Project acronym 3D_Tryps
Project The role of three-dimensional genome architecture in antigenic variation
Researcher (PI) Tim Nicolai SIEGEL
Host Institution (HI) LUDWIG-MAXIMILIANS-UNIVERSITAET MUENCHEN
Call Details Starting Grant (StG), LS6, ERC-2016-STG
Summary Antigenic variation is a widely employed strategy to evade the host immune response. It has similar functional requirements even in evolutionarily divergent pathogens. These include the mutually exclusive expression of antigens and the periodic, nonrandom switching in the expression of different antigens during the course of an infection. Despite decades of research the mechanisms of antigenic variation are not fully understood in any organism.
The recent development of high-throughput sequencing-based assays to probe the 3D genome architecture (Hi-C) has revealed the importance of the spatial organization of DNA inside the nucleus. 3D genome architecture plays a critical role in the regulation of mutually exclusive gene expression and the frequency of translocation between different genomic loci in many eukaryotes. Thus, genome architecture may also be a key regulator of antigenic variation, yet the causal links between genome architecture and the expression of antigens have not been studied systematically. In addition, the development of CRISPR-Cas9-based approaches to perform nucleotide-specific genome editing has opened unprecedented opportunities to study the influence of DNA sequence elements on the spatial organization of DNA and how this impacts antigen expression.
I have adapted both Hi-C and CRISPR-Cas9 technology to the protozoan parasite Trypanosoma brucei, one of the most important model organisms to study antigenic variation. These techniques will enable me to bridge the field of antigenic variation research with that of genome architecture. I will perform the first systematic analysis of the role of genome architecture in the mutually exclusive and hierarchical expression of antigens in any pathogen.
The experiments outlined in this proposal will provide new insight, facilitating a new view of antigenic variation and may eventually help medical intervention in T. brucei and in other pathogens relying on antigenic variation for their survival.
Summary
Antigenic variation is a widely employed strategy to evade the host immune response. It has similar functional requirements even in evolutionarily divergent pathogens. These include the mutually exclusive expression of antigens and the periodic, nonrandom switching in the expression of different antigens during the course of an infection. Despite decades of research the mechanisms of antigenic variation are not fully understood in any organism.
The recent development of high-throughput sequencing-based assays to probe the 3D genome architecture (Hi-C) has revealed the importance of the spatial organization of DNA inside the nucleus. 3D genome architecture plays a critical role in the regulation of mutually exclusive gene expression and the frequency of translocation between different genomic loci in many eukaryotes. Thus, genome architecture may also be a key regulator of antigenic variation, yet the causal links between genome architecture and the expression of antigens have not been studied systematically. In addition, the development of CRISPR-Cas9-based approaches to perform nucleotide-specific genome editing has opened unprecedented opportunities to study the influence of DNA sequence elements on the spatial organization of DNA and how this impacts antigen expression.
I have adapted both Hi-C and CRISPR-Cas9 technology to the protozoan parasite Trypanosoma brucei, one of the most important model organisms to study antigenic variation. These techniques will enable me to bridge the field of antigenic variation research with that of genome architecture. I will perform the first systematic analysis of the role of genome architecture in the mutually exclusive and hierarchical expression of antigens in any pathogen.
The experiments outlined in this proposal will provide new insight, facilitating a new view of antigenic variation and may eventually help medical intervention in T. brucei and in other pathogens relying on antigenic variation for their survival.
Max ERC Funding
1 498 175 €
Duration
Start date: 2017-04-01, End date: 2022-03-31
Project acronym ADIMMUNE
Project Decoding interactions between adipose tissue immune cells, metabolic function, and the intestinal microbiome in obesity
Researcher (PI) Eran Elinav
Host Institution (HI) WEIZMANN INSTITUTE OF SCIENCE
Call Details Consolidator Grant (CoG), LS6, ERC-2018-COG
Summary Obesity and its metabolic co-morbidities have given rise to a rapidly expanding ‘metabolic syndrome’ pandemic affecting
hundreds of millions of individuals worldwide. The integrative genetic and environmental causes of the obesity pandemic
remain elusive. White adipose tissue (WAT)-resident immune cells have recently been highlighted as important factors
contributing to metabolic complications. However, a comprehensive understanding of the regulatory circuits governing their
function and the cell type-specific mechanisms by which they contribute to the development of metabolic syndrome is
lacking. Likewise, the gut microbiome has been suggested as a critical regulator of obesity, but the bacterial species and
metabolites that influence WAT inflammation are entirely unknown.
