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1.
Medicine (Baltimore) ; 99(46): e23063, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33181671

RESUMO

HIV-1 persists indefinitely in multiple cellular reservoirs despite antiretroviral therapy. We previously demonstrated HIV-1 compartmentalization in kidney and urine. Here, we further characterized viruses in urine and when available, compared them to those present in semen from HIV-1 positive participants with detectable plasma viremia to further understand the viral dynamics in the upper and lower genitourinary tract.Blood and urine samples were obtained from 19 HIV-1 positive participants. Simultaneous semen samples were obtained from 16 of the 19 participants. HIV-1 envelope (env) gene sequences were obtained by single-genome amplification (SGA) and neighbor-joining trees were constructed using the Kimura 2-parameter model.HIV-1 env gene sequences were amplified from blood in 19/19 (100%) participants, urine in 18/19 (95%) participants, and semen in 12/16 (75%). In individuals from which both urine and semen samples were obtained, differences in viral shedding between the 2 sources were observed, where HIV-1 env sequences could only be amplified from either urine or semen. Longitudinal phylogenetic analysis of urine-derived env sequences from 1 participant demonstrated that urine clusters distinct from blood are maintained over time (20 weeks), consistent with viral compartmentalization and local replication. Comparison of urine and semen derived sequences demonstrated either virus compartmentalization or equilibration.Our results demonstrate that when present, viral compartmentalization in urine persists over time. Comparison of timing of viral shedding in urine and semen samples from our cohort suggest different viral kinetics between the upper and lower genitourinary tract and sequence analysis suggests that HIV-1 populations in urine and semen can either be imported from blood or produced locally.


Assuntos
Infecções por HIV/virologia , HIV-1/genética , Sêmen/virologia , Soro/virologia , Urina/virologia , Viremia/virologia , Adulto , Feminino , Amplificação de Genes , Infecções por HIV/sangue , Infecções por HIV/urina , Humanos , Masculino , Filogenia , Carga Viral , Viremia/sangue , Viremia/urina , Eliminação de Partículas Virais
3.
Nat Commun ; 11(1): 5493, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-33127906

RESUMO

The relationship between SARS-CoV-2 viral load and risk of disease progression remains largely undefined in coronavirus disease 2019 (COVID-19). Here, we quantify SARS-CoV-2 viral load from participants with a diverse range of COVID-19 disease severity, including those requiring hospitalization, outpatients with mild disease, and individuals with resolved infection. We detected SARS-CoV-2 plasma RNA in 27% of hospitalized participants, and 13% of outpatients diagnosed with COVID-19. Amongst the participants hospitalized with COVID-19, we report that a higher prevalence of detectable SARS-CoV-2 plasma viral load is associated with worse respiratory disease severity, lower absolute lymphocyte counts, and increased markers of inflammation, including C-reactive protein and IL-6. SARS-CoV-2 viral loads, especially plasma viremia, are associated with increased risk of mortality. Our data show that SARS-CoV-2 viral loads may aid in the risk stratification of patients with COVID-19, and therefore its role in disease pathogenesis should be further explored.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Adulto , Idoso , Anticorpos Antivirais/sangue , Betacoronavirus/genética , Betacoronavirus/crescimento & desenvolvimento , Biomarcadores/sangue , Proteína C-Reativa , Infecções por Coronavirus/sangue , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/patologia , Feminino , Hospitalização , Humanos , Inflamação/sangue , Inflamação/virologia , Interleucina-6/sangue , Estudos Longitudinais , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/mortalidade , Pneumonia Viral/patologia , RNA Viral/sangue , Índice de Gravidade de Doença , Carga Viral , Viremia/sangue , Viremia/virologia
4.
PLoS Pathog ; 16(10): e1008954, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33104758

