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Background: Throughout human history infectious agents such as viruses have been one of the biggest threats to public health. One example of infectious agents that can cause severe malignant conditions in humans is the Epstein-Barr virus (EBV). This virus has been researched for decades but still a lot of its potential malignant functions remain to be elucidated. Autoimmunity, and especially multiple sclerosis (MS), has been strongly associated to EBV infection for a long time but the exact mechanisms behind this relationship are still largely unknown. Aim: The main aim of this study was to investigate the evidence connecting an EBV-specific dysregulated immune response to MS. Methods: This paper is written as a systematic review examining the latest science within the studied field. PubMed was searched for articles published between 2010-2020. Results: In total 15 studies were reviewed. Five out of seven studies found an altered antibody response towards EBV in patients with MS, while one demonstrated somewhat mixed results and one could not support such a pattern. Seven out of eight studies found an altered T cell response towards EBV in MS patients, while one could only support such a trend. Conclusions: This review confirms that there is strong evidence for a dysregulated EBV-specific immune response in MS patients. Evidence for a causal relationship between the failure to control a reactivated EBV infection and the progression of disease is suggestive, but this needs to be confirmed by further studies.

Nasopharyngeal Carcinoma (NPC) as a typical malignancy that occurs in high-incidence areas, e.g. southern China region, including Hong Kong, and it has aroused wide interests for local researchers to study. The Epstein-Barr virus (EBV) was reported as a vital herpes virus for the growth of NPC. Two significant proteins in EBV, namely Epstein-Barr Nuclear Antigen 1 (EBNA1) and latent infection membrane protein 1 (LMP1) are crucial for virus maintenance and EBV-infected cell development, and essential for cell proliferation and differentiation of EBV latent life cycle, respectively. Thus, inhibition of EBNA1 and LMP1 can be regarded as effective and potent therapy on EBV-associated cancers. In this thesis, the conjugation of core-shell structured upconversion nanoparticles (UCNPs) with distinct EBV-specific peptides including EBNA1 and LMP1 targeting peptides to achieve both impressive inhibition on EBV-positive cancers in vitro/in vivo and visualization on EBV-positive cells with responsive upconversion emission signals were investigated. Taking advantage of lanthanide-based UCNPs, their unique photophysical properties offer deep tissue penetration depth, negligible photobleaching and photocytotoxicity, and therefore provides a solid foundation for convincible theranostic studies. Furthermore, desired inhibitory performance was achieved, it was shown that ~50 mg/mL of nanoprobes can inhibit half of EBV-infected cell viability and only 0.25 mg/tumor of nanoprobes dosage via intravenous injection can prohibit 64.7% of growth inhibition of an EBV-positive tumor

Epstein Barr virus (EBV) is a gammaherpesvirus that infects more than 95% of the human population worldwide. EBV latent infection of B cells is associated with a variety of lymphomas and epithelial cancers and accounts for approximately 1% of all human cancers. The EBV genome persists in infected host cells as a chromatinized episome and is subject to chromatin-mediated regulation. Binding of the host insulator protein CTCF to the EBV genome has an established role in maintaining viral latency type, and in other herpesviruses, loss of CTCF binding at specific regions correlates with viral reactivation. CTCF is post-translationally modified by the host enzyme PARP1, which can affect CTCF’s insulator activity, DNA binding capacity, and ability to form chromatin loops. Both PARP1 and CTCF have been implicated in the regulation of EBV latency and lytic reactivation. Here, we show that PARP activity regulates CTCF in type III EBV latency to maintain latency type-specific gene expression. Further, PARP1 supports chromatin looping between the OriP enhancer and other regions throughout the EBV genome. Further, we show that CTCF is not involved in EBV lytic reactivation, although it is known to restrict reactivation in other herpesviruses. Both PARP activity and PARP1 binding function to restrict EBV lytic reactivation in response to physiological lytic induction. Overall, we show that PARP1 has specific functions throughout the EBV genome, and CTCF function is specifically regulated by PARP activity at specific loci. Taken together, we suggest a model in which PARP1 acts as a stress sensor to determine the fate of the virus in the host cell. These data provide a mechanistic understanding of PARP1 function throughout the EBV genome that suggest potential therapeutic application of PARP inhibitors in EBV-associated treatment strategies. We propose two distinct strategies specific to EBV latency type that could target EBV-infected cancer cells beyond the current chemotherapeutic standard-of-care. / Biomedical Sciences

