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1.
Virology ; 587: 109847, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37515946

RESUMO

Epstein-Barr virus (EBV) is an usually harmless virus whose oncogenic properties in vitro are related to its ability to transform lymphoid cells, and, in consequence, it can be associated with lymphomas. Since a few studies detected EBV presence in supposedly EBV-negative lymphomas, our aim was to evaluate EBV presence by sensitive gene expression assays in the tonsils from healthy pediatric donors from a region with high incidence of EBV-associated lymphomas. EBERs transcripts were detected by View RNA ISH in all cases, even in cases assessed negative by widely used in situ hybridization. The presence of LMP1 transcripts was proved in 93% of cases, co-expressed with EBNA2 in 30%. In this study, evidence for the expression of different latent and lytic viral genes in a population of young age of primary infection, detected with more sensitive methods, in particular at the germinal center, where most EBV-associated lymphomas originate, was provided.

2.
Neurologia (Engl Ed) ; 2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35882307

RESUMO

BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) is characterised by recurrent attacks of optic neuritis and transverse myelitis. The purpose of this work was to identify the incidence and prevalence of NMOSD and its clinical characteristics in the population treated for demyelinating diseases in Western Mexico. MATERIAL AND METHOD: A descriptive, retrospective study was carried out in the Department of Neurology, at the Sub-specialty Medical Unit, Specialties Hospital (known by its Spanish abbreviation UMAE-HE), of the National Western Medical Center (CMNO), Mexican Institute of Social Security (IMSS). A review of the electronic files for all patients with a diagnosis of NMOSD in 2019, was carried out in the State of Jalisco, Mexico. RESULTS: Fifty-eight patients with NMOSD were included in the study. The incidence was 0.71/100 000 (CI 0.60-0.85) and the prevalence was 1.09/100 000 (CI 0.84-1.42). There were 79.3% women, and 20.6% were men (P = .01). All (100%) patients presented with anti-aquaporin-4 immunoglobulin G, and 89.6% showed seropositivity for anti-aquaporin-4 (CI 82.6-94.9). Magnetic resonance imaging was performed on 100% of patients, where 34.4% were normal, and 65.5% (38) abnormal, presenting with non-specific subcortical lesions (P = 0.04). The initial clinical presentation was optic neuritis (ON) in 58.6%; where 31.0% was bilateral ON, 20.7% was left ON, and 6.9% were right ON; transverse myelitis in 26.0%, area postrema syndrome (APS) in 10.3%, among others. CONCLUSIONS: The incidence of NMOSD exceeds 0.71/100 000, the prevalence is low at 1.09/100 000, and NMOSD is predominantly found in women.

3.
J Virol ; 96(1): e0143421, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34643432

RESUMO

Macrophages can be polarized toward a proinflammatory phenotype (M1) (CD68+) or to an anti-inflammatory one (M2) (CD163+). Polarization can be triggered by cytokines such as IFN-γ for M1, or IL-10 and TGF-ß, for M2. In the context of pediatric Epstein Barr virus (EBV) infection, little is known about macrophage polarization in EBV primary or persistent infection. When studying tonsils of patients undergoing primary infection (PI), healthy carrier (HC), reactivation (R), and not infected (NI), M1 profile prevailed in all infection status. However, an increase in M2 cells was observed in those patients with broader expression of latency antigens, in particular EBNA2. Tonsils from primary infected patients showed an increased IL-10 expression, whereas, unexpectedly, TGF-ß expression correlated with M1 marker. Furthermore, an inverse correlation was demonstrated between CD68 and IFN-γ. Therefore, in the context of asymptomatic infection in children, M1 macrophage polarization prevails, even in the presence of IL-10 and TGF-Ꞵ immunomodulatory cytokines, and it might be independent from lymphomagenesis process. Our finding indicates that macrophages may have a significant plasticity in response to different types of extrinsic stimuli, and further studies are required to investigate M1 polarization under anti-inflammatory stimuli. IMPORTANCE Most studies on Epstein Barr virus (EBV) primary infection have been performed in adolescents and young adult populations with Infectious Mononucleosis (IM) in developed countries. Furthermore, studies related to macrophage polarization were assessed in EBV-associated lymphomas, but little is known about macrophage polarization in the context of primary infection at the site of viral entry and replication, the tonsils. Therefore, the aim of this study was to characterize macrophage response in children undergoing EBV primary or persistent infection, in order to enlighten the role of macrophages in viral pathogenesis, in a population with a high incidence of EBV-associated lymphomas in children younger than 10 years old. This study may contribute to explain, at least in part, the asymptomatic viral infection in children from an underdeveloped region, given that M1 polarization pattern prevails, but in a regulatory environment.


