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1.
Viruses ; 16(6)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38932255

RESUMO

Quantification of Torquetenovirus (TTV) viremia is becoming important for evaluating the status of the immune system in solid organ transplant recipients, monitoring the appearance of post-transplant complications, and controlling the efficacy of maintenance immunosuppressive therapy. Thus, diagnostic approaches able to scale up TTV quantification are needed. Here, we report on the development and validation of a real-time PCR assay for TTV quantification on the Hologic Panther Fusion® System by utilizing its open-access channel. The manual real-time PCR previously developed in our laboratories was optimized to detect TTV DNA on the Hologic Panther Fusion® System. The assay was validated using clinical samples. The automated TTV assay has a limit of detection of 1.6 log copies per ml of serum. Using 112 samples previously tested via manual real-time PCR, the concordance in TTV detection was 93% between the assays. When the TTV levels were compared, the overall agreement between the methods, as assessed using Passing-Bablok linear regression and Bland-Altman analyses, was excellent. In summary, we validated a highly sensitive and accurate method for the diagnostic use of TTV quantification on a fully automated Hologic Panther Fusion® System. This will greatly improve the turnaround time for TTV testing and better support the laboratory diagnosis of this new viral biomarker.


Assuntos
Infecções por Vírus de DNA , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral , Viremia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Viremia/diagnóstico , Viremia/virologia , Humanos , Carga Viral/métodos , Infecções por Vírus de DNA/diagnóstico , Infecções por Vírus de DNA/virologia , Sensibilidade e Especificidade , Torque teno virus/genética , Torque teno virus/isolamento & purificação , DNA Viral/genética , DNA Viral/sangue , Limite de Detecção , Reprodutibilidade dos Testes , Automação Laboratorial/métodos
2.
Bull Math Biol ; 86(7): 85, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853189

RESUMO

How viral infections develop can change based on the number of viruses initially entering the body. The understanding of the impacts of infection doses remains incomplete, in part due to challenging constraints, and a lack of research. Gaining more insights is crucial regarding the measles virus (MV). The higher the MV infection dose, the earlier the peak of acute viremia, but the magnitude of the peak viremia remains almost constant. Measles is highly contagious, causes immunosuppression such as lymphopenia, and contributes substantially to childhood morbidity and mortality. This work investigated mechanisms underlying the observed wild-type measles infection dose responses in cynomolgus monkeys. We fitted longitudinal data on viremia using maximum likelihood estimation, and used the Akaike Information Criterion (AIC) to evaluate relevant biological hypotheses and their respective model parameterizations. The lowest AIC indicates a linear relationship between the infection dose, the initial viral load, and the initial number of activated MV-specific T cells. Early peak viremia is associated with high initial number of activated MV-specific T cells. Thus, when MV infection dose increases, the initial viremia and associated immune cell stimulation increase, and reduce the time it takes for T cell killing to be sufficient, thereby allowing dose-independent peaks for viremia, MV-specific T cells, and lymphocyte depletion. Together, these results suggest that the development of measles depends on virus-host interactions at the start and the efficiency of viral control by cellular immunity. These relationships are additional motivations for prevention, vaccination, and early treatment for measles.


Assuntos
Macaca fascicularis , Conceitos Matemáticos , Vírus do Sarampo , Sarampo , Carga Viral , Viremia , Sarampo/imunologia , Sarampo/transmissão , Sarampo/prevenção & controle , Sarampo/virologia , Sarampo/epidemiologia , Animais , Viremia/imunologia , Viremia/virologia , Vírus do Sarampo/imunologia , Vírus do Sarampo/patogenicidade , Vírus do Sarampo/fisiologia , Funções Verossimilhança , Humanos , Modelos Imunológicos , Modelos Biológicos , Linfócitos T/imunologia , Ativação Linfocitária
3.
Nat Commun ; 15(1): 4813, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844461

RESUMO

Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) poses a major threat to the global swine industry, yet effective prevention and control measures remain elusive. This study unveils Nitazoxanide (NTZ) as a potent inhibitor of PRRSV both in vitro and in vivo. Through High-Throughput Screening techniques, 16 potential anti-PRRSV compounds are identified from a library comprising FDA-approved and pharmacopeial drugs. We show that NTZ displays strong efficacy in reducing PRRSV proliferation and transmission in a swine model, alleviating viremia and lung damage. Additionally, Tizoxanide (TIZ), the primary metabolite of NTZ, has been identified as a facilitator of NMRAL1 dimerization. This finding potentially sheds light on the underlying mechanism contributing to TIZ's role in augmenting the sensitivity of the IFN-ß pathway. These results indicate the promising potential of NTZ as a repurposed therapeutic agent for Porcine Reproductive and Respiratory Syndrome (PRRS). Additionally, they provide valuable insights into the antiviral mechanisms underlying NTZ's effectiveness.