RESUMO

Globally, 1.8 million children are living with HIV-1. While antiretroviral therapy (ART) has improved disease outcomes, it does not eliminate the latent HIV-1 reservoir. Interventions to delay or prevent viral rebound in the absence of ART would be highly beneficial for HIV-1-infected children who now must remain on daily ART throughout their lifespan. Here, we evaluated therapeutic Ad48-SIV prime, MVA-SIV boost immunization in combination with the TLR-7 agonist GS-986 in rhesus macaque (RM) infants orally infected with SIVmac251 at 4 weeks of age and treated with a triple ART regimen beginning 4 weeks after infection. We hypothesized immunization would enhance SIV-specific T cell responses during ART-mediated suppression of viremia. Compared to controls, vaccinated infants had greater magnitude SIV-specific T cell responses (mean of 3475 vs 69 IFN-γ spot forming cells (SFC) per 106 PBMCs, respectively, P = 0.01) with enhanced breadth of epitope recognition and increased CD8+ and CD4+ T cell polyfunctionality (P = 0.004 and P = 0.005, respectively). Additionally, SIV-specific gp120 antibodies against challenge and vaccine virus strains were significantly elevated following MVA boost (P = 0.02 and P < 0.001, respectively). GS-986 led to expected immune stimulation demonstrated by activation of monocytes and T cells 24 hours post-dose. Despite the vaccine-induced immune responses, levels of SIV DNA in peripheral and lymph node CD4+ T cells were not significantly different from controls and a similar time to viral rebound and viral load set point were observed following ART interruption in both groups. We demonstrate infant RMs mount a robust immunological response to this immunization, but vaccination alone was not sufficient to impact viral reservoir size or modulate rebound dynamics following ART release. Our findings hold promise for therapeutic vaccination as a part of a combination cure approach in children and highlight the importance of a pediatric model to evaluate HIV-1 cure interventions in this unique setting of immune development.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Vacinas contra a SAIDS/administração & dosagem , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Vírus da Imunodeficiência Símia/imunologia , Receptor 7 Toll-Like/agonistas , Vacinação/métodos , Viremia/tratamento farmacológico , Adenoviridae/genética , Animais , Animais Recém-Nascidos , Linfócitos T CD4-Positivos/virologia , Feminino , Vetores Genéticos , Macaca mulatta , Masculino , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Carga Viral , Viremia/imunologia , Viremia/virologia , Replicação Viral
5.
BMC Infect Dis ; 20(1): 773, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076866

RESUMO

BACKGROUND: Globally, the majority of people living with HIV have no or only limited access to HIV drug resistance testing to guide the selection of antiretroviral drugs. This is of particular concern for children and adolescents, who experience high rates of treatment failure. The GIVE MOVE trial assesses the clinical impact and cost-effectiveness of routinely providing genotypic resistance testing (GRT) to children and adolescents living with HIV who have an unsuppressed viral load (VL) while taking antiretroviral therapy (ART). METHODS: GIVE MOVE is an open-label randomised clinical trial enrolling children and adolescents (≥6 months to <19 years) living with HIV with a VL ≥400 copies/mL (c/mL) while taking first-line ART. Recruitment takes place at sites in Lesotho and Tanzania. Participants are randomised in a 1:1 allocation to a control arm receiving the standard of care (3 sessions of enhanced adherence counselling, a follow-up VL test, continuation of the same regimen upon viral resuppression or empiric selection of a new regimen upon sustained elevated viremia) and an intervention arm (GRT to inform onward treatment). The composite primary endpoint is the occurrence of any one or more of the following events during the 36 weeks of follow-up period: i) death due to any cause; ii) HIV- or ART-related hospital admission of ≥24 h duration; iii) new clinical World Health Organisation stage 4 event (excluding lymph node tuberculosis, stunting, oral or genital herpes simplex infection and oesophageal candidiasis); and iv) no documented VL <50 c/mL at 36 weeks follow-up. Secondary and exploratory endpoints assess additional health-related outcomes, and a nested study will assess the cost-effectiveness of the intervention. Enrolment of a total of 276 participants is planned, with an interim analysis scheduled after the first 138 participants have completed follow-up. DISCUSSION: This randomised clinical trial will assess if the availability of resistance testing improves clinical outcomes in children and adolescents with elevated viremia while taking ART. TRIAL REGISTRATION: This trial is registered with ClinicalTrials.gov ( NCT04233242 ; registered 18.01.2020). More information: www.givemove.org .


Assuntos
Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV/efeitos dos fármacos , Adolescente , Fármacos Anti-HIV/uso terapêutico , Criança , Pré-Escolar , Análise Custo-Benefício , Aconselhamento , Feminino , Genótipo , Herpes Genital , Humanos , Lactente , Lesoto , Estudos Longitudinais , Masculino , Tanzânia , Falha de Tratamento , Carga Viral , Viremia/tratamento farmacológico , Viremia/virologia
6.
PLoS One ; 15(10): e0240550, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33057418

RESUMO

Among people with perinatal HIV infection (PHIV), non-communicable diseases, such as chronic kidney disease, are increasing. Both HIV replication and antiretroviral therapy are recognised causes of renal impairment. Objective of the study is to describe the impact of viremia copy-years (VCY) and antiretroviral therapy on trend of estimated glomerular filtration rate (eGFR) in a cohort of adults with perinatal HIV infection. We conducted a multicentre observational study in sixty adults living with PHIV across a 9-year period, from January 2010 to December 2018. The mean values of eGFR were analysed at the first (T0) and last year of observation (T1). VCY was defined as the area under HIV-RNA curve during the study period. We analysed data according to antiretroviral therapy: tenofovir disoproxil (TDF), non-nucleoside reverse transcriptase inhibitors (NNRTI), boosted protease inhibitors (PI/b), integrase inhibitors (INI). We observed a mean overall eGFR reduction from 126.6 mL/min (95%CI: 119.6-133.5) to 105.0 mL/min (95%CI: 99.55-110.6) (p<0.001). Older age, higher baseline eGFR, higher VCY and longer exposure to INI treatment were associated with eGFR reduction at univariate analysis. In the multivariate model, older age (p = 0.039), baseline eGFR (p<0.001) and VCY (p = 0.069), were retained. We also observed a longer exposure to PI/b and INI in patients with lower control on HIV-RNA, expressed as VCY>2 log10. Our study outlines a progressive eGFR reduction in young adults with PHIV, related to the lower control on HIV-RNA VCY and related to aging.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Infecções por HIV/complicações , Insuficiência Renal Crônica/epidemiologia , Viremia/complicações , Idoso , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/fisiologia , HIV/genética , HIV/isolamento & purificação , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , Infecções por HIV/virologia , Humanos , Transmissão Vertical de Doença Infecciosa , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , RNA Viral/isolamento & purificação , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/fisiopatologia , Fatores de Risco , Carga Viral , Viremia/diagnóstico , Viremia/tratamento farmacológico , Viremia/virologia , Adulto Jovem
7.
Transplant Proc ; 52(9): 2637-2641, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33012543