Adoptiver Transfer EBV-spezifischer, polyklonaler T-Zelllinien findet Anwendung bei Prophylaxe und Therapie EBV-assoziierter Erkrankungen. Der Ansatz hat den Nachteil der aufwändigen Herstellung der T-Zelllinien, welche aufgrund der Stimulation mit EBV transformierten B-Zelllinien oft nicht die gewünschten EBV Antigene, sondern immundominante EBV Antigene erkennen. Eine Alternative zum polyklonalen T Zelltransfer stellt die Übertragung EBV-spezifischer T-Zellrezeptoren (TCRs) dar. Dadurch können subdominante EBV Antigene angegangen werden, die von Tumorzellen tatsächlich exprimiert werden. In den hier beschriebenen Arbeiten, verwendeten wir peptidbeladene dendritische Zellen (DCs), um selektiv CD4+ T-Zellen gegen ein Epitop aus dem EBV Protein EBNA2 anzureichern. Es gibt Hinweise darauf, dass DCs sich besonders zur Stimulation von T-Zellen eignen, die subdominante EBV Antigene erkennen. Die TCR Gene eines solchen CD4+ T-Zellklons, sowie zweier CD8+ Klone, wurden in Vektoren kloniert, mit denen die EBV Spezifität der Klone auf andere T-Zellen übertragen werden sollte. Wie bereits zuvor in anderen Laboren beobachtet, waren auch unsere TCR modifizierten T-Zellen zunächst nicht in der Lage, EBV infizierte Zielzellen effektiv zu attackieren. Erst durch Modifikation der Vektorstrategie (2A Peptidlinker als Ersatz für das IRES Element (internal ribosomal entry site)) sowie der TCR Gene (Codon-Optimierung) konnte eine deutlich verbesserte Expression und Funktion der modifizierten T-Zellen erreicht werden. Außerdem hing die Effektivität der modifizierten T-Zellen essentiell von der als Zielzelle verwendeten LCL ab. Die hier beschriebenen Arbeiten zeigen die erfolgreiche Übertragung von TCRs gegen EBV Antigene auf T-Zellen. Die so modifizierten T-Zellen erlangten anti-EBV Aktivität und sprechen daher für die prinzipielle Anwendbarkeit TCR-modifizierter T-Zellen zur Behandlung EBV-assoziierter Erkrankungen. / Adoptive transfer of polyclonal Epstein-Barr-virus (EBV)-specific T cell lines has been used as prophylaxis and therapy in patients with EBV-associated malignancies. This approach, however, is limited by the difficult expansion of polyclonal T cells directed mainly against dominant EBV antigens presented on EBV-transformed B cell lines (LCLs). Isolating EBV-specific T cell receptors (TCRs) for transduction of T cells is an alternative strategy to confer T cell immunity against EBV antigens including subdominant EBV antigens. In this study, we have used peptide-pulsed DCs to selectively expand EBV-specific CD4+ T cell clones against an EBNA2-derived epitope. Data suggested that peptide-pulsed DCs are particularly effective in stimulating T cells specific for subdominant EBV antigens. TCR genes from one of these clones as well as from two CD8+ T cell clones were identified by RACE PCR. TCR alpha and beta chains where then cloned into retroviral vectors for transduction of T cells to equip them with anti-EBV specificity. The TCR-modified T cells where then tested for their function towards LCLs to assess the chances for the use of EBV-redirected T cells in adoptive immunotherapy of EBV-associated disease. Like in previous reports, our EBV-specific TCRs at first did not confer effective activity against LCLs. Instead, we had to apply modifications to the TCR vectors to improve expression and function of the introduced TCRs. Codon optimization as well as replacement of the IRES site by a 2A peptide linker was required to significantly increase expression and function of transduced TCRs. Also, we found that the effectiveness of TCR transduced T cells is dependent on the target cell chosen. Our data show successful transfer of functionally active EBV-specific TCRs into T cells to render them effective against LCLs, representing the basis for the development of TCR-transgenic T cells for adoptive T cell transfer in EBV-associated disease.

