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1.
Ann Hematol ; 100(4): 865-878, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33547921

RESUMO

Post-transplantation lymphoproliferative disorder (PTLD) is a severe complication of haematopoietic stem cell transplantation (HSCT), occurring in a setting of immune suppression and dysregulation. The disease is in most cases driven by the reactivation of the Epstein-Barr virus (EBV), which induces B cell proliferation through different pathomechanisms. Beyond EBV, many factors, variably dependent on HSCT-related immunosuppression, contribute to the disease development. PTLDs share several features with primary lymphomas, though clinical manifestations may be different, frequently depending on extranodal involvement. According to the WHO classification, histologic examination is required for diagnosis, allowing also to distinguish among PTLD subtypes. However, in cases of severe and abrupt presentation, a diagnosis based on a combination of imaging studies and EBV-load determination is accepted. Therapies include prophylactic and pre-emptive interventions, aimed at eradicating EBV proliferation before symptoms onset, and targeted treatments. Among them, rituximab has emerged as first-line option, possibly combined with a reduction of immunosuppression, while EBV-specific cytotoxic T lymphocytes are effective and safe alternatives. Though prognosis remains poor, survival has markedly improved following the adoption of the aforementioned treatments. The validation of innovative, combined approaches is the future challenge.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transtornos Linfoproliferativos/etiologia , Adulto , Idoso , Linfócitos B/patologia , Linfócitos B/virologia , Criança , Diagnóstico Diferencial , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/imunologia , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Herpesvirus Humano 4/patogenicidade , Herpesvirus Humano 4/fisiologia , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Transtornos Linfoproliferativos/epidemiologia , Transtornos Linfoproliferativos/terapia , Transtornos Linfoproliferativos/virologia , MicroRNAs/genética , Pessoa de Meia-Idade , Mutação , Prognóstico , Fatores de Risco , Rituximab/uso terapêutico , Linfócitos T Citotóxicos/transplante , Condicionamento Pré-Transplante/efeitos adversos , Transplante Homólogo/efeitos adversos , Ativação Viral
2.
J Cancer Res Clin Oncol ; 147(3): 713-723, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33392659

RESUMO

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a rare epithelial carcinoma arising from the nasopharyngeal region. The pathogenesis of NPC is linked to Epstein-Barr virus (EBV) infection, although genetics and lifestyle factors appears to be also implicated. NKG2D is an immunoreceptor expressed by NK and T-cell subsets that recognizes MICA protein and other ligands on tumor cells. NKG2D interaction with MICA plays a role in the immunosurveillance to viruses and cancer. METHODS: We investigated potential associations between functional polymorphisms in NKG2D and MICA genes with NPC susceptibility. We conducted a case-control study including 255 Vietnamese patients with EBV + non-differentiated NPC and 220 healthy controls. RESULTS: We observed a significant association between the LNK/LNK genotype of rs1049174 (a variant associated with lower NKG2D receptor expression and reduced NK cell cytotoxicity) and increased susceptibility to NPC (adjusted OR = 1.66, 95% CI 1.07-2.59; p = 0.024). Similarly, the AA genotype of MICA rs2596542 was significantly associated with NPC (adjusted OR = 2.12; 95% CI 1.22-3.81; p = 0.009). In addition, tumor specimens of NPC patients with the AA genotype displayed a higher expression level of MICA proteins and showed higher EBV titers compared with tumor tissues from patients with the GG or GA genotypes. Higher EBV copy numbers were also observed in tumors with the A allele of MICA rs1051792 (also known as MICA-129 Met/Val) compared with those with the G allele; however, MICA rs1051792 variants were not associated with NPC susceptibility. These results suggest that genetic variants in components of the NKG2D axis may influence the individual susceptibility to EBV-induced NPC.


Assuntos
Infecções por Vírus Epstein-Barr/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/virologia , Adulto , Estudos de Casos e Controles , DNA Viral/análise , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/patologia , Feminino , Predisposição Genética para Doença , Variação Genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Antígenos de Histocompatibilidade Classe I/biossíntese , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Imuno-Histoquímica , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/imunologia , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/patologia , Polimorfismo de Nucleotídeo Único
3.
Res Vet Sci ; 134: 137-146, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33383491

