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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.
141

Infectious agents and gastric cancers. / CUHK electronic theses & dissertations collection / Digital dissertation consortium

January 2000 (has links)
Wing Y. Chan. / "March 2000." / Thesis (M.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references. / 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 Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
142

Thermodynamic and structural analysis of the interactions between Epstein-Barr virus transcription factors and the host targeting factor RBP-Jkappa

Simmons, Robert January 2018 (has links)
No description available.
143

Elispot assay of HLA class I restricted EBV epitope choices in Hong Kong donors.

January 2004 (has links)
Xu Xuequn. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 100-125). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Epstein-Barr (EBV) Virus --- p.1 / Chapter 1.1.1 --- Virus Structure and Genome Structure --- p.1 / Chapter 1.1.2 --- Virus Types --- p.2 / Chapter 1.2 --- EBV Infection and malignancies --- p.3 / Chapter 1.2.1 --- In Vitro Infection --- p.3 / Chapter 1.2.2 --- Infection in the Natural Host --- p.8 / Chapter 1.2.3 --- Malignancies Associated with EBV --- p.11 / Chapter 1.3 --- T Cell-Mediated Immune Response to EBV --- p.16 / Chapter 1.3.1 --- The Pathway of Cell-Mediated Immune Response in Viral Infection --- p.16 / Chapter 1.3.2 --- Cell-Mediated Immune Response to EBV --- p.18 / Chapter 1.3.3 --- The Feature of CTLs Response to EBV --- p.20 / Chapter 1.4 --- CTLs to EBV Relevant MalignancieśؤApplications and Challenges --- p.21 / Chapter 1.5 --- HLA Polymorphisms and Strategy of Epitope-Based CTLs Therapy --- p.24 / Chapter 1.6 --- The Effect of HLA Polymorphism on EBV-Specific CTL Epitope Choice in Southern Chinese --- p.27 / Chapter 1.7 --- ELISPOT Assay 226}0ؤ Detection of CTLs Response --- p.32 / Chapter 1.8 --- Aim of This Study --- p.37 / Chapter Chapter 2: --- Material and Methods: --- p.39 / Chapter 2.1 --- Peptides --- p.39 / Chapter 2.2 --- PBMCs Preparations --- p.43 / Chapter 2.3 --- PBMC Counting and Cells Dilution --- p.43 / Chapter 2.4 --- Elispot Assay --- p.44 / Chapter 2.5 --- Counting the Spots --- p.45 / Chapter 2.6 --- Spots Forming Cells (SFC/106) and Positive Standard --- p.46 / Chapter Chapter 3: --- Results --- p.47 / Chapter 3.1 --- Validation of ELISPOT assay methodology --- p.47 / Chapter 3.2 --- CTLs Response to Each Epitope in the Population --- p.55 / Chapter 3.2.1 --- Positive Response to A11 Restricted and Mutant Epitopes in the Population --- p.55 / Chapter 3.2.2 --- Positive Frequencies of A2 Restricted Epitopes in the Population --- p.63 / Chapter 3.2.3 --- Positive Frequencies of Other HLA Allele Restriction Peptides --- p.70 / Chapter 3.3 --- CTLs Response Frequencies Categorized by Proteins --- p.74 / Chapter 3.3.1 --- "CTLs Response to LMP1, LMP2, EBNA1 Epitopes" --- p.74 / Chapter 3.3.2 --- "CTLs Response to EBNA2, EBNA-LP Epitopes, EBNA3 Epitopes" --- p.75 / Chapter 3.3.3 --- CTLs Response to LYTIC Epitopes --- p.79 / Chapter 3.4 --- Summary --- p.80 / Chapter Chapter 4: --- Discussion --- p.82 / Chapter 4.1 --- Discussion of A11 Restricted Epitopes --- p.82 / Chapter 4.2 --- Discussion of A2 Restricted Epitopes --- p.86 / Chapter 4.3 --- Discussion of Other HLA Restricted Epitopes --- p.89 / Chapter 4.4 --- "Discussion ofLMPl, LMP2, EBNA1 Epitopes" --- p.92 / Chapter 4.5 --- "Discussion of EBNA2, EBNA3, and EBNA-LP epitopes" --- p.96 / Chapter 4.6 --- Discussion of LYTIC Epitopes --- p.96 / Chapter 4.7 --- Discussion of Summary --- p.98 / Chapter Chapter 5 --- Conclusion --- p.99 / Chapter 6 --- Reference --- p.100 / Chapter 7 --- Appendix --- p.126 / Chapter 7.1 --- "Appendix 1, raw data of Elispot assay on CTLs response to EBV relevant epitopes m Hong Kong donors" --- p.126 / Chapter 7.2 --- "Appendix 2, frequencies from highest cell number wells of the peptides (SFC/106)" --- p.126 / Chapter 7.3 --- "Appendix 3, typical Elispot assay figure " --- p.126
144

