NIHRDataInsights/HRCSData huggingface dataset:
Title: Clinical and Immunological Evaluation of T cell- and Antibody-Inducing Viral Vector Vaccines against Blood-Stage Malar
Funder: Medical Research Council

Abstract: The development of a highly effective malaria vaccine remains an important but elusive goal. To date, blood-stage malaria candidate vaccines, based primarily on protein-in-adjuvant formulations, have almost all been selected for clinical trials based on their ability to induce growth inhibitory antibodies - assessed using an in vitro assay that lacks T cells or monocytes. Despite these extensive efforts, these technologies have sadly shown limited or no success in clinical settings. A key contributing factor to these difficulties is our limited understanding of protective immune responses in vivo in humans against blood-stage parasites. However, there is growing evidence for the role of T cells and antibody Fc-mediated effector functions in immunity to blood-stage malaria and yet, to date, no vaccine has sought to induce such responses. This research seeks to address the merits of using viral vectored vaccines encoding blood-stage malaria antigens in humans in Phase I/IIa clinical trials. These vaccines induce strong and protective T cell and Th1-type antibody responses against encoded antigens in animal models, and now provide the first opportunity to address fundamental questions in humans regarding the contribution of cellular and antibody Fc-mediated immune responses to protective efficacy against blood-stage malaria. This research will aim to assess the safety, immunogenicity and efficacy of viral vector blood-stage malaria vaccines; develop a new in vivo assay of antibody Fc effector function; and address fundamental questions about the immuno-modulatory effects of blood-stage parasite exposure on cellular immune responses in both malaria-na?ve and naturally-exposed individuals. Summary of key goals: 1. Characterise the immunogenicity of viral vector blood-stage malaria vaccines in human volunteers using multi-functional flow cytometry and ELIspot assays for T cell responses as well as ELISAs, GIA assays and memory B cell ELIspot assays for humoral responses. 2. Assess IgG Fc effector functions in vivo by adoptive transfer of IgG from immunised volunteers into mice transgenic for different human Fc?Rs infected with a mouse malaria parasite chimeric for P. falciparum MSP119. 3. Attempt to correlate immunological readouts with efficacy in Phase IIa challenge studies. 4. Assess second generation vaccine strategies in humans using combinations of viral vector and protein-in-adjuvant vaccines. 5. Assess the effects of blood-stage malaria parasite exposure in UK volunteers on cellular and humoral immune responses. 6. Undertake baseline studies in African adults and children to measure i) cellular immune responses to blood-stage antigens, and ii) assess antibody Fc effector functions against MSP119 using the transgenic mouse model.


Research activity codes: 3.4 VACCINES
Health categories: INFECTION
Title: DCS - An investigation to enhance immunity to influenza in elderly individuals through reversal of the immune senescence
Funder: Medical Research Council

Abstract: Influenza remains a global health concern and the recent emergence of H1N1 ?swine flu? has increased the potential for a new pandemic. Advances in viral genomics allow new viral strains to be sequenced rapidly and appropriate vaccine production may potentially be accomplished before seasonal epidemics. However, many individuals fail to achieve a protective immune response to vaccination and this problem is seen commonly in elderly individuals in whom influenza-associated morbidity and mortality is most marked. Cytomegalovirus (CMV) is a herpesvirus that infects the majority of the UK population and, like all viruses in this group, is never cleared from the host. The cellular immune response against CMV is critical in preventing viral reactivation but accumulates within the host such that it can represent over 10% of the total T cell pool. This impairs the host response to other infections and epidemiological studies have shown that CMV infection is associated with the development of immune senescence, ?frailty? and impaired immune response to influenza vaccination. In this proposal we present a Developmental Clinical Study in which we will utilise drugs used commonly in the treatment of herpes simplex virus infections to reduce the frequency of subclinical CMV reactivation in elderly individuals. Uniquely, the primary aim of this approach will be to suppress the CMV-specific T cell immune response and therefore improve in vivo immune function. In the first phase of the study we will determine the dose, treatment duration and efficacy of therapy with valacyclovir for suppression of the CMV-specific immune response. Once this information has been established the second phase will be a randomised phase II study of valacyclovir in elderly individuals in order to determine if treatment can lead to an improvement in the immune response to the annual influenza vaccination. This study is appropriate for the MRC DCS scheme as it represents a second line novel indication for a current medication and tackles a major clinical concern for UK health as well as contributing to the MRC strategic aim to promote healthy ageing. The proposal has developed from basic research into the immune response to herpesvirus infection and could have major implications for the management of immune dysfunction in the elderly.