Assuntos
Antivirais , Ensaios de Triagem em Larga Escala , Nitrocompostos , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Tiazóis , Animais , Vírus da Síndrome Respiratória e Reprodutiva Suína/efeitos dos fármacos , Nitrocompostos/farmacologia , Suínos , Antivirais/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Síndrome Respiratória e Reprodutiva Suína/tratamento farmacológico , Síndrome Respiratória e Reprodutiva Suína/virologia , Tiazóis/farmacologia , Replicação Viral/efeitos dos fármacos , Linhagem Celular , Viremia/tratamento farmacológico , Viremia/virologia
4.
PLoS One ; 19(6): e0305641, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38885222

RESUMO

HIV can be successfully suppressed to undetectable levels by antiretroviral therapy (ART) in most people with HIV (PWH). However, a small proportion continues to have persistent low-level viremia (LLV) during ART. A presumed source of LLV is production or replication from viral reservoirs, which are maintained in the presence of ART. It is unknown whether the oral cavity can be considered an HIV reservoir. As periodontal inflammation is a common problem in PWH, we hypothesize that periodontal inflammation in the oral cavity activates (latently) infected cells and thus might be associated with LLV. We included 11 individuals with HIV LLV, and compared HIV-RNA levels in saliva and plasma at baseline and at week 24 after switch of ART. We compared the LLV-group at baseline with 11 age-matched controls with suppressed viremia. To investigate the severity of periodontitis we used Periodontal Inflamed Surface Areas (PISA) by measuring probing depth, gingival recession, bleeding on probing and clinical attachment level. Severity of periodontitis was classified according to the CDC-AAP case definition. Additional insights in periodontal inflammation were obtained by comparing immune activation markers and the presence of periodontal pathogens. In four individuals of the LLV group, residual levels of HIV-RNA were detected in saliva at baseline (N = 1) or at week 24 (N = 2) or both (N = 1). Of the four individuals with LLV, three had residual levels of HIV-RNA in saliva. All 22 individuals had moderate to severe periodontitis. PISA was not significantly different between cases with LLV and controls. Similarly, periodontal pathogens were frequently observed in both groups. Total activated HLA-DR+CD38+ CD4+ cells and CD8+ cells were significantly higher in the LLV group than in the control group (p = <0.01). No immune markers were associated with LLV. In conclusion, periodontal inflammation is an unlikely driver of HIV LLV compared to HIV suppressed individuals.


Assuntos
Infecções por HIV , Periodontite , Saliva , Viremia , Humanos , Viremia/virologia , Viremia/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Masculino , Periodontite/virologia , Periodontite/imunologia , Feminino , Adulto , Saliva/virologia , Pessoa de Meia-Idade , RNA Viral/sangue , HIV-1 , Carga Viral , Inflamação/virologia , Estudos de Casos e Controles
5.
Nat Commun ; 15(1): 5093, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877003

RESUMO

The capacity of HIV-1 to replicate during optimal antiretroviral therapy (ART) is challenging to assess directly. To gain greater sensitivity to detect evolution on ART, we used a nonhuman primate (NHP) model providing precise control over the level of pre-ART evolution and more comprehensive analyses than are possible with clinical samples. We infected 21 rhesus macaques (RMs) with the barcoded virus SIVmac239M and initiated ART early to minimize baseline genetic diversity. RMs were treated for 285-1200 days. We used several tests of molecular evolution to compare 1352 near-full-length (nFL) SIV DNA single genome sequences from PBMCs, lymph nodes, and spleen obtained near the time of ART initiation and those present after long-term ART, none of which showed significant changes to the SIV DNA population during ART in any animal. To investigate the possibility of ongoing replication in unsampled putative tissue sanctuaries during ART, we discontinued treatment in four animals and confirmed that none of the 336 nFL SIV RNA sequences obtained from rebound plasma viremia showed evidence of evolution. The rigorous nature of our analyses reinforced the emerging consensus of a lack of appreciable ongoing replication on effective ART and validates the relevance of this NHP model for cure studies.


Assuntos
Antirretrovirais , Macaca mulatta , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Replicação Viral , Animais , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Vírus da Imunodeficiência Símia/fisiologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Replicação Viral/efeitos dos fármacos , Antirretrovirais/uso terapêutico , Evolução Molecular , RNA Viral/genética , Carga Viral/efeitos dos fármacos , Viremia/tratamento farmacológico , Viremia/virologia , DNA Viral/genética , Masculino
6.
Sci Rep ; 14(1): 13815, 2024 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877168

RESUMO

This study was aimed to investigate the frequency of PiCV recombination, the kinetics of PiCV viremia and shedding and the correlation between viral replication and host immune response in young pigeons subclinically infected with various PiCV variants and kept under conditions mimicking the OLR system. Fifteen racing pigeons originating from five breeding facilities were housed together for six weeks. Blood and cloacal swab samples were collected from birds every seven days to recover complete PiCV genomes and determine PiCV genetic diversity and recombination dynamics, as well as to assess virus shedding rate, level of viremia, expression of selected genes and level of anti-PiCV antibodies. Three hundred and eighty-eight complete PiCV genomes were obtained and thirteen genotypes were distinguished. Twenty-five recombination events were detected. Recombinants emerged during the first three weeks of the experiment which was consistent with the peak level of viremia and viral shedding. A further decrease in viremia and shedding partially corresponded with IFN-γ and MX1 gene expression and antibody dynamics. Considering the role of OLR pigeon rearing system in spreading infectious agents and allowing their recombination, it would be reasonable to reflect on the relevance of pigeon racing from both an animal welfare and epidemiological perspective.


