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1.
Transfusion ; 61(1): 144-158, 2021 01.
Article de Anglais | MEDLINE | ID: mdl-33089891

RÉSUMÉ

BACKGROUND: Epstein-Barr virus (EBV) is carried in the blood of most adults, and transfusion-related infections have been reported. EBV is particularly deleterious in immunosuppressed transplant patients. The aim was to determine if EBV transmission occurred through leukodepleted blood product transfusion in pediatric recipients of hematopoietic stem cell transplants (HSCT). STUDY DESIGN AND METHODS: This prospective Canadian multi-center cohort study includes 156 allogeneic HSCT pediatric recipients. The association between EBV and transfusion was analyzed using Cox regressions. EBV infection, defined by a PCR+ test in the blood of seronegative recipients of an EBV-negative graft, was monitored in order to correlate the recipient EBV strain with that of the blood donors. EBV genotypes were determined by PCR amplification followed by DNA sequencing at two loci (EBNA3b and LMP1). RESULTS: No statistically significant associations were found between transfusions and EBV. One case of post-transplant EBV infection was identified among the 21 EBV-seronegative recipients receiving an EBV-negative graft. A total of 22 blood donors were retraced to determine whether the recipient's EBV strain matched that of a donor. One donor strain showed 100% sequence homology at the EBNA3b locus, but differed by one or two point mutations and by a 132-bp deletion at the LMP1 locus. The blood donor in question was alone among the 22 donors to show amplifiable virus in plasma. Blood from this donor readily produced an immortalized lymphoblastoid cell line in culture. CONCLUSION: While considered a rare event, EBV transmission through transfusion may occur in the context of severe immunosuppression.


Sujet(s)
Infections à virus Epstein-Barr/transmission , Transplantation de cellules souches hématopoïétiques/effets indésirables , Herpèsvirus humain de type 4/génétique , Réaction transfusionnelle/virologie , Receveurs de transplantation/statistiques et données numériques , Donneurs de sang/statistiques et données numériques , Transfusion sanguine/méthodes , Transfusion sanguine/statistiques et données numériques , Canada/épidémiologie , Enfant , Enfant d'âge préscolaire , Études de cohortes , Infections à virus Epstein-Barr/diagnostic , Infections à virus Epstein-Barr/virologie , Antigènes nucléaires du virus d'Epstein-Barr/génétique , Femelle , Génotype , Herpèsvirus humain de type 4/immunologie , Humains , Immunosuppression thérapeutique/effets indésirables , Mâle , Études prospectives , Protéines de la matrice virale/génétique
2.
Clin Microbiol Rev ; 33(4)2020 09 16.
Article de Anglais | MEDLINE | ID: mdl-32847820

RÉSUMÉ

Viral primary infections and reactivations are common complications in patients after solid organ transplantation (SOT) and hematopoietic stem cell transplantation (HSCT) and are associated with high morbidity and mortality. Among these patients, viral infections are frequently associated with viremia. Beyond the usual well-known viruses that are part of the routine clinical management of transplant recipients, numerous other viral signatures or genomes can be identified in the blood of these patients. The identification of novel viral species and variants by metagenomic next-generation sequencing has opened up a new field of investigation and new paradigms. Thus, there is a need to thoroughly describe the state of knowledge in this field with a review of all viral infections that should be scrutinized in high-risk populations. Here, we review the eukaryotic DNA and RNA viruses identified in blood, plasma, or serum samples of pediatric and adult SOT/HSCT recipients and the prevalence of their detection, with a particular focus on recently identified viruses and those for which their potential association with disease remains to be investigated, such as members of the Polyomaviridae, Anelloviridae, Flaviviridae, and Astroviridae families. Current knowledge of the clinical significance of these viral infections with associated viremia among transplant recipients is also discussed. To ensure a comprehensive description in these two populations, individuals described as healthy (mostly blood donors) are considered for comparative purposes. The list of viruses that should be on the clinicians' radar is certainly incomplete and will expand, but the challenge is to identify those of possible clinical significance.


Sujet(s)
Sang/virologie , Transplantation de cellules souches hématopoïétiques/statistiques et données numériques , Receveurs de transplantation/statistiques et données numériques , Transplants/virologie , Virome , Maladies virales/transmission , Infections à cytomégalovirus/transmission , Infections à virus Epstein-Barr/transmission , Transplantation de cellules souches hématopoïétiques/effets indésirables , Humains , Maladies virales/sang
3.
Sci Rep ; 9(1): 9290, 2019 06 26.
Article de Anglais | MEDLINE | ID: mdl-31243321

RÉSUMÉ

Epstein-Barr virus (EBV) is one of the most common human viruses and the cause of pathologies such as infectious mononucleosis (IM) and certain cancers. No vaccine against EBV infection currently exists, but such vaccines are in development. Knowledge of how EBV is transmitted at the population level is critical to the development of target product profiles (TPPs) for such vaccines and future vaccination strategies. We present the first mathematical model of EBV transmission, parameterised using data from England, and use it to compare hypothetical prophylactic vaccines with different characteristics and the impact of vaccinating different age groups. We found that vaccine duration had more impact than vaccine efficacy on modelled EBV and IM prevalence. The age group vaccinated also had an important effect: vaccinating at a younger age led to a greater reduction in seroprevalence but an increase in IM cases associated with delayed infection. Vaccination had impact on cancer incidence only in the long run, because in England most EBV-related cancers arise in later life. Durability of protection should be a key factor to prioritise in EBV vaccine development and included in vaccine TPPs. These findings are timely and important for vaccine developers and policy-makers alike.