RESUMO

"Humanized" immunodeficient mice generated via the transplantation of CD34+ human hematopoietic stem cells (hHSC) are an important preclinical model system. The triple transgenic NOD.Cg-PrkdcscidIl2rgtm1Wjl Tg(CMV-IL3,CSF2,KITLG)1Eav/MloySzJ (NSGS) mouse line is increasingly used as recipient for CD34+ hHSC engraftment. NSGS mice combine the features of the highly immunodeficient NSG mice with transgenic expression of the human myeloid stimulatory cytokines GM-CSF, IL-3, and Kit ligand. While generating humanized NSGS (huNSGS) mice from two independent cohorts, we encountered a fatal macrophage activation syndrome (MAS)-like phenotype resulting from the transplantation of CD34+ hHSC. huNSGS mice exhibiting this phenotype declined clinically starting at approximately 10 weeks following CD34+ hHSC engraftment, with all mice requiring euthanasia by 16 weeks. Gross changes comprised small, irregular liver, splenomegaly, cardiomegaly, and generalized pallor. Hematological abnormalities included severe thrombocytopenia and anemia. Pathologically, huNSGS spontaneously developed a disseminated histiocytosis with infiltrates of activated macrophages and hemophagocytosis predominantly affecting the liver, spleen, bone marrow, and pancreas. The infiltrates were chimeric with a mixture of human and mouse macrophages. Immunohistochemistry suggested activation of the inflammasome in both human and murine macrophages. Active Epstein-Barr virus infection was not a feature. Although the affected mice exhibited robust chimerism of the spleen and bone marrow, the phenotype often developed in the face of low chimerism of the peripheral blood. Given the high penetrance and early lethality associated with the MAS-like phenotype here described, we urge caution when considering the use of huNSGS mice for the development of long-term studies.


Assuntos
Síndrome de Ativação Macrofágica/patologia , Macrófagos/microbiologia , Animais , Antígenos CD34 , Proteína Quinase Ativada por DNA/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Herpesvirus Humano 4 , Histiocitose/imunologia , Humanos , Subunidade gama Comum de Receptores de Interleucina/imunologia , Síndrome de Ativação Macrofágica/imunologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas Recombinantes/imunologia , Fator de Células-Tronco/imunologia
4.
Nat Commun ; 11(1): 3849, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737300

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr Virus (EBV) establish life-long infections and are associated with malignancies. Striking geographic variation in incidence and the fact that virus alone is insufficient to cause disease, suggests other co-factors are involved. Here we present epidemiological analysis and genome-wide association study (GWAS) in 4365 individuals from an African population cohort, to assess the influence of host genetic and non-genetic factors on virus antibody responses. EBV/KSHV co-infection (OR = 5.71(1.58-7.12)), HIV positivity (OR = 2.22(1.32-3.73)) and living in a more rural area (OR = 1.38(1.01-1.89)) are strongly associated with immunogenicity. GWAS reveals associations with KSHV antibody response in the HLA-B/C region (p = 6.64 × 10-09). For EBV, associations are identified for VCA (rs71542439, p = 1.15 × 10-12). Human leucocyte antigen (HLA) and trans-ancestry fine-mapping substantiate that distinct variants in HLA-DQA1 (p = 5.24 × 10-44) are driving associations for EBNA-1 in Africa. This study highlights complex interactions between KSHV and EBV, in addition to distinct genetic architectures resulting in important differences in pathogenesis and transmission.


Assuntos
Anticorpos Antivirais/biossíntese , Resistência à Doença/genética , Infecções por Vírus Epstein-Barr/genética , Infecções por Henipavirus/genética , Interações Hospedeiro-Patógeno/genética , Sarcoma de Kaposi/genética , Adolescente , Adulto , Antígenos Virais/genética , Antígenos Virais/imunologia , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Coinfecção , Infecções por Vírus Epstein-Barr/epidemiologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Antígenos Nucleares do Vírus Epstein-Barr/genética , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Feminino , Expressão Gênica , Estudo de Associação Genômica Ampla , HIV/genética , HIV/imunologia , HIV/patogenicidade , Cadeias alfa de HLA-DQ/genética , Cadeias alfa de HLA-DQ/imunologia , Infecções por Henipavirus/epidemiologia , Infecções por Henipavirus/imunologia , Infecções por Henipavirus/virologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/patogenicidade , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/imunologia , Herpesvirus Humano 8/patogenicidade , Interações Hospedeiro-Patógeno/imunologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , População Rural , Sarcoma de Kaposi/epidemiologia , Sarcoma de Kaposi/imunologia , Sarcoma de Kaposi/virologia , Uganda/epidemiologia , População Urbana
5.
Hematol Oncol ; 38(4): 554-559, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32583904