Assuntos
Microambiente Celular/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/fisiologia , Imunomodulação , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Adolescente , Antígenos Virais/imunologia , Biomarcadores , Criança , Pré-Escolar , Citocinas/metabolismo , Infecções por Vírus Epstein-Barr/diagnóstico , Feminino , Interações Hospedeiro-Patógeno/imunologia , Humanos , Lactente , Macrófagos/metabolismo , Masculino , Testes Sorológicos , Carga Viral , Proteínas Virais/imunologia
4.
Cancer Immunol Immunother ; 70(6): 1519-1526, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33184699

RESUMO

BACKGROUND: Classic Hodgkin lymphoma (cHL) is a lymphoid malignancy in which the microenvironment, where the neoplastic cells are immersed, contributes to the lymphomagenesis process. Epstein-Barr virus (EBV) presence also influences cHL microenvironment composition and contributes to pathogenesis. An increase in PDL1 expression in tumor cells and at the microenvironment was demonstrated in adult cHL. Therefore, our aim was to assess PD1/PDL1 pathway and EBV influence on this pathway in pediatric cHL, given that in Argentina, our group proved a higher incidence of EBV-associated pediatric lymphoma in children. METHODS: For that purpose, EBV presence was assessed by in situ hybridization, whereas PD1 and PDL1 expressions were studied by immunohistochemistry. PDL1 genetic alterations were analyzed by FISH, and survival was evaluated for PD1 and PDL1 expressions. RESULTS: EBV presence demonstrated no influence neither on PD1 expression at the microenvironment nor on PDL1 expression at HRS tumor cells. Unexpectedly, only 38% pediatric cHL displayed PDL1 genetic alterations by FISH, and no difference was observed regarding EBV presence. However, in EBV-related cHL cases, a higher number of PDL1 + cells were detected at the microenvironment. CONCLUSION: Even though a high cytotoxic environment was previously described in EBV-related pediatric cHL, it might be counterbalanced by an immunoregulatory micro-environmental PDL1 + niche. This regulation may render a cytotoxic milieu that unsuccessfully try to eliminate EBV + Hodgkin Reed Sternberg tumor cells in pediatric patients.


Assuntos
Antígeno B7-H1/metabolismo , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/epidemiologia , Microambiente Tumoral/imunologia , Adolescente , Argentina/epidemiologia , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/virologia , Feminino , Seguimentos , Doença de Hodgkin/metabolismo , Doença de Hodgkin/patologia , Doença de Hodgkin/virologia , Humanos , Masculino , Prognóstico , Células de Reed-Sternberg , Taxa de Sobrevida
5.
Int J Infect Dis ; 93: 139-145, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32004689

RESUMO

BACKGROUND: In developing countries, Epstein-Barr virus (EBV) infection is mostly asymptomatic in early childhood. EBV persistence may lead to different malignancies, such as B cell derived lymphomas. In Argentina, most children are seropositive at three years and an increased association between EBV and lymphoma was proved in children under 10 years old by our group. OBJECTIVE: Our aim was to characterize EBV infection at the site of entry and reactivation of viral infection -the tonsils- in order to better understand the mechanism of viral persistence in pediatric patients. METHODS: A cohort of 54 patients was described. We assessed specific antibodies profiles in sera; viral proteins presence by IHC on FFPE samples and EBV type from fresh tissue. RESULTS: EBV type 1 was prevalent, mostly in the youngest patients. Asymptomatic primary infected patients presented higher viral loads and Latency 0/I or II patterns, whereas the Latency III pattern was observed mostly in healthy carriers. There were no differences between groups in the expression of viral lytic antigens. This study discloses new features in patients undergoing primary infection from a developing population. Low viral inoculum and restricted viral antigen expression may be responsible for the lack of symptoms in children from our country.