We propose to use our recently developed high-throughput genomic and gnotobiotic tools, integrated with CRISPR-mediated interrogation of gene function, microbial culturomics, and in-vivo metabolic analysis in newly generated mouse models, in order to achieve a new level of molecular understanding of how WAT immune cells integrate environmental cues into their crosstalk with organismal metabolism, and to explore the microbial contributions to the molecular etiology of WAT inflammation in the pathogenesis of diet-induced obesity. Specifically, we aim to (a) decipher the global regulatory landscape and interaction networks of WAT hematopoietic cells at the single-cell level, (b) identify new mediators of WAT immune cell contributions to metabolic homeostasis, and (c) decode how host-microbiome communication shapes the development of WAT inflammation and obesity.
Unraveling the principles of WAT immune cell regulation and their amenability to change by host-microbiota interactions
may lead to a conceptual leap forward in our understanding of metabolic physiology and disease. Concomitantly, it may
generate a platform for microbiome-based personalized therapy against obesity and its complications.
Summary
Obesity and its metabolic co-morbidities have given rise to a rapidly expanding ‘metabolic syndrome’ pandemic affecting
hundreds of millions of individuals worldwide. The integrative genetic and environmental causes of the obesity pandemic
remain elusive. White adipose tissue (WAT)-resident immune cells have recently been highlighted as important factors
contributing to metabolic complications. However, a comprehensive understanding of the regulatory circuits governing their
function and the cell type-specific mechanisms by which they contribute to the development of metabolic syndrome is
lacking. Likewise, the gut microbiome has been suggested as a critical regulator of obesity, but the bacterial species and
metabolites that influence WAT inflammation are entirely unknown.
We propose to use our recently developed high-throughput genomic and gnotobiotic tools, integrated with CRISPR-mediated interrogation of gene function, microbial culturomics, and in-vivo metabolic analysis in newly generated mouse models, in order to achieve a new level of molecular understanding of how WAT immune cells integrate environmental cues into their crosstalk with organismal metabolism, and to explore the microbial contributions to the molecular etiology of WAT inflammation in the pathogenesis of diet-induced obesity. Specifically, we aim to (a) decipher the global regulatory landscape and interaction networks of WAT hematopoietic cells at the single-cell level, (b) identify new mediators of WAT immune cell contributions to metabolic homeostasis, and (c) decode how host-microbiome communication shapes the development of WAT inflammation and obesity.
Unraveling the principles of WAT immune cell regulation and their amenability to change by host-microbiota interactions
may lead to a conceptual leap forward in our understanding of metabolic physiology and disease. Concomitantly, it may
generate a platform for microbiome-based personalized therapy against obesity and its complications.
Max ERC Funding
2 000 000 €
Duration
Start date: 2019-03-01, End date: 2024-02-29
Project acronym ADIPODIF
Project Adipocyte Differentiation and Metabolic Functions in Obesity and Type 2 Diabetes
Researcher (PI) Christian Wolfrum
Host Institution (HI) EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Call Details Starting Grant (StG), LS6, ERC-2007-StG
Summary Obesity associated disorders such as T2D, hypertension and CVD, commonly referred to as the “metabolic syndrome”, are prevalent diseases of industrialized societies. Deranged adipose tissue proliferation and differentiation contribute significantly to the development of these metabolic disorders. Comparatively little however is known, about how these processes influence the development of metabolic disorders. Using a multidisciplinary approach, I plan to elucidate molecular mechanisms underlying the altered adipocyte differentiation and maturation in different models of obesity associated metabolic disorders. Special emphasis will be given to the analysis of gene expression, postranslational modifications and lipid molecular species composition. To achieve this goal, I am establishing several novel methods to isolate pure primary preadipocytes including a new animal model that will allow me to monitor preadipocytes, in vivo and track their cellular fate in the context of a complete organism. These systems will allow, for the first time to study preadipocyte biology, in an in vivo setting. By monitoring preadipocyte differentiation in vivo, I will also be able to answer the key questions regarding the development of preadipocytes and examine signals that induce or inhibit their differentiation. Using transplantation techniques, I will elucidate the genetic and environmental contributions to the progression of obesity and its associated metabolic disorders. Furthermore, these studies will integrate a lipidomics approach to systematically analyze lipid molecular species composition in different models of metabolic disorders. My studies will provide new insights into the mechanisms and dynamics underlying adipocyte differentiation and maturation, and relate them to metabolic disorders. Detailed knowledge of these mechanisms will facilitate development of novel therapeutic approaches for the treatment of obesity and associated metabolic disorders.
