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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

The role of Epstein-Barr virus in nasopharyngeal carcinoma tumorigenesis. / CUHK electronic theses & dissertations collection

January 2007 (has links)
A comprehensive immunohistochemical study was carried out to investigate the phenotypes and prevalence of intraepithelial lymphocytes in NPC samples semi-quantitatively. CD25+/FOXP3+ T-cells were highly prevalent in primary NPCs, suggesting the presence of the immunosuppressive Tregs in tumor microenvironments. The low abundance of CD4+ T-cells, and the positive correlation between FOXP3 and CD8 staining in NPC samples imply that CD8+FOXP3+ Tregs may be present and play role in the suppression of anti-tumor immune response in NPC patients. The involvement of chemokine in the migration of tumor-infiltrating lymphocytes was studied. Chemokine ligand 20 (CCL20) was overexpressed in all EBV-positive NPC cell lines and xenografts compared to EBV-negative NPC, and immortalized normal nasopharynx epithelial cell lines. The presence of CCL20 was also found in primary tumors but not in normal epithelium. Furthermore, the ability of LMP1 to upregulate CCL20 expression in epithelial cells indicates that EBV may induce the production of chemokine involved in lymphocyte migration. / Epstein-Barr virus (EBV) is invariably associated with the development of nasopharyngeal carcinoma (NPC). Although the association of EBV and cancer has been reported for about four decades, it is still not clear how EBV latent infection contributes to the transformation of nasopharyngeal epithelial cells. The aims of this study are to identify EBV-regulated cellular genes and pathways and to determine the potential role of EBV in the modulation of anti-tumor immune responses in NPC. / In summary, EBV plays critical roles in the development of NPC by regulation of multiple cellular genes and pathways such as the Notch signaling cascade, and modulation of anti-tumor immune responses through the induction of chemokine important in migration of immune cells. / Notch signaling pathway functions in diverse cellular processes such as proliferation, apoptosis, adhesion, and epithelial to mesenchymal transition. In the current study, aberrant expression of activated Notch1 receptor (NICD), Notch ligand (Jagged1), negative regulator of Notch ( NUMB) and Notch downstream effector (HEY1) was detected in NPC cell lines and xenografts. Overexpression of NICD, Jagged1 and HEY1 proteins was also commonly found in primary tumors of NPC. / Transfection of Jagged1 to normal nasopharynx epithelial cells resulted in increased cell proliferation. Moreover, EBERs, which is abundantly expressed in EBV-positive NPC tumors, was capable of inducing the expression of Jagged1 in epithelial cells. The current data shows that Notch signaling pathway is aberrantly activated by the deregulated expression of multiple Notch components in NPC. The induction of Jagged1 by EBERs also implies the potential role of EBV in the activation of Notch signaling cascade in NPC. / Using high-density oligonucleotide microarray, expression profiles of EBV-infected NPC cell lines, HK1+EBV and HONE1+EBV, and their uninfected counterparts, HK1 and HONE, were generated. From the microarray results, six EBV-upregulated (JDP2, IL8, ATP6V0E2L, PLAP, PIK3C2B and AKR1B10 ) and three EBV-downregulated genes (BACE2, PADI3 and MMP1) were identified in both HK1 and HONE1 cells upon EBV latent infection. One hundred and thirty-eight and seventy-six genes were also found to be differentially modulated by EBV in HK1 and HONE1 cells, respectively. This study shows that cellular genes involved in wide range of biological processes and cellular functions are differentially regulated by EBV, which suggest that EBV modulates multiple pathways and processes during NPC tumorigenesis. / Hui, Wai Ying. / Adviser: Kw Lo. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 0806. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 166-204). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / School code: 1307.
22

Alterations in epstein-barr virus gene expression after treatment with demethylating agents.