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.
145

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
146

Influence of Epstein-Barr Virus on Systemic Lupus Erythematosus Disease Development and the Role of Depression on Disease Progression

Cornaby, Caleb 01 December 2017 (has links)
Systemic Lupus Erythematosus (SLE) is an autoimmune disease affecting 20 to 250 individuals per 100,000 worldwide. Symptomology includes dermatological manifestations such as discoid lesions, acute cutaneous rashes, and oral and nasal ulcers, along with musculoskeletal, pulmonary, and renal complications. Abnormal T and B lymphocyte function and apoptosis, immune complex clearance, complement function, and nucleosome processing are typical of disease pathophysiology. SLE is the result of both environmental and genetic factors, which together create the conditions leading to disease onset and progression. Of these environmental factors, Epstein-Barr virus (EBV) infection is known to cause the genesis of cross-reactive antibodies in SLE prone individuals that can initiate disease activity. Viral infection and modulation of cellular genes is important in understanding the microenvironment that could lead to immune mis-regulation and the inception of lupus in those individuals at risk. During disease development, a variety of variables assist and detract from disease progression and the quality of life experienced by SLE patients. Research into EBV-infected naïve B lymphocytes revealed that EBV modulates the chemotactic receptor EBI2 during viral infection via the BRRF1 viral gene product Na. This likely changes B lymphocyte chemotaxis in secondary tissue in virally infected B cells. Current literature suggests this results in sequestration of cells to peripheral areas of the tissue and mis-regulation of the immune response. It is not uncommon for SLE patients to have neuropsychiatric disorders due to lupus disease activity. With SLE patients being up to 6 times more at risk for depression, recognition and treatment of depression and anxiety have been shown to improve quality of life, pain, and treatment outcomes. Two studies investigate both clinical laboratory and psychosocial assessment variables that we suspect to be correlated with depression in patients with SLE. Univariate and multivariate analysis from our first study identified an array of variables that show strong associations with depression, including: Body Mass Index, Pain, Total Complement, fatigue assessments, and SF-36 scores. The second study found similar associations, but further found that serum IL-10 levels demonstrated a strong correlation with depression in SLE patients. In this final study SLE patients are compared alongside healthy, clinically depressed, and rheumatoid arthritis patients to provide evidence that increased depression in SLE patients is due more to disease pathology than a result of chronic inflammation.
147

Molecular mechanisms of TRAF6 function in signaling pathways of the oncogenic viral mimic of CD40, LMP1

Arcipowski, Kelly Marie 01 December 2012 (has links)
Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) plays important roles in EBV-mediated B cell transformation, development of EBV-associated malignancies, and exacerbation of certain autoimmune conditions. LMP1 functionally mimics tumor necrosis factor receptor (TNFR) superfamily member CD40, but LMP1 signals are amplified and sustained compared to those induced by CD40. CD40 and LMP1 rely on TNFR-associated factors (TRAFs) to mediate signaling, but use TRAFs differently. TRAF6 is important for CD40 signaling, and was implicated in LMP1 signaling in non-B cells. Here, we addressed the hypothesis that TRAF6 is a critical regulator of a subset of LMP1 signals in B cells. We found that TRAF6 was required for LMP1-mediated kinase activation and costimulatory molecule upregulation, and associated with the LMP1 TRAF1/2/3/5 binding site (TBS). Additionally, TRAF6 and the TBS contributed to LMP1-induced autoreactivity and antibody (Ab) production in vivo. Finally, in contrast to CD40, LMP1 required the TRAF6 receptor-binding domain to mediate TRAF6-dependent pathways. Thus, TRAF6 is critical for LMP1 signaling and requires LMP1 interaction to propagate signals. Importantly, TRAF6 associates with LMP1 in a manner distinct from CD40, raising the possibility of disrupting LMP1 functions while leaving normal CD40 signaling intact. We next investigated roles of the kinase TAK1 in TRAF6-dependent LMP1 functions. TAK1 was required for CD40- and LMP1-mediated JNK activation in B cells, leading to IL-6 and Ab production. Understanding mechanisms of CD40 and LMP1 signaling provides important insights into normal regulatory control of CD40 functions and how LMP1-mediated pathogenesis escapes or subverts these regulatory mechanisms. LMP1 itself may be a difficult therapeutic target, because it lacks an extracellular domain and is continually processed from the cell surface. Thus, it is important to elucidate similarities and differences between CD40 and LMP1 signals to identify therapeutic targets to block LMP1-mediated pathogenesis. Comparing and contrasting CD40 and LMP1 also increases our understanding of the critical mechanisms used to regulate normal CD40 signaling.
148

