Cookies disclaimer

I agree Our site saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing our website without changing the browser settings you grant us permission to store that information on your device.

Current Filters

Currency:
GBP
Recipients:
University of Cambridge
Award Year:
2006

Results

Human cytomegalovirus evasion of natural killer cell functions 24 Apr 2006

Human cytomegalovirus (HCMV) provides a paradigm for how a complex viral pathogen persists and evades immune responses. HCMV evades cytotoxic T cells by downregulating class I MHC, but then has to evade natural killer (NK) cells. We have recently described a novel MHC-like gene unique to clinical isolates that inhibits NK cell lysis in a clonally dependant manor. The specific goals of the work proposed are to: (i)Define the mechanism of action of the novel viral NK evasion gene product (UL142) by identifying its ligand and how this mediates evasion of NK cell cytotoxicity.(ii)Construct deletion mutants of HCMV, for UL142 and other NK evasion genes, using Bacterial Artificial Chromosome (BAC) methodology , and use NK cell clones to determine whether CMV encodes further proteins, which mediate NK cell evasion. We will use these BAC-HCMV mutants to determine if the known evasion genes are redundant or directed at NK clone subsets, (this might explain why HCMV encodes multiple mechanisms to evade NK cells). (iii) Investigate subjects with HCMV infection to determine whether infection with HCMV shapes the expressed NK cell receptor repertoire. (iv)Determine if HCMV proteins can functionaly interact with NK receptors on HCMV specific CD8+ cells impairing effector function.

Amount: £250,076
Funder: The Wellcome Trust
Recipient: University of Cambridge

Molecular genetics of planar polarity in Drosophila 21 Feb 2006

Planar cell polarity (PCP) is exemplified by the direction of ciliary beat, the orientation of hairs or the alignment of stereocilia. The problem is pervasive and long range (how does information set up over an entire developing field convey axial information to single cells?) and local (how does a single cell read this polarising information and how does it liaise with its neighbours?). We have worked on PCP for 9 years using the Drosophila abdomen. We and others have shown that PCP depends on a novel mechanism. The pervasive system relies on interacting cadherin molecules (Dachsous, Fat) and the local system depends on the Frizzled receptor and another cadherin, Flamingo. We have published evidence that each cell is polarised by comparing the levels of activity of Frizzled in its neighbours, using the intercellular bridge made by Flamingo to do so. Now we want to test this model at the molecular level, using constructs made with all three cadherins and with Fz, assaying them both in flies and in cell culture. We will also investigate the long range system, asking how it receives information from the organising morphogen (Hedgehog) upstream and passes information to the local system downstream

Amount: £389,685
Funder: The Wellcome Trust
Recipient: University of Cambridge

Role of human herpesvirus 8 K5 gene product in the pathogenesis of pulmonary arterial hypertension. 03 Apr 2006

Identification of heterozygous germline mutations in the gene encoding the bone morphogenetic protein type II receptor (BMPR-II) in familial pulmonary arterial hypertension (PAH) is a major advance in understanding this condition. Our laboratory, and others, has demonstrated that a reduction in BMP receptor signalling is a feature common to many forms of PAH, even in the absence of identifiable mutations in the BMPR2 gene. Thus, factors that reduceBMP receptor expression or function may be critical to PAH pathogenesis. Recently human herpersvirus-8 (HHV-8) was identified in the pulmonary vasculature of 60% of cases of idiopathic PAH. Like other herpesviruses HHV-8 expresses immunoevasion genes. We (PJL) have shown that the HHV-8 encoded K3 and K5 genes ubiquitinate endogenous immunoreceptors, targeting them for endolysosomal degradation. Our preliminary data shows that K5 interferes with cell surface expression of BMP receptors. This is the first demonstration of aherpesvirus gene product subverting growth factor receptor expression. The original hypothesis underpinning these studies is that ubiquitination and