January 2001 (has links)
Heung May-sze. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references. / Abstracts in English and Chinese. / Title Page --- p.i / Acknowledgement --- p.ii / Table of Contents --- p.iii / List of Abbreviations --- p.vi / List of Figures --- p.viii / List of Tables --- p.xii / Abstract --- p.xiv / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Epstein-Barr Virus --- p.1-1 / Chapter 1.1.1 --- Virus structure --- p.1-1 / Chapter 1.1.2 --- Genome structure --- p.1-1 / Chapter 1.1.3 --- Nomenclature for EBV open reading frames --- p.1-2 / Chapter 1.1.4 --- Biology of EBV --- p.1-2 / Chapter 1.1.5 --- EBV latency --- p.1-7 / Chapter 1.1.6 --- EBV latent gene promoters --- p.1-8 / Chapter 1.2 --- EBV Infection and Its Persisence --- p.1-9 / Chapter 1.3 --- DNA Methylation --- p.1-17 / Chapter 1.3.1 --- Aberrant CpG island methylation in cancer --- p.1-18 / Chapter 1.3.2 --- DNA methylation and EBV --- p.1-19 / Chapter 1.4 --- Demethylating Agents --- p.1-21 / Chapter 1.5 --- Aims of the Study --- p.1-23 / Chapter Chapter 2 --- EBV Latency Patterns / Chapter 2.1 --- Introduction --- p.2-1 / Chapter 2.2 --- Materials and Methods --- p.2-1 / Chapter 2.2.1 --- Cell line culture --- p.2-1 / Chapter 2.2.2 --- NPC biopsies culture --- p.2-2 / Chapter 2.2.3 --- RNA extraction --- p.2-3 / Chapter 2.2.4 --- RNA quantification --- p.2-4 / Chapter 2.2.5 --- Deoxyribonuclease I treatment for NPC biopsies --- p.2-5 / Chapter 2.2.6 --- Reverse transcriptase-polymerase chain reaction --- p.2-5 / Chapter 2.2.7 --- Gel Electrophoresis --- p.2-10 / Chapter 2.3 --- Results --- p.2-11 / Chapter 2.3.1 --- Burkitt' s lymphoma and lymphoblastoid cell lines --- p.2-11 / Chapter 2.3.2 --- Nasopharyngeal carcinoma biopsies --- p.2-11 / Chapter 2.4 --- Discussion --- p.2-19 / Chapter Chapter 3 --- Treatment with Demethylating Agents on Rael / Chapter 3.1 --- Introduction --- p.3-1 / Chapter 3.2 --- Materials and Methods --- p.3-2 / Chapter 3.2.1 --- Rael cell line culture --- p.3-2 / Chapter 3.2.2 --- Drug treatment --- p.3-2 / Chapter 3.2.3 --- Viability staining --- p.3-2 / Chapter 3.2.4 --- Statistical analysis --- p.3-3 / Chapter 3.2.5 --- RNA extraction and quantification --- p.3-3 / Chapter 3.2.6 --- RT-PCR and gel electrophoresis --- p.3-3 / Chapter 3.2.7 --- DIG oligonucleotide 3'-end labeling --- p.3-3 / Chapter 3.2.8 --- Southern blot --- p.3-10 / Chapter 3.3 --- Results --- p.3-13 / Chapter 3.3.1 --- 5-azacytidine --- p.3-13 / Chapter 3.3.2 --- 5-aza-2-deoxycytidine --- p.3-26 / Chapter 3.4 --- Discussion --- p.3-39 / Chapter Chapter 4 --- Treatment with Demethylating Agents on NPC Biopsies / Chapter 4.1 --- Introduction --- p.4-1 / Chapter 4.2 --- Materials and Methods --- p.4-2 / Chapter 4.2.1 --- NPC biopsy culture --- p.4-2 / Chapter 4.2.2 --- Drug treatment --- p.4-2 / Chapter 4.2.3 --- RNA extraction and quantification --- p.4-2 / Chapter 4.2.4 --- DNase I treatment for NPC biopsies --- p.4-2 / Chapter 4.2.5 --- RT-PCR and gel electrophoresis --- p.4-2 / Chapter 4.3 --- Results --- p.4-3 / Chapter 4.4 --- Discussion --- p.4-3 / Chapter Chapter 5 --- Conclusion --- p.5-1 / Reference --- p.R-1 / Appendix --- p.A-l
23

Investigação da presença e da influência do Epstein-Barr vírus na severidade da papilomatose laríngea /

Costa, Victor Bernardes Barroso. January 2019 (has links)
Orientador: Estela Kaminagakura / Coorientadora: Patrícia Pimentel de Barros / Banca: Ana Sueli Rodrigues Cavalcant / Banca: Luana Marotta Reis de Vasconcellos / Banca: Lia Mizobe Ono / Banca: Luciana Yamamoto de Almeida / Resumo: 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. / Doutor
24

Epigenetics in nasopharyngeal carcinoma /

Sun, Di, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.
25

EBV membrane protein LMP2A interactions with ubiquitin ligases and signaling scaffold /

Matskova, Liudmila V., January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 3 uppsatser.
26

Detecção e quantificação do virus Epstein-Barr pela reação em cadeia da polimerase em tempo real (real time PCR) em pacientes transplantados de celulas hematopoeticas e coinfecção com o citomegalovirus / Detection and quantification of Epstein-Barr virus by real time polymerase chain reaction in hematopoietic stem cell transplantation patients and coinfection with cytomegalovirus

