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 BCELLMECHANICS
Project Regulation of antibody responses by B cell mechanical activity
Researcher (PI) Pavel Tolar
Host Institution (HI) IMPERIAL COLLEGE OF SCIENCE TECHNOLOGY AND MEDICINE
Call Details Consolidator Grant (CoG), LS6, ERC-2014-CoG
Summary The production of antibodies against pathogens is an effective mechanism of protection against a wide range of infections. However, some pathogens evade antibody responses by rapidly changing their composition. Designing vaccines that elicit antibody responses against invariant parts of the pathogen is a rational strategy to combat existing and emerging pathogens. Production of antibodies is initiated by binding of B cell receptors (BCRs) to foreign antigens presented on the surfaces of antigen presenting cells. This binding induces B cell signalling and internalisation of the antigens for presentation to helper T cells. Although it is known that T cell help controls B cell expansion and differentiation into antibody-secreting and memory B cells, how the strength of antigen binding to the BCR regulates antigen internalisation remains poorly understood. As a result, the response and the affinity maturation of individual B cell clones are difficult to predict, posing a problem for the design of next-generation vaccines. My aim is to develop an understanding of the cellular mechanisms that underlie critical B cell activation steps. My laboratory has recently described that B cells use mechanical forces to extract antigens from antigen presenting cells. We hypothesise that application of mechanical forces tests BCR binding strength and thereby regulates B cell clonal selection during antibody affinity maturation and responses to pathogen evasion. We propose to test this hypothesis by (1) determining the magnitude and timing of the forces generated by B cells, and (2) determining the role of the mechanical properties of BCR-antigen bonds in affinity maturation and (3) in the development of broadly neutralising antibodies. We expect that the results of these studies will contribute to our understanding of the mechanisms that regulate the antibody repertoire in response to infections and have practical implications for the development of vaccines.
Summary
The production of antibodies against pathogens is an effective mechanism of protection against a wide range of infections. However, some pathogens evade antibody responses by rapidly changing their composition. Designing vaccines that elicit antibody responses against invariant parts of the pathogen is a rational strategy to combat existing and emerging pathogens. Production of antibodies is initiated by binding of B cell receptors (BCRs) to foreign antigens presented on the surfaces of antigen presenting cells. This binding induces B cell signalling and internalisation of the antigens for presentation to helper T cells. Although it is known that T cell help controls B cell expansion and differentiation into antibody-secreting and memory B cells, how the strength of antigen binding to the BCR regulates antigen internalisation remains poorly understood. As a result, the response and the affinity maturation of individual B cell clones are difficult to predict, posing a problem for the design of next-generation vaccines. My aim is to develop an understanding of the cellular mechanisms that underlie critical B cell activation steps. My laboratory has recently described that B cells use mechanical forces to extract antigens from antigen presenting cells. We hypothesise that application of mechanical forces tests BCR binding strength and thereby regulates B cell clonal selection during antibody affinity maturation and responses to pathogen evasion. We propose to test this hypothesis by (1) determining the magnitude and timing of the forces generated by B cells, and (2) determining the role of the mechanical properties of BCR-antigen bonds in affinity maturation and (3) in the development of broadly neutralising antibodies. We expect that the results of these studies will contribute to our understanding of the mechanisms that regulate the antibody repertoire in response to infections and have practical implications for the development of vaccines.
Max ERC Funding
1 999 386 €
Duration
Start date: 2015-09-01, End date: 2020-08-31
Project acronym BoneMalar
Project Mechanisms of bone marrow sequestration during malaria infection
Researcher (PI) Matthias Marti
Host Institution (HI) UNIVERSITY OF GLASGOW
Call Details Consolidator Grant (CoG), LS6, ERC-2015-CoG
Summary Malaria remains a major problem of public health in developing countries. It is responsible for about 600000 deaths per year, predominantly children in sub-Saharan Africa. There is an urgent need for novel therapies as resistance against current treatments is widespread. The complex parasite biology requires a multifaceted approach targeting multiple life cycle stages and virulence pathways. The pathogenesis of the most deadly of human malaria parasites, Plasmodium falciparum, is related to the capability of infected red blood cells to sequester in deep tissues. Sequestration is critical for the completion of the red blood cell cycle because the release of parasites into the blood circulation allows recognition by surveillance macrophages and clearance in the spleen. A series of studies have since led to the understanding that sequestration of asexually replicating parasites is caused by the adherence of parasite infected red blood cells to the vascular endothelium of various tissues in the body.
