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1.
J Med Virol ; 96(6): e29742, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38874263

RESUMO

Polyomaviruses BK (BKPyV) and JC (JCPyV), belonging to the Polyomaviridae, are responsible for human pathologies. In kidney transplant recipients, BKPyV replication can lead to irreversible nephron damage whereas JCPyV replication remains asymptomatic. Concomitant replication is rare and potential competition between the infections has been described. The aim of this retrospective case-control study was to describe the molecular epidemiology and risk factors associated with BKPyV and JCPyV replication in a cohort of kidney transplant recipients. In total, 655 urine samples from 460 patients were tested for BKPyV and JCPyV DNA. Positive samples were submitted to strain genotyping. Demographic and clinical characteristics were also compared. Isolated JCPyV and BKPyV was found in 16.5% and 23.3% of patients, respectively; co-replication was rare (3.9%). BKPyV strains Ib-2, Ib-1, and IVc-2 were the most prevalent. JCPyV strains mostly belonged to genotypes 4 and 1B. During follow-up, JCPyV shedding significantly reduced the risk of BKPyV DNAuria, with an odds ratio of 0.57 (95% confidence interval: 0.35-0.99), and was associated with better prognosis than BKPyV replication, based on the estimated glomerular filtration rate. Molecular epidemiology of BKPyV and JCPyV strains in our region was similar to previous studies. This study suggests that JCPyV is benign and appears to limit damaging BKPyV replication. JCPyV DNAuria screening could thus be a useful strategy to predict BKPyV-related outcomes.


Assuntos
Vírus BK , Genótipo , Vírus JC , Transplante de Rim , Epidemiologia Molecular , Infecções por Polyomavirus , Humanos , Vírus BK/genética , Vírus BK/isolamento & purificação , Infecções por Polyomavirus/epidemiologia , Infecções por Polyomavirus/virologia , Infecções por Polyomavirus/urina , Transplante de Rim/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Vírus JC/genética , Vírus JC/isolamento & purificação , Estudos de Casos e Controles , Adulto , Eliminação de Partículas Virais , Idoso , Transplantados/estatística & dados numéricos , Infecções Tumorais por Vírus/epidemiologia , Infecções Tumorais por Vírus/virologia , Infecções Tumorais por Vírus/urina , DNA Viral/urina , DNA Viral/genética , Aloenxertos/virologia
2.
Pathogens ; 13(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38668270

RESUMO

BACKGROUND/OBJECTIVES: In the absence of an effective antiviral treatment for BK polyomavirus (BKPyV), a better understanding of the epidemiology and time course of BKPyV replication after kidney transplantation is needed to limit the virus's impact on the graft outcome. METHODS: In a 7-year study, we screened more than 430 kidney transplant recipients and analyzed the time course and virological characteristics of BKPyV replication. RESULTS: Urinary viral replication was observed in 116 (27%) of the 430 patients, and 90 of the 116 (78%) had viral DNAemia. Thirty-eight patients (8.8%) were presumed to have nephropathy (DNAemia > 4 log10 copies/mL). Of the patients with BKPyV replication, 48%, 60%, 71%, and 80% were first found to be positive one, two, three, and four months post-transplantation. The initial viral load in the urine was below 7 log10 copies/mL in 100% of the patients with viral replication first detected before the first month, and this proportion was 57% when viral replication was first detected after the first month. When the BKPyV replication was first detected in a urine sample at month 3 or later, 81.5% of patients had concomitant BKPyV DNAemia. The predominant viral subtype was Ib2 (60%), and there was no apparent relationship between the subtype and the time course of BKPyV replication. CONCLUSIONS: Urinary BKPyV replication occurs early after renal transplantation and in most patients will increase to a level requiring therapeutic intervention. Close monitoring for BKPyV in the early post-transplantation period would enable the pre-emptive adjustment of the immunosuppression regimen.