RESUMO

Ruxolitinib is effective in myeloproliferative neoplasms (MPN) but can cause reactivation of silent infections. We aimed at evaluating viral load and T-cell responses to human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) in a cohort of 25 MPN patients treated with ruxolitinib. EBV-DNA and HCMV-DNA were quantified monthly using real-time polimerase chain reaction (PCR) on peripheral blood samples, and T-cell subsets were analyzed by flowcytometry. HCMV and EBV-directed T-cell responses were evaluated using the IFN-γ ELISPOT assay. Most patients had CD4+ and/or CD8+ T-cells below the normal range; these reductions were related to the duration of ruxolitinib treatment. In fact, reduced T-lymphocytes' subsets were found in 93% of patients treated for ≥5 years and in 45% of those treated for <5 years (P = .021). The former also had lower median numbers of CD4+ and CD8+ cells. Subclinical reactivation of EBV and HCMV occurred in 76% and 8% of patients. We observed a trend to an inverse relationship between EBV and CMV-specific CD4+ and CD8+ T-cell responses and viral load, and a trend to an inverse correlation with ruxolitinib dose. Therefore, our data suggest that the ruxolitinib treatment may interfere with immunosurveillance against EBV and HCMV.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Transtornos Mieloproliferativos/imunologia , Pirazóis/farmacologia , Ativação Viral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/virologia , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/imunologia , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/virologia , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Infecções por Vírus Epstein-Barr/virologia , Feminino , Seguimentos , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 4/imunologia , Humanos , Interferon gama/metabolismo , Masculino , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/virologia , Prognóstico , Taxa de Sobrevida , Carga Viral , Ativação Viral/efeitos dos fármacos
6.
J Virol ; 94(15)2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32461311

RESUMO

Cellular immunotherapy is a proven approach against Epstein-Barr virus (EBV)-driven lymphoproliferation in recipients of hematopoietic stem cells. Extending the applicability and improving the response rates of such therapy demands improving the knowledge base. We studied 23 healthy donors for specific CD4+ T cell responses against the viral tegument protein BNRF1 and found such T cells in all seropositive donors, establishing BNRF1 as an important immune target in EBV. We identified 18 novel immune epitopes from BNRF1, all of them generated by natural processing of the full-length protein from virus-transformed lymphoblastoid cell lines (LCL). BNRF1-specific CD4+ T cells were measured directly ex vivo by a cytokine-based method, thus providing a tool to study the interaction between immunity and infection in health and disease. T cells of the cytotoxic Th1 type inhibited the proliferation of autologous LCL as well as virus-driven transformation. We infer that they are important in limiting reactivations to subclinical levels during health and reducing virus propagation during disease. The information obtained from this work will feed into data sets that are indispensable in the design of patient-tailored immunotherapeutic approaches, thereby enabling the stride toward broader application of T cell therapy and improving clinical response rates.IMPORTANCE Epstein-Barr virus is carried by most humans and can cause life-threatening diseases. Virus-specific T cells have been used in different clinical settings with variable success rates. One way to improve immunotherapy is to better suit T cell generation protocols to viral targets available in different diseases. BNRF1 is present in viral particles and therefore likely available as a target for T cells in diseases with virus amplification. Here, we studied healthy Epstein-Barr virus (EBV) carriers for BNRF1 immunogenicity and report our results indicating BNRF1 to be a dominant target of the EBV-specific CD4+ T cell response. BNRF1-specific CD4+ T cells were found to be cytotoxic and capable of limiting EBV-driven B cell transformation in vitro The findings of this work contribute to forwarding our understanding of host-virus interactions during health and disease and are expected to find direct application in the generation of specific T cells for immunotherapy.


Assuntos
Epitopos de Linfócito T/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/imunologia , Células Th1/imunologia , Proteínas do Envelope Viral/imunologia , Linhagem Celular Transformada , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/terapia , Feminino , Humanos , Imunoterapia , Masculino , Células Th1/patologia
7.
Cell Mol Life Sci ; 77(21): 4315-4324, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32367191

RESUMO

Epstein-Barr virus (EBV) was the first human tumor virus being discovered and remains to date the only human pathogen that can transform cells in vitro. 55 years of EBV research have now brought us to the brink of an EBV vaccine. For this purpose, recombinant viral vectors and their heterologous prime-boost vaccinations, EBV-derived virus-like particles and viral envelope glycoprotein formulations are explored and are discussed in this review. Even so, cell-mediated immune control by cytotoxic lymphocytes protects healthy virus carriers from EBV-associated malignancies, antibodies might be able to prevent symptomatic primary infection, the most likely EBV-associated pathology against which EBV vaccines will be initially tested. Thus, the variety of EBV vaccines reflects the sophisticated life cycle of this human tumor virus and only vaccination in humans will finally be able to reveal the efficacy of these candidates. Nevertheless, the recently renewed efforts to develop an EBV vaccine and the long history of safe adoptive T cell transfer to treat EBV-associated malignancies suggest that this oncogenic γ-herpesvirus can be targeted by immunotherapies. Such vaccination should ideally implement the very same immune control that protects healthy EBV carriers.