Sujet(s)
Infections à virus Epstein-Barr/prévention et contrôle , Infections à virus Epstein-Barr/transmission , Vaccination , Adolescent , Calibrage , Enfant , Enfant d'âge préscolaire , Études transversales , Angleterre/épidémiologie , Infections à virus Epstein-Barr/sang , Herpèsvirus humain de type 4 , Humains , Incidence , Nourrisson , Nouveau-né , Mononucléose infectieuse/prévention et contrôle , Mononucléose infectieuse/virologie , Modèles théoriques , Tumeurs/prévention et contrôle , Tumeurs/virologie , Prévalence , Facteurs de risque , Études séroépidémiologiques , Jeune adulte
4.
Clin Infect Dis ; 68(2): 306-312, 2019 01 07.
Article de Anglais | MEDLINE | ID: mdl-29846551

RÉSUMÉ

Background: A potential source of primary Epstein-Barr virus (EBV) infection for young children is parental oral secretions. If parents who identify with racial/ethnic categories other than white have a higher prevalence of oral EBV DNA, this difference could explain why their children acquire primary EBV infection at an earlier age than white children. Methods: To test this hypothesis, we recruited parents who brought their children <8 years old to routine clinic visits, and tested the parents' oral washes for EBV DNA by real-time polymerase chain reaction. Positive samples were assayed for encapsidated EBV DNA, which is potentially infectious, versus naked EBV DNA, which is not infectious. Results: Overall, 221/800 parents (28%) had EBV DNA in their oral washes. Oral EBV DNA was more prevalent in parents who identified as non-white as compared with white parents (P = .0004), and was more prevalent in male vs female parents (P = .04). The mean quantity of EBV DNA in positive samples was 5000 copies/mL. Encapsidated viral DNA comprised 40.3% of the total EBV DNA found in parental oral secretions. Conclusions: Our data support the hypothesis that parents could be a source of virus for their young children, because 28% of parents had a mean of 5000 EBV copies/mL of oral wash and 40.3% of the EBV DNA was encapsidated. The higher prevalence of EBV DNA in non-white parents could explain why their children acquire EBV at an earlier age than children of white parents.


Sujet(s)
ADN viral/isolement et purification , Infections à virus Epstein-Barr/transmission , Infections à virus Epstein-Barr/virologie , Herpèsvirus humain de type 4/isolement et purification , Salive/virologie , Adolescent , Adulte , Sujet âgé , Enfant d'âge préscolaire , ADN viral/génétique , Femelle , Herpèsvirus humain de type 4/génétique , Humains , Mâle , Adulte d'âge moyen , Parents , Charge virale , Jeune adulte
5.
PLoS One ; 13(11): e0205632, 2018.
Article de Anglais | MEDLINE | ID: mdl-30444879

RÉSUMÉ

Macaque RFHV and LCV are close homologs of human KSHV and EBV, respectively. No experimental model of RFHV has been developed due to the lack of a source of culturable infectious virus. Screening of macaques at the Washington National Primate Research Center detected RFHV in saliva of SIV-infected macaques from previous vaccine studies. A pilot experimental infection of two naïve juvenile pig-tailed macaques was initiated by inoculation of saliva from SIV-infected pig-tailed and cynomolgus macaque donors, which contained high levels of DNA (> 10(6) genomes/ml) of the respective species-specific RFHV strain. Both juvenile recipients developed SIV and RFHV infections with RFHV DNA detected transiently in saliva and/or PBMC around week 16 post-infection. One juvenile macaque was infected with the homologous RFHVMn from whole saliva of a pig-tailed donor, which had been inoculated into the cheek pouch. This animal became immunosuppressed, developing simian AIDS and was euthanized 23 weeks after inoculation. The levels of RFHV DNA in saliva and PBMC remained below the level of detection after week 17, showing no reactivation of the RFHVMn infection during the rapid development of AIDS. The other juvenile macaque was infected with the heterologous RFHVMf from i.v. inoculation of purified virions from saliva of a cynomolgus donor. The juvenile recipient remained immunocompetent, developing high levels of persistent anti-RFHV and -SIV antibodies. After the initial presence of RFHVMf DNA in saliva and PBMC decreased to undetectable levels by week 19, all attempts to reactivate the infection through additional inoculations, experimental infection with purified SRV-2 or SIV, or immunosuppressive treatments with cyclosporine or dexamethasone were unsuccessful. An heterologous LCV transmission was also detected in this recipient, characterized by continual high levels of LCVMf DNA from the cynomolgus donor in both saliva (> 10(6) genomes/ml) and PBMC (> 10(4) genomes/million cells), coupled with high levels of anti-LCV antibodies. The macaque was sacrificed 209 weeks after the initial inoculation. Low levels of LCVMf DNA were detected in salivary glands, tonsils and other lymphoid organs, while RFHVMf DNA was below the level of detection. These results show successful co-transmission of RFHV and LCV from saliva and demonstrate differential lytic activation of the different gammaherpesvirus lineages due to presumed differences in biology and tropism and control by the host immune system. Although this initial pilot transmission study utilized only two macaques, it provides the first evidence for experimental transmission of the macaque homolog of KSHV, setting the stage for larger transmission studies to examine the differential activation of rhadinovirus and lymphocryptovirus infections and the pathological effects of immunosuppression.