Assuntos
Doenças das Aves , Infecções por Circoviridae , Circovirus , Columbidae , Eliminação de Partículas Virais , Animais , Columbidae/virologia , Circovirus/genética , Circovirus/imunologia , Infecções por Circoviridae/veterinária , Infecções por Circoviridae/virologia , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/imunologia , Doenças das Aves/virologia , Doenças das Aves/epidemiologia , Doenças das Aves/imunologia , Viremia/epidemiologia , Viremia/virologia , Viremia/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Genoma Viral , Recombinação Genética , Genótipo , Replicação Viral , Filogenia
7.
Exp Clin Transplant ; 22(3): 185-188, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38695587

RESUMO

OBJECTIVES: Before the advent of direct-acting antiviral therapy for hepatitis C virus, a large proportion of kidneys from donors with hepatitis C viremia were discarded. Hepatitis C virus is now amenable to effective treatment with excellent seronegativity rates. In this study, we review the outcomes of hepatitis C viremic kidneys transplanted into hepatitis C-naive recipients. MATERIALS AND METHODS: In this retrospective observational study, we examined 6 deceased donor kidneys with hepatitis C viremia that were transplanted into hepatitis C-naive recipients between March 2020 and April 2021 at a single center. Because of health insurance constraints, patients were treated for hepatitis C virus with glecaprevir/pibrentasvir for 8 weeks following seroconversion posttransplant. Primary outcome measured was viral seroconversion; secondary outcomes included graft function, posttransplant complications, and all-cause mortality. RESULTS: On average, patients seroconverted 6 days (range, 4-10 d) after transplant and began treatment 26 days (range, 15-37 d) after seroconversion. An 8-week course of antiviral treatment was successful in preventing acute hepatitis C virus infection in all patients. Posttransplant median creatinine was 1.96 mg/dL (range, 1-4.55 mg/dL), whereas median estimated glomerular filtration rate was 41.33 mL/min/1.73 m2 (range, 17-85 mL/min/1.73 m2). Patient survival rate was 66.7%, and death-censored graft survival rate was 100%. Two patients died from unrelated reasons: 1 from acute respiratory failure secondary to SARS-CoV-2 infection and 1 from posttransplant lymphoproliferative disorder. Two patients developed allograft rejection posttransplant (1 developed antibody mediated rejection, 1 developed borderline T-cell-mediated cellular rejection). Other major complications included neutropenia, fungal rash, SARS-CoV-2 infection, cytomegalovirus, BK virus, and Epstein-Barr virus reactivation. CONCLUSIONS: Use of hepatitis C-viremic donor kidneys for transplant is a safe option and has great potential to increase the kidney donor pool, as long as high index of suspicion is maintained for allograft rejection and opportunistic infections.


Assuntos
Antivirais , Benzimidazóis , Seleção do Doador , Hepatite C , Transplante de Rim , Pirrolidinas , Quinoxalinas , Viremia , Humanos , Transplante de Rim/efeitos adversos , Transplante de Rim/mortalidade , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Antivirais/uso terapêutico , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Resultado do Tratamento , Viremia/diagnóstico , Viremia/virologia , Adulto , Fatores de Tempo , Fatores de Risco , Doadores de Tecidos , Combinação de Medicamentos , Sobrevivência de Enxerto , Idoso , Serviços de Saúde Rural , Soroconversão
8.
Exp Clin Transplant ; 22(4): 267-269, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38742316

RESUMO

OBJECTIVES: BK virus is a major cause of chronic renal allograft failure.Transplant ureteral stent use has been reported as a risk factorfor BK virus infection. Recently, the use of a new type of ureteral stent (Magnetic Black Star) was reported in kidney transplant recipients. The aim ofthis preliminary report was to compare BK virus viremia and viruria occurrence depending on the type of double-J stent (standard versus Magnetic Black Star). MATERIALS AND METHODS: We included all kidney transplants performed in our center from January to December 2022. Each case had double-J stent placement. Indwelling stents were either a 6- or 7-Fr standard double-J stent or a 6-Fr Magnetic Black Star double-J stent. The type of double-J stent was chosen according to the surgeon's preference. A standard BK virus screening protocol was followed during the study period, which consisted of routine polymerase chain reaction examination of plasma and urine samples during monthly follow-ups. RESULTS: We assessed 120 patients without missing data: 92 patients received standard double-J stents and 28 patients received Magnetic Black Star stents. Patients were mostly male in the standard group (70.7%) versus the Magnetic Black Star group (42.9%) (P = .01). ABO- and HLA-incompatible transplant rates were similar in both groups. BK viremia occurrence and BK viruria occurrence were similar between groups at 1 month, 3 months, and 6 months. CONCLUSIONS: This preliminary study showed no differences concerning BKvirus infection depending on the type of double-J stents used during kidney transplant.