Assuntos
Infecções por Vírus Epstein-Barr/prevenção & controle , Herpesvirus Humano 4/imunologia , Vacinas contra Herpesvirus/uso terapêutico , Animais , Anticorpos Neutralizantes/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Vacinas contra Herpesvirus/imunologia , Humanos , Vacinação , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/uso terapêutico , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/uso terapêutico
8.
Am J Surg Pathol ; 44(8): 1061-1072, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32317607

RESUMO

Systemic Epstein-Barr virus-positive T-cell and natural killer (NK)-cell lymphoproliferative diseases of childhood are a group of lethal diseases mostly affecting children and young adults. The Ohshima Grading System and the 2017 World Health Organization (WHO) classification have been used for classifying this spectrum, but these systems have not been validated externally and compared. Therefore, we examined 36 cases of systemic Epstein-Barr virus-positive T-cell and NK-cell lymphoproliferative diseases of childhood with long-term follow-up, from Southwest China, to systematically summarize the clinicopathologic features and to validate and compare the Ohshima Grading System and the 2017 WHO classification in discrimination ability, predictive accuracy, concordance indices, and explained variation. Clinically, our cohort showed severe manifestations and poor prognoses. Morphologically, the hematopoietic and lymphoid specimens showed proliferation of small-sized to medium-sized bland-looking lymphocytes that might mask disease severity, whereas other extranodal lesions showed a disorganized to obliterated architecture infiltrated by medium-sized to large-sized, subtle to obvious atypical cells, which may mimic extranodal NK/T-cell lymphoma. Immunophenotypically, our cases mainly originate from CD8 αß T cells. Therefore, clinical and pathologic features should be equally considered to avoid missed diagnosis or misdiagnosis. In addition, the 2017 WHO classification shows a flexible grasp of pathologic features, thus classifying some cases (polymorphic and monoclonal cases with fulminant course) more reasonably; thereby, it showed statistically improved results compared with the Ohshima Grading System. However, underestimating the risk of some polyclonal cases and imprecisely discriminating monoclonal cases at diagnosis are common dilemmas in both systems. Therefore, the construction of a comprehensive grading algorithm for improved prognostic value and precise diagnosis requires additional studies.


Assuntos
Infecções por Vírus Epstein-Barr/classificação , Herpesvirus Humano 4/genética , Células Matadoras Naturais/imunologia , Transtornos Linfoproliferativos/classificação , Linfócitos T/imunologia , Adolescente , Adulto , Idade de Início , Proliferação de Células , Criança , Pré-Escolar , China , Bases de Dados Factuais , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Genes Codificadores da Cadeia alfa de Receptores de Linfócitos T , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T , Humanos , Lactente , Células Matadoras Naturais/patologia , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/patologia , Transtornos Linfoproliferativos/virologia , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Viral/genética , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Linfócitos T/patologia , Fatores de Tempo , Adulto Jovem
9.
J Clin Neurosci ; 78: 284-290, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32331940

RESUMO

Intracranial peripherally enhancing lesions in immunosuppressed solid organ transplant recipients represent a unique diagnostic and management dilemma due to the vast array of differentials that demand consideration. Diagnosis of the underlying pathology is often guided by the use of magnetic resonance imaging (MRI). We present the first published case series of three cardiac transplant recipients with significantly atypical neuroradiological findings contrary to the tenets of contemporary literature. Our rare case series consists of: (1) A sterile Mycobacterium pyogenic abscess mimicking glioblastoma multiforme due to an immunosuppressed state (2) Epstein Barr Virus encephalitis masquerading as Central Nervous System Post-Transplant Lymphoproliferative Disorder (3) An unusual case of partially treated disseminated Nocardiosis warning of the need to consider the immunosuppressed state and partial treatment response obfuscating classical MRI appearances. We utilise these unprecedented cases as the basis of a literature review to understand the pathophysiology behind the peculiar imaging findings in this rarefied cohort of transplant recipients, and rationalise why the MRI findings in each instance contradicts the accepted imaging patterns. In the setting of potential unreliability of neuroradiology in this immunosuppressed unique subgroup, we hope to impart to clinicians that definitive diagnosis obtained by emergent neurosurgical intervention may be necessary to accurately and expediently guide further medical management.


Assuntos
Encefalite Viral/diagnóstico por imagem , Infecções por Vírus Epstein-Barr/diagnóstico por imagem , Transplante de Coração/efeitos adversos , Transtornos Linfoproliferativos/diagnóstico por imagem , Nocardiose/diagnóstico por imagem , Transplantados , Idoso , Encefalite Viral/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Transplante de Coração/tendências , Humanos , Hospedeiro Imunocomprometido/imunologia , Transtornos Linfoproliferativos/imunologia , Imagem por Ressonância Magnética/tendências , Masculino , Pessoa de Meia-Idade , Nocardiose/imunologia
10.
Am J Surg Pathol ; 44(9): 1173-1183, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32349049