Summary
Obesity associated disorders such as T2D, hypertension and CVD, commonly referred to as the “metabolic syndrome”, are prevalent diseases of industrialized societies. Deranged adipose tissue proliferation and differentiation contribute significantly to the development of these metabolic disorders. Comparatively little however is known, about how these processes influence the development of metabolic disorders. Using a multidisciplinary approach, I plan to elucidate molecular mechanisms underlying the altered adipocyte differentiation and maturation in different models of obesity associated metabolic disorders. Special emphasis will be given to the analysis of gene expression, postranslational modifications and lipid molecular species composition. To achieve this goal, I am establishing several novel methods to isolate pure primary preadipocytes including a new animal model that will allow me to monitor preadipocytes, in vivo and track their cellular fate in the context of a complete organism. These systems will allow, for the first time to study preadipocyte biology, in an in vivo setting. By monitoring preadipocyte differentiation in vivo, I will also be able to answer the key questions regarding the development of preadipocytes and examine signals that induce or inhibit their differentiation. Using transplantation techniques, I will elucidate the genetic and environmental contributions to the progression of obesity and its associated metabolic disorders. Furthermore, these studies will integrate a lipidomics approach to systematically analyze lipid molecular species composition in different models of metabolic disorders. My studies will provide new insights into the mechanisms and dynamics underlying adipocyte differentiation and maturation, and relate them to metabolic disorders. Detailed knowledge of these mechanisms will facilitate development of novel therapeutic approaches for the treatment of obesity and associated metabolic disorders.
Max ERC Funding
1 607 105 €
Duration
Start date: 2008-07-01, End date: 2013-06-30
Project acronym AHRIMMUNITY
Project The influence of Aryl hydrocarbon receptor ligands on protective and pathological immune responses
Researcher (PI) Brigitta Stockinger
Host Institution (HI) MEDICAL RESEARCH COUNCIL
Call Details Advanced Grant (AdG), LS6, ERC-2008-AdG
Summary The Aryl hydrocarbon receptor is an evolutionary conserved widely expressed transcription factor that mediates the toxicity of a substantial variety of exogenous toxins, but is also stimulated by endogenous physiological ligands. While it is known that this receptor mediates the toxicity of dioxin, this is unlikely to be its physiological function. We have recently identified selective expression of AhR in the Th17 subset of effector CD4 T cells. Ligation of AhR by a candidate endogenous ligand (FICZ) which is a UV metabolite of tryptophan causes expansion of Th17 cells and the induction of IL-22 production. As a consequence, AhR ligation will exacerbate autoimmune diseases such as experimental autoimmune encephalomyelitis. Little is known so far about the impact of AhR ligands on IL-17/IL-22 mediated immune defense functions. IL-22 is considered a pro-inflammatory Th17 cytokine, which is involved in the etiology of psoriasis, but it has also been shown to be a survival factor for epithelial cells. AhR is polymorphic and defined as high or low affinity receptor for dioxin leading to the classification of high and low responder mouse strains based on defined mutations. In humans similar polymorphisms exist and although on the whole human AhR is thought to be of low affinity in humans, there are identified mutations that confer high responder status. No correlations have been made with Th17 mediated immune responses in mice and humans. This study aims to investigate the role of AhR ligands and polymorphisms in autoimmunity as well as protective immune responses using both mouse models and human samples from normal controls as well as psoriasis patients.
Summary
The Aryl hydrocarbon receptor is an evolutionary conserved widely expressed transcription factor that mediates the toxicity of a substantial variety of exogenous toxins, but is also stimulated by endogenous physiological ligands. While it is known that this receptor mediates the toxicity of dioxin, this is unlikely to be its physiological function. We have recently identified selective expression of AhR in the Th17 subset of effector CD4 T cells. Ligation of AhR by a candidate endogenous ligand (FICZ) which is a UV metabolite of tryptophan causes expansion of Th17 cells and the induction of IL-22 production. As a consequence, AhR ligation will exacerbate autoimmune diseases such as experimental autoimmune encephalomyelitis. Little is known so far about the impact of AhR ligands on IL-17/IL-22 mediated immune defense functions. IL-22 is considered a pro-inflammatory Th17 cytokine, which is involved in the etiology of psoriasis, but it has also been shown to be a survival factor for epithelial cells. AhR is polymorphic and defined as high or low affinity receptor for dioxin leading to the classification of high and low responder mouse strains based on defined mutations. In humans similar polymorphisms exist and although on the whole human AhR is thought to be of low affinity in humans, there are identified mutations that confer high responder status. No correlations have been made with Th17 mediated immune responses in mice and humans. This study aims to investigate the role of AhR ligands and polymorphisms in autoimmunity as well as protective immune responses using both mouse models and human samples from normal controls as well as psoriasis patients.