RESUMO

Here we report a single-center cohort of 6 patients (4 kidney only, and 2 simultaneous liver/kidney transplants) diagnosed with COVID-19 at a median of 1.9 years (range = 0.2-9.3 years) post transplant. Five (of 6) patients required inpatient admission, 2 patients (mortality = 33%) died. Among those with mortality, an increased concentration of inflammatory biomarkers (interleukin-6 and C-reactive protein) was noted with a lack of response to interleukin-6 blockade, remdesivir, and/or convalescent plasma. None of the kidney-only transplants (4/6; 67%) had elevation in plasma donor-derived cell-free DNA above the previously published cut-off of 1%, suggesting absence of significant allo-immune injury. Four (of 5) admitted patients had detectable SARS-CoV-2 (severe acute respiratory syndrome-coronavirus 2) in blood on samples obtained at/during hospitalization. Of the 4 discharged patients, 2 patients with undetectable virus on repeat nasopharyngeal swabs had seroconversion with positive SARS-CoV-2 IgG formation at 30 to 48 days post infection. One patient had prolonged shedding of virus on nasopharyngeal swab at 28 days post discharge despite lack of symptoms. In this preliminary report, we find that immunocompromised transplant patients had higher rates of RNAemia (67%) than reported in the general population (15%), seeming absence of allo-immune injury despite systemic inflammation, and formation of IgG overtime after recovery from infection.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Hospedeiro Imunocomprometido/imunologia , Transplante de Rim/efeitos adversos , Pneumonia Viral/imunologia , Complicações Pós-Operatórias/imunologia , Adulto , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/terapia , Infecções por Coronavirus/virologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Imunização Passiva , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/virologia , Viremia/imunologia , Viremia/mortalidade , Viremia/virologia
8.
Pan Afr Med J ; 36: 185, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32952829

RESUMO

Introduction: the risk of dengue virus or its antibodies which can be transmitted through blood transfusion by asymptomatic individuals infected, has been a major concern all over the world. Dengue is an endemic disease in sub-Saharan Africa, particularly in Cameroon. The purpose of this study is to determine the frequency of dengue virus (DENV) infection among potential blood donors at Yaounde Jamot Hospital. Methods: serum samples were collected from 310 potential adult blood donors aged 18-57 years, who signed a written informed consent and completed the questionnaire between March 2019 and August 2019. This serum is used to screen for the presence of serological markers of DENV infection (NS1, IgM and IgG) using immunochromatographic tests (Zhuhai Encode Medical Engineering Co., Ltd, China). IgM/IgG positive samples were confirmed by enzyme-linked immunosorbent assays (ELISA). Results: the overall prevalence was 24.8% among potential blood donors were subdivided as follows: 4.5% (14/310), 12.3% (38/310) and 6.1% (19/310) showed mono-positivity to DENV-NS1 antigen, anti-DENV IgM and anti-DENV IgG antibodies respectively. 1.9% (6/310) of potential blood donors showed dual positivity to anti-DENV IgM antibodies and anti-DENV IgG antibodies. The presence of DENV-NS1 antigen show asymptomatic viremia of dengue at the time of donation, while the presence of IgG antibodies reflects the high endemicity of dengue disease in the city of Yaoundé. Conclusion: these findings demonstrate the high level of risk of the DENV transmission among potential blood donors to needy recipients, underscoring the importance of establishing dengue fever blood screening in different services and blood collection units in Cameroon to improve safety transfusion and control the dissemination of the DENV.


Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue , Vírus da Dengue/isolamento & purificação , Dengue/diagnóstico , Adolescente , Adulto , Camarões , Estudos Transversais , Dengue/sangue , Dengue/transmissão , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Viremia/diagnóstico , Viremia/virologia , Adulto Jovem
9.
Ann Ital Chir ; 91: 235-238, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32877383

RESUMO

The present pandemic caused by the SARS COV-2 coronavirus is still ongoing, although it is registered a slowdown in the spread for new cases. The main environmental route of transmission of SARS-CoV-2 is through droplets and fomites or surfaces, but there is a potential risk of virus spread also in smaller aerosols during various medical procedures causing airborne transmission. To date, no information is available on the risk of contagion from the peritoneal fluid with which surgeons can come into contact during the abdominal surgery on COVID-19 patients. We have investigated the presence of SARS-CoV-2 RNA in the peritoneal cavity of patients affected by COVID-19, intraoperatively and postoperatively. KEY WORDS: Covid-19, Laparotomy, Surgery.


Assuntos
Líquido Ascítico/virologia , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/transmissão , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Perfuração Intestinal/cirurgia , Laparotomia , Pandemias , Pneumonia Viral/transmissão , Doenças do Colo Sigmoide/cirurgia , Viremia/transmissão , Aerossóis , Idoso de 80 Anos ou mais , Infecções por Coronavirus/sangue , Infecções por Coronavirus/complicações , Infecções por Coronavirus/prevenção & controle , Estudos Transversais , Divertículo/complicações , Evolução Fatal , Feminino , Humanos , Perfuração Intestinal/sangue , Perfuração Intestinal/complicações , Perfuração Intestinal/virologia , Período Intraoperatório , Nasofaringe/virologia , Pandemias/prevenção & controle , Pneumonia Viral/sangue , Pneumonia Viral/complicações , Pneumonia Viral/prevenção & controle , Período Pós-Operatório , Estudos Prospectivos , RNA Viral/isolamento & purificação , Risco , Soro/virologia , Doenças do Colo Sigmoide/sangue , Doenças do Colo Sigmoide/complicações , Doenças do Colo Sigmoide/virologia , Viremia/virologia
10.
Pan Afr Med J ; 36: 188, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32952832

RESUMO

COVID-19, caused by SARS-CoV-2 is a tester of the immune system. While it spares the healthy, it brings severe morbidity and in a few cases, mortality to its victims. This article aims at critically reviewing the key virulence factors of COVID-19 which are the viremia, cellular oxidation and immune dysfunction. The averse economic effect of certain disease control measures such as national lock-downs and social distancing, though beneficial, makes them unsustainable. Worse still is the fact that wild animals and domestic pets are carriers of SARS-CoV-2 suggesting that the disease would take longer than expected to be eradicated globally. A better understanding of the pathological dynamics of COVID-19 would help the general populace to prepare for possible infection by the invisible enemy. While the world prospects for vaccines and therapeutic agents against the SARS-CoV-2, clinicians should also seek to modulate the immune system for optimum performance. Immunoprophylactic and immunomodulatory strategies are recommended for the different strata of stakeholders combating the pandemic with the hope that morbidities and mortalities associated with COVID-19 would be drastically reduced.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/virologia , Sistema Imunitário/virologia , Pneumonia Viral/virologia , Animais , Betacoronavirus/imunologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Humanos , Oxirredução , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Viremia/epidemiologia , Viremia/virologia
11.
Viruses ; 12(9)2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32962125

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents a global health emergency. To improve the understanding of the systemic component of SARS-CoV-2, we investigated if viral load dynamics in plasma and respiratory samples are associated with antibody response and severity of coronavirus disease 2019 (COVID-19). SARS-CoV-2 RNA was found in plasma samples from 14 (44%) out of 32 patients. RNAemia was detected in 5 out of 6 fatal cases. Peak IgG values were significantly lower in mild/moderate than in severe (0.6 (interquartile range, IQR, 0.4-3.2) vs. 11.8 (IQR, 9.9-13.0), adjusted p = 0.003) or critical cases (11.29 (IQR, 8.3-12.0), adjusted p = 0.042). IgG titers were significantly associated with virus Ct (Cycle threshold) value in plasma and respiratory specimens ((ß = 0.4, 95% CI (confidence interval, 0.2; 0.5), p < 0.001 and ß = 0.5, 95% CI (0.2; 0.6), p = 0.002). A classification as severe or a critical case was additionally inversely associated with Ct values in plasma in comparison to mild/moderate cases (ß = -3.3, 95% CI (-5.8; 0.8), p = 0.024 and ß = -4.4, 95% CI (-7.2; 1.6), p = 0.007, respectively). Based on the present data, our hypothesis is that the early stage of SARS-CoV-2 infection is characterized by a primary RNAemia, as a potential manifestation of a systemic infection. Additionally, the viral load in plasma seems to be associated with a worse disease outcome.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , RNA Viral/sangue , Idoso , Betacoronavirus/genética , Betacoronavirus/imunologia , Infecções por Coronavirus/sangue , Infecções por Coronavirus/patologia , Feminino , Alemanha/epidemiologia , Hospitalização , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/patologia , RNA Viral/análise , Sistema Respiratório/virologia , Índice de Gravidade de Doença , Carga Viral , Viremia/sangue , Viremia/patologia , Viremia/virologia
12.
J Virol ; 94(21)2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32817214