Pasquotto, Juliana 30 January 2008 (has links)
Orientador: Sandra Cecilia Botelho Costa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-11T03:22:40Z (GMT). No. of bitstreams: 1 Pasquotto_Juliana_M.pdf: 2465167 bytes, checksum: dcd2cc122494bab62d8ab495927b1f0e (MD5) Previous issue date: 2008 / Resumo: O Vírus Epstein-Barr (EBV) e o Citomegalovírus (HCMV) são membros da família Herpesvírus. São encontrados em aproximadamente 90% dos indivíduos em idade adulta. A infecção ocorre, geralmente, na infância e é assintomática na maioria dos casos, persistindo de forma latente durante toda a vida do indivíduo. A transmissão destes vírus ocorre principalmente pela saliva, sangue e órgãos transplantados. O EBV está relacionado com a mononucleose infecciosa, doença linfoproliferativa (PTLD), leucemia de células pilosas em pacientes com imunodeficiência congênita ou adquirida e doença de Hodgkin. O risco de um paciente transplantado desenvolver linfoma é 28 a 50 vezes maior do que os indivíduos da população geral. Um dos fatores de risco para o desenvolvimento da PTLD são a variedade e intensidade da imunossupressão utilizada no paciente pós-transplante, idade do receptor e sorologia viral (EBV, CMV). Dependendo da idade do receptor, do tipo de transplante e dos fatores de risco, a prevalência da PTLD pode variar de 0.5% a 22%. Em transplantados pediátricos renais a prevalência chega a atingir 37%. A principal medida terapêutica para o controle da PTLD é a diminuição ou mesmo a retirada total da imunossupressão. Portanto a rejeição do enxerto se torna um problema bastante comum, que compromete a qualidade e/ou expectativa de vida dos pacientes. A introdução de testes laboratoriais rápidos e precoces permite aos clínicos detectar a replicação viral do EBV e diagnosticar, consequentemente, a infecção ativa antes do início da doença. Isso proporciona a oportunidade de iniciar o tratamento específico precocemente. Foram estudadas amostras de sangue e soro de 46 pacientes submetidos a transplantes de células hematopoéticas, acompanhados no Serviço de Transplante de Medula Óssea (STMO) do Hospital das Clínicas da UNICAMP/HEMOCENTRO. Trabalhamos no estudo para diagnosticar a infecção ativa e quantificar a carga viral do vírus Epstein-Barr (EBV) em pacientes transplantados de células hematopoéticas. Relacionar infecção ativa do vírus Epstein-Barr com o Citomegalovírus (CMV) e verificar a incidência da Doença linfoproliferativa e a Doença do enxerto contra o hospedeiro (GVHD) nos pacientes estudados. Diagnosticamos infecção ativa pelo EBV em 22 (47,8%) pacientes que apresentaram uma carga viral muito baixa (média de 29 cópias/ul). Co-infecção entre EBV e CMV ocorreu em 15/46 pacientes (32,6%). Doença por CMV ocorreu em 7/46 (15,2%) pacientes no trato gastrintestinal. Todos estes doentes apresentaram infecção ativa pelo CMV e 4/7 (57%) apresentaram infecção ativa pelo EBV. Um destes pacientes foi a óbito por doença por CMV. Verificamos que nenhum dos pacientes apresentou doença linfoproliferativa relacionada ao EBV. Os casos de co-infecção ativa EBV+CMV em relação à ocorrência de GVHD foram estatisticamente significantes (p=0.001). Concluímos que a infecção pelo CMV ainda é a maior causa de morbidade e mortalidade nos pacientes após o transplante. A qPCR é uma ferramenta útil para verificar os pacientes que reativaram pelo EBV após o transplante e pode auxiliar na prevenção da doença linfoproliferativa causada pelo EBV juntamente com a identificação