Sujet(s)
Herpèsvirus humain de type 4/génétique , Herpèsvirus humain de type 8/génétique , Virus de l'immunodéficience simienne/génétique , Protéines virales/génétique , Animaux , Infections à virus Epstein-Barr/transmission , Infections à virus Epstein-Barr/virologie , Herpèsvirus humain de type 4/pathogénicité , Herpèsvirus humain de type 8/pathogénicité , Humains , Agranulocytes/virologie , Macaca mulatta/virologie , Syndrome d'immunodéficience acquise du singe , Virus de l'immunodéficience simienne/pathogénicité , Washington
6.
J Clin Virol ; 102: 84-92, 2018 05.
Article de Anglais | MEDLINE | ID: mdl-29525635

RÉSUMÉ

Epstein-Barr virus (EBV) infects about 90% of adults worldwide. It is the main cause of infectious mononucleosis, which is observed most frequently in adolescents. The disease can last several weeks and is characterized by lymphocytosis, sore throat, lymphadenopathy, and fatigue. Exposure to oral secretions during deep kissing has been identified as the major source for primary EBV infection in adolescents. Oral secretions are also thought to be the source for younger children through intimate intact or sharing food and eating utensils, although this has not been confirmed. Unlike most acute viral illnesses such as influenza, the incubation period of symptomatic primary EBV infection is unusually long, lasting about six weeks. Diagnosis is typically made by heterophile antibody tests and/or EBV-specific antibody tests. Long-term consequences may result from acquisition of the virus, including nasopharyngeal carcinoma and lymphomas. Nevertheless, there remains a surprising dearth of knowledge regarding the establishment of an immune response to persistent EBV infection, especially during the incubation period. This lack of knowledge has impaired our ability to develop an effective prophylactic EBV vaccine, despite various attempts. Our greatest challenges in EBV research are to develop a prophylactic vaccine and devise treatment strategies for persons already infected with EBV.


Sujet(s)
Infections à virus Epstein-Barr/anatomopathologie , Infections à virus Epstein-Barr/transmission , Herpèsvirus humain de type 4 , Facteurs âges , Infections à virus Epstein-Barr/immunologie , Infections à virus Epstein-Barr/virologie , Herpèsvirus humain de type 4/immunologie , Humains , Période d'incubation de la maladie infectieuse , Modèles biologiques , Facteurs de risque , Vaccins antiviraux
7.
Antiviral Res ; 138: 68-78, 2017 02.
Article de Anglais | MEDLINE | ID: mdl-27939840

RÉSUMÉ

Infection with the oncogenic γ-herpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) cause several severe malignancies in humans. Inhibition of the lytic replication of EBV and KSHV eliminates the reservoir of persistent infection and transmission, consequently preventing the occurrence of diseases from the sources of infection. Antiviral drugs are limited in controlling these viral infectious diseases. Here, we demonstrate that niclosamide, an old anthelmintic drug, inhibits mTOR activation during EBV lytic replication. Consequently, niclosamide effectively suppresses EBV lytic gene expression, viral DNA lytic replication and virion production in EBV-infected lymphoma cells and epithelial cells. Niclosamide exhibits cytotoxicity toward lymphoma cells and induces irreversible cell cycle arrest in lytically EBV-infected cells. The ectopic overexpression of mTOR reverses the inhibition of niclosamide in EBV lytic replication. Similarly, niclosamide inhibits KSHV lytic replication. Thus, we conclude that niclosamide is a promising candidate for chemotherapy against the acute occurrence and transmission of infectious diseases of oncogenic γ-herpesviruses.