3.
J Clin Virol ; 171: 105656, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38412681

RESUMO

BK Polyomavirus is of particular concern for kidney transplant recipients, due to their immunosuppression. This problem is exacerbated by the high effectiveness of antirejection therapies, which also compromise the organism's ability to fight viral infections. The long-term risk is loss of graft function through BKPyV-associated nephropathy (BKPyVAN). The assessment of host immunity and its link to the control of viral infections is a major challenge. In terms of humoral immunity, researchers have highlighted the prognostic value of the pre-transplantation anti-BKPyV immunoglobulin G titer. However, humoral immunity alone does not guarantee viral clearance, and the correlation between the humoral response and the time course of the infection remains weak. In contrast, cellular immunity variables appear to be more closely associated with viral clearance, given that the cellular immune response to the kidney transplant is the main target of immunosuppressive treatments in recipients. However, the assessment of the cellular immune response to BK Polyomavirus is complex, and many details still need to be characterized. Here, we review the current state of knowledge about BKPyV cellular immunity, as well as the difficulties that may be encountered in studying it in kidney transplant recipient. This is an essential area of research for optimizing the management of transplant recipients and minimizing the risks associated with insidious BKPyV disease.


Assuntos
Vírus BK , Nefropatias , Transplante de Rim , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Humanos , Transplante de Rim/efeitos adversos , Vírus BK/fisiologia , Transplantados
4.
Front Med (Lausanne) ; 10: 1281625, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38093979

RESUMO

Background: BK polyomavirus replication leads to progressive tubulointerstitial nephritis and ureteral stenosis, with a considerable risk of subsequent graft failure in kidney transplant recipients. Since specific antiviral therapies are lacking, new tools are required to enhance the biological monitoring of the infection. Viral microRNAs are promising new biomarkers, but the performance of RT-qPCR methods limits the clinical application and the validation of a standard method for quantification. Methods: We compared TaqMan microRNA Assays and TaqMan Advanced miRNA Assays for bkv-miR-B1-3p and bkv-miR-B1-5p quantification in synthetic microRNA templates and in 44 urine samples belonging to 14 consecutive kidney transplant recipients with BK polyomavirus replication from Amiens University Medical Center in a 1-year span. Results: Cycle threshold values were constantly higher with TaqMan Advanced MicroRNA Assays. TaqMan microRNA Assays showed better performance in predicting the good prognosis of BK polyomavirus nephropathy. Conclusion: Overall, TaqMan MicroRNA Assays appeared to be a more sensitive and accurate RT-qPCR method than TaqMan Advanced MicroRNA Assays to quantify bkv-miR-B1-3p and bkv-miR-B1-5p BKPyV miRNAs in patients' urine samples.

5.
Transpl Infect Dis ; 25(2): e14012, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36748721

RESUMO

BACKGROUND: Among kidney transplant recipients (KTR) with BK virus associated nephropathy (BKVN), BKV genotypes' evolution and anti-BKV humoral response are not well established. We aim to analyze BKV replication and genetic evolution following transplantation, and characterize concomitant anti-BKV-VP1 humoral response. METHODS: We retrospectively analyzed 32 cases of biopsy-proven BKVN. Stored plasma and kidney biopsies were tested for BKV viral load, and VP1 sequencing performed on positive samples. BKV-VP1 genotype-specific neutralizing antibodies (NAbs) titers were determined at transplantation and BKVN. RESULTS: At the time of BKVN diagnosis, BKV viral load was 8.2 log10 IU/106 cells and 5.4 log10 IU/mL in kidney and plasma, respectively. VP1 sequencing identified the same BKV-subtype in both compartments in 31/32 cases. At the time of transplantation, 8/20 (40%) of biopsies tested positive for BKV detection, whereas concomitant BKV viremia was negative. VP1 sequencing identified a different subtype compared to BKVN in 5/6 of these samples. This was confirmed following transplantation: 8 patients had a BKV+ biopsy before BKV viremia, and VP1 sequencing identified a different subtype compared to BKVN in all of them. After the onset of BKV viremia and prior to BKVN diagnosis, the BKV subtype in BKV+ plasma and kidney biopsy was the same as the one isolated at BKVN. BKV-VP1 NAbs titers were significantly higher at the time of BKVN compared to transplantation (p = .0031), with similar titers across genotypes. CONCLUSION: Altogether, our data suggest that among some KTR with BKVN, the BKV genotype from the donor may not be responsible for BKVN pathogenesis.