RESUMO

Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoproliferation encompasses a broad range of clinicopathologic findings, including specific subtypes, for example, EBV mucocutaneous ulcer. Here we reassessed 36 cases of primary EBV diffuse large B-cell lymphomas (16 men and 20 women; median age, 69.5 y; range, 35 to 84 y), including 8 immunosuppressed patients (Lugano stage II-IV; median age, 74 y), 7 nonimmunosuppressed patients with stage I disease (median age, 69 y), and 21 nonimmunosuppressed patients with stage II-IV disease (median age, 69 y). All immunosuppressed patients exhibited iatrogenic immunodeficiency and an ulcerative appearance, with ulcer sites including the stomach (1 patient), small intestine (6 patients), and rectum (1 patient). Four patients were in the setting of treated lymphoma-associated immunosuppression. Immunosuppressed patients had higher incidences of intestinal involvement (P=0.001) and perforation (n=2) compared with advanced stage nonimmunosuppressed patients. Among nonimmunosuppressed stage I patients, lesions were restricted to the stomach, none showed multiple lesions or elevated serum lactate dehydrogenase, and the overall survival curve plateaued, although it was not statistically significant (P=0.0581). One nonimmunosuppressed stage I patient with a polypoid lesion exhibited spontaneous regression within 2 months after diagnosis, while another with bulky disease pursued an aggressive clinical course. Nonimmunosuppressed stage I cases without bulky masses may be considered EBV mucocutaneous ulcer with local progression. Our results demonstrated that primary EBV gastrointestinal diffuse large B-cell lymphoma could be delineated into 3 groups based on immune status and clinical stage, revealing distinguishing features useful as a pragmatic guide for diagnostic and therapeutic approaches.


Assuntos
Infecções por Vírus Epstein-Barr/virologia , Neoplasias Gastrointestinais/virologia , Herpesvirus Humano 4/genética , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Linfoma Difuso de Grandes Células B/virologia , RNA Viral/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/terapia , Feminino , Neoplasias Gastrointestinais/imunologia , Neoplasias Gastrointestinais/patologia , Neoplasias Gastrointestinais/terapia , Herpesvirus Humano 4/imunologia , Humanos , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/terapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Intervalo Livre de Progressão , Indução de Remissão , Estudos Retrospectivos , Fatores de Risco
11.
J Glob Health ; 10(1): 010404, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32257152

RESUMO

Background: Epstein-Barr virus (EBV) is an important human pathogen; it infects >90% people globally and is linked to infectious mononucleosis and several types of cancer. Vaccines against EBV are in development. In this study we present the first systematic review of the literature on risk factors for EBV infection, and discuss how they differ between settings, in order to improve our understanding of EBV epidemiology and aid the design of effective vaccination strategies. Methods: MEDLINE, Embase, and Web of Science were searched on 6th March 2017 for observational studies of risk factors for EBV infection. Studies were excluded if they were published before 2008 to ensure relevance to the modern day, given the importance of influencing future vaccination policies. There were no language restrictions. After title, abstract and full text screening, followed by checking the reference lists of included studies to identify further studies, data were extracted into standardised spreadsheets and quality assessed. A narrative synthesis was undertaken. Results: Seventy-seven papers met our inclusion criteria, including data from 31 countries. There was consistent evidence that EBV seroprevalence was associated with age, increasing throughout childhood and adolescence and remaining constant thereafter. EBV was generally acquired at younger ages in Asia than Europe/North America. There was also compelling evidence for an association between cytomegalovirus infection and EBV. Additional factors associated with EBV seroprevalence, albeit with less consistent evidence, included ethnicity, socioeconomic status, other chronic viral infections, and genetic variants of HLA and immune response genes. Conclusions: Our study is the first systematic review to draw together the global literature on the risk factors for EBV infection and includes an evaluation of the quality of the published evidence. Across the literature, the factors examined are diverse. In Asia, early vaccination of infants would be required to prevent EBV infection. In contrast, in Western countries a vaccine could be deployed later, particularly if it has only a short duration of protection and the intention was to protect against infectious mononucleosis. There is a lack of high-quality data on the prevalence and age of EBV infection outside of Europe, North America and South-East Asia, which are essential for informing effective vaccination policies in these settings.


Assuntos
Infecções por Vírus Epstein-Barr/prevenção & controle , Herpesvirus Humano 4/imunologia , Vacinas contra Herpesvirus/imunologia , Mononucleose Infecciosa/prevenção & controle , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/genética , Vacinas contra Herpesvirus/administração & dosagem , Vacinas contra Herpesvirus/genética , Humanos , Mononucleose Infecciosa/imunologia , Mononucleose Infecciosa/virologia , Políticas , Fatores de Risco , Vacinas
12.
Hum Genet ; 139(6-7): 885-901, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32152698

RESUMO

Epstein-Barr virus (EBV) is a ubiquitous human pathogen, infecting > 90% of the adult population. In the vast majority of healthy individuals, infection with EBV runs a relatively benign course. However, EBV is by no means a benign pathogen. Indeed, apart from being associated with at least seven different types of malignancies, EBV infection can cause severe and often fatal diseases-hemophagocytic lymphohistiocytosis, lymphoproliferative disease, B-cell lymphoma-in rare individuals with specific monogenic inborn errors of immunity. The discovery and detailed investigation of inborn errors of immunity characterized by heightened susceptibility to, or increased frequency of, EBV-induced disease have elegantly revealed cell types and signaling pathways that play critical and non-redundant roles in host-defense against EBV. These analyses have revealed not only mechanisms underlying EBV-induced disease in rare genetic conditions, but also identified molecules and pathways that could be targeted to treat severe EBV infection and pathological consequences in immunodeficient hosts, or even potentially enhance the efficacy of an EBV-specific vaccine.