Assuntos
Vírus BK , Transplante de Rim , Infecções por Polyomavirus , Desenho de Prótese , Stents , Infecções Tumorais por Vírus , Viremia , Humanos , Transplante de Rim/efeitos adversos , Vírus BK/patogenicidade , Vírus BK/imunologia , Masculino , Viremia/diagnóstico , Viremia/virologia , Feminino , Pessoa de Meia-Idade , Infecções por Polyomavirus/virologia , Infecções por Polyomavirus/diagnóstico , Infecções por Polyomavirus/imunologia , Infecções por Polyomavirus/urina , Fatores de Risco , Resultado do Tratamento , Adulto , Infecções Tumorais por Vírus/virologia , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/urina , Fatores de Tempo , Dados Preliminares , Estudos Retrospectivos
9.
Clin Transplant ; 38(5): e15329, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38722085

RESUMO

BACKGROUND: Immunosuppression reduction for BK polyoma virus (BKV) must be balanced against risk of adverse alloimmune outcomes. We sought to characterize risk of alloimmune events after BKV within context of HLA-DR/DQ molecular mismatch (mMM) risk score. METHODS: This single-center study evaluated 460 kidney transplant patients on tacrolimus-mycophenolate-prednisone from 2010-2021. BKV status was classified at 6-months post-transplant as "BKV" or "no BKV" in landmark analysis. Primary outcome was T-cell mediated rejection (TCMR). Secondary outcomes included all-cause graft failure (ACGF), death-censored graft failure (DCGF), de novo donor specific antibody (dnDSA), and antibody-mediated rejection (ABMR). Predictors of outcomes were assessed in Cox proportional hazards models including BKV status and alloimmune risk defined by recipient age and molecular mismatch (RAMM) groups. RESULTS: At 6-months post-transplant, 72 patients had BKV and 388 had no BKV. TCMR occurred in 86 recipients, including 27.8% with BKV and 17% with no BKV (p = .05). TCMR risk was increased in recipients with BKV (HR 1.90, (95% CI 1.14, 3.17); p = .01) and high vs. low-risk RAMM group risk (HR 2.26 (95% CI 1.02, 4.98); p = .02) in multivariable analyses; but not HLA serological MM in sensitivity analysis. Recipients with BKV experienced increased dnDSA in univariable analysis, and there was no association with ABMR, DCGF, or ACGF. CONCLUSIONS: Recipients with BKV had increased risk of TCMR independent of induction immunosuppression and conventional alloimmune risk measures. Recipients with high-risk RAMM experienced increased TCMR risk. Future studies on optimizing immunosuppression for BKV should explore nuanced risk stratification and may consider novel measures of alloimmune risk.


Assuntos
Vírus BK , Rejeição de Enxerto , Sobrevivência de Enxerto , Testes de Função Renal , Transplante de Rim , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Viremia , Humanos , Transplante de Rim/efeitos adversos , Vírus BK/imunologia , Vírus BK/isolamento & purificação , Feminino , Masculino , Infecções por Polyomavirus/imunologia , Infecções por Polyomavirus/virologia , Infecções por Polyomavirus/complicações , Pessoa de Meia-Idade , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/imunologia , Seguimentos , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/virologia , Viremia/imunologia , Viremia/virologia , Prognóstico , Fatores de Risco , Taxa de Filtração Glomerular , Adulto , Complicações Pós-Operatórias , Imunossupressores/uso terapêutico , Imunossupressores/efeitos adversos , Estudos Retrospectivos , Falência Renal Crônica/cirurgia , Falência Renal Crônica/imunologia , Nefropatias/virologia , Nefropatias/imunologia , Nefropatias/cirurgia , Transplantados
10.
Clin Transplant ; 38(5): e15325, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38716770

RESUMO

BACKGROUND/AIMS: Direct-acting antiviral (DAA) therapy has revolutionized solid organ transplantation by providing an opportunity to utilize organs from HCV-viremic donors. Though transplantation of HCV-viremic donor organs into aviremic recipients is safe in the short term, midterm data on survival and post-transplant complications is lacking. We provide a midterm assessment of complications of lung transplantation (LT) up to 2 years post-transplant, including patient and graft survival between HCV-viremic transplantation (D+) and HCV-aviremic transplantation (D-). METHODS: This is a retrospective cohort study including 500 patients from 2018 to 2022 who underwent LT at our quaternary care institution. Outcomes of patients receiving D+ grafts were compared to those receiving D- grafts. Recipients of HCV antibody+ but PCR- grafts were treated as D- recipients. RESULTS: We identified 470 D- and 30 D+ patients meeting inclusion criteria. Crude mortality did not differ between groups (p = .43). Patient survival at years 1 and 2 did not differ between D+ and D- patients (p = .89, p = .87, respectively), and graft survival at years 1 and 2 did not differ between the two groups (p = .90, p = .88, respectively). No extrahepatic manifestations or fibrosing cholestatic hepatitis (FCH) occurred among D+ recipients. D+ and D- patients had similar rates of post-transplant chronic lung allograft rejection (CLAD) (p = 6.7% vs. 12.8%, p = .3), acute cellular rejection (60.0% vs. 58.0%, p = .8) and antibody-mediated rejection (16.7% vs. 14.2%, p = .7). CONCLUSION: There is no difference in midterm patient or graft survival between D+ and D-LT. No extrahepatic manifestations of HCV occurred. No differences in any type of rejection including CLAD were observed, though follow-up for CLAD was limited. These results provide additional support for the use of HCV-viremic organs in selected recipients in LT.