RESUMO

The "shock-and-kill" human immunodeficiency virus type 1 (HIV-1) cure strategy involves latency reversal followed by immune-mediated clearance of infected cells. We have previously shown that activation of the noncanonical NF-κB pathway using an inhibitor of apoptosis (IAP), AZD5582, reverses HIV/simian immunodeficiency virus (SIV) latency. Here, we combined AZD5582 with bispecific HIVxCD3 DART molecules to determine the impact of this approach on persistence. Rhesus macaques (RMs) (n = 13) were infected with simian/human immunodeficiency virus SHIV.C.CH505.375H.dCT, and triple antiretroviral therapy (ART) was initiated after 16 weeks. After 42 weeks of ART, 8 RMs received a cocktail of 3 HIVxCD3 DART molecules having human A32, 7B2, or PGT145 anti-HIV-1 envelope (Env) specificities paired with a human anti-CD3 specificity that is rhesus cross-reactive. The remaining 5 ART-suppressed RMs served as controls. For 10 weeks, a DART molecule cocktail was administered weekly (each molecule at 1 mg/kg of body weight), followed 2 days later by AZD5582 (0.1 mg/kg). DART molecule serum concentrations were well above those considered adequate for redirected killing activity against Env-expressing target cells but began to decline after 3 to 6 weekly doses, coincident with the development of antidrug antibodies (ADAs) against each of the DART molecules. The combination of AZD5582 and the DART molecule cocktail did not increase on-ART viremia or cell-associated SHIV RNA in CD4+ T cells and did not reduce the viral reservoir size in animals on ART. The lack of latency reversal in the model used in this study may be related to low pre-ART viral loads (median, <105 copies/ml) and low preintervention reservoir sizes (median, <102 SHIV DNA copies/million blood CD4+ T cells). Future studies to assess the efficacy of Env-targeting DART molecules or other clearance agents to reduce viral reservoirs after latency reversal may be more suited to models that better minimize immunogenicity and have a greater viral burden.IMPORTANCE The most significant barrier to an HIV-1 cure is the existence of the latently infected viral reservoir that gives rise to rebound viremia upon cessation of ART. Here, we tested a novel combination approach of latency reversal with AZD5582 and clearance with bispecific HIVxCD3 DART molecules in SHIV.C.CH505-infected, ART-suppressed rhesus macaques. We demonstrate that the DART molecules were not capable of clearing infected cells in vivo, attributed to the lack of quantifiable latency reversal in this model with low levels of persistent SHIV DNA prior to intervention as well as DART molecule immunogenicity.


Assuntos
Alquinos/farmacologia , Antirretrovirais/farmacologia , Anticorpos Neutralizantes/farmacologia , Anticorpos Antivirais/farmacologia , Infecções por HIV/tratamento farmacológico , Oligopeptídeos/farmacologia , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Viremia/tratamento farmacológico , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Feminino , Regulação da Expressão Gênica , Infecções por HIV/genética , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/crescimento & desenvolvimento , HIV-1/imunologia , Humanos , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/imunologia , Macaca mulatta , NF-kappa B/genética , NF-kappa B/imunologia , Vírus Reordenados/efeitos dos fármacos , Vírus Reordenados/crescimento & desenvolvimento , Vírus Reordenados/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/genética , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Vírus da Imunodeficiência Símia/crescimento & desenvolvimento , Vírus da Imunodeficiência Símia/imunologia , Carga Viral/efeitos dos fármacos , Viremia/genética , Viremia/imunologia , Viremia/virologia , Latência Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
13.
J Virol ; 94(21)2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32847848

RESUMO

Zika virus (ZIKV) can establish infection in immune privileged sites such as the testes, eye, and placenta. Whether ZIKV infection of white blood cells is required for dissemination of the virus to immune privileged sites has not been definitively shown. To assess whether initial ZIKV replication in myeloid cell populations is critical for dissemination during acute infection, recombinant ZIKVs were generated that could not replicate in these specific cells. ZIKV was cell restricted by insertion of a complementary sequence to a myeloid-specific microRNA in the 3' untranslated region. Following inoculation of a highly sensitive immunodeficient mouse model, crucial immune parameters, such as quantification of leukocyte cell subsets, cytokine and chemokine secretion, and viremia, were assessed. Decreased neutrophil numbers in the spleen were observed during acute infection with myeloid-restricted ZIKV that precluded the generation of viremia and viral dissemination to peripheral organs. Mice inoculated with a nontarget microRNA control ZIKV demonstrated increased expression of key cytokines and chemokines critical for neutrophil and monocyte recruitment and increased neutrophil influx in the spleen. In addition, ZIKV-infected Ly6Chi monocytes were identified in vivo in the spleen. Mice inoculated with myeloid-restricted ZIKV had a decrease in Ly6Chi ZIKV RNA-positive monocytes and a lack of inflammatory cytokine production compared to mice inoculated with control ZIKV.IMPORTANCE Myeloid cells, including monocytes, play a crucial role in immune responses to pathogens. Monocytes have also been implicated as "Trojan horses" during viral infections, carrying infectious virus particles to immune privileged sites and/or to sites protected by physical blood-tissue barriers, such as the blood-testis barrier and the blood-brain barrier. In this study, we found that myeloid cells are crucial to Zika virus (ZIKV) pathogenesis. By engineering ZIKV clones to encode myeloid-specific microRNA target sequences, viral replication was inhibited in myeloid cells by harnessing the RNA interference pathway. Severely immunodeficient mice inoculated with myeloid-restricted ZIKV did not demonstrate clinical signs of disease and survived infection. Furthermore, viral dissemination to peripheral organs was not observed in these mice. Lastly, we identified Ly6Cmid/hi murine monocytes as the major myeloid cell population that disseminates ZIKV.


