RESUMO
Introduction: The Epstein-Barr virus (EBV) is an ubiquitous and oncogenic virus associated with the development of diseases such as infectious mononucleosis, Burkitt's lymphoma, nasopharyngeal carcinoma, and other neoplasms. Currently, two types are recognized: EBV-1 and EBV-2, which have genetic differences with their EBNA nuclear antigens. Likewise, due to the high degree of heterogeneity and variability found in the LMP1 protein of the virus, variants associated with pathogenesis or specific geographic regions have been described. Objective: To identify and characterize molecularly EBV variants detected in the oral cavity of 84 adolescents in Cali, Colombia. Materials and methods: Conventional PCR amplification, purification, and sequencing of the gen EBNA3C were carried out to typify the virus and the C-ter domain of the LMP1 protein to identify variants. We also conducted a phylogenetic and nucleotide variant analysis of the obtained sequences versus pathogenic or geographic variants reported in GenBank-NCBI. Results: The predominant viral subtype was EBV-1 (79%); 72.6% was grouped with the pathogenic variant Raji, derived from B lymphocytes of a patient with Burkitt>s lymphoma, 13.7% was related to a variant of Mediterranean origin, and 13.7% was not grouped with any of the reference variants. Conclusions: This is the first time that variants of LMP1-EBV have been identified in Cali, Colombia. Additional studies are necessary to characterize the unidentified variant and to determine if it is pathogenic or if it is just an isolate present in the city of Cali.
Introducción. El virus de Epstein-Barr (EBV) es un virus ubicuo y oncogénico, asociado con el desarrollo de enfermedades como la mononucleosis infecciosa, el linfoma de Burkitt, el carcinoma nasofaríngeo y otras neoplasias. Actualmente, se reconocen dos subtipos: EBV-1 y EBV- 2, que tienen diferencias genéticas con sus antígenos nucleares (Epstein-Barr Nuclear Antigens, EBNA). Debido a la gran heterogeneidad y variabilidad encontradas en la proteína LMP1 del virus, se han descrito variantes asociadas con ciertas enfermedades o con regiones geográficas específicas. Objetivo. Identificar y caracterizar molecularmente las variantes del EBV detectadas en la cavidad oral de 84 adolescentes de Cali, Colombia. Materiales y métodos. Se hizo la amplificación por reacción en cadena de la polimerasa (Polymerase Chain Reaction, PCR) convencional, así como la purificación y la secuenciación del gen EBNA3C se realizó para subtipificar el virus y del dominio C-ter de la proteína LMP1 para identificar variantes. Además, se llevó a cabo un análisis filogenético y de variantes nucleotídicas de las secuencias obtenidas comparadas con variantes patogénicas y geográficas reportadas en el GenBank (National Center for Biotechnology Information, NCBI). Resultados. El subtipo viral predominante fue el EBV-1 (79 %); el 72,6 % se agrupó con la variante patogénica Raji, derivada de linfocitos B de un paciente con linfoma de Burkitt; el 13,7 % se relacionó con una variante de origen geográfico del Mediterráneo y otro 13,7 % no se agrupó con ninguna de las variantes de referencia. Conclusiones. Este es el primer estudio que reporta variantes del gen LMP1-EBV en Cali, Colombia. Se requieren nuevos estudios para caracterizar la variante sin identificar y determinar si es patogénica o si es una variante geográfica presente exclusivamente en la ciudad.
Assuntos
Herpesvirus Humano 4/classificação , Boca/virologia , Adolescente , Colômbia , Humanos , Proteínas da Matriz Viral/análiseRESUMO
The Epstein-Barr virus (EBV) infects more than 90% of the human population, playing a key role in the origin and progression of malignant and non-malignant diseases. Many attempts have been made to classify EBV according to clinical or epidemiological information; however, these classifications show frequent incongruences. For instance, they use a small subset of genes for sorting strains but fail to consider the enormous genomic variability and abundant recombinant regions present in the EBV genome. These could lead to diversity overestimation, alter the tree topology and misinterpret viral types when classified, therefore, a reliable EBV phylogenetic classification is needed to minimize recombination signals. Recombination events occur 2.5-times more often than mutation events, suggesting that recombination has a much stronger impact than mutation in EBV genomic diversity, detected within common ancestral node positions. The Hierarchical Bayesian Analysis of Population Structure (hierBAPS) resulted in the differentiation of 12 EBV populations showed seven monophyletic and five paraphyletic. The populations identified were related to geographic location, of which three populations (EBV-p1/Asia/GC, EBV-p2/Asia II/Tumors and EBV-p4/China/NPC) were related to tumor development. Therefore, we proposed a new consistent and non-simplistic EBV classification, beneficial in minimizing the recombination signal in the phylogeny reconstruction, investigating geography relationship and even infer associations to human diseases. These EBV classifications could also be useful in developing diagnostic applications or defining which strains need epidemiological surveillance.