Sujet(s)
Réplication de l'ADN/effets des médicaments et des substances chimiques , Herpèsvirus humain de type 4/effets des médicaments et des substances chimiques , Niclosamide/pharmacologie , Sérine-thréonine kinases TOR/métabolisme , Réplication virale/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Cellules épithéliales/virologie , Infections à virus Epstein-Barr/transmission , Infections à virus Epstein-Barr/virologie , Herpèsvirus humain de type 4/physiologie , Humains , Sérine-thréonine kinases TOR/génétique , Protéines virales/génétique , Protéines virales/métabolisme , Virion/effets des médicaments et des substances chimiques , Activation virale/effets des médicaments et des substances chimiques
8.
J Virol ; 91(1)2017 Jan 01.
Article de Anglais | MEDLINE | ID: mdl-27795426
9.
Clin. transl. oncol. (Print) ; 18(2): 206-211, feb. 2016. ilus, graf
Article de Anglais | IBECS | ID: ibc-148226

RÉSUMÉ

Purpose. EBER-1 (a non-coding RNA transcribed by EBV) expression was detected in most of Epstein-Barr virus (EBV)-positive nasopharyngeal carcinoma (NPC) patients. However, the relevance between EBER-1 expression and NPC clinical outcome has not been reported. This study aims to assess the possible correlations of EBER-1 expression and clinical parameters and its potential prognostic predictive ability in NPC patient’s outcomes. Methods. We examined EBER-1 mRNA expression in 301 NPC and 130 non-NPC tissues using in situ hybridization and did statistics. Results. EBER-1 expression was up-regulated in NPC tissues when compared to non-NPC tissues. A receiver operating characteristic analysis revealed that EBER-1 expression could distinguish non-cancerous patients from NPC patients (p < 0.001, sensitivity: 72.5 %, specificity: 83.5 %, AUC = 0.815). A survival analysis revealed that patients with high levels of EBER-1 expression had a significantly good prognosis (Disease-free survival: p = 0.019, overall survival: p = 0.006). Conclusion. These results indicated that EBER-1 expression is a potential prognosis factor of NPC and highly negative correlated with the progress of NPC (AU)


No disponible


Sujet(s)
Humains , Mâle , Femelle , Carcinomes/anatomopathologie , Carcinomes/génétique , Tumeurs du rhinopharynx/métabolisme , Tumeurs du rhinopharynx/anatomopathologie , Infections à virus Epstein-Barr/transmission , Infections à virus Epstein-Barr/virologie , Consentement libre et éclairé/psychologie , Phénotype , Apoptose/génétique , Acide gastrique/métabolisme , Carcinomes/complications , Carcinomes/diagnostic , Tumeurs du rhinopharynx/complications , Tumeurs du rhinopharynx/diagnostic , Infections à virus Epstein-Barr/métabolisme , Infections à virus Epstein-Barr/anatomopathologie , Survie sans rechute , Consentement libre et éclairé/normes , Apoptose/physiologie , Acide gastrique/enzymologie
10.
Indian Pediatr ; 52(11): 946-50, 2015 Nov.
Article de Anglais | MEDLINE | ID: mdl-26615341

RÉSUMÉ

OBJECTIVE: To determine the rate of occurrence and genotypes of Epstein-Barr Virus (EBV) among pediatric renal and liver transplants recipients. DESIGN: Observational study. SETTING: Vision Research Foundation referral center and Institute of Liver Disease and Transplantation, Chennai, India. PARTICIPANTS: 70 pediatric solid organ transplant recipients and 60 voluntary healthy donors. METHODS: Polymerase chain reaction (PCR) for detection and genotyping of EBV were carried out using genes targeting Viral capsid antigen, Nuclear antigen 1, 2 and 3, followed by real time PCR for viral load determination and further confirmed by phylogenetic analysis. RESULTS: EBV was detected in 35 (51.4%) samples (32 liver and 4 renal transplants) with high viral load. Type A was detected in 33 samples, Type B in 2 liver transplant patients, and co-infection in one liver transplant patient who developed Post-transplant Lymphoproliferative Disorder (PTLD). Real time PCR results correlated with conventional PCR. The mean viral load for patients who did not develop PTLD was 50,424 copies/mL. Overall EBV load in patient with PTLD ranged from 1,40,392 copies/mL prior to PTLD diagnosis to 62,124 copies /mL post treatment. CONCLUSION: EBV infection is the high risk factor for PTLD after liver transplantation. PCR targeting of EBV can be applied to diagnose EBV infections and monitor treatment for EBV in pediatric solid organ transplant recipients.