Assuntos
Infecções por Vírus Epstein-Barr/complicações , Predisposição Genética para Doença , Herpesvirus Humano 4/imunologia , Interações Hospedeiro-Patógeno/genética , Síndromes de Imunodeficiência/complicações , Transtornos Linfoproliferativos/etiologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/genética , Humanos , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/virologia , Transtornos Linfoproliferativos/patologia , Transdução de Sinais
13.
Mol Immunol ; 120: 101-112, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32113130

RESUMO

Histocompatibility Leukocyte Antigens, or HLAs, are one of the most polymorphic molecules in humans. This high degree of polymorphism endows HLA molecules with the ability to present a vast array of peptides, an essential trait for responding to ever-evolving pathogens. Unlike classical HLA molecules (HLA-Ia), some non-classical HLA-Ib molecules, including HLA-E, are almost monomorphic. Several studies show HLA-E can present self-peptides originating from the leader sequence of other HLA molecules, which signals to our immune system that the cell is healthy. Therefore, it was traditionally thought that the chief role of HLA-E in the body was in immune surveillance. However, there is emerging evidence that HLA-E is also able to present pathogen-derived peptides to the adaptive immune system, namely T cells, in a manner that is similar to classical HLA-Ia molecules. Here we describe the early findings of this less conventional role of HLA-E in the adaptive immune system and its importance for immunity.


Assuntos
Antígenos de Histocompatibilidade Classe I/imunologia , Imunidade Adaptativa , Sequência de Aminoácidos , Apresentação do Antígeno/imunologia , Sítios de Ligação , Infecções por Citomegalovirus/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por HIV/imunologia , Antígeno HLA-A2/química , Antígeno HLA-A2/genética , Antígeno HLA-A2/imunologia , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Vigilância Imunológica , Células Matadoras Naturais/imunologia , Modelos Moleculares , Polimorfismo Genético , Conformação Proteica , Infecções por Salmonella/imunologia , Homologia de Sequência de Aminoácidos , Linfócitos T/imunologia , Tuberculose/imunologia
14.
Curr Med Sci ; 40(1): 168-171, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32166679

RESUMO

The study investigated the distribution of Epstein-Barr virus (EBV) EA-IgA, VCA-IgA, and EBVNA-IgG antibodies in a local population of Wuhan, China. Chemiluminescence immunoassay (CLIA) was used to detect EBV EA-IgA, VCA-IgA, and EBVNA-IgG antibodies in 972 subjects undergoing physical examination in Wuhan, and the results were analyzed. The detection rate of EBV was positively correlated with age. In the 972 cases, there was significant difference between different genders in the positive rate of VCA-IgA and EBVNA-IgG. Moreover, the positive rate of VCA-IgA and EBVNA-IgG was higher in men ≥ 60 years old than in those < 60 but no significant differences were found in three antibodies among various age groups. Our results suggested that the EBV infection should be intensively monitored in elderly people in Wuhan.


Assuntos
Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/imunologia , Imunoglobulina A/metabolismo , Imunoglobulina G/metabolismo , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Proteínas do Capsídeo/imunologia , China , Infecções por Vírus Epstein-Barr/imunologia , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Adulto Jovem
15.
J Immunol Res ; 2020: 4098235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32149157

RESUMO

Objectives: To explore effects of Epstein-Barr virus (EBV) infection on CD19+ B lymphocytes in patients with immunorelated pancytopenia (IRP). Methods: An enzyme-linked immunosorbent assay (ELISA) in vitro diagnostic kit was used to detect EBV capsid antigen- (CA-) IgG and VCA-IgM antibodies in the serum. We analyzed the EBV-DNA copies of CD19+ B lymphocyte by using real-time quantitative polymerase chain reaction (RT-qPCR). CD21, CD23, CD5, CD80, and CD86 receptors on the surfaces of CD19+ B cells were detected by flow cytometry (FCM). The correlation between these receptors and EBV-DNA copies were evaluated. Results: The results revealed that the positive rate of EBVCA-IgM and CD19+ B lymphocyte EBV-DNA copy in the IRP group were significantly higher than those in the control group (P < 0.05). CD19+ B lymphocyte EBV-DNA copies were also more abundant in IRP patients than in control subjects (P < 0.05). CD19+ B lymphocyte EBV-DNA copies were also more abundant in IRP patients than in control subjects (P < 0.05). CD19+ B lymphocyte EBV-DNA copies were also more abundant in IRP patients than in control subjects (. Conclusions: EBV infection may activate CD19+ B lymphocytes and further disrupt bone marrow hematopoiesis in IRP patients.