dos fatores de risco associados. Verificamos a ocorrência e significância do GVHD e infecção ativa pelo CMV, mas não observamos esses mesmos resultados comparados ao EBV / Abstract: Epstein-Barr Virus (EBV) and Cytomegalovirus (CMV) are members of herpesvirus family. They are found in approximately 90% of the individuals in adult age. The infection generally occurs subclinicaly during the childhood in the major of the cases persisting in latent form during all the life of the individual. The transmission of these viruses occurs mainly for the saliva, blood and transplanted organs. EBV is related with mononucleose infectious, lynfoproliferative disease (PTLD), leukemia of hair cells in patients with congenital or acquired immunodeficiency and Hodgkin¿s disease. The risk of a transplanted patient to develop linfoma is 28 to 50 % more than other individuals of the general population. One of the risk factor for the development of the PTLD is the variety and intensity of the imunossupression used in the patient after-transplant, age of the recipient and viral serology (EBV, CMV). Depending on the age of the recipient, the type of transplant and the risk factor, the prevalence of the PTLD can vary of 0.5% 22%. In renal pediatric transplantation, the prevalence can arrives to reach 37%. The main therapeutical measure for the control of the PTLD is the reduction or total withdrawal of the imunossupression. Therefore the lost of graft is a common problem, that compromises the quality and/or life expectancy of the patients. The introduction of early and rapid laboratorial tests can permit to the physicians to detect the viral response and detect the active EBV infection before the disease. This provides the chance to initiate the specific treatment. We studied samples of blood and serum of 46 patients submitted to hematopoietic stem cell transplantation at the Bone Marrow Transplant unit of the University Hospital of the UNICAMP/HEMOCENTRO. We worked in the study to diagnosis the active infection and quantify the viral load of the Epstein-Barr virus (EBV) in transplanted patients of hematopoetic stem cells, to relate active EBV infection with active CMV infection and to verify the incidence of the lynfoproliferative disease and graft versus host disease (GVHD) in the studied patients. Active EBV infection detected by Real-Time PCR occurred in 22 patients (47,8%). The viral load found was very low (range 29 copies/ul). Co-infection between EBV and CMV occurred in 15/46 patients (32,6%). CMV disease occurred in 7/46 (15,2%) patients in the gastrointestinal tract. All these patients had active CMV infection and 4/7 patients (57%) had active EBV infection. One of these patients died by CMV disease. No patient presented lymphoproliferative disease related to the EBV. The cases of active EBV and CMV (co-infection) infection in relation to the occurrence of GVHD had been statisticaly significant (p=0.001). We conclude that the active CMV infection is already the most cause of morbidity and mortality of the patients after the transplant. The qPCR is a useful tool to verify the patients who had active EBV infection after the transplant and the identification of the risk factors associates prevention the development of the lymfoproliferative disease caused by the EBV. We verify the occurrence and significance of the GVHD and active CMV infection, but we do not observe these same results related to the EBV / Mestrado / Mestre em Farmacologia
27