Assuntos
Infecções por Vírus Epstein-Barr/virologia , Genômica/métodos , Herpesvirus Humano 4/classificação , Recombinação Genética , Ásia , Teorema de Bayes , China , Monitoramento Epidemiológico , Variação Genética , Genoma Viral , Herpesvirus Humano 4/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Filogenia , Filogeografia , Sequenciamento Completo do GenomaRESUMO
A papilomatose laríngea é uma neoplasia benigna causada pelo papilomavírus humano (HPV), sendo os tipos 6 e 11 os mais comuns, e que ocorre em dois grupos etários, juvenil e adulto. A possível coinfecção viral tem sido sugerida em lesões de cabeça e pescoço; nesse sentido, o Epstein Barr vírus (EBV), que também apresenta tropismo por células epiteliais vem sendo estudado neste grupo de lesões. Os objetivos deste estudo foram genotipar os HPVs, investigar a presença de EBV-DNA por PCR e EBV-RNA por hibridização in situ. Além disso, associar a presença de EBV com a imunoexpressão de CD21, os resultados obtidos com a escala laringoscópica de Derkay et al. (1998) e com os dados clinicopatológicos. Oitenta casos de papilomatose laríngea, juvenil (n=36) e adulta (n=44), foram retrospectivamente analisados e subdivididos em grupos de menor e maior severidade, baseando-se na escala de Derkay. Todas as amostras foram HPV posivitas, com 49 casos HPV 6, 26 casos HPV 11, 4 casos HPV 6 e 11, e 1 caso HPV 16. A presença de EBV-DNA foi detectada em 9 amostras, entretanto EBV-RNA não foi não foi identificado em nenhuma amostra. Assim como a presença do EBV-DNA, a imunoexpressão de CD21 não se associou estatisticamente com quaisquer variáveis. A presença de HPV 6 foi mais comum em PLA e, o HPV 11 foi mais comum (p=0,02) e maior em casos de maior severidade (p=0,04), no grupo juvenil. A presença do EBV provavelmente não desempenha papel importante na progressão/severidade desta patologia(AU)
Laryngeal papillomatosis is a benign neoplasm caused by the human papillomavirus (HPV), been types 6 and 11 the most commonly related, and is divided into two groups: juvenile and adult. Viral coinfection has been suggested in head and neck lesions; in this sense, Epstein Barr virus (EBV), which also presents tropism for epithelial cells, has been studied in this group of lesions. The aims of this study are to perform HPV genotyping, investigate EBVDNA presence by PCR and EBV-RNA by in situ hybridization; and associate EBV presence with CD21 immunoexpression. Finally, the results were associated with Derkay laryngoscopic score. Eighty cases of laryngeal papillomatosis, juvenile (n = 36) and adult (n = 44) were retrospectively subdivided into low-risk and high-risk of severity based on the Derkay index. All samples were HPV-positive, with 49 cases of HPV 6, 26 cases of HPV 11, 4 cases of HPV 6 and 11, and 1 case of HPV 16. The presence of EBV-DNA was detected in 9 samples, however EBV-RNA was not identified in any sample. As the presence of EBV-DNA, the CD21 immunoexpression was not statistically associated with any variables. The presence of HPV 6 was more common in ALP, HPV 11 was more common (p = 0.02) and higher in cases of higher severity (p = 0.04) in juvenile group. The presence of EBV probably does not play an important role in the progression/severity of this pathology(AU)
Assuntos
Humanos , Papiloma/diagnóstico , Papillomaviridae/imunologia , Receptores de Complemento 3d/análise , Herpesvirus Humano 4/classificação , Agressão/efeitos dos fármacosRESUMO