Assuntos
Linfócitos B/imunologia , Linfócitos B/virologia , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4 , Pancitopenia/etiologia , Adolescente , Adulto , Idoso , Antígenos CD19/metabolismo , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/metabolismo , Linfócitos B/metabolismo , Infecções por Vírus Epstein-Barr/diagnóstico , Infecções por Vírus Epstein-Barr/virologia , Feminino , Humanos , Imunoglobulina M/sangue , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Pancitopenia/sangue , Pancitopenia/metabolismo , Prognóstico , Adulto Jovem
16.
Biochemistry ; 59(12): 1252-1260, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32176479

RESUMO

Protein kinase R (PKR) is a key antiviral component of the innate immune pathway and is activated by viral double-stranded RNAs (dsRNAs). Adenovirus-associated RNA 1 (VAI) is an abundant, noncoding viral RNA that functions as a decoy by binding PKR but not inducing activation, thereby inhibiting the antiviral response. In VAI, coaxial stacking produces an extended helix that mediates high-affinity PKR binding but is too short to result in activation. Like adenovirus, Epstein-Barr virus produces high concentrations of a noncoding RNA, EBER1. Here, we compare interactions of PKR with VAI and EBER1 and present a structural model of EBER1. Both RNAs function as inhibitors of dsRNA-mediated PKR activation. However, EBER1 weakly activates PKR whereas VAI does not. PKR binds EBER1 more weakly than VAI. Assays at physiological ion concentrations indicate that both RNAs can accommodate two PKR monomers and induce PKR dimerization. A structural model of EBER1 was obtained using constraints derived from chemical structure probing and small-angle X-ray scattering experiments. The central stem of EBER1 coaxially stacks with stem loop 4 and stem loop 1 to form an extended RNA duplex of ∼32 bp that binds PKR and promotes activation. Our observations that EBER1 binds PKR much more weakly than VAI and exhibits weak PKR activation suggest that EBER1 is less well suited to function as an RNA decoy.


Assuntos
Herpesvirus Humano 4/genética , Interações entre Hospedeiro e Microrganismos/genética , RNA Viral/metabolismo , eIF-2 Quinase/genética , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/imunologia , Humanos , Imunidade Inata/genética , Modelos Moleculares , Conformação de Ácido Nucleico , Multimerização Proteica/genética , Multimerização Proteica/imunologia , Estabilidade de RNA , RNA Viral/química , Espalhamento a Baixo Ângulo , Difração de Raios X , eIF-2 Quinase/química , eIF-2 Quinase/imunologia , eIF-2 Quinase/metabolismo
17.
PLoS One ; 15(3): e0230374, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210468

RESUMO

Oxidative stress is suggested to be the crucial factor in diabetes mellitus type 2 (DM2) pathogenesis and in the development of diabetic complications. Patients with DM2 may be more susceptible to infections due to hyperglycaemia-induced virulence of various microorganisms. Several studies pointed that Epstein-Barr virus (EBV) infection is associated with reactive oxygen species (ROS) production and/or activation of signalling pathways connected with ROS. The present study analyzed serum activity of glutathione peroxidase (GPx) and superoxide dismutase (SOD) in DM2 patients with and without EBV infection. Blood and saliva were collected from 120 patients with DM2. EBV DNA was detected in the saliva using nested-PCR technique. Spectrophotometric methods were implemented to determine serum GPx and SOD activity with the use of diagnostic kits produced by Randox Laboratories. GPx and SOD activity was decreased in diabetic patients, with the lowest values in DM2 EBV-positive patients. There was correlation between GPx and SOD activity-with increased value of GPx, SOD activity was also rised. In patients with DM2 history longer than 10 years as well as in DM2 patients with obesity, antioxidant enzymes activity was decreased. Determination of examined parameters may be useful in diabetic patients with EBV infection and could be important prognostic factor.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Infecções por Vírus Epstein-Barr/sangue , Glutationa Peroxidase/sangue , Herpesvirus Humano 4/isolamento & purificação , Superóxido Dismutase/sangue , Adulto , DNA Viral/isolamento & purificação , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/imunologia , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Estudos de Viabilidade , Feminino , Glutationa Peroxidase/metabolismo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/imunologia , Prognóstico , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/imunologia , Superóxido Dismutase/metabolismo , Adulto Jovem
18.
J Virol ; 94(11)2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32213613