Assuntos
Linhagem da Célula/imunologia , Hospedeiro Imunocomprometido , Células Mieloides/imunologia , Viremia/imunologia , Replicação Viral/imunologia , Infecção por Zika virus/imunologia , Zika virus/imunologia , Animais , Antígenos Ly/genética , Antígenos Ly/imunologia , Encéfalo/imunologia , Encéfalo/patologia , Encéfalo/virologia , Linhagem da Célula/genética , Citocinas/genética , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Masculino , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , MicroRNAs/imunologia , Monócitos/imunologia , Monócitos/patologia , Monócitos/virologia , Células Mieloides/classificação , Células Mieloides/patologia , Células Mieloides/virologia , Neutrófilos/imunologia , Neutrófilos/patologia , Neutrófilos/virologia , RNA Viral/genética , RNA Viral/imunologia , Transdução de Sinais , Baço/imunologia , Baço/patologia , Baço/virologia , Testículo/imunologia , Testículo/patologia , Testículo/virologia , Viremia/genética , Viremia/patologia , Viremia/virologia , Zika virus/patogenicidade , Infecção por Zika virus/genética , Infecção por Zika virus/patologia , Infecção por Zika virus/virologia
14.
J Infect Chemother ; 26(11): 1220-1223, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32792249

RESUMO

Coronavirus disease 2019 (COVID-19) is spreading worldwide and poses an imminent threat to public health. We encountered 2 cases of COVID-19 with progression resulting in severe respiratory failure and improvement without any specific treatment. To examine the course of infection, we performed reverse-transcription (RT) polymerase chain reaction assay with serum specimens, and serum SARS-CoV-2 RNA was detected in both cases when body temperature increased and respiratory status deteriorated. We, then examined, retrospectively and prospectively, the clinical course during hospitalization by performing serial examinations of serum SARS-CoV-2 RNA status. The findings from our cases suggest that not only is detection of viremia useful as a predictive marker of severity, but also serial serum SARS-CoV-2 RNA results can be helpful for predicting the clinical course.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/complicações , Pneumonia Viral/complicações , RNA Viral/sangue , Insuficiência Respiratória/diagnóstico , Viremia/diagnóstico , Adulto , Idoso , Betacoronavirus/genética , Técnicas de Laboratório Clínico , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Humanos , Masculino , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , RNA Viral/isolamento & purificação , Insuficiência Respiratória/sangue , Insuficiência Respiratória/virologia , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença , Fatores de Tempo , Viremia/complicações , Viremia/virologia
15.
PLoS Pathog ; 16(8): e1008791, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32841299

RESUMO

During antiretroviral therapy (ART) that suppresses HIV replication to below the limit-of-quantification, virions produced during ART can be detected at low frequencies in the plasma, termed residual viremia (RV). We hypothesized that a reservoir of HIV-infected cells actively produce and release virions during ART that are potentially infectious, and that following ART-interruption, these virions can complete full-cycles of replication and contribute to rebound viremia. Therefore, we studied the dynamics of RV sequence variants in 3 participants who initiated ART after ~3 years of infection and were ART-suppressed for >6 years prior to self-initiated ART-interruptions. Longitudinal RV C2V5env sequences were compared to sequences from pre-ART plasma, supernatants of quantitative viral outgrowth assays (QVOA) of cells collected during ART, post-ART-interruption plasma, and ART-re-suppression plasma. Identical, "putatively clonal," RV sequences comprised 8-84% of sequences from each timepoint. The majority of RV sequences were genetically similar to those from plasma collected just prior to ART-initiation, but as the duration of ART-suppression increased, an increasing proportion of RV variants were similar to sequences from earlier in infection. Identical sequences were detected in RV over a median of 3 years (range: 0.3-8.2) of ART-suppression. RV sequences were identical to pre-ART plasma viruses (5%), infectious viruses induced in QVOA (4%) and rebound viruses (5%) (total n = 21/154 (14%) across the 3 participants). RV sequences identical to ART-interruption "rebound" sequences were detected 0.1-7.4 years prior to ART-interruption. RV variant prevalence and persistence were not associated with detection of the variant among rebound sequences. Shortly after ART-re-suppression, variants that had been replicating during ART-interruptions were detected as RV (n = 5). These studies show a dynamic, virion-producing HIV reservoir that contributes to rekindling infection upon ART-interruption. The persistence of identical RV variants over years suggests that a subpopulation of HIV-infected clones frequently or continuously produce virions that may resist immune clearance; this suggests that cure strategies should target this active as well as latent reservoirs.


