Relationships among Constructs of L2 Chinese Reading and Language Background.

Ph.D. Thesis. University of Hawaiʻi at Mānoa 2017

Colorado State University, College of Veterinary Medicine and Biomedical Sciences, 11th annual CVMBS research day scientific proceedings

Includes the Pfizer Research Award winner and abstracts only of the oral sessions and posters

The Function of Themis2 in B Cells

Thymocyte-expressed molecule involved in selection 2 (Themis2) is the second member of the Themis family. Recently, the first member of the Themis family, Themis, has been reported to be part of the TCR signalling cascade and its deletion severely affects thymocyte progression from the double positive to the single positive stage. All family members share similar domains and high sequence similarity and show tissue specific expression with Themis2 being expressed in B lymphocytes, macrophages and dendritic cells. THEMIS2 associates with BCR signalling molecules such as GRB2, VAV or LYN and is phosphorylated in response to BCR stimulation. For these reasons I hypothesised that Themis2 might have an important role in B cell development or activation. I show that Themis2 is expressed throughout the B cell lineage and exclude redundant expression of other Themis family members. After B cell activation Themis2 expression is downregulated. Analysis of a newly created Themis2-deficient mouse strain showed that B cell development proceeds normally in the absence of THEMIS2. Experiments on in vitro cultured Themis2-deficient primary B cells demonstrated that proliferation and survival, BCR internalisation and antigen presentation as well as expression of activation markers and cytokines were unaffected. RNA sequencing revealed only minor changes in transcription in follicular B cells, even after activation. Similarly, antibody levels to in vivo immunisation with T-dependent or T-independent antigens or challenge with influenza virus did not suggest that Themis2 is required for antibody responses either. Reactions to a model of acute allergic airway inflammation showed only marginally reduced cell numbers in the bronchoalveolar lavage fluid yet all other markers of inflammation were all normal. In conclusion, I found that Themis2 is not required for B cell development, activation or antibody responses. Further studies will be required to define the role of Themis2 in the immune system

The role of T-lymphocytes in the pathogenesis of dengue haemorrhagic fever

Dengue is one of the most important human diseases transmitted by an arthropod vector and the incidence of dengue virus infection has been increasing steadily throughout the world. Most infections are asymptomatic but a subset of patients experience a potentially fatal shock syndrome characterised by plasma leakage. Generally attributed to the phenomenon of antibody-dependent enhancement, recent observations indicate that T cells may influence the development of this disease and it is this arm of the immune response to dengue this thesis examines. It starts by describing the production of novel HLA "tetramers" required for the work and then examines the role played by CD8+ cytotoxic T lymphocytes (CTL). This work demonstrates that CTL showing high level cross reactivity between dengue serotypes tend to exhibit high avidity and can be expanded from blood samples taken during the acute phase of secondary dengue infection. These cells produce much higher levels of both type 1 and certain type 2 cytokines than more serotype specific populations. Highly cross-reactive cells cannot be detected in convalescence when populations demonstrating significant serotype specificity dominate. The next section of the thesis describes the generation and characterisation of dengue specific CD4+ T cell clones, many of which behave in a highly cross-reactive manner producing large amounts of type 1 cytokines and demonstrating perforin-mediated cytolytic activity associated with an increase in the expression of surface CD107. It debates whether a new epitope has been discovered and discusses the nature of CD4 degeneracy, and its contribution to early cross-reactive immune responses which may facilitate priming of other immune system components. In conclusion this thesis hypothesises that sequential infection with different dengue virus serotypes elicits highly activated, cross-reactive CTL from memory which produce high levels of pro-inflammatory cytokines. Dengue-specific cross-reactive CD4+ T cell populations are also generated from memory and are capable of producing even greater levels of pro-inflammatory cytokines, and perhaps priming other cell populations. These mediators lead to the development of fluid leak and shock. High-avidity CD8+ T cells are subsequently deleted, perhaps as a consequence of activation-induced cell death, and a more beneficial serotype-specific memory CTL pool generated. These observations have significant implications for our understanding of the role of virus-specific CTL in pathogenesis of dengue disease and consequently for the design of a safe, effective vaccine

A comparison of clinical outcome, quality of life, emotional well being and cognitive function in those with chronic granulomatous disease managed conservatively and curatively