El Virus de Epstein-Barr (VEB) es un herpes virus cuyo medio de transmisión es a través de secreciones de una persona portadora del virus, siendo el hombre el único huésped. La primo infección por lo general es asintomática o puede manifestarse como mononucleosis infecciosa con la triada clásica de fiebre, faringitis y adenopatías. Esta cursa con elevación leve y autolimitada de transaminasas, por lo que solo un 5% de los casos se ha asociado con hepatitis aguda colestásica. Presentamos a un paciente con una infección por virus de Epstein-Barr y hepatitis aguda colestásica con historia de aparición de una masa cervical lateral derecha. Al examen físico evidencia ictericia a nivel de escleras, mucosas y ambos miembros superiores. Niveles de bilirrubina en sangre elevados. Paciente con ultrasonido hepático y vías biliares normal, colangiopancreatografía retrograda endoscópica normal por lo que se procede a realizar pruebas serológicas para VEB siendo esta positiva. Se da tratamiento con ganciclovir, mejorando pruebas de función hepática y disminuyendo ictericia, teniendo así una evolución favorable del paciente...(AU)
Epstein-Barr Virus (EBV) is a herpes virus, whose means of transmission is through secretions of a person carrying the virus, the man being the only host. The cousin infection is usually asymptomatic or may manifest as infectious mononucleosis with the classical triad of fever, pharyngitis and lymphadenopathy. This is a mild and self-limiting elevation of transaminases, which means that only 5% of the cases have been associated with acute cholestasis hepatitis. We present a patient with an Epstein-Barr virus infection and acute cholestasis hepatitis with a history of the appearance of a right lateral cervical mass. Physical examination shows jaundice at the level of sclera, mucosa and both upper limbs. Elevated blood bilirubin levels. Patient with hepatic ultrasound and normal bile ducts, normal endoscopic retrograde cholangiopancreatography, so serological tests for EBV are performed and this is positive. Ganciclovir is given, improving liver function tests and decreasing jaundice, thus having a favorable evolution of the patient...(AU)
Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Colestase/virologia , Herpesvirus Humano 4/classificação , Herpesvirus Humano 4/patogenicidade , Mononucleose Infecciosa/tratamento farmacológico , Técnicas e Procedimentos Diagnósticos , GuatemalaRESUMO
The ubiquitous Epstein-Barr virus (EBV) is related to the development of several lymphoid and epithelial malignancies and is also the aetiological agent for infectious mononucleosis (IM). BZLF1, an immediate early gene, plays a key role in modulating the switch from latency to lytic replication, hence enabling viral propagation. Polymorphic variations in the coded protein have been studied in other geographical regions in a search for viral factors that are inherent to malignancies and differ from those present in benign infections. In the present study, in samples of paediatric patients with benign IM and paediatric patients with malignant lymphomas, we detected previously described sequence variations as well as distinctive sequence polymorphisms from our region. By means of phylogenetic reconstruction, we characterized new phylogenetically distinct variants. Moreover, we described an association between specific variants and the studied pathologies in our region, particularly variant BZLF1-A2 with lymphomas and BZLF1-C with IM. Additionally, length polymorphisms within intron 1 were also assessed and compared between pathologies resulting in an association between 29-bp repeated units and lymphomas. In conclusion, this is the first report to characterize BZLF1 gene polymorphisms in paediatric patients from our geographical region and to suggest the association of these polymorphisms with malignant lymphomas.