Sujet(s)
Infections à virus Epstein-Barr/virologie , Herpèsvirus humain de type 4/génétique , Transplantation rénale/effets indésirables , Transplantation hépatique/effets indésirables , Transplants/virologie , Adolescent , Adulte , Infections à virus Epstein-Barr/étiologie , Infections à virus Epstein-Barr/transmission , Humains , Inde/épidémiologie , Réaction de polymérisation en chaîne , Receveurs de transplantation/statistiques et données numériques , Jeune adulte
11.
Br J Haematol ; 171(4): 491-500, 2015 Nov.
Article de Anglais | MEDLINE | ID: mdl-26250758

RÉSUMÉ

The post-transplant lymphoproliferative disorders (PTLD) comprise a heterogeneous group of lymphocytic and plasma cell proliferations occurring in recipients of tissue allografts in the setting of immunosuppression. We describe our experience of 120 patients with PTLD seen between 1990 and 2009, one of the largest series reported by a single institution. Post-transplant lymphoproliferative disorders characteristics were analysed with regard to paediatric and adult patients, and with regard to the decade of diagnosis, 1990-1999 (pre-rituximab era) versus 2000-2009 (the rituximab era). We present a new prognostic score using the recursive partitioning model, consisting of the Eastern Cooperative Oncology Group (ECOG) score (0-1 vs. 2-4), age [paediatrics (<16 years old), adults (16-60 years old) and elderly (>60 years old)] and CD20 status (positive vs negative); separating patients into 4 risk categories based on overall survival. Low-risk included paediatric patients with ECOG score of 0-1; intermediate-low-risk included adults aged 16-60 years with an ECOG score of 0-1; intermediate-high-risk included elderly patients with an ECOG score 0-1 or paediatric patients and adults aged 16-60 years with an ECOG score of 2-4 and CD20 positive; high-risk group included patients of any age with an ECOG score of 2-4 and CD20 negative, and elderly patients with an ECOG score of 2-4 with CD20-positive PTLD.


Sujet(s)
Syndromes lymphoprolifératifs/mortalité , Transplantation d'organe , Complications postopératoires/mortalité , Adolescent , Adulte , Sujet âgé , Enfant , Enfant d'âge préscolaire , Association thérapeutique , Infections à virus Epstein-Barr/transmission , Femelle , Humains , Immunosuppresseurs/effets indésirables , Nourrisson , Syndromes lymphoprolifératifs/traitement médicamenteux , Syndromes lymphoprolifératifs/thérapie , Syndromes lymphoprolifératifs/virologie , Mâle , Adulte d'âge moyen , Analyse multifactorielle , Transplantation d'organe/effets indésirables , Complications postopératoires/traitement médicamenteux , Complications postopératoires/virologie , Pronostic , Appréciation des risques , Rituximab/usage thérapeutique , Indice de gravité de la maladie , Jeune adulte
12.
J Infect Dis ; 212(11): 1735-42, 2015 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-25985902

RÉSUMÉ

BACKGROUND: We previously reported that infants in Kenya were infected with Epstein-Barr virus (EBV) at <6 months of age, suggesting that mothers were the likely source of transmissible virus to the infant. In this study, we investigated whether breast milk contained infectious EBV and the role of malaria in EBV shedding in breast milk. METHODS: Breast milk samples were obtained from Kenyan mothers at postpartum weeks 6, 10, 14, and 18 and analyzed for presence of infectious EBV. RESULTS: We found that the prevalence of EBV DNA and the mean EBV load were significantly higher at 6 weeks and decreased through postpartum week 18 (P < .0001). High EBV load in breast milk correlated with mothers who had Plasmodium falciparum malaria at delivery. To determine whether viral DNA was encapsidated, breast milk samples were treated with DNAse before DNA extraction. Sixty percent of samples were DNAse resistant, suggesting that the viral DNA in breast milk was encapsidated. Next, we exposed peripheral blood mononuclear cells to breast milk supernatant, which resulted in the generation of EBV-positive lymphoblastoid cell lines, indicating that the virus in breast milk was infectious. CONCLUSIONS: Our data suggest that breast milk contains infectious EBV and is a potential source of viral transmission to infants living in malaria-endemic regions.


Sujet(s)
Infections à virus Epstein-Barr/transmission , Infections à virus Epstein-Barr/virologie , Herpèsvirus humain de type 4/génétique , Lait humain/virologie , ADN viral/analyse , Infections à virus Epstein-Barr/épidémiologie , Femelle , Humains , Nourrisson , Kenya/épidémiologie , Paludisme , Prévalence , Études prospectives , Charge virale
13.
Vox Sang ; 109(1): 95-7, 2015 Jul.
Article de Anglais | MEDLINE | ID: mdl-25827634

RÉSUMÉ

Adenovirus and Epstein-Barr virus can cause significant morbidity and mortality in paediatric patients post-bone marrow transplant. The source of infection is thought to be either reactivation of latent viruses or primary infection. We have investigated whether transfusion of blood components from viraemic donors could provide a route of primary infection in these patients and sought the prevalence of viraemia in the blood donor population from England. In 32 linked donor/recipient samples and 300 unselected blood donors, we found no evidence to suggest that these infections in paediatric bone marrow transplant recipients had been acquired from transfused blood components.