Contributions of Epstein-Barr Nuclear Antigen 1 (EBNA1) to Epithelial Cell Infections

Sivachandran, Nirojini 11 January 2012 (has links)
Epstein-Barr virus (EBV) latent infection is associated with lymphoid and epithelial tumours, including nasopharyngeal carcinoma (NPC) and gastric carcinoma (GC). Since EBNA1 protein is expressed in all EBV tumours, I explored whether EBNA1 alters the cellular environment in ways that would contribute to the development of these epithelial tumours. I have shown that EBNA1 disrupts nuclear bodies (NBs) formed by the PML tumor suppressor and degrades PML proteins in a proteasome dependent manner in NPC and GC cell lines. I have verified the role of EBNA1 in disrupting PML NBs through overexpression and silencing of EBNA1 and shown that EBNA1 alone is sufficient to mediate these effects. Using EBNA1 mutants I found that USP7 and protein kinase CK2 (two enzymes that negatively regulate PML NBs) are important for EBNA1-mediated disruption of PML NBs. Furthermore, I have shown that EBNA1 localizes to PML NBs, and interacts with PML IV, which mediates the enrichment of USP7 and CK2β with PML NBs and increases CK2 phosphorylation of PML proteins, a known prerequisite for PML degradation. Consequently, functions downstream of PML were impaired in the presence of EBNA1. In particular, cells expressing EBNA1 had decreased levels of p53acetylation, p21 and apoptosis in response to DNA damage. Furthermore, DNA repair was markedly impaired in these cells, despite the fact that they survived better after induction of DNA damage than cells lacking EBNA1. In keeping with these observations, immunohistochemistry staining of GC biopsies showed that EBV-positive GC biopsies had lower PML staining compared to EBV-negative samples. These results show that EBNA1 directly affects host cell processes that would be expected to promote malignant transformation. Additionally, I have shown that EBNA1's ability to disrupt PML NBs is important for reactivation of EBV from latency; hence, is required for efficient spread of EBV from host to host.
149

Contributions of Epstein-Barr Nuclear Antigen 1 (EBNA1) to Epithelial Cell Infections

Sivachandran, Nirojini 11 January 2012 (has links)
Epstein-Barr virus (EBV) latent infection is associated with lymphoid and epithelial tumours, including nasopharyngeal carcinoma (NPC) and gastric carcinoma (GC). Since EBNA1 protein is expressed in all EBV tumours, I explored whether EBNA1 alters the cellular environment in ways that would contribute to the development of these epithelial tumours. I have shown that EBNA1 disrupts nuclear bodies (NBs) formed by the PML tumor suppressor and degrades PML proteins in a proteasome dependent manner in NPC and GC cell lines. I have verified the role of EBNA1 in disrupting PML NBs through overexpression and silencing of EBNA1 and shown that EBNA1 alone is sufficient to mediate these effects. Using EBNA1 mutants I found that USP7 and protein kinase CK2 (two enzymes that negatively regulate PML NBs) are important for EBNA1-mediated disruption of PML NBs. Furthermore, I have shown that EBNA1 localizes to PML NBs, and interacts with PML IV, which mediates the enrichment of USP7 and CK2β with PML NBs and increases CK2 phosphorylation of PML proteins, a known prerequisite for PML degradation. Consequently, functions downstream of PML were impaired in the presence of EBNA1. In particular, cells expressing EBNA1 had decreased levels of p53acetylation, p21 and apoptosis in response to DNA damage. Furthermore, DNA repair was markedly impaired in these cells, despite the fact that they survived better after induction of DNA damage than cells lacking EBNA1. In keeping with these observations, immunohistochemistry staining of GC biopsies showed that EBV-positive GC biopsies had lower PML staining compared to EBV-negative samples. These results show that EBNA1 directly affects host cell processes that would be expected to promote malignant transformation. Additionally, I have shown that EBNA1's ability to disrupt PML NBs is important for reactivation of EBV from latency; hence, is required for efficient spread of EBV from host to host.
150