Assuntos
Vírus BK , Nefropatias , Transplante de Rim , Nefrite Intersticial , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Humanos , Transplante de Rim/efeitos adversos , Viremia/complicações , Estudos Retrospectivos , Transplantados , Genótipo
6.
Int J Mol Sci ; 23(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35806242

RESUMO

BACKGROUND: Bkv-miR-B1-5p is a viral micro-RNA (miRNA) specifically produced during BK polyomavirus (BKPyV) replication. Recent studies have suggested using bkv-miR-B1-5p as a biomarker to monitor viral infection and predict complications in kidney transplant patients. To identify the technical limitations of this miRNA quantification in biological samples, knowledge of its stability and distribution in the extracellular compartment is necessary. Moreover, a proof of concept for using bkv-miR-B1-5p as a biomarker of active replication in chronic infection is still missing in the published literature. METHODS: The stability of bkv-miR-B1-5p was evaluated in samples derived from cell cultures and in urine from BKPyV-infected kidney transplant recipients. The miRNA was quantified in different fractions of the extracellular compartment, including exosomes, and protein binding was evaluated. Finally, we developed an in vitro model for chronic culture of BKPyV clinical isolates to observe changes in the bkv-miR-B1-5p level during persistent infections. RESULTS: Bkv-miR-B1-5p is a stable biomarker in samples from humans and in vitro experiments. Marginally associated with the exosomes, most of the circulating bkv-miR-B1-5p is bound to proteins, especially Ago2, so the miRNA quantification does not require specific exosome isolation. The bkv-miR-B1-5p level is predictable of viral infectivity, which makes it a potential specific biomarker of active BKPyV replication after kidney transplantation.


Assuntos
Vírus BK , Nefropatias , Transplante de Rim , MicroRNAs , Infecções por Polyomavirus , Vírus BK/genética , Biomarcadores , Humanos , Nefropatias/etiologia , Transplante de Rim/efeitos adversos , MicroRNAs/genética , Infecções por Polyomavirus/genética , RNA Viral/genética , Replicação Viral
7.
Nephrol Dial Transplant ; 37(4): 781-788, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-34586413

RESUMO

OBJECTIVES: BK polyomavirus-associated nephropathy is a troublesome disease caused by BK polyomavirus (BKPyV) infection in immunocompromised renal graft recipients. There are no effective treatments available, making immunosuppression reduction the only management option. Thus, pre-graft predictive BKPyV replication markers are needed for identification of patients at high risk of viraemia. METHODS: We conducted a retrospective study to assess the correlation between pre-transplantation BKPyV serostatus and post-transplantation incidence of BKPyV infection. Sera from 329 recipients and 222 matched donors were tested for anti-BKPyV antibodies against BKPyV serotypes I and IV by using a virus-like particle-based immunoglobulin G enzyme-linked immunosorbent assay, and BKPyV DNA load was monitored for at least 1 year post-transplantation. RESULTS: Eighty recipients were viruric and 59 recipients were viraemic post-transplantation. In the post-transplantation period, the probability of developing viraemia for serotype I increased from 4.3% for the D-/R+ group to 12.1% for the D+/R+ group, climbing to 37.5% for the D+/R- group (P < 0.05). When calculating recipient mean titres for serotypes I and IV, we observed a clear difference in the proportions of viraemia, decreasing from 50% for mean titres <400 to 13.5% for titres ≥400 (P < 0.001), as well as a higher proportion of presumptive nephropathy (50% versus 23.1%, respectively; P < 0.05). In univariate analysis, this parameter had an odds ratio of 6.41 for the risk of developing post-transplantation BKPyV viraemia (95% confidence interval 3.16-13.07; P < 0.0001). CONCLUSIONS: Determination of both donor and recipient BKPyV seropositivity before transplantation and antibody titre measurements may serve as a predictive tool to manage clinical BKPyV infection by identification of patients at high risk.