Assuntos
Rejeição de Enxerto , Sobrevivência de Enxerto , Hepacivirus , Hepatite C , Transplante de Pulmão , Complicações Pós-Operatórias , Viremia , Humanos , Transplante de Pulmão/efeitos adversos , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Seguimentos , Prognóstico , Hepatite C/cirurgia , Hepatite C/virologia , Hepacivirus/isolamento & purificação , Viremia/virologia , Viremia/etiologia , Taxa de Sobrevida , Rejeição de Enxerto/etiologia , Fatores de Risco , Doadores de Tecidos/provisão & distribuição , Adulto , Antivirais/uso terapêutico , Transplantados
12.
Am J Transplant ; 24(6): 1057-1069, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38307417

RESUMO

Although cytomegalovirus (CMV) viremia/DNAemia has been associated with reduced survival after lung transplantation, its association with chronic lung allograft dysfunction (CLAD) and its phenotypes is unclear. We hypothesized that, in a modern era of CMV prophylaxis, CMV DNAemia would still remain associated with death, but also represent a risk factor for CLAD and specifically restrictive allograft syndrome (RAS)/mixed phenotype. This was a single-center retrospective cohort study of all consecutive adult, first, bilateral-/single-lung transplants done between 2010-2016, consisting of 668 patients. Risks for death/retransplantation, CLAD, or RAS/mixed, were assessed by adjusted cause-specific Cox proportional-hazards models. CMV viral load (VL) was primarily modeled as a categorical variable: undetectable, detectable to 999, 1000 to 9999, and ≥10 000 IU/mL. In multivariable models, CMV VL was significantly associated with death/retransplantation (≥10 000 IU/mL: HR = 2.65 [1.78-3.94]; P < .01), but was not associated with CLAD, whereas CMV serostatus mismatch was (D+R-: HR = 2.04 [1.30-3.21]; P < .01). CMV VL was not associated with RAS/mixed in univariable analysis. Secondary analyses with a 7-level categorical or 4-level ordinal CMV VL confirmed similar results. In conclusion, CMV DNAemia is a significant risk factor for death/retransplantation, but not for CLAD or RAS/mixed. CMV serostatus mismatch may have an impact on CLAD through a pathway independent of DNAemia.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Rejeição de Enxerto , Sobrevivência de Enxerto , Transplante de Pulmão , Complicações Pós-Operatórias , Viremia , Humanos , Transplante de Pulmão/efeitos adversos , Infecções por Citomegalovirus/virologia , Infecções por Citomegalovirus/epidemiologia , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Viremia/virologia , Viremia/epidemiologia , Citomegalovirus/isolamento & purificação , Fatores de Risco , Seguimentos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/virologia , Prognóstico , Complicações Pós-Operatórias/virologia , Complicações Pós-Operatórias/epidemiologia , Adulto , Carga Viral , Taxa de Sobrevida , Transplantados/estatística & dados numéricos
13.
J Infect Dis ; 229(6): 1770-1780, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38128541

RESUMO

BACKGROUND: A better understanding of the dynamics of human immunodeficiency virus (HIV) reservoirs in CD4+ T cells of people with HIV (PWH) receiving antiretroviral therapy (ART) is crucial for developing therapies to eradicate the virus. METHODS: We conducted a study involving 28 aviremic PWH receiving ART with high and low levels of HIV DNA. We analyzed immunologic and virologic parameters and their association with the HIV reservoir size. RESULTS: The frequency of CD4+ T cells carrying HIV DNA was associated with higher pre-ART plasma viremia, lower pre-ART CD4+ T-cell counts, and lower pre-ART CD4/CD8 ratios. During ART, the High group maintained elevated levels of intact HIV proviral DNA, cell-associated HIV RNA, and inducible virion-associated HIV RNA. HIV sequence analysis showed no evidence for preferential accumulation of defective proviruses nor higher frequencies of clonal expansion in the High versus Low group. Phenotypic and functional T-cell analyses did not show enhanced immune-mediated virologic control in the Low versus High group. Of considerable interest, pre-ART innate immunity was significantly higher in the Low versus High group. CONCLUSIONS: Our data suggest that innate immunity at the time of ART initiation may play an important role in modulating the dynamics and persistence of viral reservoirs in PWH.


Assuntos
Linfócitos T CD4-Positivos , DNA Viral , Infecções por HIV , Carga Viral , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Infecções por HIV/imunologia , Masculino , DNA Viral/sangue , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Feminino , Adulto , Pessoa de Meia-Idade , HIV-1/genética , RNA Viral/sangue , Provírus/genética , Antirretrovirais/uso terapêutico , Relação CD4-CD8 , Contagem de Linfócito CD4 , Viremia/tratamento farmacológico , Viremia/imunologia , Viremia/virologia , Fármacos Anti-HIV/uso terapêutico
14.
J Virol ; 97(11): e0109423, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37874153

RESUMO

IMPORTANCE: Despite the advent of highly active anti-retroviral therapy, people are still dying from HIV-related causes, many of whom are children, and a protective vaccine or cure is needed to end the HIV pandemic. Understanding the nature and activation states of immune cell subsets during infection will provide insights into the immunologic milieu associated with viremia suppression that can be harnessed via therapeutic strategies to achieve a functional cure, but these are understudied in pediatric subjects. We evaluated humoral and adaptive host immunity associated with suppression of viremia in rhesus macaques infected soon after birth with a pathogenic SHIV. The results from our study provide insights into the immune cell subsets and functions associated with viremia control in young macaques that may translate to pediatric subjects for the design of future anti-viral strategies in HIV-1-infected infants and children and contribute to an understudied area of HIV-1 pathogenesis in pediatric subjects.


