whether the genital compartment might contribute to viral rebound in some people with HIV (PWH) interrupting ART.


Asunto(s)
Antirretrovirales/administración & dosificación , Infecciones por VIH , VIH-1/metabolismo , ARN Viral/metabolismo , Semen/metabolismo , Adulto , Método Doble Ciego , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Semen/virología
19.
AIDS ; 34(7): 1089-1092, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32287073

RESUMEN

: Rapid autopsy at the end of life in people with HIV (PWH) permits the preservation of valuable tissue specimens for subsequent study of HIV reservoirs. At our institution, we have developed a cohort of PWH who consent to a rapid autopsy to gather a wide range of fluids and tissues with the goal of advancing HIV cure research. The protocol for successfully performing these autopsies has required careful thought and development over months and years. We have now successfully performed six rapid autopsies and detail here our steps to build the study cohort, train and staff a team of more than a dozen personnel, and process and preserve hundreds of samples from each autopsy.


Asunto(s)
Autopsia/métodos , Patologia Forense , Infecciones por VIH/patología , Altruismo , Estudios de Cohortes , Humanos , Obtención de Tejidos y Órganos
20.
J Clin Invest ; 130(4): 1699-1712, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-31910162

RESUMEN

BACKGROUNDUnderstanding HIV dynamics across the human body is important for cure efforts. This goal has been hampered by technical difficulties and the challenge of obtaining fresh tissues.METHODSThis observational study evaluated 6 individuals with HIV (n = 4 with viral suppression using antiretroviral [ART] therapy; n = 2 with rebound viremia after stopping ART), who provided serial blood samples before death and their bodies for rapid autopsy. HIV reservoirs were characterized by digital droplet PCR, single-genome amplification, and sequencing of full-length (FL) envelope HIV. Phylogeographic methods were used to reconstruct HIV spread, and generalized linear models were tested for viral factors associated with dispersal.RESULTSAcross participants, HIV DNA levels varied from approximately 0 to 659 copies/106 cells (IQR: 22.9-126.5). A total of 605 intact FL env sequences were recovered in antemortem blood cells and across 28 tissues (IQR: 5-9). Sequence analysis showed (a) the emergence of large, identical, intact HIV RNA populations in blood after cessation of therapy, which repopulated tissues throughout the body; (b) that multiple sites acted as hubs for HIV dissemination but that blood and lymphoid tissues were the main source; (c) that viral exchanges occurred within brain areas and across the blood-brain barrier; and (d) that migration was associated with low HIV divergence between sites and greater diversity at the recipient site.CONCLUSIONHIV reservoirs persisted in all deep tissues, and blood was the main source of dispersal. This may explain why eliminating HIV susceptibility in circulating T cells via bone marrow transplants allowed some individuals with HIV to experience therapy-free remission, even though deeper tissue reservoirs were not targeted.TRIAL REGISTRATIONNot applicable.FUNDINGNIH grants P01 AI31385, P30 AI036214, AI131971-01, AI120009AI036214, HD094646, AI027763, AI134295, and AI68636.


Asunto(s)
Antirretrovirales/administración & dosificación , ADN Viral , Infecciones por VIH , VIH-1 , ARN Viral , Carga Viral , Anciano , ADN Viral/genética , ADN Viral/metabolismo , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , Infecciones por VIH/metabolismo , VIH-1/genética , VIH-1/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Especificidad de Órganos , ARN Viral/genética , ARN Viral/metabolismo
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