Associação do Epstein-Barr vírus com os anticorpos anti-CCP, os alelos do epítopo compartilhado e o tabagismo em pacientes brasileiros com artrite reumatoide / Association of Epstein-Barr virus with anti-CCP antibodies, the shared epitope alleles and smoking in Brazilian patients with rheumatoid arthritis

Yazbek, Michel Alexandre, 1978- 09 May 2014 (has links)
Orientadores: Manoel Barros Bértolo, Lilian Tereza Lavras Costallat / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T07:51:21Z (GMT). No. of bitstreams: 1 Yazbek_MichelAlexandre_D.pdf: 3193834 bytes, checksum: 4155cea9577385c29405700add4864ef (MD5) Previous issue date: 2014 / Resumo: A etiopatogenia da Artrite Reumatoide (AR) envolve fatores genéticos, imunológicos e ambientais que interagem entre si. Os principais fatores de risco estudados são a presença dos alelos do epítopo compartilhado (shared epitope- SE), dos anticorpos anti-peptídeos cíclicos citrulinados (anti-CCP) e do tabagismo. Há evidências que o Epstein-Barr vírus (EBV), ao interagir com esses fatores de risco, possa causar uma resposta imune anômala em indivíduos susceptíveis. Essas interações também podem contribuir para o desenvolvimento da AR. O objetivo principal desse estudo é estabelecer se há uma associação entre o EBV com os alelos do SE, os anticorpos anti-CCP e o tabagismo em pacientes brasileiros com AR. Os objetivos secundários são: avaliar a correlação entre os alelos do SE, os anticorpos anti-CCP e o tabagismo; detectar a exposição ao EBV e quantificar sua carga viral e estimar o risco de cada fator estudado para o desenvolvimento da AR nessa casuística. Nesse estudo caso-controle, incluímos 140 pacientes brasileiros com AR e 143 controles saudáveis; pareados por idade, sexo e etnia. Foi feita uma caracterização clínico-laboratorial da casuística. Foram realizadas a genotipagem para identificar os alelos do SE, a determinação dos anticorpos anti-CCP pelo método de ELISA e coletada a história de tabagismo de todos os sujeitos da pesquisa. Para avaliar a exposição ao EBV, realizamos a dosagem dos anticorpos anti-Epstein-Barr Nuclear Antigen 1 (anti-EBNA1). Para quantificar a carga viral do EBV, realizamos o método quantitativo da reação em cadeia polimerase em tempo real ou real-time PCR. A análise comparativa entre os grupos mostrou uma positividade significativamente maior para os alelos do SE, anticorpos anti-CCP e tabagismo no grupo de pacientes. A análise dos anticorpos anti-EBNA1 mostrou uma positividade alta, tanto em pacientes como em controles, sem diferença significativa. Entretanto, a quantificação da carga viral pela PCR em tempo real mostrou-se muito maior em pacientes do que em controles (p<0.001). As análises associativas dos anticorpos anti-EBNA1 com os outros fatores estudados não se mostraram significativas; assim como as análises associativas da carga viral do EBV pela PCR em tempo real. A positividade do anti-CCP foi maior em pacientes com os alelos do SE que são tabagistas ou ex-tabagistas (p=0.038). Nas análises de regressão logística, a variável com maior risco para o desenvolvimento da AR foi a positividade dos anticorpos anti-CCP. Apesar dos pacientes com AR apresentarem uma carga viral do EBV aumentada, esse estudo não conseguiu associá-la aos demais fatores de risco estudados. Sugerimos que esses achados possam ocorrer devido a um controle deficitário do EBV em pacientes com AR, mas que não está relacionado aos fatores de risco mais conhecidos da doença. A imunidade celular defeituosa dos pacientes com AR dificulta o controle de uma infecção latente do vírus. Portanto, não é possível estabelecer uma relação causal direta entre o EBV e a AR / Abstract: The pathogenesis of rheumatoid arthritis (RA) involves genetic, immunological and environmental factors. The main risk factors are the presence of the shared epitope alleles (shared epitope- SE), anti-cyclic citrullinated peptide antibodies (Anti-CCP) and smoking. There is evidence that the Epstein-Barr virus (EBV), when interacts with these risk factors, may cause an abnormal immune response in susceptible individuals. These interactions may contribute to the development of RA. The main objective of this study is to establish whether there is an association between EBV and alleles of SE, anti-CCP antibodies and smoking in Brazilian patients with RA. Secondary objectives are the assessment of the correlation between alleles of SE, anti-CCP antibodies and smoking; the detection of EBV; the quantification of EBV viral load and the estimation of the likelihood of each analyzed factor for the development of RA in this sample. In this case-control study, we included 140 Brazilian patients with RA and 143 healthy controls; matched for age, sex and ethnicity. We performed a clinical and laboratory characterization of the sample. Genotyping was performed to identify SE alleles, anti-CCP antibodies were examined by ELISA and smoking information was collected from all subjects. To assess the exposure to EBV, we examined anti-Epstein-Barr Nuclear Antigen 1 (anti-EBNA1) antibodies. To quantify the viral load of EBV, we performed the quantitative method of polymerase chain reaction in real time or real-time PCR. The comparative analysis between groups showed a significantly higher positivity for the alleles of SE, anti-CCP antibodies and smoking in patients. The analysis of anti-EBNA1 antibodies showed a high positivity, both in patients and in controls, with no significant difference. However, the quantification of viral load by real-time PCR proved to be much higher in patients than in controls (p <0.001). Associative analysis of anti-EBNA1 antibodies with other factors studied were not significant; as well as the association analyzes of the EBV viral load by PCR in real time. The positivity of anti-CCP antibodies was higher in patients with SE alleles which are smoker or ex-smoker (p = 0.038). In logistic regression analyzes, the variable with higher risk for RA was the positivity of anti-CCP antibodies. Although patients with RA present an increased EBV viral load, this study did not link EBV to the other risk factors studied. We suggest that these findings may be due to a deficient control of EBV in RA patients, which is unrelated to the better-known disease risk factors. Defective cellular immunity of patients with RA complicates the control of latent virus infection. Therefore it is not possible to establish a direct causal relationship between EBV and RA / Doutorado / Clinica Medica / Doutor em Clínica Médica
28

The Cellular Immune Response to Epstein-Barr Virus during Active Infectious Mononucleosis: a Thesis