Assuntos
Herpesvirus Humano 4/classificação , Herpesvirus Humano 4/genética , Mononucleose Infecciosa/virologia , Linfoma/virologia , Polimorfismo Genético , Neoplasias Cutâneas/virologia , Transativadores/genética , Adolescente , Criança , Pré-Escolar , Feminino , Herpesvirus Humano 4/patogenicidade , Humanos , Lactente , Masculino , FilogeografiaRESUMO
The Epstein Barr virus (EBV) is associated with several lymphoid and epithelial malignancies such as Hodgkin and Burkitt lymphoma or nasopharyngeal carcinoma and it is also the etiological agent of infectious mononucleosis (IM). Transcriptional regulation of the viral oncoprotein LMP1, remains yet not fully understood. LMP1 expression can be initiated in an EBNA2 dependent or independent manner from ED-L1 or LT-R1 promoters. It has been proposed that sequence variation at ED-L1 region could be an important factor concerning LMP1 expression. In order to characterize the natural sequence variation of the ED-L1 promoter, and its relationship with neoplasia, 44 pediatric patients, 17 IM and 27 EBV-associated lymphoma cases from Argentina, were studied. Phylogenetic analysis showed 4 main clusters, namely B95.8, Raji, Cao and P3HR1. Most isolates, 80.3%, conformed the B95.8 group. Co-infection with more than one viral variant was detected in 5/17 IM cases, but no co-infections were detected among lymphoma cases. Moreover, co-infected IM cases exhibited differences between the ED-L1 sequences obtained from different anatomical compartments. Mutations confined to transcription factor binding sites such as SP1/SP3, CRE, AP2, C/EBP were found in similar proportions in 23 isolates from both benign and malignant samples, rendering the distribution of these mutations not significant among malignant samples.
Assuntos
Infecções por Vírus Epstein-Barr/virologia , Variação Genética , Herpesvirus Humano 4/genética , Regiões Promotoras Genéticas , Proteínas da Matriz Viral/genética , Adolescente , Criança , Pré-Escolar , Feminino , Herpesvirus Humano 4/classificação , Humanos , Lactente , Mononucleose Infecciosa/virologia , Linfoma/virologia , Masculino , Dados de Sequência Molecular , FilogeniaRESUMO
Extranodal natural killer/T-cell lymphoma, nasal type (NK/TCL) is more prevalent in Asia and in some areas of South and Central America, but it is rarely seen in the United States and Europe. In this study, a series of 122 cases of NK/TCL from Brazil was analyzed with respect to clinicopathologic features. Clinical characteristics and geographic distribution were evaluated in 97 cases of nasal/nasopharyngeal region and 23 cases in extranasal sites including 6 nodal cases. Clinical staging and follow-up information was available in a subset of 21 patients. All cases harbored Epstein-Barr virus (EBV), 95% and 85% expressed cytoplasmic CD3 and CD56, respectively, and all cases were positive for at least 1 marker for cytotoxic granules. The global distribution of EBV subtypes showed predominance of strain subtype A, 89%, and subtype B, 11%. No dual infections were detected. TCR-γ TCR-gene rearrangement was observed in 7 cases; all of them extranodal. Three of TCR-γ(+) cases showed EBV subtype A. Two TCR-γ(+)/CD56(+) cases showed EBV subtype B. Geographic distribution of NK/TCL showed higher frequency in the southeast and northeast regions of Brazil. Striking differences among geographic regions were seen with the vast majority of EBV subtype B (86%) occurring in the south and southeast regions.
Assuntos
Herpesvirus Humano 4/classificação , Linfoma Extranodal de Células T-NK/virologia , Linfoma de Células T/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Distribuição de Qui-Quadrado , Criança , DNA Viral/isolamento & purificação , Feminino , Rearranjo Gênico da Cadeia gama dos Receptores de Antígenos dos Linfócitos T , Genes Codificadores da Cadeia gama de Receptores de Linfócitos T , Herpesvirus Humano 4/genética , Humanos , Imuno-Histoquímica , Hibridização In Situ , Estimativa de Kaplan-Meier , Linfonodos/patologia , Linfonodos/virologia , Linfoma Extranodal de Células T-NK/genética , Linfoma Extranodal de Células T-NK/mortalidade , Linfoma Extranodal de Células T-NK/patologia , Linfoma de Células T/genética , Linfoma de Células T/mortalidade , Linfoma de Células T/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Prognóstico , Características de Residência , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Análise Serial de Tecidos , Adulto JovemRESUMO
Epstein-Barr virus (EBV) is related to the development of lymphomas and is also the etiological agent for infectious mononucleosis (IM). Sequence variation of the EBNA1 gene, consistently expressed in all EBV-positive cells, has been widely studied. Based on the amino acid at codon 487 five major EBNA1 variants have been described, two closely related prototypic variants (P-ala and P-thr) and three variant sequences (V-leu, V-val, and V-pro). Sub-variants were then further classified based on mutations other than the originally described. While several studies proposed associations with tumors and/or anatomical compartments, others argued in favor of a geographical distribution of these variants. In the present study, EBNA1 variants in 11 pediatric patients with IM and 19 pediatric EBV lymphomas from Argentina were compared as representatives of benign and malignant infection in children, respectively. A 3-month follow-up study of EBNA1 variants in peripheral blood cells and in oral secretions of patients with IM was performed. A new V-ala variant which includes five V-ala sub-variants and three new V-leu sub-variants was described. These data favor the geographical association hypothesis since no evidence for a preferential compartment distribution of EBNA1 variants and sub-variants was found. This is the first study to characterize EBNA1 variants in pediatric patients with infection mononucleosis worldwide.