Assuntos
Infecções por Vírus Epstein-Barr/virologia , Adolescente , Anticorpos Antivirais/sangue , Antígenos Virais/metabolismo , Argentina , Criança , Pré-Escolar , Países em Desenvolvimento , Feminino , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/isolamento & purificação , Herpesvirus Humano 4/metabolismo , Humanos , Lactente , Masculino , Tonsila Palatina/virologia , Carga Viral , Proteínas Virais/metabolismo , Latência Viral
6.
Sci Rep ; 9(1): 12687, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481738

RESUMO

The microenvironment in classical Hodgkin lymphoma (cHL) comprises a mixture of different types of cells, which are responsible for lymphoma pathogenesis and progression. Even though microenvironment composition in adult cHL has been largely studied, only few groups studied pediatric cHL, in which both Epstein Barr virus (EBV) infection and age may display a role in their pathogenesis. Furthermore, our group described that EBV is significantly associated with cHL in Argentina in patients under the age of 10 years old. For that reason, our aim was to describe the microenvironment composition in 46 pediatric cHL patients. M1-like polarization status prevailed in the whole series independently of EBV association. On the other hand, in children older than 10 years, a tolerogenic environment illustrated by higher FOXP3 expression was proved, accompanied by a macrophage polarization status towards M2. In contrast, in children younger than 10 years, M1-like was prevalent, along with an increase in cytotoxic GrB+ cells. This study supports the notion that pediatric cHL exhibits a particular tumor microenvironment composition.


Assuntos
Doença de Hodgkin/patologia , Macrófagos/imunologia , Adolescente , Argentina , Criança , Pré-Escolar , Análise por Conglomerados , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Fatores de Transcrição Forkhead/metabolismo , Granzimas/metabolismo , Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/etiologia , Doença de Hodgkin/imunologia , Humanos , Ativação de Macrófagos , Macrófagos/citologia , Macrófagos/metabolismo , Microambiente Tumoral
7.
Clin Microbiol Infect ; 20(12): O998-1009, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24942073

RESUMO

Mechanisms leading to liver damage in chronic hepatitis C (CHC) are being discussed, but both the immune system and the virus are involved. The aim of this study was to evaluate intrahepatic viral infection, apoptosis and portal and periportal/interface infiltrate in paediatric and adult patients to elucidate the pathogenesis of chronic hepatitis C. HCV-infected, activated caspase-3(+) and TUNEL(+) hepatocytes, as well as total, CD4(+), CD8(+), Foxp3(+) and CD20(+) lymphocytes infiltrating portal and periportal/interface tracts were evaluated in 27 paediatric and 32 adult liver samples by immunohistochemistry or immunofluorescence. The number of infected hepatocytes was higher in paediatric than in adult samples (p 0.0078). In children, they correlated with apoptotic hepatocytes (activated caspase-3(+) r = 0.74, p < 0.0001; TUNEL(+) r = 0.606, p 0.0017). Also, infected (p = 0.026) and apoptotic hepatocytes (p = 0.03) were associated with the severity of fibrosis. In adults, activated caspase-3(+) cell count was increased in severe hepatitis (p = 0.009). Total, CD4(+), CD8(+) and Foxp3(+) lymphocyte count was higher in adult samples (p < 0.05). Paediatric CD8(+) cells correlated with infected (r = 0.495, p 0.04) and TUNEL(+) hepatocytes (r = 0.474, p = 0.047), while adult ones correlated with activated caspase-3(+) hepatocytes (r = 0.387, p 0.04). In adults, CD8(+) was associated with hepatitis severity (p < 0.0001) and correlated with inflammatory activity (CD8(+) r = 0.639, p 0.0003). HCV, apoptosis and immune response proved to be involved in CHC pathogenesis of both paediatric and adult patients. However, liver injury in paediatric CHC would be largely associated with a viral cytopathic effect mediated by apoptosis, while in adults it would be mainly associated with an exacerbated immune response.