Max ERC Funding
1 242 352 €
Duration
Start date: 2009-02-01, End date: 2014-01-31
Project acronym AIM2 INFLAMMASOME
Project Cytosolic recognition of foreign nucleic acids: Molecular and functional characterization of AIM2, a central player in DNA-triggered inflammasome activation
Researcher (PI) Veit Hornung
Host Institution (HI) UNIVERSITAETSKLINIKUM BONN
Call Details Starting Grant (StG), LS6, ERC-2009-StG
Summary Host cytokines, chemokines and type I IFNs are critical effectors of the innate immune response to viral and bacterial pathogens. Several classes of germ-line encoded pattern recognition receptors have been identified, which sense non-self nucleic acids and trigger these responses. Recently NLRP-3, a member of the NOD-like receptor (NLR) family, has been shown to sense endogenous danger signals, environmental insults and the DNA viruses adenovirus and HSV. Activation of NLRP-3 induces the formation of a large multiprotein complex in cells termed inflammasome , which controls the activity of pro-caspase-1 and the maturation of pro-IL-1² and pro-IL18 into their active forms. NLRP-3, however, does not regulate these responses to double stranded cytosolic DNA. We identified the cytosolic protein AIM2 as the missing receptor for cytosolic DNA. AIM2 contains a HIN200 domain, which binds to DNA and a pyrin domain, which associates with the adapter molecule ASC to activate both NF-ºB and caspase-1. Knock down of AIM2 down-regulates caspase-1-mediated IL-1² responses following DNA stimulation or vaccinia virus infection. Collectively, these observations demonstrate that AIM2 forms an inflammasome with the DNA ligand and ASC to activate caspase-1. Our underlying hypothesis for this proposal is that AIM2 plays a central role in host-defence to cytosolic microbial pathogens and also in DNA-triggered autoimmunity. The goals of this research proposal are to further characterize the DNA ligand for AIM2, to explore the molecular mechanisms of AIM2 activation, to define the contribution of AIM2 to host-defence against viral and bacterial pathogens and to assess its function in nucleic acid triggered autoimmune disease. The characterization of AIM2 and its role in innate immunity could open new avenues in the advancement of immunotherapy and treatment of autoimmune disease.
Summary
Host cytokines, chemokines and type I IFNs are critical effectors of the innate immune response to viral and bacterial pathogens. Several classes of germ-line encoded pattern recognition receptors have been identified, which sense non-self nucleic acids and trigger these responses. Recently NLRP-3, a member of the NOD-like receptor (NLR) family, has been shown to sense endogenous danger signals, environmental insults and the DNA viruses adenovirus and HSV. Activation of NLRP-3 induces the formation of a large multiprotein complex in cells termed inflammasome , which controls the activity of pro-caspase-1 and the maturation of pro-IL-1² and pro-IL18 into their active forms. NLRP-3, however, does not regulate these responses to double stranded cytosolic DNA. We identified the cytosolic protein AIM2 as the missing receptor for cytosolic DNA. AIM2 contains a HIN200 domain, which binds to DNA and a pyrin domain, which associates with the adapter molecule ASC to activate both NF-ºB and caspase-1. Knock down of AIM2 down-regulates caspase-1-mediated IL-1² responses following DNA stimulation or vaccinia virus infection. Collectively, these observations demonstrate that AIM2 forms an inflammasome with the DNA ligand and ASC to activate caspase-1. Our underlying hypothesis for this proposal is that AIM2 plays a central role in host-defence to cytosolic microbial pathogens and also in DNA-triggered autoimmunity. The goals of this research proposal are to further characterize the DNA ligand for AIM2, to explore the molecular mechanisms of AIM2 activation, to define the contribution of AIM2 to host-defence against viral and bacterial pathogens and to assess its function in nucleic acid triggered autoimmune disease. The characterization of AIM2 and its role in innate immunity could open new avenues in the advancement of immunotherapy and treatment of autoimmune disease.