Assuntos
Animais Recém-Nascidos , Modelos Animais de Doenças , Infecções por HIV , Macaca mulatta , Síndrome de Imunodeficiência Adquirida dos Símios , Viremia , Animais , Criança , Humanos , Animais Recém-Nascidos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Macaca mulatta/imunologia , Macaca mulatta/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/fisiologia , Viremia/imunologia , Viremia/virologia , HIV/imunologia , HIV/fisiologia
15.
J Virol ; 97(4): e0181222, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36971565

RESUMO

The lack of robust immunocompetent animal models for hepatitis C virus (HCV) impedes vaccine development and studies of immune responses. Norway rat hepacivirus (NrHV) infection in rats shares HCV-defining characteristics, including hepatotropism, chronicity, immune responses, and aspects of liver pathology. To exploit genetic variants and research tools, we previously adapted NrHV to prolonged infection in laboratory mice. Through intrahepatic RNA inoculation of molecular clones of the identified variants, we here characterized four mutations in the envelope proteins responsible for mouse adaptation, including one disrupting a glycosylation site. These mutations led to high-titer viremia, similar to that observed in rats. In 4-week-old mice, infection was cleared after around 5 weeks compared to 2 to 3 weeks for nonadapted virus. In contrast, the mutations led to persistent but attenuated infection in rats, and they partially reverted, accompanied by an increase in viremia. Attenuated infection in rat but not mouse hepatoma cells demonstrated that the characterized mutations were indeed mouse adaptive rather than generally adaptive across species and that species determinants and not immune interactions were responsible for attenuation in rats. Unlike persistent NrHV infection in rats, acute resolving infection in mice was not associated with the development of neutralizing antibodies. Finally, infection of scavenger receptor B-I (SR-BI) knockout mice suggested that adaptation to mouse SR-BI was not a primary function of the identified mutations. Rather, the virus may have adapted to lower dependency on SR-BI, thereby potentially surpassing species-specific differences. In conclusion, we identified specific determinants of NrHV mouse adaptation, suggesting species-specific interactions during entry. IMPORTANCE A prophylactic vaccine is required to achieve the World Health Organization's objective for hepatitis C virus elimination as a serious public health threat. However, the lack of robust immunocompetent animal models supporting hepatitis C virus infection impedes vaccine development as well as studies of immune responses and viral evasion. Hepatitis C virus-related hepaciviruses were discovered in a number of animal species and provide useful surrogate infection models. Norway rat hepacivirus is of particular interest, as it enables studies in rats, an immunocompetent and widely used small laboratory animal model. Its adaptation to robust infection also in laboratory mice provides access to a broader set of mouse genetic lines and comprehensive research tools. The presented mouse-adapted infectious clones will be of utility for reverse genetic studies, and the Norway rat hepacivirus mouse model will facilitate studies of hepacivirus infection for in-depth characterization of virus-host interactions, immune responses, and liver pathology.


Assuntos
Adaptação Fisiológica , Hepacivirus , Hepatite C , Adaptação Fisiológica/genética , Adaptação Fisiológica/imunologia , Hepacivirus/genética , Hepacivirus/imunologia , Viremia/imunologia , Viremia/virologia , Mutação , Animais , Camundongos , Ratos , Hepatite C/imunologia , Hepatite C/fisiopatologia , Hepatite C/virologia , Modelos Animais de Doenças , Hospedeiro Imunocomprometido , Linhagem Celular , Antígenos CD36/genética , Antígenos CD36/imunologia
16.
PLoS One ; 18(1): e0278862, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662705

RESUMO

BACKGROUND: Monkeypox virus has recently emerged from endemic foci in Africa and, since October 20, 2022, more than 73,000 human infections have been reported by the CDC from over 100 countries that historically have not reported monkeypox cases. The detection of virus in skin lesions, blood, semen, and saliva of infected patients with monkeypox infections raises the potential for disease transmission via routes that have not been previously documented, including by blood and plasma transfusions. Methods for protecting the blood supply against the threats of newly emerging disease agents exist and include Pathogen Reduction Technologies (PRT) which utilize photochemical treatment processes to inactivate pathogens in blood while preserving the integrity of plasma and cellular components. Such methods have been employed broadly for over 15 years, but effectiveness of these methods under routine use conditions against monkeypox virus has not been reported. STUDY DESIGN AND METHODS: Monkeypox virus (strain USA_2003) was used to inoculate plasma and whole blood units that were then treated with riboflavin and UV light (Mirasol Pathogen Reduction Technology System, Terumo BCT, Lakewood, CO). The infectious titers of monkeypox virus in the samples before and after riboflavin + UV treatment were determined by plaque assay on Vero cells. RESULTS: The levels of spiked virus present in whole blood and plasma samples exceeded 103 infectious particles per dose, corresponding to greater than 105 DNA copies per mL. Treatment of whole blood and plasma units under standard operating procedures for the Mirasol PRT System resulted in complete inactivation of infectivity to the limits of detection. This is equivalent to a reduction of ≥ 2.86 +/- 0.73 log10 pfu/mL of infectivity in whole blood and ≥ 3.47 +/-0.19 log10 pfu/mL of infectivity in plasma under standard operating conditions for those products. CONCLUSION: Based on this data and corresponding studies on infectivity in patients with monkeypox infections, use of Mirasol PRT would be expected to significantly reduce the risk of transfusion transmission of monkeypox.