Assuntos
Infecções por Vírus Epstein-Barr/epidemiologia , Infecções por Vírus Epstein-Barr/virologia , Antígenos Nucleares do Vírus Epstein-Barr/genética , Herpesvirus Humano 4/classificação , Herpesvirus Humano 4/genética , Polimorfismo Genético , Adolescente , Argentina/epidemiologia , Sangue/virologia , Secreções Corporais/virologia , Pré-Escolar , Análise por Conglomerados , DNA Viral/química , DNA Viral/genética , Feminino , Genótipo , Herpesvirus Humano 4/isolamento & purificação , Humanos , Linfócitos/virologia , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Nariz/virologia , Filogenia , Análise de Sequência de DNARESUMO
Burkitt lymphoma (BL) is a highly aggressive non-Hodgkin lymphoma with a consistent MYC translocation. Epstein-Barr virus (EBV) has been associated with BL at different frequencies, depending on the clinical variant and geographic regions. This is a large-scale study of BL in Brazil, including 234 patients from 5 geographic regions that are widely disparate socioeconomically, including pediatric (61.1%) and adult (37.6%) populations. EBV was present in 52.6% of all BL cases, varying from 29% (12/42) in the South to 76% (13/17) in the North. Most of the cases were EBV type A. The frequency was higher in the pediatric group, and EBV association within this age range predominated in all regions except the South. Expression of p53 protein was observed in 16.2%, and only rare cases showed p63 expression. BL in Brazil is regionally distinct and has a low incidence of p53 overexpression and a higher-than-expected association with EBV in sporadic cases.
Assuntos
Linfoma de Burkitt/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Linfoma de Burkitt/virologia , Criança , Pré-Escolar , Feminino , Geografia , Herpesvirus Humano 4/classificação , Humanos , Imuno-Histoquímica , Hibridização In Situ , Hibridização in Situ Fluorescente , Lactente , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Proteína Supressora de Tumor p53/biossínteseRESUMO
Epstein-Barr virus (EBV), the causative agent of infectious mononucleosis, plays a significant role as a cofactor in the process of tumorigenesis, and has consistently been associated with a variety of malignancies especially in immunocompromised patients. Forty-four children and adolescents (21 liver transplant patients, 7 heart transplant, 5 AIDS, 3 autoimmune hepatitis, 2 nephritic syndromes, 2 medullar aplasia, 2 primary immunodeficiency disorder patients, 1 thrombocytopenic purpura and 1 systemic lupus erythematosus) presenting with chronic active EBV infection (VCA-IgM persistently positive; VCA-IgG > 20 AU/mL and positive IgG _ EBNA) had peripheral blood samples obtained during clinically characterized EBV reactivation episodes. DNA samples were amplified in order to detect and type EBV on the basis of the EBNA-2 sequence (EBNA2 protein is essential for EBV-driven immortalization of B lymphocytes). Although we have found a predominance of type 1 EBNA-2 virus (33/44; 75%), 10 patients (22.73%) carried type 2 EBNA-2, and one liver transplant patient (2.27%) a mixture of the two types, the higher proportion of type 2 EBV, as well as the finding of one patient bearing the two types is in agreement with other reports held on lymphoproliferative disorder (LPD) patients, which analyzed tumor biopsies. We conclude that EBNA-2 detection and typing can be performed in peripheral blood samples, and the high prevalence of type 2 in our casuistic indicates that this population is actually at risk of developing LPD, and should be monitored.