Max ERC Funding
1 727 920 €
Duration
Start date: 2009-12-01, End date: 2014-11-30
Project acronym AimingT6SS
Project Mechanisms of dynamic localization of the bacterial Type 6 secretion system assembly
Researcher (PI) Marek BASLER
Host Institution (HI) UNIVERSITAT BASEL
Call Details Consolidator Grant (CoG), LS6, ERC-2019-COG
Summary The Type 6 secretion system (T6SS) allows Gram-negative bacteria to deliver toxins into both eukaryotic and bacterial target cells and thus cause disease or kill competitors. T6SS is composed of four main parts: a membrane complex, a baseplate and a long spring-like sheath wrapped around an inner tube. Sheath contraction generates a large amount of energy to push the tube with associated toxins through the baseplate and membrane complex out of the cell. However, the reach of the T6SS tube is limited and thus a direct contact with the target membrane and precise positioning of T6SS assembly is required for protein translocation. In this proposal, we will unravel principles of spatial and temporal coordination of T6SS assembly that we have recently observed in several bacterial species. We will study how cells sense attacks from neighboring bacteria to dynamically localize its T6SS. We will describe how bacteria initiate and position T6SS assembly in response to physical cell-cell interactions. We will identify the principles and the role of T6SS localization in intracellular pathogens. Using genetic and biochemical approaches, we will identify and characterize proteins interacting with the core components of T6SS and test their role in initiation and positioning of T6SS assembly. We will search for peptidoglycan remodeling enzymes required for T6SS assembly. We will use advanced microscopy techniques to describe dynamic localization of proteins upon T6SS activation to establish the order of their assembly. We will quantify how much T6SS aiming increases efficiency of protein delivery and T6SS function during bacterial competition and pathogenesis. Overall, we will unravel novel principles of spatial and temporal control of localization of protein complexes and show how this allows bacteria to quickly respond to external cues and interact with their environment.
Summary
The Type 6 secretion system (T6SS) allows Gram-negative bacteria to deliver toxins into both eukaryotic and bacterial target cells and thus cause disease or kill competitors. T6SS is composed of four main parts: a membrane complex, a baseplate and a long spring-like sheath wrapped around an inner tube. Sheath contraction generates a large amount of energy to push the tube with associated toxins through the baseplate and membrane complex out of the cell. However, the reach of the T6SS tube is limited and thus a direct contact with the target membrane and precise positioning of T6SS assembly is required for protein translocation. In this proposal, we will unravel principles of spatial and temporal coordination of T6SS assembly that we have recently observed in several bacterial species. We will study how cells sense attacks from neighboring bacteria to dynamically localize its T6SS. We will describe how bacteria initiate and position T6SS assembly in response to physical cell-cell interactions. We will identify the principles and the role of T6SS localization in intracellular pathogens. Using genetic and biochemical approaches, we will identify and characterize proteins interacting with the core components of T6SS and test their role in initiation and positioning of T6SS assembly. We will search for peptidoglycan remodeling enzymes required for T6SS assembly. We will use advanced microscopy techniques to describe dynamic localization of proteins upon T6SS activation to establish the order of their assembly. We will quantify how much T6SS aiming increases efficiency of protein delivery and T6SS function during bacterial competition and pathogenesis. Overall, we will unravel novel principles of spatial and temporal control of localization of protein complexes and show how this allows bacteria to quickly respond to external cues and interact with their environment.
Max ERC Funding
2 493 650 €
Duration
Start date: 2021-01-01, End date: 2025-12-31
Project acronym ALBUGON
Project Genomics and effectoromics to understand defence suppression and disease resistance in Arabidopsis-Albugo candida interactions
Researcher (PI) Jonathan Jones
Host Institution (HI) THE SAINSBURY LABORATORY
Call Details Advanced Grant (AdG), LS6, ERC-2008-AdG
Summary This project focuses on two questions about host/parasite interactions: how do biotrophic plant pathogens suppress host defence? and, what is the basis for pathogen specialization on specific host species? A broadly accepted model explains resistance and susceptibility to plant pathogens. First, pathogens make conserved molecules ( PAMPS ) such as flagellin, that plants detect via cell surface receptors, leading to PAMP-Triggered Immunity (PTI). Second, pathogens make effectors that suppress PTI. Third, plants carry 100s of Resistance (R) genes that detect an effector, and activate Effector-Triggered Immunity (ETI). One effector is sufficient to trigger resistance. Albugo candida (Ac) (white rust) strongly suppresses host defence; Ac-infected Arabidopsis are susceptible to pathogen races to which they are otherwise resistant. Ac is an oomycete, not a fungus. Arabidopsis is resistant to races of Ac that infect brassicas. The proposed project involves three programs. First ( genomics, transcriptomics and bioinformatics ), we will use next-generation sequencing (NGS) methods (Solexa and GS-Flex), and novel transcriptomics methods to define the genome sequence and effector set of three Ac strains, as well as carrying out >40- deep resequencing of 7 additional Ac strains. Second, ( effectoromics ), we will carry out functional assays using Effector Detector Vectors (Sohn Plant Cell 19:4077 [2007]), with the set of Ac effectors, screening for enhanced virulence, for suppression of defence, for effectors that are recognized by R genes in disease resistant Arabidopsis and for host effector targets. Third, ( resistance diversity ), we will characterize Arabidopsis germplasm for R genes to Ac, both for recognition of Arabidopsis strains of Ac, and for recognition in Arabidopsis of effectors from Ac strains that infect brassica. This proposal focuses on Ac, but will establish methods that could discover new R genes in non-hosts against many plant diseases.