Amount: £183,726
Funder: The Wellcome Trust
Recipient: University of Cambridge

Early cell fate decisions and cell positioning in the mouse embryo. 01 Jun 2006

I propose three complementary approaches to study how early events can help to specify polarity of the mouse embryo. I first propose to study developmental cues in the egg whose animal-vegetal polarity dictates one axis of the future blastocyst, and the position of sperm entry determines the second axis. The sperm entry position sets the first cleavage plane and conveys a division advantage upon the cell inheriting it. I will investigate the cytoplasmic events underlying these two consequences of sperm entry and test their relative importance in establishing the embryonic abembryonic polarity of the blastocyst. I also propose to study why, although the animal pole of the egg can be removed without affecting development, its duplication is inhibitory. Secondly I will combine lineage tracing and transplantation studies to ask how polarity of the blastocyst, set up by the above processes, is transformed to give organised signalling centres in the postimplantation embryo. My focus will be to discover the origins of visceral endoderm with potential to signal to the epiblast of the egg cylinder. To determine when such signalling centres become active, I will first concentrate on transplantation experiments that test the ability of anterior visceral endoderm precursors to repress posterior gene activity. The extent of such experiments could be broadened by better knowledge of the patterns of gene expression from the blastocyst onwards. The third part of my proposal aims to identify genes that are expressed asymmetrically along axes of the blastocyst and/or at the earliest times within postimplantation signalling centres or their progenitors. My attention will centre upon finding genes that are differentially expressed in the animal and vegetal halves of the blastocyst or become uniquely expressed in progenitors of anterior visceral endoderm. These will be identified through the construction of subtractive cDNA libraries and by screening microarrays. I will select genes with expression patterns likely to be meaningful in the development of signalling centres and examine the consequences of both their ectopic expression and loss of expression using dsRNAi. In the longer term I propose to analyse how the patterns of expression of these or other genes are rebuilt following perturbation of development. Thus not only do I hope my work wil contribute to a molecular understanding of how asymmetries are established and transmitted to later stages of the embryo in normal development, but also will provide insight into the remarkable regulative properties of the mammalian embryo.

Amount: £2,417,906
Funder: The Wellcome Trust
Recipient: University of Cambridge

Therapeutic approaches for codon reiteration diseases 05 Jun 2006

I aim to develop therapeutic strategies for diseases associated with protein misfolding and intracellular aggregation, focussing on Huntington's disease (HD) and oculopharyngeal muscular dystrophy (OPMD). First, I will develop our findings that levels of mutant huntingtin fragments can be reduced by inducing autophagy. This strategy attenuates toxicity of the HD mutation in transgenic cell, fly and mouse models. Recent work in cell and fly models suggests that autophagy induction is beneficial for a much broader range of targets, including polyglutamine expansions underlying many spinocerebellar ataxias, and tau. Currently, the only autophagy-inducing drug that is known to reduce mutant huntingtin levels effectively in mammalian brains is rapamycin. While it is designed for long-term use, it has significant side-effects. My aims in the context of this component of the proposal are:1. Further the understanding of the machinery and regulation of mammalian autophagy to aid discovery of safer and more specific targets.2. Test autophagy upregulation as a therapeutic strategy for SCA3 and tauopathies in mouse models. Second, I will exploit our OPMD mouse model for testing 4 known safe drugs/compounds in vivo, on the basis of pilot data showing that they reduce aggregation and toxicity in OPMD cell models.