We have recently demonstrated that gametocytes, the only stage capable of transmission to the mosquito vector, develop in the extravascular environment of the human bone marrow. Preliminary studies in the mouse model have confirmed this finding and also suggest existence of an asexual reservoir in the bone marrow. In this innovative multidiscipinary proposal we aim to investigate the host pathogen interactions at the interface between infected red blood cell and bone marrow vasculature. Specifically we will focus on the following questions: how do parasites home to bone marrow? What are the changes in the bone marrow endothelium upon infection? How do parasites adhere with and transmigrate across the vascular endothelium in the bone marrow? The proposed studies initiate detailed characterization of a new paradigm in malaria parasite interaction with the host vasculature and provide a compelling new avenue for intervention strategies.
Summary
Malaria remains a major problem of public health in developing countries. It is responsible for about 600000 deaths per year, predominantly children in sub-Saharan Africa. There is an urgent need for novel therapies as resistance against current treatments is widespread. The complex parasite biology requires a multifaceted approach targeting multiple life cycle stages and virulence pathways. The pathogenesis of the most deadly of human malaria parasites, Plasmodium falciparum, is related to the capability of infected red blood cells to sequester in deep tissues. Sequestration is critical for the completion of the red blood cell cycle because the release of parasites into the blood circulation allows recognition by surveillance macrophages and clearance in the spleen. A series of studies have since led to the understanding that sequestration of asexually replicating parasites is caused by the adherence of parasite infected red blood cells to the vascular endothelium of various tissues in the body.
We have recently demonstrated that gametocytes, the only stage capable of transmission to the mosquito vector, develop in the extravascular environment of the human bone marrow. Preliminary studies in the mouse model have confirmed this finding and also suggest existence of an asexual reservoir in the bone marrow. In this innovative multidiscipinary proposal we aim to investigate the host pathogen interactions at the interface between infected red blood cell and bone marrow vasculature. Specifically we will focus on the following questions: how do parasites home to bone marrow? What are the changes in the bone marrow endothelium upon infection? How do parasites adhere with and transmigrate across the vascular endothelium in the bone marrow? The proposed studies initiate detailed characterization of a new paradigm in malaria parasite interaction with the host vasculature and provide a compelling new avenue for intervention strategies.
Max ERC Funding
2 298 557 €
Duration
Start date: 2016-06-01, End date: 2021-05-31
Project acronym CholeraIndex
Project Pathoecology of Vibrio cholerae to better understand cholera index cases in endemic areas
Researcher (PI) Melanie BLOKESCH
Host Institution (HI) ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Call Details Consolidator Grant (CoG), LS6, ERC-2016-COG
Summary Cholera is one of the oldest infectious diseases known and remains a major burden in many developing countries. The World Health Organization estimates that up to 4 million cases of cholera occur annually. The transmission of cholera by contaminated water, particularly under epidemic conditions, was first reported in the 19th century. However, early volunteer studies suggested that an incredibly high infectious dose (ID) is required to produce disease symptoms, in contrast to most other intestinal pathogens. Therefore, the mechanism of infection of index cases at the onset of an outbreak is unclear. This proposal aims to fill this knowledge gap by studying how the environmental lifestyle of the causative agent of the disease, the bacterium Vibrio cholerae, may prime the pathogen for intestinal colonization. We hypothesize that one of the natural niches of the bacterium (chitinous surfaces) fosters biofilm formation and provides a competitive advantage over co-colonizing bacteria. As an adaptive trait, passage of chitin-attached sessile V. cholerae through the acidic environment of the human stomach might be vastly facilitated compared to planktonic bacteria. Moreover, interbacterial warfare exerted by V. cholerae on these biotic surfaces may help the pathogen overcome the colonization barrier imposed by the human microbiota upon ingestion. The mechanism by which V. cholerae leaves the sessile lifestyle and the regulatory circuits involved in this process will also be investigated in this project. In summary, our goal is to elucidate the environmental community structures of V. cholerae that may enhance transmissibility from the ecosystem to humans in endemic areas resulting in the infection of index cases.