Research activity codes: 5.1 PHARMACEUTICALS;6.1 PHARMACEUTICALS
Health categories: INFECTION
Title: Human Enterovirus 71 empty capsids produced by baculovirus expression as vaccines
Funder: Medical Research Council

Abstract: Viral vaccines produced from recombinant viral proteins offer clear advantages in terms of safety and speed of development when compared to attenuated or killed vaccines. However, development can be impeded by them being costly to produce, poor or incompletely immunogenic or both. Virus-like-particles (VLPs), structural mimics of the authentic virus, improve immunogenicity and are an attractive option that are being pursued for a number of viruses, but for some the expression constructs required and the yields obtained are technically challenging. Empty capsids, a form of VLP for picornaviruses, are a case in point and cannot be currently assembled at a scale that allows manufacture despite their attractiveness as vaccine candidates. We have developed a new technology that allows empty capsid assembly at high levels, overcoming previous yield restrictions. The genetic modifications used are generic and will allow the synthesis of any picornavirus empty capsids, such as HEV71 for which an effective vaccine has yet to be produced, at high levels in insect cells. The objectives of this application are to demonstrate efficient empty capsid assembly for HEV71 for a range of virus serotypes, to develop efficient extraction and purification regimens and to demonstrate their utility as both antigens and immunogens.


Research activity codes: 3.4 VACCINES
Health categories: INFECTION
Title: Development, evaluation and translation of next-generation sequencing tools to track MRSA transmission pathways
Funder: Medical Research Council

Abstract: Nosocomial pathogens represent one of the most significant challenges to the successful delivery of modern medical care. Revealing the routes of transmission and spread of nosocomial pathogens at local, regional, national and international levels is crucial to targeted control. This is severely constrained, however, by the inability to discern between strains of the same epidemiologically successful lineage. For example, two lineages of methicillin-resistant Staphylococcus aureus (MRSA) termed EMRSA-15 and -16 have become disseminated throughout the UK and cause most cases of MRSA infection, but current bacterial typing methods fail to distinguish between strains of the same lineage. This technology gap represents a major hindrance to the development of more effective infection control strategies since transmission of MRSA between patients and healthcare facilities cannot be differentiated from independent acquisition. We have developed a series of novel and synergistic tools to type, map and track nosocomial pathogens and to determine genetic events associated with shifts in patterns of transmission and infection. This involves the integrated use of whole genome sequence typing (which we have already shown to be capable of defining detailed phylogenetic structuring within a single MRSA lineage), a web-based interface that provides mapping and interactive tree building to place a given strain within its geographical and phylogenetic context, and a network model of patient movement between NHS facilities. The goal of this Consortium is to apply these tools to define transmission of ERMSA-15 and -16 at local and national levels in the UK, and to have demonstrated a clear role for this approach in disease control by the end of the grant. Our strategy is to build upon an existing grouping of internationally recognized scientists who have developed these tools, and to expedite their rapid introduction into UK healthcare systems Our objectives are to undertake a 3-stage programme of research (development, evaluation and implementation) in which we refine and further develop these tools, conduct prospective macro- and micro-epidemiological evaluation studies, and seek to integrate this technology into the healthcare infrastructure. The detailed reconstruction of MRSA transmission pathways would be predicted to have a dramatic effect on future strategies for control and prevention of nosocomial MRSA infection. Furthermore, our model is adaptable to other existing and emerging pathogens, and will strengthen the capacity and resilience of healthcare networks to control and prevent a spectrum of current and future infectious disease threats.


Research activity codes: 2.2 FACTORS RELATING TO PHYSICAL ENVIRONMENT;2.5 RESEARCH DESIGN AND METHODOLOGIES (AETIOLOGY)
Health categories: INFECTION
Title: Natural Killer cells as effectors of vaccine-induced immunity
Funder: Medical Research Council