Assuntos
Vírus BK , Transplante de Rim , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Feminino , Humanos , Transplante de Rim/efeitos adversos , Masculino , Infecções por Polyomavirus/diagnóstico , Infecções por Polyomavirus/epidemiologia , Infecções por Polyomavirus/etiologia , Estudos Retrospectivos , Transplantados , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/epidemiologia , Infecções Tumorais por Vírus/etiologia , Viremia/diagnóstico , Viremia/epidemiologia , Viremia/etiologia
8.
Viruses ; 13(2)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33672313

RESUMO

BACKGROUND: Kidney transplant recipients (KTRs) are exposed to a high risk of BK polyomavirus (BKPyV) replication, which in turn may lead to graft loss. Although the microRNAs (miRNAs) bkv-miR-B1-3p and bkv-miR-B1-5p are produced during the viral cycle, their putative value as markers of viral replication has yet to be established. In KTRs, the clinical relevance of the changes over time in BKPyV miRNA levels has not been determined. METHODS: In a retrospective study, we analyzed 186 urine samples and 120 plasma samples collected from 67 KTRs during the first year post-transplantation. Using a reproducible, standardized, quantitative RT-PCR assay, we measured the levels of bkv-miR-B1-3p and bkv-miR-B1-5p (relative to the BKPyV DNA load). RESULTS: Detection of the two miRNAs had low diagnostic value for identifying patients with DNAemia or for predicting DNAuria during follow-up. Seven of the 14 KTRs with a sustained BKPyV infection within the first year post-transplantation showed a progressive reduction in the DNA load and then a rapid disappearance of the miRNAs. DNA and miRNA loads were stable in the other seven KTRs. CONCLUSIONS: After the DNA-based diagnosis of BKPyV infection in KTRs, bkv-miR-B1-3p and bkv-miR-B1-5p levels in the urine might be valuable markers for viral replication monitoring and thus might help physicians to avoid an excessive reduction in the immunosuppressive regimen.


Assuntos
Vírus BK/fisiologia , MicroRNAs/genética , Infecções por Polyomavirus/virologia , Complicações Pós-Operatórias/virologia , RNA Viral/genética , Adulto , Idoso , Vírus BK/genética , Biomarcadores/sangue , Biomarcadores/urina , Feminino , Humanos , Transplante de Rim/efeitos adversos , Transplante de Rim/estatística & dados numéricos , Masculino , MicroRNAs/sangue , MicroRNAs/urina , Pessoa de Meia-Idade , Infecções por Polyomavirus/sangue , Infecções por Polyomavirus/etiologia , Infecções por Polyomavirus/urina , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/urina , RNA Viral/sangue , RNA Viral/urina , Estudos Retrospectivos , Transplantados/estatística & dados numéricos , Carga Viral , Replicação Viral
9.
New Microbiol ; 44(1): 59-61, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33582823

RESUMO

In the context of a second wave of SARS-CoV-2 transmission, the use of saliva sampling has become an issue of real importance. SARS-CoV-2 RNA screening was performed on nasopharyngeal and saliva swabs collected from 501 individuals from residential homes for the elderly. The saliva samples were collected at the same time as the nasopharyngeal samples. Nasopharyngeal samples yielded positive results for 26 individuals, only two of whom also tested positive with saliva swabs. In this context, saliva collected by swabbing the fluid is not an ideal sample.


Assuntos
COVID-19 , SARS-CoV-2 , Idoso , Humanos , Programas de Rastreamento , RNA Viral/genética , Saliva
10.
Viruses ; 12(10)2020 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-32993049

RESUMO

Extracellular vesicles have recently emerged as a novel mode of viral transmission exploited by naked viruses to exit host cells through a nonlytic pathway. Extracellular vesicles can allow multiple viral particles to collectively traffic in and out of cells, thus enhancing the viral fitness and diversifying the transmission routes while evading the immune system. This has been shown for several RNA viruses that belong to the Picornaviridae, Hepeviridae, Reoviridae, and Caliciviridae families; however, recent studies also demonstrated that the BK and JC viruses, two DNA viruses that belong to the Polyomaviridae family, use a similar strategy. In this review, we provide an update on recent advances in understanding the mechanisms used by naked viruses to hijack extracellular vesicles, and we discuss the implications for the biology of polyomaviruses.