Tomkinson, Blake E. 01 June 1988 (has links)
Epstein-Barr virus (EBV) induced infectious mononucleosis (IM) is characterized by the activation and expansion of T lymphocytes and the induction of cytotoxic responses able to mediate the lysis of EBV-uninfected, allogeneic MHC mismatched and EBV-infected autologous target cells. Freshly isolated peripheral blood mononuclear cells (PBMC) were used to examine the nature of these cellular immune responses. Activated lymphocytes, as identified by HLA-DR expression, associated with EBV induced IM were shown to be a heterogeneous population containing significantly elevated cytotoxic/suppressor (CD8+) T cells, helper/inducer (CD4+) T cells and natural killer (NK, CD16+) cells. CD8+ T cells were the primary activated population, representing 24% of the total lymphocyte population and 60-70% of the CD8+ T cell population. The activated CD4+ T cells and natural killer (NK) cells accounted for 7% and 4% of the total lymphocyte population, respectively. Analysis of serum soluble interleukin 2 receptors (IL-2R) and CD8 molecules demonstrated significantly (p<0.001) elevated levels in the sera of IM patients compared with normal controls. These elevated levels of serum IL-2R am CD8 molecules correlated, (r=0. 67 and r=0.82, respectively) with increased percentages of CD8/HLA-DR positive T cells (i.e., activated CD8 T cells). Increased levels of soluble cell surface molecules peaked during the acute phase and normalized as the patients progressed toward convalescence. Individual patients demonstrated strong correlations between the percentage of CD8/HLA-DR positive cells and soluble CD8 levels. The functional significance of the serum IL-2R and CD8 molecules is presently unknown. However, the strong correlative data between serum CD8, and to a lesser extent IL-2R, and CD8 T cell activation suggests that serum CD8 levels may provide a sensitive measure of CD8 T cell activation in systemic infections. The ability of freshly isolated acute IM PBMC to lyse allogeneic, EBV-infected lymphoblastoid cell lines (LCL), demonstrated the ability of acute IM effector cells to lyse MHC mismatched target cells. Effector cells from acute IM patients lysed allogeneic DM-LCL and AF-LCL target cells by 34% (n=7) and 23% (n=6), respectively, compared with 4% (n=5) and 0% (n=5), respectively, for normal controls. MAb-dependent complement depletion of CD3+ or CD8+ cells with anti-CD3 and anti-CD8 mAb decreased the non-MHC restricted cytolysis of LCL by 96% and 89%, respectively. In contrast, complement depletion with NK-cell specific mAbs Leu 11b and NKH-1, resulted in only a slight decrease (<35%) in the lysis of these LCL (46%). Depletion with anti-HLA-DR also significantly (p<0.001) decreased the lysis of LCL. Depletions with anti-CD4 demonstrated no decrease in LCL-lysis. MAbs OKT3 and OKT8 inhibited the non-MHC restricted cytolysis by 87% and 82%, respectively. We interpret these results as evidence that, 1) lysis of allogeneic cells is mediated primarily by CD3+, CD8+, HLA-DR+, cytotoxic T lymphocytes (CTL); and 2) these acute IM cytotoxic T cells utilize the T cell receptor and the CD8 antigen as an accessory molecule. An active role for target cell MHC class I molecules in the recognition and subsequent lysis of target cells is supported by a number of observations: 1) the MHC class I reactive mAbs W6/32 and BBM.1 significantly (p<0.05) inhibited the lysis of 63463-LCL by 65% and 57%, respectively; 2) acute IM effector T cells did not lyse the MHC class I negative Daudi cell line; 3) allogeneic MHC class I matched LCL mediated strong competitive inhibition (72% at 10:1 competitor to target cell ratio) vs 29% competitive inhibition for an allogeneic MHC class I mismatched LCL; and 4) NK-cell depleted effector cells from one patient mediated preferential lysis of the K562 cell line expressing MHC class I. HLA-A2 molecules. We interpret these results as evidence that target cell MHC class I molecules (or associated determinants) are the target antigen(s) for the allogeneic MHC cytotoxic response. The role of EBV in this acute allogeneic response was examined using target cell lines devoid of EBV genome. Acute IM CTL mediated lysis of the allogeneic HSB-2 T cell line (45%), and allogeneic HTLV-I transformed T cell lines (16%). The lysis of the HSB-2 T cell line was inhibited by anti-OKT3 (58% inhibition), W6/32 (53%) and BBM.1 (42%). Similarily, lysis of HTLV-I T cell lines was inhibited by W6/32 (69% inhibition), BBM.1 (69%) and OKT3 (38%). These data demonstrate that EBV antigenic expression is not required for allogeneic recognition and subsequent lysis of these allogeneic target cells. Effector cells from acute IM patients (n=5) were able to lyse their autologous EBV-infected LCL (mean lysis=21%), but were unable to lyse the EBV-uninfected autologous HTLV-I T cell line. These same effectors, however, were able to mediate lysis of both allogeneic B cell lines (21% lysis) and allogeneic T cell lines (8% lysis). These data are consistent with the observations by Strang et al. (1987a), who recently cloned virus specific/MHC-restricted CTL cloned from acute IM PBMC. These virus specific/MHC-restricted T cells presumably mediate the lysis of the autologous EBV-transformed B cell lines but not the autologous EBV-uninfected T cell lines. Whether the CTL which lyse the autologous EBV-transformed LCL are also responsible for the observed allogeneic reactivity was examined with cold target competition using autologous and allogeneic LCL. Lysis of autologous LCL was inhibited only by autologous competitor cells (64% inhibition compared with 24% for allogeneic LCL). Likewise, lysis of the allogeneic LCL was inhibited only by the allogeneic competitor cells (85% inhibition compared with 30% for autologous LCL). These data demonstrated no competition between allogeneic and autologous LCL and therefore support the concept that lysis of autologous LCL and allogeneic target cells is mediated by distinct effector populations. These data help us to understand the unusual immune response observed during acute IM. The strong allogeneic cytotoxic response is thought to represent polyclonal CD8 T cell activities induced by EBV-infected and transformed B cells which circulate in vivo. In addition, a population of CD8 CTL exist which mediate the lysis of autologous EBV-transformed B cells. These CTL likely represent virus-specific/MHC-restricted CTL and presumably play a major role in the control of EBV infections. The role, if any, of the markedly expanded alloreactive CTL population in the elimination of EBV infected and transformed B cells remains to be clarified.
29