Abstract: The aim of this programme is to explore the potential for Natural Killer (NK) cells to contribute to the effector phase of adaptive (acquired) immune responses to infection following vaccination. We have recently shown that NK cell cytokine and cytolytic activities are markedly enhanced after vaccination as a result of induction of antigen-specific, IL-2 secreting CD4+ T lymphocytes. Upon subsequent exposure to the pathogen, T cell-derived IL-2 synergises with signals from myeloid accessory cells (including IL-12, IL-18, IFN-alpha and contact-dependent costimulation) to induce extremely potent and rapid activation of NK cells. The aims of this programme are to determine the kinetics of induction and duration of NK responses post vaccination, the cellular and molecular requirements for NK cells to be activated post-vaccination and whether NK cells contribute to vaccine efficacy. The programme comprises three strands: 1. Observational studies in humans, in the UK and The Gambia undergoing immunisation with licensed vaccines, to characterise NK cell and CD4+ T cell IL-2 responses before, during and after vaccination, to determine whether NK / CD4+ T cell responses vary between individuals or with age at vaccination and to determine the longevity of the NK/CD4+ T cell responses and the effects of boosting. 2. A cohort study with nested case-control study, in The Gambia, to determine the prevalence, magnitude and longevity of NK and CD4+ T cell responses to hepatitis B virus (HBV) in individuals who were HBV vaccinated at birth, to correlate NK and T cell responses with humoral vaccine responses and with indicators of natural HBV infection, to determine whether NK/T cell responses correlate with protection against natural HBV infection, and to explore potential associations between NK/T cell responses, genetic, physiological and nutritional parameters. 3. Experimental studies in mouse models of infection to characterise NK cell responses to pathogens before and after infection and/or vaccination and to compare resistance to infection between intact mice and mice in which NK cells have been depleted after vaccination. NK and T cell responses will be assessed by flow cytometry, by functional in vitro assays (e.g. cytotoxicity) and (in mice) by experimental infection. We expect the work to provide new assays and new correlates of protection for rapid evaluation of vaccine efficacy, screening of new antigens and adjuvants, optimising dosing schedules and determining duration of protection. Where appropriate, this may lead to vaccines being specifically designed to induce NK responses.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS;3.4 VACCINES
Health categories: INFECTION
Title: Investigating protein-mediated staphylococcal biofilm formation
Funder: Medical Research Council

Abstract: Staphylococcus aureus and Staphylococcus epidermidis form biofilms on prosthetic devices. These infections cause significant morbidity and mortality and are difficult to treat with antibiotics; device-removal is frequently required. The biofilms are formed through both polysaccharide-mediated and, more recently discovered, protein-mediated interactions between bacterial cells. The cell-wall attached proteins SasG from S. aureus and Aap from S. epidermidis mediate biofilm formation and have many similarities. Both contain a string of G5 domains, require proteolytic processing for activity and dimerise in the presence of zinc. We provide preliminary data showing we have discovered a mechanism by which proteolysis switches-on zinc-mediated dimerisation of these proteins. We have developed a model of protein-mediated biofilm formation which is quite different to a recently published model. The overall aim of the research is to test the model to reveal the mechanism and molecular details of zinc-mediated dimerisation. The work will involve the expression and purification of domains from SasG and Aap and their structural and functional characterisation using a range of biophysical techniques and bacterial biofilm assays. Mass spectrometry will be used to identify the proteolytic cleavage site and the stoichiometry of zinc binding to protein dimers. X-ray crystallography will be used to determine the high resolution structure of the zinc-mediated G5-domain dimers which, our preliminary data suggests, are key for biofilm formation. The structures will be used to design/propose lead compounds for biofilm inhibition and these will be tested in a high-throughput fluorescence-based (FRET) assay that will be developed as part of the proposed work. Lower resolution techniques such as small angle X-ray scattering and analytical ultracentrifugation will be used to determine the shape of dimers of larger fragments of SasG and Aap. The shape of these dimers will reveal whether the proteins interact through single G5 domains at the N-terminal end of the cleaved proteins or through a multi-domain zipper, as proposed previously. Mass spectrometry and nuclear magnetic resonance spectroscopy will be used to test the proposal that the G5 domains from SasG and Aap (and other bacterial proteins) bind N-acetylglucosamine; a plausible mechanism by which protein-mediated and polysaccharide-mediated biofilm formation mechanisms could interact. The relevance of the structural and biophysical studies to biofilm formation will be tested in bacterial assays in the laboratories of our collaborators. Overall, the proposed research, if successful, will lead to a fundamental shift in the understanding of protein-mediated biofilm formation in these important nosocomial pathogens.