PhD ThesisChronic Granulomatous Disease (CGD) is a primary immunodeficiency, characterised by serious infections and inflammation. It can be managed conservatively, with prophylactic antimicrobials, or curatively with haematopoietic stem cell transplant (HSCT). In the UK and Ireland there are cohorts of children managed both conservatively and curatively. Previous research has shown patients with CGD have low intelligence and increased emotional difficulties. Chronic diseases are known to result in poor quality of life. This study aimed to evaluate: clinical outcome; quality of life; emotional well being and cognitive function in children managed conservatively and curatively. Children were identified from specialists centres and advertising through special interest groups. Clinical data were collected from medical records. Children and parents completed questionnaires measuring quality of life, emotional and behavioural difficulties and self-esteem. Children underwent brief IQ tests. Results were compared to published norms for healthy children. Non-HSCT and post-HSCT groups were compared. 78 children were identified. 59 (80%) living children were recruited. Clinical information was available for 62 children (four deceased). 30 (48%) children had undergone HSCT. Children with CGD had 0.71 episodes of infection/admission/surgery per CGD life year (95%CI 0.69-0.75 events per year). Post-HSCT children had 0.15 events per transplant year (95%CI 0.09- 0.21 events per year). Post-HSCT survival was 90%. Parents and children reported quality of life significantly below normal for in the non-HSCT group. Post-HSCT scores were not significantly different from healthy norms. Parents of non-HSCT children reported increased emotional difficulties compared to healthy children. IQ was normal in both groups. Children with CGD have more serious infections, episodes of surgery and admissions compared to post-HSCT children. They also have poorer quality of life and are at risk of emotional difficulties. Post-HSCT children have normal quality of life. Cognitive function is normal in both non-HSCT and post-HSCT children.National Institute for Health Researc

Red Skies in the Morning—Professional Ethics at the Dawn of Cloud Computing

The article evaluates risks to clients’ confidential and privileged information when lawyers or law firms store such information in any cloud computing “space” against the requirements of the Model Rules of Professional Conduct and the New York Rules of Professional Conduct. It also evaluates pertinent liability provisions of some of the more commonly used cloud computing services (Amazon.com and Google) against the lawyer’s responsibilities. An interesting portion covers the latest thinking from NIST on cloud computing benefits and risks

The twofold role of Cloud Computing in Digital Forensics: target of investigations and helping hand to evidence analysis

This PhD thesis discusses the impact of Cloud Computing infrastructures on Digital Forensics in the twofold role of target of investigations and as a helping hand to investigators. The Cloud offers a cheap and almost limitless computing power and storage space for data which can be leveraged to commit either new or old crimes and host related traces. Conversely, the Cloud can help forensic examiners to find clues better and earlier than traditional analysis applications, thanks to its dramatically improved evidence processing capabilities. In both cases, a new arsenal of software tools needs to be made available. The development of this novel weaponry and its technical and legal implications from the point of view of repeatability of technical assessments is discussed throughout the following pages and constitutes the unprecedented contribution of this wor

In vitro expanded human CD4+CD25+ regulatory T cells suppress effector T cell proliferation.

Regulatory T cells (Tregs) have been shown to be critical in the balance between autoimmunity and tolerance and have been implicated in several human autoimmune diseases. However, the small number of Tregs in peripheral blood limits their therapeutic potential. Therefore, we developed a protocol that would allow for the expansion of Tregs while retaining their suppressive activity. We isolated CD4+CD25 hi cells from human peripheral blood and expanded them in vitro in the presence of anti-CD3 and anti-CD28 magnetic Xcyte Dynabeads and high concentrations of exogenous Interleukin (IL)-2. Tregs were effectively expanded up to 200-fold while maintaining surface expression of CD25 and other markers of Tregs: CD62L, HLA-DR, CCR6, and FOXP3. The expanded Tregs suppressed proliferation and cytokine secretion of responder PBMCs in co-cultures stimulated with anti-CD3 or alloantigen. Treg expansion is a critical first step before consideration of Tregs as a therapeutic intervention in patients with autoimmune or graft-versus-host disease

Washington University Senior Undergraduate Research Digest (WUURD), Spring 2018

From the Washington University Office of Undergraduate Research Digest (WUURD), Vol. 13, 05-01-2018. Published by the Office of Undergraduate Research. Joy Zalis Kiefer, Director of Undergraduate Research and Associate Dean in the College of Arts & Scien