Summary
This project focuses on two questions about host/parasite interactions: how do biotrophic plant pathogens suppress host defence? and, what is the basis for pathogen specialization on specific host species? A broadly accepted model explains resistance and susceptibility to plant pathogens. First, pathogens make conserved molecules ( PAMPS ) such as flagellin, that plants detect via cell surface receptors, leading to PAMP-Triggered Immunity (PTI). Second, pathogens make effectors that suppress PTI. Third, plants carry 100s of Resistance (R) genes that detect an effector, and activate Effector-Triggered Immunity (ETI). One effector is sufficient to trigger resistance. Albugo candida (Ac) (white rust) strongly suppresses host defence; Ac-infected Arabidopsis are susceptible to pathogen races to which they are otherwise resistant. Ac is an oomycete, not a fungus. Arabidopsis is resistant to races of Ac that infect brassicas. The proposed project involves three programs. First ( genomics, transcriptomics and bioinformatics ), we will use next-generation sequencing (NGS) methods (Solexa and GS-Flex), and novel transcriptomics methods to define the genome sequence and effector set of three Ac strains, as well as carrying out >40- deep resequencing of 7 additional Ac strains. Second, ( effectoromics ), we will carry out functional assays using Effector Detector Vectors (Sohn Plant Cell 19:4077 [2007]), with the set of Ac effectors, screening for enhanced virulence, for suppression of defence, for effectors that are recognized by R genes in disease resistant Arabidopsis and for host effector targets. Third, ( resistance diversity ), we will characterize Arabidopsis germplasm for R genes to Ac, both for recognition of Arabidopsis strains of Ac, and for recognition in Arabidopsis of effectors from Ac strains that infect brassica. This proposal focuses on Ac, but will establish methods that could discover new R genes in non-hosts against many plant diseases.
Max ERC Funding
2 498 923 €
Duration
Start date: 2009-01-01, End date: 2014-06-30
Project acronym ALLERGUT
Project Mucosal Tolerance and Allergic Predisposition: Does it all start in the gut?
Researcher (PI) Caspar OHNMACHT
Host Institution (HI) HELMHOLTZ ZENTRUM MUENCHEN DEUTSCHES FORSCHUNGSZENTRUM FUER GESUNDHEIT UND UMWELT GMBH
Call Details Starting Grant (StG), LS6, ERC-2016-STG
Summary Currently, more than 30% of all Europeans suffer from one or more allergic disorder but treatment is still mostly symptomatic due to a lack of understanding the underlying causality. Allergies are caused by type 2 immune responses triggered by recognition of harmless antigens. Both genetic and environmental factors have been proposed to favour allergic predisposition and both factors have a huge impact on the symbiotic microbiota and the intestinal immune system. Recently we and others showed that the transcription factor ROR(γt) seems to play a key role in mucosal tolerance in the gut and also regulates intestinal type 2 immune responses.
Based on these results I postulate two major events in the gut for the development of an allergy in the lifetime of an individual: First, a failure to establish mucosal tolerance or anergy constitutes a necessity for the outbreak of allergic symptoms and allergic disease. Second, a certain ‘core’ microbiome or pathway of the intestinal microbiota predispose certain individuals for the later development of allergic disorders. Therefore, I will address the following aims:
1) Influence of ROR(γt) on mucosal tolerance induction and allergic disorders
2) Elucidate the T cell receptor repertoire of intestinal Th2 and ROR(γt)+ Tregs and assess the role of alternative NFκB pathway for induction of mucosal tolerance
3) Identification of ‘core’ microbiome signatures or metabolic pathways that favour allergic predisposition
ALLERGUT will provide ground-breaking knowledge on molecular mechanisms of the failure of mucosal tolerance in the gut and will prove if the resident ROR(γt)+ T(reg) cells can function as a mechanistic starting point for molecular intervention strategies on the background of the hygiene hypothesis. The vision of ALLERGUT is to diagnose mucosal disbalance, prevent and treat allergic disorders even before outbreak and thereby promote Public Health initiative for better living.