Sujet(s)
Adenoviridae/génétique , Transplantation de moelle osseuse , ADN viral/analyse , Herpèsvirus humain de type 4/génétique , Adenoviridae/isolement et purification , Infections à Adenoviridae/transmission , Infections à Adenoviridae/virologie , Transfusion de composants du sang , Donneurs de sang , Test ELISA , Infections à virus Epstein-Barr/transmission , Infections à virus Epstein-Barr/virologie , Herpèsvirus humain de type 4/isolement et purification , Humains , Réaction de polymérisation en chaine en temps réel
14.
Transplantation ; 99(6): 1186-91, 2015 Jun.
Article de Anglais | MEDLINE | ID: mdl-25489844

RÉSUMÉ

BACKGROUND: Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections are a significant cause of morbidity and mortality in transplant recipients and are often transmitted from the donor organ. METHODS: In a pilot prospective, randomized, double-blinded, placebo-controlled trial, we studied whether 14 days of pretransplant donor treatment with valganciclovir (valG) versus placebo reduced donor-to-recipient transmission, making posttransplant recipient prophylaxis more effective in reducing EBV and CMV disease. RESULTS: Seventeen D+ R- donor-recipient pairs were enrolled: 7 and 10 donors were randomized to valG and placebo, respectively. At study initiation, no donor had detectable CMV replication, five had EBV replication (two in valG, three in placebo group): EBV replication was undetectable during valG treatment, but resumed on stopping valG. Valganciclovir was tolerated without side effects or leukopenia. All recipients received routine posttransplant viral prophylaxis with valG. For recipients, viremia-free survival time, incidence, range, peak, and duration of CMV and EBV viremia were not significantly different between groups. There was no disease in the valG group but two serious viral diseases occurred in the placebo group (one CMV; one EBV-related posttransplant lymphoproliferative disorder). In the case of posttransplant lymphoproliferative disorder, the EBV DNA from the donor's oral wash and the recipient's lymphoid tissue biopsy had identical latent membrane protein 1 (LMP-1) sequence variations from the reference EBV strain, making it highly probable that the recipient's virus was of donor origin. CONCLUSION: Based on this pilot trial, we recommend an adequately powered study to determine if pretransplant donor treatment with valG can reduce posttransplant CMV and EBV disease with merely routine posttransplant recipient viral prophylaxis.


Sujet(s)
Antiviraux/administration et posologie , Infections à cytomégalovirus/prévention et contrôle , Infections à virus Epstein-Barr/prévention et contrôle , Ganciclovir/analogues et dérivés , Transplantation rénale , Donneur vivant , Adolescent , Adulte , Sujet âgé , Enfant , Enfant d'âge préscolaire , Infections à cytomégalovirus/transmission , Méthode en double aveugle , Infections à virus Epstein-Barr/transmission , Femelle , Ganciclovir/administration et posologie , Humains , Nourrisson , Transplantation rénale/effets indésirables , Transplantation rénale/méthodes , Mâle , Adulte d'âge moyen , Projets pilotes , Études prospectives , Valganciclovir , Virémie/prévention et contrôle , Réplication virale/effets des médicaments et des substances chimiques , Jeune adulte
15.
PLoS One ; 9(12): e114870, 2014.
Article de Anglais | MEDLINE | ID: mdl-25522217

RÉSUMÉ

BACKGROUND: HIV-infected infants in sub-Saharan Africa have rapid disease progression. We hypothesized that co-infection with cytomegalovirus (CMV) or Epstein Barr virus (EBV) increases mortality in HIV-infected infants. METHODS: 257 antiretroviral therapy-naïve HIV-infected Zimbabwean infants were tested for CMV and EBV at 6 weeks of age by real-time PCR; if positive, birth samples were retrieved where available to distinguish congenital and postnatal infection. The impact of co-infection on mortality through 6 months was estimated using Kaplan-Meier and Cox proportional hazards methods. RESULTS: At 6 weeks, 203/257 (79%) HIV-infected infants were CMV-positive; 27 (11%) had congenital CMV, 108 (42%) postnatal CMV and 68 (26%) indeterminate timing of infection. By 6 months, 37/108 (34%) infants with postnatal CMV versus 16/54 (30%) CMV-negative infants died (adjusted hazard ratio (aHR) 1.1 [95%CI 0.6, 2.2]). At 6 weeks, 33/257 (13%) HIV-infected infants had EBV co-infection; 6 (2%) had congenital EBV, 18 (7%) postnatal EBV and 9 (4%) indeterminate timing of infection. By 6 months, 5/18 (28%) infants with postnatal EBV versus 72/224 (32%) EBV-negative infants died (aHR 0.8 [95%CI 0.3, 2.3]). CONCLUSIONS: The vast majority of HIV-infants had acquired CMV by 6 weeks, and EBV co-infection occurred earlier than expected, with one in eight HIV-infected infants positive for EBV by 6 weeks. There was a high prevalence of congenital CMV infection and we identified 6 infants with congenital EBV infection, which has not previously been reported in Africa or in the context of HIV infection. Neither CMV nor EBV co-infection was associated with increased mortality.