Assuntos
Monkeypox virus , Mpox , Viremia , Animais , Humanos , Plaquetas , Chlorocebus aethiops , Mpox/sangue , Mpox/complicações , Mpox/virologia , Riboflavina/farmacologia , Raios Ultravioleta , Células Vero , Viremia/virologia
17.
BMC Vet Res ; 18(1): 364, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36192746

RESUMO

BACKGROUND: Selecting American mink (Neovison vison) for tolerance to Aleutian mink disease virus (AMDV) has gained popularity in recent years, but data on the outcomes of this activity are scant. The objectives of this study were to determine the long-term changes in viremia, seroconversion and survival in infected mink. Mink were inoculated intranasally with a local isolate of Aleutian mink disease virus (AMDV) over 4 years (n = 1742). The animals had been selected for tolerance to AMDV for more than 20 years (TG100) or were from herds free of AMDV (TG0). The progenies of TG100 and TG0, and their crosses with 25, 50 and 75% tolerance ancestry were also used. Blood samples were collected from each mink up to 14 times until 1211 days post-inoculation (dpi) and were tested for viremia by PCR and for anti-AMDV antibodies by counter-immunoelectrophoresis (CIEP). Viremia and CIEP status were not considered when selecting replacements. Low-performing animals were pelted and the presence of antibodies in their blood and antibody titer were measured by CIEP, and viremia and viral DNA in seven organs (n = 936) were tested by PCR. RESULTS: The peak incidences of viremia (66.7%) and seropositivity (93.5%) were at 35 dpi. The incidence of viremia decreased over time while the incidence of seroconversion increased. The least-squares means of the incidence of PCR positive of lymph node (0.743) and spleen (0.656) were significantly greater than those of bone marrow, liver, kidneys, lungs and small intestine (0.194 to 0.342). Differences in tolerant ancestry were significant for every trait measured. Incidences of viremia over time, terminal viremia, seropositivity over time, AMDV DNA in organs and antibody titer were highest in the susceptible groups (TG0 or TG25) and lowest in the tolerant groups (TG100 or TG75). CONCLUSION: Previous history of selection for tolerance resulted in mink with reduced viral replication and antibody titer. Viremia had a negative effect and antibody production had a positive effect on survival and productivity.


Assuntos
Vírus da Doença Aleutiana do Vison , Doença Aleutiana do Vison , Anticorpos Antivirais , Formação de Anticorpos , Vison , Viremia , Doença Aleutiana do Vison/sangue , Doença Aleutiana do Vison/imunologia , Doença Aleutiana do Vison/mortalidade , Doença Aleutiana do Vison/virologia , Vírus da Doença Aleutiana do Vison/genética , Vírus da Doença Aleutiana do Vison/imunologia , Vírus da Doença Aleutiana do Vison/isolamento & purificação , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , DNA Viral/análise , Feminino , Masculino , Vison/sangue , Vison/imunologia , Vison/virologia , Taxa de Sobrevida , Viremia/sangue , Viremia/imunologia , Viremia/veterinária , Viremia/virologia , Replicação Viral
18.
J Virol ; 96(16): e0058822, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35916523

RESUMO

Co-infection with hepatitis B (HBV) and human immunodeficiency virus (HIV) increases overall and liver-related mortality. In order to identify interactions between these two viruses in vivo, full-length HIV proviruses were sequenced from a cohort of HIV-HBV co-infected participants and from a cohort of HIV mono-infected participants recruited from Bangkok, Thailand, both before the initiation of antiretroviral therapy (ART) and after at least 2 years of ART. The co-infected individuals were found to have higher levels of genetically-intact HIV proviruses than did mono-infected individuals pre-therapy. In these co-infected individuals, higher levels of genetically-intact HIV proviruses or proviral genetic-diversity were also associated with higher levels of sCD14 and CXCL10, suggesting that immune activation is linked to more genetically-intact HIV proviruses. Three years of ART decreased the overall level of HIV proviruses, with fewer genetically-intact proviruses being identified in co-infected versus mono-infected individuals. However, ART increased the frequency of certain genetic defects within proviruses and the expansion of identical HIV sequences. IMPORTANCE With the increased availability and efficacy of ART, co-morbidities are now one of the leading causes of death in HIV-positive individuals. One of these co-morbidities is co-infection with HBV. However, co-infections are still relatively understudied, especially in countries where such co-infections are endemic. Furthermore, these countries have different subtypes of HIV circulating than the commonly studied HIV subtype B. We believe that our study serves this understudied niche and provides a novel approach to investigating the impact of HBV co-infection on HIV infection. We examine co-infection at the molecular level in order to investigate indirect associations between the two viruses through their interactions with the immune system. We demonstrate that increased immune inflammation and activation in HBV co-infected individuals is associated with higher HIV viremia and an increased number of genetically-intact HIV proviruses in peripheral blood cells. This leads us to hypothesize that inflammation could be a driver in the increased mortality rate of HIV-HBV co-infected individuals.