Summary
Cholera is one of the oldest infectious diseases known and remains a major burden in many developing countries. The World Health Organization estimates that up to 4 million cases of cholera occur annually. The transmission of cholera by contaminated water, particularly under epidemic conditions, was first reported in the 19th century. However, early volunteer studies suggested that an incredibly high infectious dose (ID) is required to produce disease symptoms, in contrast to most other intestinal pathogens. Therefore, the mechanism of infection of index cases at the onset of an outbreak is unclear. This proposal aims to fill this knowledge gap by studying how the environmental lifestyle of the causative agent of the disease, the bacterium Vibrio cholerae, may prime the pathogen for intestinal colonization. We hypothesize that one of the natural niches of the bacterium (chitinous surfaces) fosters biofilm formation and provides a competitive advantage over co-colonizing bacteria. As an adaptive trait, passage of chitin-attached sessile V. cholerae through the acidic environment of the human stomach might be vastly facilitated compared to planktonic bacteria. Moreover, interbacterial warfare exerted by V. cholerae on these biotic surfaces may help the pathogen overcome the colonization barrier imposed by the human microbiota upon ingestion. The mechanism by which V. cholerae leaves the sessile lifestyle and the regulatory circuits involved in this process will also be investigated in this project. In summary, our goal is to elucidate the environmental community structures of V. cholerae that may enhance transmissibility from the ecosystem to humans in endemic areas resulting in the infection of index cases.
Max ERC Funding
1 999 988 €
Duration
Start date: 2018-02-01, End date: 2023-01-31
Project acronym ChronosAntibiotics
Project Exploring the bacterial cell cycle to re-sensitize antibiotic-resistant bacteria
Researcher (PI) MARIANA LUISA TOMAS GOMES DE PINHO
Host Institution (HI) UNIVERSIDADE NOVA DE LISBOA
Call Details Consolidator Grant (CoG), LS6, ERC-2017-COG
Summary Over the next 35 years, antibiotic resistant bacteria are expected to kill more than 300 million people. The need to find alternative strategies for antimicrobial therapies remains a global challenge with several bottlenecks in the antibiotic discovery process. Using Staphylococcus aureus, the most common multidrug-resistant bacterium in the European Union and an excellent model organism for cell division in cocci, we propose:
(i) to find new pathways to re-sensitize resistant bacteria. Bacteria undergo major morphology changes during the cell cycle. We hypothesize that these changes generate windows of opportunity during which bacteria are more susceptible or more tolerant to the action of antibiotics. We will identify key regulators of the cell cycle in order to manipulate the duration of windows of opportunity for the action of existing antibiotics.
(ii) to develop new fluorescence-based reporters for whole-cell screenings of antimicrobial compounds with new modes of action, including compounds that arrest or delay the cell cycle; compounds that target non-essential pathways that are required for expression of resistance against existing antibiotics and therefore can be used as synergistic drugs for combination therapies; compounds that inhibit the production of virulence factors and compounds that revert persister states that are phenotypically resistant to antibiotics.
(iii) to unravel new modes of action of antibiotics by using the constructed reporter strains as powerful tools to learn how antibiotics act at the single cell level.
Over the past years, my group has become expert on the biology of S. aureus, has constructed powerful biological tools to study cell division and synthesis of the cell surface and has studied mechanisms of action of various antimicrobial compounds. We are therefore in a privileged position to quickly unravel the function of new players in the bacterial cell cycle and simultaneously contribute to accelerate antibiotic discovery.
Summary
Over the next 35 years, antibiotic resistant bacteria are expected to kill more than 300 million people. The need to find alternative strategies for antimicrobial therapies remains a global challenge with several bottlenecks in the antibiotic discovery process. Using Staphylococcus aureus, the most common multidrug-resistant bacterium in the European Union and an excellent model organism for cell division in cocci, we propose:
(i) to find new pathways to re-sensitize resistant bacteria. Bacteria undergo major morphology changes during the cell cycle. We hypothesize that these changes generate windows of opportunity during which bacteria are more susceptible or more tolerant to the action of antibiotics. We will identify key regulators of the cell cycle in order to manipulate the duration of windows of opportunity for the action of existing antibiotics.
(ii) to develop new fluorescence-based reporters for whole-cell screenings of antimicrobial compounds with new modes of action, including compounds that arrest or delay the cell cycle; compounds that target non-essential pathways that are required for expression of resistance against existing antibiotics and therefore can be used as synergistic drugs for combination therapies; compounds that inhibit the production of virulence factors and compounds that revert persister states that are phenotypically resistant to antibiotics.
(iii) to unravel new modes of action of antibiotics by using the constructed reporter strains as powerful tools to learn how antibiotics act at the single cell level.