Die adoptive T-Zell-Therapie (ATT) ist eine sich schnell entwickelnde Immuntherapie, die bei Patienten, die an verschiedenen Krebsarten leiden, eine positive klinische Reaktion anzeigt. Eine Variante der ATT ist eine T-Zellen-Rezeptor (TCR)-Gentherapie, bei der Patienten-T-Zellen mit krebsspezifischen TCRs ausgestattet werden. Die Herstellung der TCR-erzeugten T-Zellen ist schnell und robust und erfordert eine geringe Anfangsmenge an Patienten-T-Zellen. Der Mangel an verfügbaren krebsspezifischen TCRs, die auf verschiedene Moleküle des menschlichen Leukozytenantigens (HLA) der Klasse I beschränkt sind, schließt jedoch viele Patienten von der Krebsbehandlung aus. Die Generierung einer krebsspezifischen TCR-Bibliothek, die aus gut definierten TCRs besteht, könnte die Zahl der Patienten, die an klinischen Studien teilnehmen, erhöhen. Das Ziel dieser Doktorarbeit war es, Epstein-Barr-Virus (EBV)-spezifische TCRs zu identifizieren und zu isolieren, um eine EBV-spezifische TCR-Bibliothek als ein nützliches Werkzeug der TCR-Gentherapie bei der Behandlung von EBV-bedingten Krebserkrankungen zu generieren. Insgesamt wurden neun EBV-spezifische TCRs von EBV-positiven Spendern isoliert und charakterisiert, die verschiedene pHLA-Komplexe von EBV-Latentmembranproteinen (LMP1, LMP2A) und Kernprotein (EBNA3C) erkannten. Zusätzlich wurde ein neuartiges immunogenes LMP1-Epitop (QQNWWTLLV) entdeckt, das auf HLA-C*15:02 beschränkt ist. Definierte EBV-spezifische TCRs können als Grundlage für die EBV-spezifische TCR-Bibliothek verwendet werden, die eine wertvolle Quelle von TCRs für die schnelle Generierung von EBV-spezifischen T-Zellen zur Behandlung von Krebspatienten mit verschiedenen HLA-Typen darstellt. / Adoptive T cell therapy (ATT) is a fast developing immunotherapy indicating positive clinical response in patients suffering from different type of cancers. One type of the ATT is a T cell receptor (TCR) gene therapy, which involves endowing patient T cells with cancer-specific TCRs. Manufacturing of the TCR-engineered T cells is fast and robust, requiring small initial amount of patient T cells. However, lack of available cancer-specific TCRs restricted to various human leukocyte antigen (HLA) class I molecules eliminates many patients from cancer treatment. Generation of a cancer-specific TCR library consisting of well-defined TCRs could increase the number of patients enrolled in clinical trials. The aim of this PhD thesis was to identify and isolate Epstein-Barr virus (EBV)-specific TCRs in order to generate the EBV-specific TCR library as a useful tool of the TCR gene therapy for treatment of EBV-related malignancies. In total, nine EBV-specific TCRs of EBV-positive donors that recognized various pHLA complexes of EBV latent membrane proteins (LMP1, LMP2A) and nuclear protein (EBNA3C) were isolated and characterized. Additionally, a novel immunogenic LMP1 epitope (QQNWWTLLV) restricted to a HLA-C*15:02 was discovered. Defined EBV-specific TCRs can be used as a basis for the EBV-specific TCR library, which provides a valuable source of TCRs for rapid generation of EBV-specific T cells to treat cancer patients with different HLA types.

La protéine EB2 du virus d'Epstein-Barr (EBV) est une protéine du cycle réplicatif du virus indispensable à la production de particules virales. Elle permet l’accumulation dans le cytoplasme de certains ARNm viraux issus de gènes dépourvus d’intron. Pour mettre en évidence les mécanismes qui permettent à EB2 d’exporter ses ARNm cibles dans le cytoplasme, nous avons identifié différents partenaires cellulaires d’EB2 et nous avons étudié certaines de ces interactions d’un point de vue fonctionnel. Nous avons pu montrer qu’EB2 recrute directement le facteur général d'export des ARNm, TAP/NXF1, ce qui lui permet d’être exportée du noyau vers le cytoplasme. Puis nous avons montré qu’EB2 interagit avec SRp20, une protéine impliquée notamment dans la régulation de l'épissage et l'export des ARNm cellulaires. Cette interaction entre EB2 et SRp20 est indispensable pour l’accumulation dans le cytoplasme de certains ARNm cibles d’EB2, notamment parce que SRp20 semble permettre le recrutement d'EB2 sur ces ARNm. Enfin, nous avons montré qu’EB2 forme un dimère et nous avons caractérisé le domaine de la protéine responsable de cette interaction. La dimérisation d'EB2 semble essentielle pour que la protéine interagisse avec certains de ses partenaires comme SRp20 ou encore REF. / The Epstein-Barr virus (EBV) protein EB2 is an early protein essential for the production of infectous virions. EB2 allows the cytoplasmic accumulation of a subset of viral mRNAs derived from intronless genes. To highlight the mecanisms by which EB2 exports his targets mRNA, we identified cellular partners and studied the functional role of some of these interactions. We showed that EB2 recruits directly the cellular mRNA export factor TAP/NXF1 and this interaction allows EB2’s shuttling between the nucleus and the cytoplasm. The we showed that EB2 interacts with SRp20, a cellular protein implicated in splicing regulation and mRNA export. This interaction is essential for the efficient cytoplasmic accumulation of some EB2 target mRNAs, partly because SRp20 appears to be able to recruit EB2 on these mRNAs. Then we showed that EB2 dimerises and we characterized the domain necessary for this interaction. This dimerisation appears to be essential for EB2’s interaction with several partners, including SRp20 and REF.

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.

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

Tong Hung Man Joanna. / "June 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 137-149). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.