Assuntos
Coinfecção , Infecções por HIV , Hepatite B , Inflamação/virologia , Coinfecção/patologia , Coinfecção/virologia , DNA Viral/genética , Infecções por HIV/complicações , Infecções por HIV/patologia , Infecções por HIV/virologia , Hepatite B/complicações , Hepatite B/patologia , Hepatite B/virologia , Vírus da Hepatite B/fisiologia , Humanos , Provírus/genética , Tailândia/epidemiologia , Viremia/virologia
19.
Nature ; 606(7913): 375-381, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35650437

RESUMO

Antiretroviral therapy is highly effective in suppressing human immunodeficiency virus (HIV)1. However, eradication of the virus in individuals with HIV has not been possible to date2. Given that HIV suppression requires life-long antiretroviral therapy, predominantly on a daily basis, there is a need to develop clinically effective alternatives that use long-acting antiviral agents to inhibit viral replication3. Here we report the results of a two-component clinical trial involving the passive transfer of two HIV-specific broadly neutralizing monoclonal antibodies, 3BNC117 and 10-1074. The first component was a randomized, double-blind, placebo-controlled trial that enrolled participants who initiated antiretroviral therapy during the acute/early phase of HIV infection. The second component was an open-label single-arm trial that enrolled individuals with viraemic control who were naive to antiretroviral therapy. Up to 8 infusions of 3BNC117 and 10-1074, administered over a period of 24 weeks, were well tolerated without any serious adverse events related to the infusions. Compared with the placebo, the combination broadly neutralizing monoclonal antibodies maintained complete suppression of plasma viraemia (for up to 43 weeks) after analytical treatment interruption, provided that no antibody-resistant HIV was detected at the baseline in the study participants. Similarly, potent HIV suppression was seen in the antiretroviral-therapy-naive study participants with viraemia carrying sensitive virus at the baseline. Our data demonstrate that combination therapy with broadly neutralizing monoclonal antibodies can provide long-term virological suppression without antiretroviral therapy in individuals with HIV, and our experience offers guidance for future clinical trials involving next-generation antibodies with long half-lives.


Assuntos
Fármacos Anti-HIV , Anticorpos Neutralizantes , Anticorpos Anti-HIV , Infecções por HIV , HIV-1 , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/imunologia , Fármacos Anti-HIV/uso terapêutico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/efeitos adversos , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Amplamente Neutralizantes/administração & dosagem , Anticorpos Amplamente Neutralizantes/efeitos adversos , Anticorpos Amplamente Neutralizantes/imunologia , Anticorpos Amplamente Neutralizantes/uso terapêutico , Método Duplo-Cego , Anticorpos Anti-HIV/administração & dosagem , Anticorpos Anti-HIV/efeitos adversos , Anticorpos Anti-HIV/imunologia , Anticorpos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/imunologia , HIV-1/isolamento & purificação , Humanos , Carga Viral/efeitos dos fármacos , Viremia/tratamento farmacológico , Viremia/imunologia , Viremia/virologia
20.
Ren Fail ; 44(1): 434-449, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35260039

RESUMO

Kidney transplantation is the treatment of choice in end-stage renal disease. The main issue which does not allow to utilize it fully is the number of organs available for transplant. Introduction of highly effective oral direct-acting antivirals (DAAs) to the treatment of chronic hepatitis C virus infection (HCV) enabled transplantation of HCV viremic organs to naive recipients. Despite an increasing number of reports on the satisfying effects of using HCV viremic organs, including kidneys, they are more often rejected than those from HCV negative donors. The main reason is the presence of HCV viremia and not the quality of the organ. The current state of knowledge points to the fact that a kidney transplant from an HCV nucleic acid testing positive (NAT+) donor to naive recipients is an effective and safe solution to the problem of the insufficient number of organs available for transplantation. It does not, however, allow to draw conclusions as to the long-term consequence of such an approach. This review analyzes the possibilities and limitations of the usage of HCV NAT + donor organs. Abbreviations: DAA: direct-acting antivirals; HCV: hepatitis C virus; NAT: nucleic acid testing; OPTN: Organ Procurement and Transplantation Network; KDIGO: Kidney Disease: Improving Global Outcomes; Ab: antigen; eGFR: estimated glomerular filtration rate; D: donor; R: recipient; CMV: cytomegalovirus; HBV: hepatitis B virus; UNOS: United Network for Organ Sharing; PHS: Public Health Service; EBR/GZR: elbasvir/grazoprevir; SVR: sustained virologic response; RAS: resistance-associated substitutions; SOF: soforbuvir; GLE/PIB: glecaprevir/pibrentasvir; ACR: acute cellular rejection; AR: acute rejection; DSA: donor-specific antibodies; KTR: kidney transplant recipients; AASLD: American Association for the Study of Liver Disease; IDSA: Infectious Diseases Society of America; PPI: proton pump inhibitors; CKD: chronic kidney disease; GN: glomerulonephritis; KAS: The Kidney Allocation system.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/transmissão , Transplante de Rim , Rim/virologia , Rejeição de Enxerto/virologia , Humanos , Obtenção de Tecidos e Órgãos , Viremia/virologia
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