Summary
Currently, more than 30% of all Europeans suffer from one or more allergic disorder but treatment is still mostly symptomatic due to a lack of understanding the underlying causality. Allergies are caused by type 2 immune responses triggered by recognition of harmless antigens. Both genetic and environmental factors have been proposed to favour allergic predisposition and both factors have a huge impact on the symbiotic microbiota and the intestinal immune system. Recently we and others showed that the transcription factor ROR(γt) seems to play a key role in mucosal tolerance in the gut and also regulates intestinal type 2 immune responses.
Based on these results I postulate two major events in the gut for the development of an allergy in the lifetime of an individual: First, a failure to establish mucosal tolerance or anergy constitutes a necessity for the outbreak of allergic symptoms and allergic disease. Second, a certain ‘core’ microbiome or pathway of the intestinal microbiota predispose certain individuals for the later development of allergic disorders. Therefore, I will address the following aims:
1) Influence of ROR(γt) on mucosal tolerance induction and allergic disorders
2) Elucidate the T cell receptor repertoire of intestinal Th2 and ROR(γt)+ Tregs and assess the role of alternative NFκB pathway for induction of mucosal tolerance
3) Identification of ‘core’ microbiome signatures or metabolic pathways that favour allergic predisposition
ALLERGUT will provide ground-breaking knowledge on molecular mechanisms of the failure of mucosal tolerance in the gut and will prove if the resident ROR(γt)+ T(reg) cells can function as a mechanistic starting point for molecular intervention strategies on the background of the hygiene hypothesis. The vision of ALLERGUT is to diagnose mucosal disbalance, prevent and treat allergic disorders even before outbreak and thereby promote Public Health initiative for better living.
Max ERC Funding
1 498 175 €
Duration
Start date: 2017-07-01, End date: 2022-06-30
Project acronym Anti-Virome
Project A combined evolutionary and proteomics approach to the discovery, induction and application of antiviral immunity factors
Researcher (PI) Frank Kirchhoff
Host Institution (HI) UNIVERSITAET ULM
Call Details Advanced Grant (AdG), LS6, ERC-2012-ADG_20120314
Summary "Humans are equipped with a variety of intrinsic immunity or host restriction factors. These evolved under positive selection pressure for diversification and represent a first line of defence against invading viruses. Unfortunately, however, many pathogens have evolved effective antagonists against our defences. For example, the capability of HIV-1 to counteract human restriction factors that interfere with reverse transcription, uncoating and virion release has been a prerequisite for the global spread of AIDS. We are just beginning to understand the diversity and induction of antiretroviral factors and how pandemic HIV-1 group M (major) strains evolved to counteract all of them. Here, I propose to use a genetics, proteomics and evolutionary approach to discover and define as-yet-unknown antiviral effectors and their inducers. To identify novel antiviral factors, we will examine the capability of all primate genes that are under strong positive selection pressure to inhibit HIV and its simian (SIV) precursors. This examination from the evolutionary perspective of the invading pathogen will also reveal which adaptations allowed HIV-1 to cause the AIDS pandemic. Furthermore, complex peptide-protein libraries representing essentially the entire human peptidome, will be utilized to identify novel specific inducers of antiviral restriction factors. My ultimate aim is to unravel the network of inducers and effectors of antiviral immunity - the ""Anti-Virome"" - and to use this knowledge to develop novel effective preventive and therapeutic approaches based on the induction of combinations of antiviral factors targeting different steps of the viral life cycle. The results of this innovative and interdisciplinary program will provide fundamental new insights into intrinsic immunity and may offer alternatives to conventional vaccine and therapeutic approaches because most restriction factors have broad antiviral activity and are thus effective against various pathogens."
Summary
"Humans are equipped with a variety of intrinsic immunity or host restriction factors. These evolved under positive selection pressure for diversification and represent a first line of defence against invading viruses. Unfortunately, however, many pathogens have evolved effective antagonists against our defences. For example, the capability of HIV-1 to counteract human restriction factors that interfere with reverse transcription, uncoating and virion release has been a prerequisite for the global spread of AIDS. We are just beginning to understand the diversity and induction of antiretroviral factors and how pandemic HIV-1 group M (major) strains evolved to counteract all of them. Here, I propose to use a genetics, proteomics and evolutionary approach to discover and define as-yet-unknown antiviral effectors and their inducers. To identify novel antiviral factors, we will examine the capability of all primate genes that are under strong positive selection pressure to inhibit HIV and its simian (SIV) precursors. This examination from the evolutionary perspective of the invading pathogen will also reveal which adaptations allowed HIV-1 to cause the AIDS pandemic. Furthermore, complex peptide-protein libraries representing essentially the entire human peptidome, will be utilized to identify novel specific inducers of antiviral restriction factors. My ultimate aim is to unravel the network of inducers and effectors of antiviral immunity - the ""Anti-Virome"" - and to use this knowledge to develop novel effective preventive and therapeutic approaches based on the induction of combinations of antiviral factors targeting different steps of the viral life cycle. The results of this innovative and interdisciplinary program will provide fundamental new insights into intrinsic immunity and may offer alternatives to conventional vaccine and therapeutic approaches because most restriction factors have broad antiviral activity and are thus effective against various pathogens."