Assuntos
Antirretrovirais/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Plasma/virologia , Viremia/epidemiologia , Replicação Viral , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Incidência , Plasma/efeitos dos fármacos , Plasma/imunologia , Estudos Retrospectivos , Estados Unidos/epidemiologia , Carga Viral , Viremia/virologia , Latência Viral , Suspensão de Tratamento
16.
Nature ; 585(7825): 414-419, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32641828

RESUMO

Zika virus (ZIKV) belongs to the family Flaviviridae, and is related to other viruses that cause human diseases. Unlike other flaviviruses, ZIKV infection can cause congenital neurological disorders and replicates efficiently in reproductive tissues1-3. Here we show that the envelope protein (E) of ZIKV is polyubiquitinated by the E3 ubiquitin ligase TRIM7 through Lys63 (K63)-linked polyubiquitination. Accordingly, ZIKV replicates less efficiently in the brain and reproductive tissues of Trim7-/- mice. Ubiquitinated E is present on infectious virions of ZIKV when they are released from specific cell types, and enhances virus attachment and entry into cells. Specifically, K63-linked polyubiquitin chains directly interact with the TIM1 (also known as HAVCR1) receptor of host cells, which enhances virus entry in cells as well as in brain tissue in vivo. Recombinant ZIKV mutants that lack ubiquitination are attenuated in human cells and in wild-type mice, but not in live mosquitoes. Monoclonal antibodies against K63-linked polyubiquitin specifically neutralize ZIKV and reduce viraemia in mice. Our results demonstrate that the ubiquitination of ZIKV E is an important determinant of virus entry, tropism and pathogenesis.


Assuntos
Ubiquitinação , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus , Zika virus/metabolismo , Zika virus/patogenicidade , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Encéfalo/metabolismo , Linhagem Celular , Culicidae/citologia , Culicidae/virologia , Endossomos/metabolismo , Feminino , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Humanos , Masculino , Fusão de Membrana , Camundongos , Especificidade de Órgãos , Poliubiquitina/imunologia , Poliubiquitina/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Tropismo Viral , Viremia/imunologia , Viremia/prevenção & controle , Viremia/virologia , Replicação Viral , Zika virus/química , Zika virus/genética , Infecção por Zika virus/prevenção & controle , Infecção por Zika virus/virologia
18.
J Virol ; 94(19)2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32699086

RESUMO

Classical swine fever virus (CSFV) contains a specific motif within the E2 glycoprotein that differs between strains of different virulence. In the highly virulent CSFV strain Koslov, this motif comprises residues S763/L764 in the polyprotein. However, L763/P764 represent the predominant alleles in published CSFV genomes. In this study, changes were introduced into the CSFV strain Koslov (here called vKos_SL) to generate modified CSFVs with substitutions at residues 763 and/or 764 (vKos_LL, vKos_SP, and vKos_LP). The properties of these mutant viruses, in comparison to those of vKos_SL, were determined in pigs. Each of the viruses was virulent and induced typical clinical signs of CSF, but the vKos_LP strain produced them significantly earlier. Full-length CSFV cDNA amplicons (12.3 kb) derived from sera of infected pigs were deep sequenced and cloned to reveal the individual haplotypes that contributed to the single-nucleotide polymorphism (SNP) profiles observed in the virus population. The SNP profiles for vKos_SL and vKos_LL displayed low-level heterogeneity across the entire genome, whereas vKos_SP and vKos_LP displayed limited diversity with a few high-frequency SNPs. This indicated that vKos_SL and vKos_LL exhibited a higher level of fitness in the host and more stability at the consensus level, whereas several consensus changes were observed in the vKos_SP and vKos_LP sequences, pointing to adaptation. For each virus, only a subset of the variants present within the virus inoculums were maintained in the infected pigs. No clear tissue-dependent quasispecies differentiation occurred within inoculated pigs; however, clear evidence for transmission bottlenecks to contact animals was observed, with subsequent loss of sequence diversity.IMPORTANCE The surface-exposed E2 protein of classical swine fever virus is required for its interaction with host cells. A short motif within this protein varies between strains of different virulence. The importance of two particular amino acid residues in determining the properties of a highly virulent strain of the virus has been analyzed. Each of the different viruses tested proved highly virulent, but one of them produced earlier, but not more severe, disease. By analyzing the virus genomes present within infected pigs, it was found that the viruses which replicated within inoculated animals were only a subset of those within the virus inoculum. Furthermore, following contact transmission, it was shown that a very restricted set of viruses had transferred between animals. There were no significant differences in the virus populations present in various tissues of the infected animals. These results indicate mechanisms of virus population change during transmission between animals.