Assuntos
Vesículas Extracelulares/virologia , Evasão da Resposta Imune/fisiologia , Infecções por Polyomavirus/transmissão , Polyomavirus/metabolismo , Infecções Tumorais por Vírus/transmissão , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Endocitose/fisiologia , Humanos , Polyomavirus/imunologia , Infecções Tumorais por Vírus/virologia , Internalização do Vírus , Replicação Viral/fisiologia
11.
Viruses ; 12(8)2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32784805

RESUMO

Reactivation of BK polyomavirus (BKPyV) infection is frequently increasing in transplant recipients treated with potent immunosuppressants and highlights the importance of immune system components in controlling viral reactivation. However, the immune response to BKPyV in general and the role of antiviral cytokines in infection control in particular are poorly understood. Here, we investigated the efficacy of interferons (IFN) alpha, lambda and gamma with regard to the BKPyV multiplication in Vero cells. Treatment with IFN-gamma inhibited the expression of the viral protein VP1 in a dose-dependent manner and decreased the expression of early and late viral transcripts. Viral inhibition by IFN-gamma was confirmed in human cells (Caki-1 cells and renal proximal tubular epithelial cells). One of the IFN-stimulated genes most strongly induced by IFN-gamma was the coding for the enzyme indoleamine 2,3 dioxygenase (IDO), which is known to limit viral replication and regulates the host immune system. The antiviral activity induced by IFN-gamma could be reversed by the addition of an IDO inhibitor, indicating that IDO has a specific role in anti-BKPyV activity. A better understanding of the action mechanism of these IFN-gamma-induced antiviral proteins might facilitate the development of novel therapeutic strategies.


Assuntos
Vírus BK/efeitos dos fármacos , Vírus BK/fisiologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Interferon gama/farmacologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Chlorocebus aethiops , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Interferon-alfa/imunologia , Interferon gama/imunologia , Interferons/imunologia , Interferons/farmacologia , Túbulos Renais Proximais , Transdução de Sinais , Células Vero , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos
12.
J Virol ; 94(6)2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-31896595

RESUMO

Most people are asymptomatic carriers of the BK polyomavirus (BKPyV), but the mechanisms of persistence and immune evasion remain poorly understood. Furthermore, BKPyV is responsible for nephropathies in kidney transplant recipients. Unfortunately, the sole therapeutic option is to modulate immunosuppression, which increases the risk of transplant rejection. Using iodixanol density gradients, we observed that Vero and renal proximal tubular epithelial infected cells release two populations of infectious particles, one of which cosediments with extracellular vesicles (EVs). Electron microscopy confirmed that a single vesicle could traffic tens of viral particles. In contrast to naked virions, the EV-associated particles (eBKPyVs) were not able to agglutinate red blood cells and did not use cell surface sialylated glycans as an attachment factor, demonstrating that different entry pathways were involved for each type of infectious particle. However, we also observed that naked BKPyV and eBKPyV were equally sensitive to neutralization by the serum of a seropositive patient or commercially available polyvalent immunoglobulin preparations, which occurred at a postattachment step, after endocytosis. In conclusion, our work shows a new mechanism that likely plays a critical role during the primary infection and in the persistence, but also the reactivation, of BKPyV.IMPORTANCE Reactivation of BKPyV is responsible for nephropathies in kidney transplant recipients, which frequently lead to graft loss. The mechanisms of persistence and immune evasion used by this virus remain poorly understood, and a therapeutic option for transplant patients is still lacking. Here, we show that BKPyV can be released into EVs, enabling viral particles to infect cells using an alternative entry pathway. This provides a new view of BKPyV pathogenesis. Even though we did not find any decreased sensitivity to neutralizing antibodies when comparing EV-associated particles and naked virions, our study also raises important questions about developing prevention strategies based on the induction or administration of neutralizing antibodies. Deciphering this new release pathway could enable the identification of therapeutic targets to prevent BKPyV nephropathies. It could also lead to a better understanding of the pathophysiology of other polyomaviruses that are associated with human diseases.