Max ERC Funding
1 915 200 €
Duration
Start date: 2013-04-01, End date: 2018-03-31
Project acronym ANTIViR
Project Molecular mechanisms of interferon-induced antiviral restriction and signalling
Researcher (PI) Caroline GOUJON
Host Institution (HI) INSTITUT NATIONAL DE LA SANTE ET DE LA RECHERCHE MEDICALE
Call Details Starting Grant (StG), LS6, ERC-2017-STG
Summary Interferons (IFNs), which are signalling proteins produced by infected cells, are the first line of defence against viral infections. IFNs induce, in infected and neighbouring cells, the expression of hundreds of IFN-stimulated genes (ISGs). The ISGs in turn induce in cells a potent antiviral state, capable of preventing replication of most viruses, including Human Immunodeficiency Virus type 1 (HIV-1) and influenza A virus (FLUAV). Identifying the antiviral ISGs and understanding their mechanisms of action is therefore crucial to progress in the fight against viruses.
ISGs playing a role in the antiviral state have been identified, such as human MX1, a well-known antiviral factor able to restrict numerous viruses including FLUAV, and MX2, an HIV-1 inhibitor. Both proteins bind to viral components but their detailed mechanisms of action, as well as the consequences of restriction on the activation of the innate immune system, remain unclear. Moreover, our preliminary work shows that additional anti-HIV-1 and anti-FLUAV ISGs remain to identify.
In this context, this proposal seeks an ERC StG funding to explore 3 major aims: 1) unravelling the mechanisms of antiviral action of MX proteins, by taking advantage of their similar structure and engineered chimeric proteins, and by using functional genetic screens to identify their cofactors; 2) investigating the consequences of incoming virus recognition by MX proteins on innate immune signalling, by altering their expression in target cells and measuring the cell response in terms of gene induction and cytokine production; 3) identifying and characterizing new ISGs able to inhibit viral replication with a combination of powerful approaches, including a whole-genome CRISPR/Cas9 knock-out screen.
Overall, this proposal will provide a better understanding of the molecular mechanisms involved in the antiviral effect of IFN, and may guide future efforts to identify novel therapeutic targets against major pathogenic viruses.
Summary
Interferons (IFNs), which are signalling proteins produced by infected cells, are the first line of defence against viral infections. IFNs induce, in infected and neighbouring cells, the expression of hundreds of IFN-stimulated genes (ISGs). The ISGs in turn induce in cells a potent antiviral state, capable of preventing replication of most viruses, including Human Immunodeficiency Virus type 1 (HIV-1) and influenza A virus (FLUAV). Identifying the antiviral ISGs and understanding their mechanisms of action is therefore crucial to progress in the fight against viruses.
ISGs playing a role in the antiviral state have been identified, such as human MX1, a well-known antiviral factor able to restrict numerous viruses including FLUAV, and MX2, an HIV-1 inhibitor. Both proteins bind to viral components but their detailed mechanisms of action, as well as the consequences of restriction on the activation of the innate immune system, remain unclear. Moreover, our preliminary work shows that additional anti-HIV-1 and anti-FLUAV ISGs remain to identify.
In this context, this proposal seeks an ERC StG funding to explore 3 major aims: 1) unravelling the mechanisms of antiviral action of MX proteins, by taking advantage of their similar structure and engineered chimeric proteins, and by using functional genetic screens to identify their cofactors; 2) investigating the consequences of incoming virus recognition by MX proteins on innate immune signalling, by altering their expression in target cells and measuring the cell response in terms of gene induction and cytokine production; 3) identifying and characterizing new ISGs able to inhibit viral replication with a combination of powerful approaches, including a whole-genome CRISPR/Cas9 knock-out screen.
Overall, this proposal will provide a better understanding of the molecular mechanisms involved in the antiviral effect of IFN, and may guide future efforts to identify novel therapeutic targets against major pathogenic viruses.
Max ERC Funding
1 499 794 €
Duration
Start date: 2017-12-01, End date: 2022-11-30