Amount: £1,645,643
Funder: The Wellcome Trust
Recipient: University of Cambridge

The role of immunosenescence in chronic hepatitis C infection. 07 Dec 2006

Introduction: Hepatitis C virus (HCV) affects 0.2 - 1% of the UK population causing cirrhosis, and hepatoma in a variable proportion. Factors that increase risk of progressive liver injury include male sex, immune suppression, alcohol abuse and critically, increased age. Many studies indicate an association between broad defects of T-cell responses (specific and non-specific) and persistent infection, which may be reversed by antiviraltherapy. Reduced immune function with ageing (immunosenescence) may be accelerated by chronic viral infection. Aim: To determine whether accelerated immunosenescence is present in patients with chronic HCV infectionand correlates with impaired immune responses to HCV or clinical outcome.Methods: Analysis of circulating/intrahepatic lymphocyte phenotype and function using healthy controls matched for age, sex and CMV (i) cross-sectional study of HCV exposed subjects of varied age and severity of liver disease with and without viraemia (ii) longitudinal study of HCV infected patients undergoing antiviral therapy or transplantation for cirrhosis or hepatoma. Finally to investigate circulating/intrahepatic lymphocyte phenotype in relation to HCV-specific T-cell function. Cell-surface phenotype for senescence associated markers, telomere length, cytokine production and proliferation will be analysed by flow-cytometry and correlated with markers of HCV outcome, including hepatic fibrosis, viral loadand response to antiviral therapy.

Amount: £134,019
Funder: The Wellcome Trust
Recipient: University of Cambridge

A prospective investigation of gene expression profiling in primary systemic vasculitis 07 Dec 2006

The primary systemic vasculitides are a group of complex, heterogeneous and poorly understood autoimmune disorders. A lack of clear guidelines on whom to treat with what, when and for how long results in a high associated morbidity and mortality. We aim to sample PSV patients at presentation with active disease and during several different treatment protocols as part of ongoing clinical trials and make detailed comparisons with gene expression seen in healthy controls and in another important, related autoimmune disease, SLE. Previous studies have analysed RNA derived from whole PBMC. We aim to analyse RNA collected from separated cell subsets using oligonucleotide microarrays and to correlate expression signatures with extensive clinical data. We then aim to validate such expression profiles as markers of diagnosis, prognosis, response to treatment and treatment-related toxicity by expanding our initial cohort and with the design of further clinical trials. Preliminary data included here confirms the validity of this approach and hints at interesting correlations to be pursued.

Amount: £242,463
Funder: The Wellcome Trust
Recipient: University of Cambridge

M.Phil in the History and Philosophy of Science. 30 Aug 2006

M.Phil in the History and Philosophy of Science and Medicine I plan to carry out my dissertation in the field of the History of Medicine, continuing my study of Chinese Medicine, and taking advantage of proposed closer links between the HPS Department and the Needham Research Institute in Cambridge. This specialises in East Asian science, technology and medicine. Research here would help me to build on my personal international interest. My current dissertation study has thrown up many interesting issues that I have not been able to research very thoroughly, this provides a focus for my M.Phil dissertation such as the shaping influence of newly involved large international health institutes (such as American National Institute of Health) on Chinese Medicine in Hong Kong. For the 3 essays required I would like to focus on the area of Science and Technology Studies, specifically the roles of gender and race in shaping modern science; another area I would focus on is the history of modern medicine, concentrating on feminist attitudes within the sphere of reproduction. I would like to concentrate on the role of Psychopharmacology in psychiatry in my third essay, part of the History and Philosophy of Mind area Research in these areas would fulfil and develop my interest in the history and philosophy of medicine, whilst providing opportunities for a broader outlook on science in general.

Amount: £21,452
Funder: The Wellcome Trust
Recipient: University of Cambridge

Secretion at the immunological synapse. 01 Dec 2006

The goal of this research is to identify and understand the mechanisms that regulate secretion from cytotoxic T lymphocytes (CTL). The secretory granules of CTL are unusual as they are also the lysosomes of these cells, and the mechanisms controlling their secretion differ from those of secretory granules in other cell types. The primary aim of this proposal is to use human genetic diseases in which CTL function is impaired to identify novel proteins required for secretion from CTL. We will complement this approach with use of lentiviral expression in CTL to identify additional proteins involved in secretion which might give rise to embryonic lethal mutations. We will combine molecular, biochemical, microscopical and immunological techniques to dissect the molecular interactions required for each step leading to secretion at the immunological synapse. Using these techniques we will determine the role of cytoskeletal proteins, exocyst and SNARE proteins in CTL secretion. We will also examine the later steps of CTL killing, characterising the microenvironment of the secretory cleft and the mechanisms that lead to membrane acquisition from target cells by CTL, asking whether this mechanism plays a role in regulating the CD8 response and in preventing hemophagocytosis