Assuntos
Vírus BK/metabolismo , Vesículas Extracelulares/metabolismo , Infecções por Polyomavirus/transmissão , Animais , Vírus BK/genética , Vírus BK/patogenicidade , Chlorocebus aethiops , Vesículas Extracelulares/genética , Vesículas Extracelulares/virologia , Infecções por Polyomavirus/genética , Infecções por Polyomavirus/metabolismo , Células Vero
13.
Viruses ; 11(10)2019 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615131

RESUMO

The immunosuppression required for graft tolerance in kidney transplant patients can trigger latent BK polyomavirus (BKPyV) reactivation, and the infection can progress to nephropathy and graft rejection. It has been suggested that pre-transplantation BKPyV serostatus in donors and recipients is a predictive marker for post-transplantation BKPyV replication. The fact that research laboratories have used many different assay techniques to determine BKPyV serostatus complicates these data analysis. Even studies based on the same technique differed in their standard controls choice, the antigenic structure type used for detection, and the cut-off for seropositivity. Here, we review the different BKPyV VP1 antigens types used for detection and consider the various BKPyV serostatus assay techniques' advantages and disadvantages. Lastly, we highlight the obstacles in the implementation of a consensual BKPyV serologic assay in clinics (e.g., the guidelines absence in this field).


Assuntos
Vírus BK/isolamento & purificação , Transplante de Rim , Infecções Tumorais por Vírus/diagnóstico , Viremia/prevenção & controle , Vírus BK/imunologia , DNA Viral , Rejeição de Enxerto/prevenção & controle , Rejeição de Enxerto/virologia , Humanos , Terapia de Imunossupressão , Estudos Retrospectivos , Testes Sorológicos , Transplantados , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/prevenção & controle
15.
J Clin Virol ; 116: 4-6, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30986626

RESUMO

BACKGROUND: Assessment of the intensity of immunosuppression in transplant recipients to estimate the risk of rejection and infection is not entirely satisfactory at the present time. Determination of Torque teno virus (TTV) viral load appears to be a promising tool in this setting. OBJECTIVES: We evaluated the level of replication and kinetics of TTV during the first three months after kidney transplantation compared to BK virus replication. RESULTS: In a retrospective cohort of 116 renal transplant recipients, TTV viral load gradually increased during the first three months post-transplantation with no significant difference or discriminatory threshold between patients with and without BK virus replication. However, the level of TTV replication appeared to be indirectly related to the risk of BK virus replication, particularly according to the induction treatment used (antithymocyte globulin: ATG or basiliximab). Among patients receiving ATG, those receiving cyclosporine had significantly lower TTV viral loads (p < 0.01) with threefold lower reactivation of BKPyV (13 vs 37%) 3 months post-transplantation. Similarly, among the women in our cohort, TTV viral load was significantly higher in women receiving ATG (6.58 ± 1.57 versus 4.62 ± 2.0 log10 copies/mL for basiliximab: p < 0.01), also with threefold higher BKPyV reactivation frequencies (40 vs 13,3%). CONCLUSION: The multiparametric variation of TTV viral load does not appear to be individually appropriate for the early detection or monitoring of possible post-transplant BKPyV virus reactivation in renal transplant recipients.


Assuntos
Vírus BK/fisiologia , Transplante de Rim/efeitos adversos , Torque teno virus/fisiologia , Adulto , Vírus BK/efeitos dos fármacos , Vírus BK/genética , Biomarcadores/sangue , DNA Viral/sangue , Feminino , Humanos , Terapia de Imunossupressão , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Torque teno virus/efeitos dos fármacos , Torque teno virus/genética , Carga Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
16.
Rev Med Virol ; 29(2): e2033, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30614131