Sujet(s)
Infections opportunistes liées au SIDA/épidémiologie , Infections à cytomégalovirus/épidémiologie , Infections à virus Epstein-Barr/épidémiologie , Infections opportunistes liées au SIDA/transmission , Adulte , Co-infection , Infections à cytomégalovirus/transmission , Infections à virus Epstein-Barr/transmission , Femelle , Humains , Nourrisson , Mortalité infantile , Transmission verticale de maladie infectieuse , Mâle , Zimbabwe
16.
PLoS Pathog ; 10(5): e1004068, 2014 May.
Article de Anglais | MEDLINE | ID: mdl-24853673

RÉSUMÉ

Polyclonal Epstein-Barr virus (EBV)-infected B cell line (lymphoblastoid cell lines; LCL)-stimulated T-cell preparations have been successfully used to treat EBV-positive post-transplant lymphoproliferative disorders (PTLD) in transplant recipients, but function and specificity of the CD4+ component are still poorly defined. Here, we assessed the tumor-protective potential of different CD4+ T-cell specificities in a PTLD-SCID mouse model. Injection of different virus-specific CD4+ T-cell clones showed that single specificities were capable of prolonging mouse survival and that the degree of tumor protection directly correlated with recognition of target cells in vitro. Surprisingly, some CD4+ T-cell clones promoted tumor development, suggesting that besides antigen recognition, still elusive functional differences exist among virus-specific T cells. Of several EBV-specific CD4+ T-cell clones tested, those directed against virion antigens proved most tumor-protective. However, enriching these specificities in LCL-stimulated preparations conferred no additional survival benefit. Instead, CD4+ T cells specific for unknown, probably self-antigens were identified as principal antitumoral effectors in LCL-stimulated T-cell lines. These results indicate that virion and still unidentified cellular antigens are crucial targets of the CD4+ T-cell response in this preclinical PTLD-model and that enriching the corresponding T-cell specificities in therapeutic preparations may enhance their clinical efficacy. Moreover, the expression in several EBV-negative B-cell lymphoma cell lines implies that these putative autoantigen(s) might also qualify as targets for T-cell-based immunotherapy of virus-negative B cell malignancies.


Sujet(s)
Autoantigènes/immunologie , Lymphocytes T CD4+/physiologie , Herpèsvirus humain de type 4/immunologie , Syndromes lymphoprolifératifs/immunologie , Syndromes lymphoprolifératifs/virologie , Transplantation de cellules souches de sang périphérique/effets indésirables , Animaux , Cellules cultivées , Modèles animaux de maladie humaine , Infections à virus Epstein-Barr/immunologie , Infections à virus Epstein-Barr/transmission , Herpèsvirus humain de type 4/physiologie , Humains , Souris , Souris de lignée C57BL , Souris SCID , Complications postopératoires/immunologie , Transplantation homologue/effets indésirables
17.
Eur J Haematol ; 91(3): 242-248, 2013 Sep.
Article de Anglais | MEDLINE | ID: mdl-23734904

RÉSUMÉ

BACKGROUND: Epstein-Barr virus (EBV)-infected T or NK cells cause chronic active EBV infection (CAEBV). Allogeneic hematopoietic stem cell transplantation (HSCT) is curative treatment for CAEBV patients. However, chemotherapy prior to HSCT and optimal conditioning regimen for allogeneic HSCT are still controversial. PATIENTS AND METHODS: We retrospectively analyzed five patients with CAEBV treated with reduced-intensity conditioning (RIC) consisted of fludarabine, cyclophosphamide, and low-dose total-body irradiation followed by allogeneic bone marrow transplantation in a single institute. Only one of five patients received chemotherapy prior to transplantation. We analyzed EBV-infected cells in a patient whose EBV load increased after HSCT by T-cell repertoire assay, separation of T-cell subpopulations, in situ hybridization and microsatellite analysis. RESULTS: All five patients achieved engraftment, complete chimera, and eradication of EBV load. All patients have been alive without any serious regimen-related toxicity for more than 16 months following HSCT. However, one patient transplanted from HLA-matched sibling donor developed clonal proliferation of CD4+ Vß3+ T cells caused by monoclonal EBV infection on day 99 after transplantation. Further analysis revealed that the CD4+ Vß3+ T cells selectively harbored EBV genome, and these infected cells were derived from donor T cells. CONCLUSIONS: Allogeneic HSCT with RIC is a safe and effective treatment for better overall survival and less regimen-related toxicity in patients with CAEBV. Our first pediatric case reported in the literature suggests that we should consider the possibility of persistent EBV infection in donor T cells as well as the relapse in recipient cells if EBV load increases after allogeneic HSCT.