Amount: £2,757,509
Funder: The Wellcome Trust
Recipient: University of Cambridge

MARCH-VII, a regulator of transcriptional activity and immune cell activation? 22 May 2006

MARCH-VII, a regulator of transcriptional activity and immune cell activation? The aims of my project are: (i) To determine the role of MARCH7 in the ubiquitylation and transcriptional activity of NFAT. (ii) To determine the role of MARCH7 in T-cell activation and immune regulation in vivo.

Amount: £141,232
Funder: The Wellcome Trust
Recipient: University of Cambridge

CD40 and CD154: breaking and maintaining peripheral tolerance to pancreatic beta cells. 08 Feb 2006

CD40 and CD154: Breaking and maintaining peripheral tolerance to pancreatic beta cells 1. To determine the regulatory capacity of CD40-induced CD4+CD25+ T cells and the role of CD40 in their expansion. 2. To determine the point of divergence between the CD40 and TNFa signalling pathways and how this leads to distinct cellular outcomes. 3. To determine the role of TNFa in the prevention of CD40-induced expansion of CD4+CD25+ T cells.

Amount: £7,584
Funder: The Wellcome Trust
Recipient: University of Cambridge

Nuclear receptors and human disease. 11 Jul 2006

Many drugs are targeted at nuclear receptors and our aim is to investigate their role in human disease. Wellcome Trust support (1990-2006) has enabled us to identify and study the largest worldwide cohort (~200 families) with Resistance to Thyroid Hormone (RTH) and thyroid hormone receptor beta (TRbeta) mutations or insulin resistance with defects in peroxisome proliferator-activated receptor gamma (PPARgamma). Key future research goals are to: identify & functionally characterise novel genetic defects in human TR & PPARgamma signalling; characterise their phenotype to elucidate pathophysiological mechanisms; study defective receptor-containing human cells/tissues ex vivo. As well as TRbeta mutations, we will seek novel genetic defects mediating RTH and a human homologue of murine TRalpha resistance. We will investigate phenotypes of disordered energy expenditure & appetite, lipid and glucose homeostasis in RTH and use gene expression profiling to investigate pathogenic mechanisms and responses to treatment. We will identify novel PPARgamma gene defects in human metabolic phenotypes and elucidate molecular mechanisms by which germline or somatic (Pax8-PPARgamma) dominant negative forms of PPARgamma interfere with receptor function. We will investigate the metabolic phenotype and its treatment in vivo, and consequences of defective PPARgamma signalling in human primary cells ex vivo.

Amount: £955,795
Funder: The Wellcome Trust
Recipient: University of Cambridge

Molecular mechanisms in human insulin resistance. 23 Feb 2006

Our programme of research in human severe insulin resistance has been continuously supported by the Wellcome Trust since 1991. It has led to the discovery of several, novel molecular explanations for insulin resistance, linked those molecular defects to in vivo pathophysiology, translated research into clinical diagnostics and catalysed developments in research infrastructure and the independent careers of young investigators. Our specific aims over the next five years are i) To enhance the quality and size of our cohort of subjects with severe insulin resistance ii) To better understand the pathophysiology of disorders we have discovered, in particular the syndrome of AKT2 deficiency iii) To define novel molecular mechanisms of severe human insulin resistance. This will involve the functional genomic study of mutations we have recently found in five candidate genes, PRKAB1, GPLD1, PRKCQLIPE, FOXO3A and studying the properties of other novel variants that will emerge. In addition, we will look for sub-microscopic chromosomal abnormalities in subjects with insulin resistance and complex developmental features by comparative genomic hybridisation iv) To enhance our translational studies in human in vivo physiology and, ultimately, therapeutic trials v) To utilise our discoveries in severe insulin resistance to inform genetic studies in common metabolic disorders.