Research activity codes: 1.3 CHEMICAL AND PHYSICAL SCIENCES;2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: INFECTION
Title: PI3Kdelta regulation of influenza virus morbidity
Funder: Medical Research Council

Abstract: Seasonal influenza virus infections affect 5-15% of human population and can result in death due to severe pneumonia, multiple organ failure and acute respiratory distress-like syndrome. The vast majority (90%) of the deaths per year that occur due to seasonal influenza virus infection are in individuals 65 years old or older. However pandemic strains appear to cause significant morbidity in the young. Although, the exact mechanism of influenza virus pathogenicity is unknown, the induction of an overreacting immune response is the likely cause. Phosphoinositide 3-kinases (PI3K) are a family of enzymes involved in signal transduction and play a important role in immune cell function and development. PI3K may also be utilized by influenza virus to enhance viral replication. We have found that mice that have an inactivating mutation in the PI3K isoform p110delta(p110delta-/- mice) manifest significantly reduced morbidity after influenza type A virus infection compared to wild-type C57BL/6 mice. The numbers of lung infiltrating activated CD8+ T cells and NK cells, granulocytes, macrophages and CD11c+CD11b+ dendritic cells (DC) are significantly reduced in influenza virus infected p110delta-/- mice. Despite this, viral clearance is not delayed in p110delta-/- mice, which actually have 10-fold lower lung viral titers than controls. These studies suggest that p110delta may play a critical role in influenza virus induced lung inflammation and morbidity and may contribute to viral replication. In this proposal we will test the hypotheses that P110delta plays an important role in the pathogenesis of influenza type A virus infection and determine the mechanism by which p110delta deficiency protects mice from morbidity induced by influenza virus infection. We will make use of a novel conditional allele of P110delta that we have developed and validated. This will allow examination of the contribution of P110delta in the T cell lineage using CD4 Cre; in the B cell lineage using CD19Cre; and in lung epithelial cells using SPC-Cre. The specific aims are: Aim1. Determine whether P110delta deficiency in T cells affects virus-specific immunity. Aim2. Investigate whether inactivation of P110delta in B cells affects virus-specific immunity. Aim3. Investigate whether P110delta is required in viral production by epithelial cells.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: INFECTION
Title: Exploiting species-specific defects in virion assembly to identify cellular co-factors for HIV-1 replication
Funder: Medical Research Council

Abstract: The assembly of infectious HIV-1 particles requires the co-ordinated activities of viral gene products, particularly Gag and RNA, and cellular co-factors and pathways. Unlike human cells, rodent cells are notably deficient in supporting effective HIV-1 core assembly. By understanding the principles for such species-specific replication barriers, investigators have been able to learn a great deal about the interactions of HIV-1 with infected host cells. Indeed, previous work has established that the murine cell assembly deficiency is rescued by human co-factors provided in trans, by manipulating the membrane binding capabilities of the viral Gag protein, or by changing the nuclear export pathway used by viral RNA. Here, we outline an inter-disciplinary and collaborative project that aims to identify human co-factors important for HIV-1 assembly, and to define the mechanistic basis for their activities. First, we will conduct gain-of-function ?genetic? screens in murine cells to identify human cDNAs that can promote HIV-1 assembly; in parallel, and in collaboration with the Frankel and Sundquist groups, we will perform comparative proteomic screens for factors that interact with HIV-1 Gag, Rev or RNA in a manner that correlates with effective assembly. Second, subsequent cell biological, molecular genetic and biochemical assays in both murine- and human-based assay systems will address the molecular mechanism(s) that underlie the rescue of assembly, focusing on question such as interactions with viral and cellular RNAs and proteins, sub-cellular localisation, intra-cellular trafficking and viral infectivity. Importantly, our preliminary data validate the utility of the genetic strategy in that the human orthologues of the SR proteins, SRp40 and SRp55, as well as the nuclear export receptor, CRM1, can each stimulate assembly in murine cells; the mechanisms of action differ, however, in that SR proteins increase Gag expression whereas CRM1 has a dramatic effect on the efficiency of assembly itself. Finally, validated assembly co-factors will be co-expressed with established human co-factors (e.g., CD4, CYCT1) in attempts to create murine cells capable of supporting spreading HIV-1 replication. Though beyond the scope of this work, developing a living mouse model for HIV/AIDS infection has the potential to be highly instructive for work on pathogenesis, immune responses, transmission, vaccines, etc. In sum, we aim to identify novel interactions between HIV-1 and infected host cells that regulate virus assembly, with the goal of better understanding general principles of virus replication and human cell biology, as well as defining rational targets for future therapeutic exploitation.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: INFECTION