Sujet(s)
Infections à virus Epstein-Barr/thérapie , Transplantation de cellules souches hématopoïétiques , Herpèsvirus humain de type 4 , Sous-populations de lymphocytes/virologie , Conditionnement pour greffe , Adolescent , Antigènes CD4/métabolisme , Enfant , Infections à virus Epstein-Barr/immunologie , Infections à virus Epstein-Barr/transmission , Infections à virus Epstein-Barr/virologie , Femelle , Herpèsvirus humain de type 4/génétique , Herpèsvirus humain de type 4/immunologie , Humains , Activation des lymphocytes , Sous-populations de lymphocytes/immunologie , Sous-populations de lymphocytes/métabolisme , Mâle , Récepteur lymphocytaire T antigène, alpha-bêta/métabolisme , Donneurs de tissus , Transplantation homologue , Résultat thérapeutique , Jeune adulte
18.
J Infect Dis ; 207(12): 1798-806, 2013 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-23493724

RÉSUMÉ

BACKGROUND: Human immunodeficiency virus (HIV) infection is a risk factor for Epstein-Barr virus (EBV)-associated lymphomas. Characterizing primary infection may elucidate risk factors for malignancy. METHODS: To describe clinical and virologic manifestations of primary EBV infection among infants born to HIV-infected women, specimens were utilized from a cohort study conducted in Nairobi, Kenya. HIV and EBV viral loads were measured serially in plasma. EBV serology was performed on EBV DNA-negative infants. Monthly clinical examinations were performed by pediatricians. RESULTS: The probability of EBV infection by 1 year of age was .78 (95% CI, .67-.88) in HIV-infected and .49 (95% CI, .35-.65) in HIV-uninfected infants (P < .0001). At 2 years, probability of EBV infection was .96 (95% CI, .89-.99) in HIV-infected infants. Peak EBV loads were higher in HIV-infected versus HIV-uninfected infants (median 2.6 vs 2.1 log10 copies/mL; P < .0001). The majority of HIV-infected infants had detectable EBV DNA for >3 months (79%). Primary EBV infection was associated with cough, fever, otitis media, pneumonia, hepatomegaly, splenomegaly, and hospitalization in HIV-infected infants; conjunctivitis and rhinorrhea in HIV-uninfected infants. CONCLUSIONS: EBV infection occurs early in infants born to HIV-infected women. HIV infection was associated with more frequent and higher quantity EBV DNA detection.


Sujet(s)
Infections à virus Epstein-Barr/épidémiologie , Infections à virus Epstein-Barr/transmission , Infections à VIH/complications , Herpèsvirus humain de type 4/isolement et purification , Transmission verticale de maladie infectieuse , Adulte , Anticorps antiviraux/sang , Études de cohortes , ADN viral/sang , Infections à virus Epstein-Barr/complications , Infections à virus Epstein-Barr/virologie , Femelle , Infections à VIH/transmission , Infections à VIH/virologie , Herpèsvirus humain de type 4/génétique , Herpèsvirus humain de type 4/immunologie , Humains , Incidence , Nourrisson , Kenya/épidémiologie , Études longitudinales , Mâle , Facteurs de risque , Charge virale , Virémie , Jeune adulte
20.
BMC Res Notes ; 5: 477, 2012 Sep 01.
Article de Anglais | MEDLINE | ID: mdl-22937830

RÉSUMÉ

BACKGROUND: Multiple viruses, including human immunodeficiency virus, Epstein Barr virus (EBV) and mouse mammary tumour virus have been identified in human milk. High risk human papillomavirus (HPV) sequences have been identified in breast cancer. The aim of this study is to determine if viral sequences are present in human milk from normal lactating women. FINDINGS: Standard (liquid) and in situ polymerase chain reaction (PCR) techniques were used to identify HPV and EBV in human milk samples from normal lactating Australian women who had no history of breast cancer.High risk human papillomavirus was identified in milk samples of 6 of 40 (15%) from normal lactating women - sequencing on four samples showed three were HPV 16 and one was HPV 18. Epstein Barr virus was identified in fourteen samples (33%). CONCLUSION: The presence of high risk HPV and EBV in human milk suggests the possibility of milk transmission of these viruses. However, given the rarity of viral associated malignancies in young people, it is possible but unlikely, that such transmission is associated with breast or other cancers.


Sujet(s)
ADN viral/génétique , Herpèsvirus humain de type 4/génétique , Papillomavirus humain de type 16/génétique , Papillomavirus humain de type 18/génétique , Lait humain/virologie , Adulte , Australie/épidémiologie , Séquence nucléotidique , ADN viral/isolement et purification , Infections à virus Epstein-Barr/épidémiologie , Infections à virus Epstein-Barr/transmission , Femelle , Humains , Lactation/physiologie , Données de séquences moléculaires , Mutation , Infections à papillomavirus/épidémiologie , Infections à papillomavirus/transmission , Réaction de polymérisation en chaîne , Risque
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