Amount: £1,380,038
Funder: The Wellcome Trust
Recipient: University of Cambridge

Molecular studies in rotavirus replication. 12 Jun 2006

Rotaviruses are a major cause of gastroenteritis in young children, leading to one hundred million rotavirus infections per annum worldwide, one quarter of all childhood diarrhoea hospitalisations, and over 600,000 deaths each year. There is an urgent need for an effective rotavirus vaccine. Recently, two live attenuated rotavirus vaccines have been found to be safe in large phase III clinical trials and have been licensed in various countries, in some cases for universal use in childhood vaccination programmes. Various aspects of the rotavirus replication cycle are still relatively poorly understood, and successful therapeutic approaches will require further investigation of rotavirus replication at a molecular level. Rotaviruses constitute a genus of the Reoviridae family. They possess a genome of 11 segments of double-stranded (ds) RNA, which encodes 6 structural (VP1-VP4, VP6, and VP7) and 6 non-structural proteins (NSP1-NSP6). The infectious article (=virion) is a non-enveloped icosahedron. The structural proteins are located in three layers, with the outer layer formed by VP4 and VP7, the intermediate layer by VP6, and the inner layer by VP1-VP3, and the particle structure is characterised by the wheel-like appearance as observed by electron microscopy. Rotaviruses have been classified according to the immunological reactivities and gene composition of VP6, the middle layer protein, defining at least 5 groups (A-E), with a further possible 2 groups (F-G). For group A rotaviruses, G and P types have been established for classification, according to the immunological reactivity and gene composition of VP7 and VP4, respectively.

Amount: £141,232
Funder: The Wellcome Trust
Recipient: University of Cambridge

Intracellular dynamics of the influenza A virus RNA polymerase and their role in influencing virus host range. 26 Apr 2006

WT Studentship for Ms Agnes Foglein : 4-year PhD studentship in Infection and Immunity. Influenza A virus has a segmented, negative stranded RNA genome. In order to replicate in an infected cell it has to transcribe this genomic vRNA into mRNA (for viral protein expression) and into cRNA; an exact copy that serves as a template for amplification of the genome for new viral particles. To achieve this, influenza virus encodes a viral RNA dependent RNA polymerase. This complex, consisting of 3 proteins - PA, PB1 and PB2 -transcribes all the three RNA species required by the virus: mRNA, cRNA and vRNA. However, to achieve this it needs to interact with the cellular transcription machinery to "steal" the cap of cellular mRNA and use it for viral mRNA. There is much evidence that the viral polymerase genes are a major determinant of host range and pathogenicity. Although all three viral polymerase subunits play an important role and the combination of these also has an influence, PB2 is especially important for host specificity. The amino acid at position 627 seems to be a "signature" for the virus, with avian strains preferentially displaying glutamic acid (Glu) and human strains lysine (Lys). Change from Glu627 to Lys induces severe pathogenicity and increased replication of avian virus in mice. As Shinya et al. show, the single amino acid substitution converts a nonlethal H5N1 virus isolated from man to a lethal virus in mice. However, the molecular mechanisms behind this host range determination are unclear. While cell tropism did not seem to be influenced by the variant of PB2 in a mouse model, the human variant showed accelerated viral spread in infected animals and higher virus titers were measure in cell culture models (Shinya et al. 2004). The aim of the project is to investigate what molecular mechanism lies behind the species specificity conferred by PB2.