RESUMO

HCV has been associated with a pro-inflammatory state, which predisposes to hepatocellular carcinoma (HCC). However, the different molecular mechanisms underlying the effect of HCV infection on HCC progression remain unclear. Although HCV infection illustrates the potential role of host genetics in the outcome of infectious diseases, there is no clear overview of some single nucleotide polymorphisms (SNPs) influencing spontaneous or treatment-induced HCV eradication. We studied the possible role of HCV infection in the processes of HCC initiation and performed a systematic analysis using data mining approaches to identify host polymorphisms associated with treatment response and HCC development using topological analysis of protein-proteins interactions (PPI) networks. On the basis of our analysis performed, we identified key hub proteins related to HCV-treatment response infection and to HCC development. Host genetic polymorphisms, such as inosine triphosphatase (ITPA), interferon, lambda 3 (IFNL3), Q5 interferon, lambda 4 (IFNL4), toll-like receptors (TLRs) and interferon-stimulated gene 15 (ISG-15), were identified as key genes for treatment prediction and HCC evolution. By comparing unique genes for HCV-treatment response and genes particular to HCV-HCC development, we found a common PPI network that may participate in more extensive signalling processes during anti-HCV treatment, which can play important roles in modulating the immune response to the occurrence of HCC. Data mining is an effective tool for identifying potential regulatory pathways involved in treatment response and HCC development. Our study may contribute to a better understanding of HCV immunopathogenesis and highlights the complex role of host genetics in HCV clearance.


Assuntos
Carcinoma Hepatocelular/fisiopatologia , Resistência à Doença , Predisposição Genética para Doença , Hepatite C Crônica/complicações , Hepatite C Crônica/imunologia , Interações Hospedeiro-Patógeno , Mapas de Interação de Proteínas , Carcinoma Hepatocelular/genética , Mineração de Dados , Hepatite C Crônica/genética , Humanos , Neoplasias Hepáticas/fisiopatologia , Polimorfismo Genético
17.
Genes Immun ; 20(7): 599-605, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30177859

RESUMO

The major histocompatibility complex class I polypeptide-related sequence A (MICA) glycoprotein mediates the activation of the natural killer group 2D receptor (NKG2D) expressed on NK and CD8+ T cells. A methionine or valine at position 129 in exon 3 results in strong (MICA129 met) or weak (MICA129 val) binding to NKG2D. The MICA A5.1 allele causes a premature stop codon. Various NKG2D polymorphisms are associated with low (NKC3 C/C and NKC4 C/C) or high (NKC3 G/G and NKC4 T/T) levels of NK cell cytotoxic activity. In 162 patients with spondyloarthritis (115 with ankylosing spondyloarthritis, 46 with psoriatic arthritis and 1 with reactive arthritis) compared to 124 healthy controls, MICA-129 with methionine allele was more frequent in patients with spondyloarthritis (odds ratio (OR) (95% confidence interval) = 4.84 (2.75‒8.67)), whereas MICA-129 val/val, MICA A5.1 and NKC3 C/C variants were less frequent (OR = 0.20 (0.11‒0.37), 0.15 (0.06‒0.36) and 0.24 (0.13‒0.44), respectively). After adjustment for HLA-B*27 status, only NKC3 C/C remained linked to spondyloarthritis (adjusted OR = 0.14 (0.06‒0.33)). Homozygosity for MICA A5.1 is linked to ankylosing spondyloarthritis, and NKC3 C/C and MICA-129 val/val to psoriatic arthritis. MICA and NKC3 polymorphisms (related to a low NK cell cytotoxic activity) constituted a genetic association with spondyloarthritis.


Assuntos
Antígenos de Histocompatibilidade Classe I/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Espondilartrite/genética , Adolescente , Adulto , Idoso , Alelos , Linfócitos T CD8-Positivos/metabolismo , Estudos de Casos e Controles , Criança , Feminino , Frequência do Gene/genética , Genes MHC Classe I , Predisposição Genética para Doença/genética , Variação Genética/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Células Matadoras Naturais/metabolismo , Masculino , Pessoa de Meia-Idade , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Razão de Chances , Polimorfismo Genético/genética , Estudos Retrospectivos , Fatores de Risco , Espondilartrite/metabolismo , População Branca/genética
18.
J Clin Virol ; 109: 6-12, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30343190