Assuntos
Hepatite C Crônica/patologia , Fígado/patologia , Adolescente , Adulto , Fatores Etários , Idoso , Apoptose , Criança , Pré-Escolar , Feminino , Imunofluorescência , Hepatócitos/patologia , Humanos , Imuno-Histoquímica , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia
8.
Int J Cancer ; 135(12): 2816-24, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24789501

RESUMO

Diffuse large B-cell lymphoma (DLBCL), the most common group of malignant lymphomas, account for 30% of adult non-Hodgkin lymphomas. The 2008 World Health Organization (WHO) classification included a new entity, Epstein-Barr virus (EBV)+ DLBCL of the elderly, affecting patients aged 50 years or older. However, some reports of younger EBV+ DLBCL cases, without evidence of underlying immunosuppression, can be found. The role of EBV in tumor microenvironment composition in DLBCL is still not well understood. Our aim was to assess EBV presence and latency pattern as well as tumor T-cell population in an adult DLBCL series of Argentina. The study was conducted on biopsies from 75 DLBCL patients. EBERs expression was performed by in situ hybridization, while EBV gene expression was analyzed using real-time polymerase chain reaction. LMP1, LMP2A, EBNA2, EBNA3A, CD4, CD8 and Foxp3 expression was assessed by immunohistochemistry. Nine percent of cases showed EBV expression, with similar frequency among patients younger than 50 years and 50 years or older (13% and 8%, respectively). T-cell subsets were not altered by EBV presence. Latency type II was the most frequently observed, together with lytic gene expression in EBV+ DLBCL, with ≥20% of EBERs+ cells. These findings suggest that EBV+ DLBCL in our series was similar to the previously described in Asia and Latin-America, displaying latency II or III expression profile and no age-specific characteristics. Finally, EBV+ DLBCL may be an entity that is not only restricted to patients who are older than 50 years of age, in consequence the age cutoff revision may be a current goal.


Assuntos
Regulação Neoplásica da Expressão Gênica , Herpesvirus Humano 4 , Linfoma Difuso de Grandes Células B/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Argentina , Biópsia , Estudos de Coortes , Feminino , Humanos , Imunossupressores/farmacologia , Hibridização In Situ , Linfoma Difuso de Grandes Células B/epidemiologia , Linfoma Difuso de Grandes Células B/metabolismo , Masculino , Pessoa de Meia-Idade , Prevalência , Linfócitos T/citologia , Adulto Jovem
9.
Clin Microbiol Infect ; 20(11): O861-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24666405

RESUMO

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 , Filogeografia
10.
Cancer Lett ; 307(2): 221-6, 2011 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-21546156

RESUMO

In this study, we investigated Epstein Barr virus (EBV) presence, associated to proliferation and apoptosis proteins in pediatric B-cell Non-Hodgkin lymphoma (B-NHL). EBERs, Ki67, active caspase 3, Bax and Bcl2 were analyzed on B-NHL tissue from 40 patients. Forty percent showed EBV expression, significantly higher among patients ⩽10years (P=0.027), and associated with immunosuppression (P=0.020), but not associated apotosis markers. However, EBV was associated with a worse event-free survival (P=0.016), particularly under immunosuppression. Even though EBV did not seem to alter apoptotic pathways, it exhibited survival disadvantage and could be an important cofactor in B-cell lymphomagenesis in younger children.


Assuntos
Herpesvirus Humano 4/fisiologia , Linfoma de Células B/patologia , Criança , Feminino , Humanos , Imuno-Histoquímica , Hibridização In Situ , Linfoma de Células B/virologia , Masculino , Resultado do Tratamento
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