Mecanismes moleculars implicats en la interacció dels receptors cel·lulars herpes simplex virus entry mediator A (HveA) i receptor de complement 2 (CR2, CD21) amb els seus lligands

Sarrias Fornés, Maria Rosa 14 June 2001 (has links)
L'estudi de la utilització del sistema immunològic de l'hoste pels virus com a patògens per al seu propi benefici fou el principal objectiu d'aquest treball. Concretament, en aquest treball de tesis es van analitzar dues espècies d'herpesvirus virulents en humans, l'Herpes Simplex Virus-1 (HSV-1) i l'Epstein Barr Virus (EBV). L'entrada d'ambdós virus a les cèl.lules és mediada per receptors del sistema immunològic. Es va estudiar la interacció dels respectius receptors cel.lulars, Herpes Virus Entry mediator A (HveA), i el receptor de complement 2 (CR2), amb les glicoproteïnes virals que s'hi uneixen, i amb llurs lligands naturals, els quals participen en la defensa de l'hoste. Es va caracteritzar la interacció dels receptors HveA i CR2 amb els seus lligands fent servir proteïnes recombinants o purificades de sèrum; en el cas de HveA ens vam centrar en la localització del lloc d'unió de cada lligand al receptor. En el cas de CR2, es va analitzar la cinètica d'unió dels seus lligands naturals. Per a ambdós receptors, es va analitzar si la unió de la proteïna viral al receptor podria interferir i/o modular-ne la unió dels seus lligands naturals. Els resultats es van analitzar dins del marc de la resposta immunològica de l'hoste mediada pel receptor cel·lular, i en relació al possible paper modificador d'aquesta resposta per part de la proteïna viral. Per a facilitar el nostre estudi sobre HveA, es van cercar nous lligands peptídics d'aquest receptor, utilitzant llibreries aleatòries de pèptids expressades en el fag M13. Es van aïllar dos pèptids, i es va estudiar la seva interacció amb el receptor i la seva capacitat d'inhibir l'entrada del virus a les cèl·lules, és a dir, com a possibles agents terapèutics. / Our goal in the present work was to study the manipulation of the host immune system by an infecting virus to its own benefit. Specifically, we studied two herpes viruses; Herpes Simplex Virus-1 (HSV-1) and Epstein Barr Virus (EBV), which infect humans. Entry of both viruses into the cell is mediated by the interaction of a specific viral surface glycoprotein with two receptors that participate in the host immune response, the Herpes Virus Entry mediator A (HveA), and complement receptor 2 (CR2). We studied the interaction of these receptors with the viral glycoproteins as well as their host ligands. The latter play a role in the immune response of the host. We characterized these interactions by using recombinant as well as serum-purified proteins. Our study of HveA sought to localize the specific binding site of each ligand on the receptor, while that of CR2 consisted in the kinetic analysis of its interaction with its ligands. We also analyzed whether binding of the viral glycoprotein to each receptor would interfere or modulate its interaction with its host ligands. Our results were analyzed in the context of the role of these receptors in the host immune response, and specifically whether the viral proteins studied undermined the host's ability to defend itself from infection. To study the relationship between HveA, its natural ligands, and the viral proteins involved in HSV entry, we also screened two phage-displayed combinatorial peptide libraries for peptide ligands of a recombinant form of HveA. We isolated two peptides, and studied their interaction with HveA as well as their ability to block HSV entry into HveA-bearing cells.

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