Assuntos
Vírus da Febre Suína Clássica/genética , Peste Suína Clássica/transmissão , Peste Suína Clássica/virologia , Animais , Linhagem Celular , Peste Suína Clássica/mortalidade , Vírus da Febre Suína Clássica/classificação , Vírus da Febre Suína Clássica/patogenicidade , Vírus de DNA/genética , DNA Complementar/genética , Genoma Viral , Glicoproteínas/genética , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Polimorfismo de Nucleotídeo Único , RNA Viral , Suínos , Proteínas do Envelope Viral/genética , Viremia/virologia , Virulência
19.
Sci Rep ; 10(1): 12561, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32724103

RESUMO

The present manuscript deals with experimental infections of bonnet macaques (Macaca radiata) to study disease progression for better insights into the Kyasanur Forest Disease (KFD) pathogenesis and transmission. Experimentally, 10 monkeys were inoculated with KFD virus (KFDV) (high or low dose) and were regularly monitored and sampled for various body fluids and tissues at preset time points. We found that only 2 out of the 10 animals showed marked clinical signs becoming moribund, both in the low dose group, even though viremia, virus shedding in the secretions and excretions were evident in all inoculated monkeys. Anti-KFDV immunoglobulin (Ig)M antibody response was observed around a week after inoculation and anti-KFDV IgG antibody response after two weeks. Anaemia, leucopenia, thrombocytopenia, monocytosis, increase in average clotting time, and reduction in the serum protein levels were evident. The virus could be re-isolated from the skin during the viremic period. The persistence of viral RNA in the gastrointestinal tract and lymph nodes was seen up to 53 and 81 days respectively. Neuro-invasion was observed only in moribund macaques. Re-challenge with the virus after 21 days of initial inoculation in a monkey did not result in virus shedding or immune response boosting.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Doença da Floresta de Kyasanur/veterinária , Doenças dos Macacos/sangue , Viremia/veterinária , Animais , Vírus da Encefalite Transmitidos por Carrapatos/genética , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Cinética , Doença da Floresta de Kyasanur/sangue , Doença da Floresta de Kyasanur/virologia , Macaca radiata/sangue , Macaca radiata/virologia , Doenças dos Macacos/virologia , Viremia/sangue , Viremia/virologia
20.
Transplant Proc ; 52(6): 1762-1768, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32611487

RESUMO

BACKGROUND: Prevention and early detection of BK polyomavirus (BKV) infection is important for long-term kidney graft survival; hence, pretransplant screening methods are essential to identify recipients at high risk for BKV infection. This study investigated the association of pretransplant donor and recipient BKV antibody status with the occurrence of post-transplant BKV infection. METHODS: We prospectively enrolled 47 adult living donor kidney transplant pairs from December 2014 to January 2016. Recipient and donor pretransplant BKV antibody titer was measured by hemagglutination inhibition (HI) test. Donor and recipient median HI titer of 1:20 was used as a cutoff to define seropositivity. Recipients were divided into 2 groups (BKV antibody donor-seropositive/recipient-seronegative (D+/R-) and non-D+/R-). Urinary cytology was used to screen for BKV infection. Plasma polymerase chain reaction testing for BKV DNA was used when decoy cells in urine were persistently detected. RESULTS: Nine (19.2%) of 47 patients belonged to the D+/R- group. Decoy cells were observed in 32 recipients (68.1%) during follow-up. BK viremia occurred in 3 (6.4%) cases. The maximum decoy cell count was significantly higher in the D+/R- group than in the non-D+/R- group (P = .0002). Decoy-cell-free survival was significantly shorter in the D+/R- group (P = .0220). Multivariate analysis identified only BKV antibody serostatus as an independent risk factor for decoy cell appearance (P = .0491). CONCLUSIONS: Pretransplant donor and recipient BKV antibody status was associated with higher maximum decoy cell count and shorter decoy-cell-free survival after kidney transplantation.


Assuntos
Anticorpos Antivirais/sangue , Vírus BK/imunologia , Complicações Pós-Operatórias/imunologia , Insuficiência Renal/sangue , Doadores de Tecidos/estatística & dados numéricos , Adulto , Anticorpos Antivirais/imunologia , Feminino , Humanos , Rim/imunologia , Rim/virologia , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Infecções por Polyomavirus/sangue , Infecções por Polyomavirus/imunologia , Infecções por Polyomavirus/virologia , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/virologia , Período Pré-Operatório , Estudos Prospectivos , Insuficiência Renal/imunologia , Insuficiência Renal/cirurgia , Fatores de Risco , Transplantes/imunologia , Transplantes/virologia , Infecções Tumorais por Vírus/sangue , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/virologia , Viremia/sangue , Viremia/imunologia , Viremia/virologia
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