Amount: £141,232
Funder: The Wellcome Trust
Recipient: University of Cambridge

Epigenetic Programming of the mouse germ line. 23 Jan 2006

Epigenetic Programming of the mouse germ line Major epigenetic reprogramming of the germ line occurs in the primodial germ cells (PGCs) in which parental imprints are erased. This is brought about by the dynamic removal and re-establishment of epigenetic marks in the nucleus, essentially involving histone modifications, DNA (de)methylation and chromatin remodelling. Both arginine and lysine residues can be methylated and one of the ways these histone modifications transmit their biological signals is through local binding factors (effector proteins) that recognise the distinct methylation marks. Currently, little is known about the identity of effectors that recognise methyl-arginine modifications. Very recently, tudor-domain containing proteins were shown to be able to bind to symmetric methylated arginines in polypeptides and were postulated to be general methyl-binding proteins. These are strong candidates that may be general effectors of methylarginine on histone tails. I will examine if this putative histone methyl-binding capability exists, and if so, how tudor proteins may potentially contribute to the germ line chromatin state during epigenetic reprogramming. Notably, my preliminary data have shown that several of these tudor-domain containing proteins appear to be restricted to the germ line, and absent in the soma. This strongly suggests that tudor family of proteins may have uncharacterised functions in germ line development in addition to a putative methyl-arginine binding ability. Although it remains to be established if tudor proteins are methylarginine effectors, their potential involvements in germ line development are interesting in their own rights. Finally, I am also aware of the possible wider roles of tudor proteins in pluripotency, and will address this possibility.

Amount: £23,661
Funder: The Wellcome Trust
Recipient: University of Cambridge

The role of inositol lipids and inositol phosphates in cellular function. 21 Feb 2006

We plan to improve our knowledge of the physiological functions of inositides by building on what we have learned during the current grant. (i) For inositol lipids we will investigate the localisation, regulation, molecular partners and physiological function of all three of the Type II PtdIns5P 4-kinases (PIPkins) using a combination of cell imaging, immunocytochemistry, biochemistry and knock-in tags in DT-40 cells. (ii) For inositol phosphates we will explore the function of Ins(1,4,5)P3 3-ki nase A and B in post-dendritic spines of hippocampal neurones and in astrocytes respectively, by a range of molecular techniques, principally by transfection with enzyme mutants lacking specific regulatory functions, by imaging their movement and proteolysis, and by calcium imaging either with dyes or with spine-targeted Ca2+ sensors. We will isolate specific physiological interacting proteins for GAP1IP4BP and GAP1m using knock-in tags in DT-40 cells. We will also explore the physiological cont ribution made by Ins(1,4,5)P3 3-kinase to InsP6 synthesis.

Amount: £1,005,848
Funder: The Wellcome Trust
Recipient: University of Cambridge

Multidisciplinary studies of the folding of structurally related proteins: how sequence variation affects protein folding, stability, mechanics and disease. 01 Jun 2006

The central theme of this proposal is to investigate the relationship between protein sequence, folding, function and disease at the molecular level. We use a powerful multidisciplinary approach combining biophysical, protein engineering, structural, computational and bioinformatics techniques. Four closely related areas of research are described:Core Studies: The Folding of Related Proteins. How far can we explain (or predict) differences within and between families? We will investigate the relative importance of sequence, secondary structure, topology and chain connectivity.Studies of Multidomain ProteinsOver 75% of human proteins have more than one domain. We will investigate how the folding of one domain is affected by its neighbours and how misfolding is avoided.Mutations and Disease.Most pathogenic mutations are thought to affect protein stability. We will investigate pathogenic mutationsin all-a proteins to see how far it is possible to predict these effects from model proteins. We will compare pathogenic mutations and SNPs on a quantitative basis.Molecular Basis of Protein ElasticityIf a protein is to remain active in the presence of an external force it has to remain folded. How this is achieved will be investigated by combining atomic force microscopy, protein engineering and simulation.

Amount: £1,319,905
Funder: The Wellcome Trust
Recipient: University of Cambridge