Role of prolyl isomerase PIN1 on tumorigenesis of nasopharyngeal carcinoma. / CUHK electronic theses & dissertations collection

January 2013 (has links)
Xu, Meng. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 112-129). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
30

Deregulated NF-κB signalling pathways in EBV-positive nasopharyngeal carcinoma. / Deregulated NF-kappa B signalling pathways in Epstein-Barr virus-positive nasopharyngeal carcinoma / Deregulated NF-kB signalling pathways in EBV-positive nasopharyngeal carcinoma / EB病毒陽性鼻咽癌的NF-кB信號通路失調 / EB bing du yang xing bi yan ai de NF-кB xin hao tong lu shi tiao

January 2011 (has links)
Lou, Pak Kin. / Thesis (M.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 136-170). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.v / Table of Contents --- p.vi / List of Figures --- p.x / List of Tables --- p.xiii / List of Publications --- p.xv / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1. --- Aims of Study --- p.1 / Chapter 1.2. --- Literature Review --- p.2 / Chapter 1.2.1. --- Nasopharyngeal Carcinoma --- p.2 / Chapter 1.2.1.1. --- Overview --- p.2 / Chapter 1.2.1.2. --- Histopathology --- p.2 / Chapter 1.2.1.3. --- Epidemiology --- p.3 / Chapter 1.2.1.4. --- Etiology --- p.5 / Chapter 1.2.1.4.1. --- Epstein-Barr Virus (EBV) Latent Infection --- p.5 / Chapter 1.2.1.4.2. --- Environmental Factors --- p.5 / Chapter 1.2.1.4.3. --- Genetic Factors --- p.6 / Chapter 1.2.1.5. --- Molecular Pathogenesis --- p.7 / Chapter 1.2.1.5.1. --- Chromosomal Alterations --- p.7 / Chapter 1.2.1.5.2. --- NPC-associated Tumour Suppressor Genes --- p.7 / Chapter 1.2.1.5.3. --- NPC-associated Oncogenes --- p.8 / Chapter 1.2.2. --- Epstein-Barr Virus --- p.9 / Chapter 1.2.2.1. --- Overview --- p.9 / Chapter 1.2.2.2. --- Lytic and Latent Infection of EBV --- p.9 / Chapter 1.2.2.3. --- EBV Latency Programs and Associated --- p.10 / Malignancies --- p.11 / Chapter 1.2.2.4. --- The Role of EBV in NPC --- p.12 / Chapter 1.2.3. --- NF-kB Signalling Pathways --- p.12 / Chapter 1.2.3.1. --- Overview --- p.12 / Chapter 1.2.3.2. --- Pathway Components --- p.12 / Chapter 1.2.3.2.1. --- NF-kB Subunits --- p.16 / Chapter 1.2.3.2.2. --- Inhibitors of kB (IkBs) --- p.16 / Chapter 1.2.3.2.3. --- IkB Kinases (IKKs) --- p.17 / Chapter 1.2.3.3. --- NF-kB Activation and Signalling --- p.17 / Chapter 1.2.3.3.1. --- The Canonical Pathway --- p.18 / Chapter 1.2.3.3.2. --- The Non-canonical Pathway --- p.18 / Chapter 1.2.3.3.3. --- Physiological Functions of NF-kB --- p.19 / Chapter 1.2.3.4. --- NF-kB Signalling and Tumourigenesis --- p.20 / Chapter 1.2.3.4.1. --- Oncogenic Activation of NF-kB in Hematological Malignancies --- p.20 / Chapter 1.2.3.4.2. --- Oncogenic Activation of NF-kB in Solid and Epithelial Tumours --- p.22 / Chapter Chapter 2 --- Material and Methods --- p.22 / Chapter 2.1. --- Tumour Specimens --- p.24 / Chapter 2.2. --- NPC Tumour Lines and Immortalized NP Cell Lines --- p.24 / Chapter 2.2.1. --- Cell Lines --- p.24 / Chapter 2.2.2. --- Xenografts --- p.27 / Chapter 2.3. --- DNA Sequence Analysis --- p.27 / Chapter 2.3.1. --- Genomic DNA Extraction --- p.27 / Chapter 2.3.2. --- Polymerase Chain Reaction (PCR) --- p.28 / Chapter 2.3.3. --- DNA Sequencing --- p.32 / Chapter 2.4. --- RNA Expression Analysis --- p.32 / Chapter 2.4.1. --- Total RNA Extraction and Reverse Transcription --- p.33 / Chapter 2.4.2. --- Quantitative Real-time Polymerase