RESUMO

Interferon alpha (IFN-α) and IFN-ß are type I IFNs that are induced by virus infection and are important in the host's innate antiviral response. EBV infection activates multiple cell signaling pathways, resulting in the production of type I IFN which inhibits EBV infection and virus-induced B-cell transformation. We reported previously that EBV tegument protein BGLF2 activates p38 and enhances EBV reactivation. To further understand the role of BGLF2 in EBV infection, we used mass spectrometry to identify cellular proteins that interact with BGLF2. We found that BGLF2 binds to Tyk2 and confirmed this interaction by coimmunoprecipitation. BGLF2 blocked type I IFN-induced Tyk2, STAT1, and STAT3 phosphorylation and the expression of IFN-stimulated genes (ISGs) IRF1, IRF7, and MxA. In contrast, BGLF2 did not inhibit STAT1 phosphorylation induced by IFN-γ. Deletion of the carboxyl-terminal 66 amino acids of BGLF2 reduced the ability of the protein to repress type I IFN signaling. Treatment of gastric carcinoma and Raji cells with IFN-α blocked BZLF1 expression and EBV reactivation; however, expression of BGLF2 reduced the ability of IFN-α to inhibit BZLF1 expression and enhanced EBV reactivation. In summary, EBV BGLF2 interacts with Tyk2, inhibiting Tyk2, STAT1, and STAT3 phosphorylation and impairs type I IFN signaling; BGLF2 also counteracts the ability of IFN-α to suppress EBV reactivation.IMPORTANCE Type I interferons are important for controlling virus infection. We have found that the Epstein-Barr virus (EBV) BGLF2 tegument protein binds to a protein in the type I interferon signaling pathway Tyk2 and inhibits the expression of genes induced by type I interferons. Treatment of EBV-infected cells with type I interferon inhibits reactivation of the virus, while expression of EBV BGLF2 reduces the ability of type I interferon to inhibit virus reactivation. Thus, a tegument protein delivered to cells during virus infection inhibits the host's antiviral response and promotes virus reactivation of latently infected cells. Therefore, EBV BGLF2 might protect virus-infected cells from the type I interferon response in cells undergoing lytic virus replication.


Assuntos
Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/fisiologia , Interferon Tipo I/imunologia , Transdução de Sinais/imunologia , Proteínas Virais de Fusão/imunologia , Ativação Viral/imunologia , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/patologia , Células HEK293 , Humanos , Fator Regulador 1 de Interferon/genética , Fator Regulador 1 de Interferon/imunologia , Fator Regulador 7 de Interferon/genética , Fator Regulador 7 de Interferon/imunologia , Interferon Tipo I/genética , Interferon gama/genética , Interferon gama/imunologia , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/imunologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Transdução de Sinais/genética , TYK2 Quinase/genética , TYK2 Quinase/imunologia , Proteínas Virais de Fusão/genética , Ativação Viral/genética
19.
Sci Rep ; 10(1): 2814, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32071361

RESUMO

Autoantibodies, which are antibodies that target self-epitopes, have considerable diagnostic, prognostic and predictive value in specific autoimmune diseases. Various infectious agents have been linked via numerous mechanisms to the formation of different autoantibodies. Therefore, estimating the prevalence of autoantibodies and anti-infectious antibodies in different populations is of high importance. Different genetic and environmental pressures, such as these found in Ghana's different geographical provinces, may affect the prevalence of autoantibodies. In this study, we assessed the seroprevalence of a diverse panel of autoantibodies and anti-infectious antibodies among the healthy Ghanaian population and investigated possible environmental and genetic predispositions for autoantibodies and autoimmunity. The sera of 406 healthy individuals were obtained from Greater Accra, Upper West, Eastern and Volta regions. Multiplexed assay and chemiluminescent immunoassay techniques were utilized to assess the presence of a panel of autoantibodies and anti-infectious antibodies. We found a high prevalence of anti-HSV-1 IgG (91-100%), anti-EBNA IgG (81-93%) and anti-EBV-VCA IgG (97-100%) antibodies. The prevalence of ANA (at least one of: anti-dsDNA; anti-chromatin; anti-ribosomal-P; anti-Ro/SSA; anti-La/SSB; anti-centromere B; anti-Sm; anti-Sm/RNP; anti-Scl-70; anti-Jo1; anti-DFS70) was estimated at 14%. An inverse association between anti-HSV-2 antibodies and ANA (p = 0.044; adjusted OR = 0.398; CI [0.162-0.975]) was found, after adjusting for differences in gender, age, and familial history of autoimmune diseases. A trend towards reduced seroprevalence of anti-dsDNA antibodies among subjects who were positive for anti-HSV-2 antibodies was also noted (p = 0.1). In conclusion, the inverse association between anti-HSV-2 antibodies and ANA positivity suggests a possible protective role of HSV-2 infection against autoimmunity.


Assuntos
Anticorpos Antinucleares/sangue , Anticorpos Antifosfolipídeos/sangue , Anticorpos Antivirais/sangue , Doenças Autoimunes/epidemiologia , Infecções por Vírus Epstein-Barr/epidemiologia , Herpes Simples/epidemiologia , Adolescente , Adulto , Idoso , Doenças Autoimunes/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Feminino , Gana , Herpes Simples/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
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