RESUMO

In the last 20 years, the management of BK polyomavirus (BKPyV) reactivation in kidney transplant patients has become a true challenge for the transplant community. The only treatment option is based on the early identification of at-risk patients. The number of reported risk factors for BKPyV reactivation has increased markedly in the literature last years, although they are sometimes in an unclear or contradictory manner. Our purpose is to provide a systematic review and meta-analysis of risk factors for BKPyV viremia and nephropathy described in multivariate analyses. The PubMed database was searched for prospective or prospectively-based observational studies on risk factors for BKPyV viremia and/or nephropathy. Our qualitative assessment of risk factors was based on the odds ratios and hazard ratios calculated in multivariate regression analyses. Of the 241 publications screened, 34 were included in the qualitative analysis. In all, 144 and 19 distinct factors were analyzed for BKPyV viremia and for BKPyV nephropathy, respectively. Our evaluation highlighted eight risk factors for BKPyV viremia: a tacrolimus regimen, a deceased donor, a male recipient, a history of previous transplant, age at transplantation, ureteral stent use, delayed graft function, and acute rejection episodes increased the risk of BKV viremia to varying extents. Tacrolimus and acute rejection episodes were also associated with a higher incidence of BKPyV nephropathy. BKPyV reactivation is a serious complication after renal transplantation. With a view to combating this problem, existing data should be published in full, and new prospective international multicenter studies should be performed.


Assuntos
Vírus BK/fisiologia , Nefropatias/epidemiologia , Transplante de Rim/efeitos adversos , Viremia/epidemiologia , Humanos , Nefropatias/complicações , Análise Multivariada , Infecções por Polyomavirus/epidemiologia , Fatores de Risco , Infecções Tumorais por Vírus/epidemiologia , Viremia/complicações , Ativação Viral
19.
J Clin Virol ; 102: 27-31, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29477833

RESUMO

BACKGROUND: Acute respiratory infections are a principal cause of illness and mortality especially in young children worldwide. OBJECTIVES: To study the epidemiology and seasonality of viral respiratory infections in hospitalized children (under the age of 16) between September 2012 and August 2016. STUDY DESIGN: Nasopharyngeal swabs or aspirates were collected from 3199 symptomatic patients and then screened with a routine multiplex PCR assay. RESULTS: Respiratory viruses were detected for 1624 (50.8%) of the 3199 children in the study population. Of these, 210 (13.3%) were positive for two viruses, 28 (1.7%) were positive for three, and 3 (0.2%) were positive for four. The viral profile varied with age. Some viruses were significantly more frequent in children under the age of 1 month (such as human respiratory syncytial virus (p < 0.0001)), whereas others were significantly more frequent in children over that age (such as influenza viruses (p < 0.0001) and adenoviruses (p = .0006)). The distribution of viruses is variable over the year depending on the species. However, the atmospheric temperature was rarely found to be a limiting factor in the circulation of respiratory viruses. CONCLUSIONS: our results constitute a detailed description of the distribution of respiratory viruses among hospitalized children over four consecutive years. Our data notably highlight the persistence of non-enveloped viruses and some enveloped viruses throughout the year-regardless of temperature variations.


Assuntos
Hospitalização , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Estações do Ano , Vírus/isolamento & purificação , Doença Aguda , Adolescente , Fatores Etários , Criança , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/virologia , França/epidemiologia , Humanos , Lactente , Recém-Nascido , Reação em Cadeia da Polimerase Multiplex , Estudos Retrospectivos , Vírus/classificação
20.
Diagn Microbiol Infect Dis ; 90(2): 96-101, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29198371

RESUMO

This study compared the performance of 3 automated immunoassays, Architect® (Abbott), Immulite® (Siemens) and Liaison® (Diasorin), for Epstein-Barr virus (EBV) serology. Ninety-one serum samples collected in Amiens University Hospital were analyzed for the presence of Viral Capsid Antigen (VCA) IgG and IgM and Epstein-Barr Nuclear Antigen (EBNA) IgG. The agreement between the 3 assays was calculated for each marker individually and for determination of the EBV profile, based on interpretation of the combination of these 3 EBV markers. Although similar results were obtained with Architect® and Liaison®, several discordant results were observed with Immulite®, particularly for EBNA IgG. A large number of EBNA IgG-positive results were observed, which interfered with interpretation of the EBV profile. In contrast, Immulite® performed similarly to the 2 other assays for detection of VCA IgM.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/imunologia , Imunoensaio/métodos , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/isolamento & purificação , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Estudos Retrospectivos , Sensibilidade e Especificidade , Virologia
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