Chain Reaction (QRT-PCR) --- p.35 / Chapter 2.5. --- Protein Expression Analysis --- p.35 / Chapter 2.5.1. --- Total Protein Extraction --- p.35 / Chapter 2.5.2. --- Nuclear and Cytoplasmic Protein Isolation --- p.36 / Chapter 2.5.3. --- Western Blotting --- p.39 / Chapter 2.6. --- Immunohistochemical Staining --- p.41 / Chapter 2.7. --- Statistical Analysis --- p.41 / Chapter 2.8. --- Immunoprecipitation --- p.43 / Chapter 2.9. --- Electrophoretic Mobility Shift Assay (EMSA) and Supershift Assay --- p.44 / Chapter 2.10. --- Enzyme-Linked Immunosorbent Assay (ELISA) --- p.45 / Chapter 2.11. --- Plasmid Preparation --- p.45 / Chapter 2.11.1. --- Plasmids --- p.45 / Chapter 2.11.2. --- Bacterial Transformation and Plasmid DNA Extraction --- p.46 / Chapter 2.12. --- Transfections --- p.46 / Chapter 2.12.1. --- Transient Transfection --- p.46 / Chapter 2.12.2. --- Stable Transfection --- p.47 / Chapter 2.13. --- Immunofluorescence --- p.47 / Chapter 2.14. --- Cell Proliferation and Viability Analysis --- p.47 / Chapter 2.15. --- Small Interfering RNA (siRNA) Knockdown --- p.49 / Chapter 2.16. --- Expression Microarray --- p.49 / Chapter 2.16.1. --- Agilent Oligonucleotide Microarray --- p.50 / Chapter 2.16.2. --- Data Analysis --- p.51 / Chapter Chapter 3 --- Activation of NF-kB Signals in NPC --- p.51 / Chapter 3.1. --- Introduction --- p.52 / Chapter 3.2. --- Results --- p.52 / Chapter 3.2.1. --- Expression Pattern of NF-kB Subunits in NPC Tumour Lines --- p.55 / Chapter 3.2.2. --- Distinct NF-kB Complexes in NPC Tumour Lines --- p.60 / Chapter 3.2.3. --- Expression of NF-kB Subunits in NPC Primary Tumours --- p.67 / Chapter 3.3. --- Discussion / Chapter Chapter 4 --- Alterations of NF-kB Components in NPC --- p.71 / Chapter 4.1. --- Introduction --- p.72 / Chapter 4.2. --- Results --- p.72 / Chapter 4.2.1. --- Homozygous Deletion of IicBa and TRAF3 in NPC Tumour Lines --- p.76 / Chapter 4.2.2. --- Mutation of TRAF2 and A20 in NPC Tumour Lines / Chapter 4.2.3. --- Aberrant Expression of Multiple NF-kB Signalling Components in NPC Tumour Lines --- p.80 / Chapter 4.2.4. --- Expression of NF-kB Signalling Components in NPC --- p.85 / Primary Tumour --- p.92 / Chapter 4.3. --- Discussion --- p.99 / Chapter Chapter 5 --- Identification of Downstream Targets for NPC-associated NF-kB Signalling --- p.99 / Chapter 0.1. --- Introduction --- p.99 / Chapter 0.2. --- Results --- p.100 / Chapter 0.2.1. --- Target Genes Modulated by p50 --- p.100 / Chapter 0.2.2. --- Functional Annotation of p50 Target Genes --- p.105 / Chapter 0.2.3. --- Target Genes Modulated by RelB --- p.105 / Chapter 0.2.4. --- Functional Annotation of RelB Target Genes --- p.105 / Chapter 0.2.5. --- Functional Annotation of Genes Modulated by both p50 and RelB --- p.111 / Chapter 0.3. --- Discussion --- p.118 / Chapter Chapter 6 --- Functional Role of TRAF3 Inactivation in NPC --- p.118 / Chapter 0.1. --- Introduction --- p.118 / Chapter 0.2. --- Results --- p.118 / Chapter 0.2.1. --- Effect of TRAF3 Restoration on NF-kB Activity --- p.119 / Chapter 0.2.2. --- Effect of TRAF3 Expression on Cell Proliferation --- p.123 / Chapter 0.2.3. --- TRAF3 Expression Modulates Interferon Transcription in NPC Cells --- p.128 / Chapter 0.3. --- Discussion / Chapter Chapter 7 --- General Discussion --- p.132 / Chapter Chapter 8 --- Conclusion / Chapter Chapter 9 --- References / Appendix --- p.136

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