Over the past years, my group has become expert on the biology of S. aureus, has constructed powerful biological tools to study cell division and synthesis of the cell surface and has studied mechanisms of action of various antimicrobial compounds. We are therefore in a privileged position to quickly unravel the function of new players in the bacterial cell cycle and simultaneously contribute to accelerate antibiotic discovery.
Max ERC Funding
2 533 500 €
Duration
Start date: 2018-03-01, End date: 2023-02-28
Project acronym COMBAT
Project Clearance Of Microbial Biofilms by Advancing diagnostics and Therapy
Researcher (PI) Susanne Christiane Haeussler
Host Institution (HI) HELMHOLTZ-ZENTRUM FUR INFEKTIONSFORSCHUNG GMBH
Call Details Consolidator Grant (CoG), LS6, ERC-2016-COG
Summary Every year chronic infections in patients due to biofilm formation of pathogenic bacteria are a multi-billion Euro burden to national healthcare systems. Despite improvements in technology and medical services, morbidity and mortality due to chronic infections have remained unchanged over the past decades. The emergence of a chronic infection disease burden calls for the development of modern diagnostics for biofilm resistance profiling and new therapeutic strategies to eradicate biofilm-associated infections. However, many unsuccessful attempts to address this need teach us that alternative perspectives are needed to meet the challenges.
The project is committed to develop innovative diagnostics and to strive for therapeutic solutions in patients suffering from biofilm-associated infections. The objective is to apply data-driven science to unlock the potential of microbial genomics. This new approach uses tools of advanced microbiological genomics and machine learning in genome-wide association studies on an existing unprecedentedly large dataset. This dataset has been generated in my group within the last five years and comprises sequence variation and gene expression information of a plethora of clinical Pseudomonas aeruginosa isolates. The wealth of patterns and characteristics of biofilm resistance are invisible at a smaller scale and will be interpreted within context and domain-specific knowledge.
The unique combination of basic molecular biology research, technology-driven approaches and data-driven science allows pioneer research dedicated to advance strategies to combat biofilm-associated infections. My approach does not only provide a prediction of biofilm resistance based on the bacteria´s genotype but also holds promise to transform treatment paradigms for the management of chronic infections and by interference with bacterial stress responses will promote the effectiveness of antimicrobials in clinical use to eradicate biofilm infections.
Summary
Every year chronic infections in patients due to biofilm formation of pathogenic bacteria are a multi-billion Euro burden to national healthcare systems. Despite improvements in technology and medical services, morbidity and mortality due to chronic infections have remained unchanged over the past decades. The emergence of a chronic infection disease burden calls for the development of modern diagnostics for biofilm resistance profiling and new therapeutic strategies to eradicate biofilm-associated infections. However, many unsuccessful attempts to address this need teach us that alternative perspectives are needed to meet the challenges.
The project is committed to develop innovative diagnostics and to strive for therapeutic solutions in patients suffering from biofilm-associated infections. The objective is to apply data-driven science to unlock the potential of microbial genomics. This new approach uses tools of advanced microbiological genomics and machine learning in genome-wide association studies on an existing unprecedentedly large dataset. This dataset has been generated in my group within the last five years and comprises sequence variation and gene expression information of a plethora of clinical Pseudomonas aeruginosa isolates. The wealth of patterns and characteristics of biofilm resistance are invisible at a smaller scale and will be interpreted within context and domain-specific knowledge.
The unique combination of basic molecular biology research, technology-driven approaches and data-driven science allows pioneer research dedicated to advance strategies to combat biofilm-associated infections. My approach does not only provide a prediction of biofilm resistance based on the bacteria´s genotype but also holds promise to transform treatment paradigms for the management of chronic infections and by interference with bacterial stress responses will promote the effectiveness of antimicrobials in clinical use to eradicate biofilm infections.
Max ERC Funding
1 998 750 €
Duration
Start date: 2017-05-01, End date: 2022-04-30
Project acronym CoPathoPhage
Project Pathogen-phage cooperation during mammalian infection
Researcher (PI) Anat Herskovits
Host Institution (HI) TEL AVIV UNIVERSITY
Call Details Consolidator Grant (CoG), LS6, ERC-2018-COG
Summary Most bacterial pathogens are lysogens, namely carry DNA of active phages within their genome, referred to as prophages. While these prophages have the potential to turn under stress into infective viruses which kill their host bacterium in a matter of minutes, it is unclear how pathogens manage to survive this internal threat under the stresses imposed by their invasion into mammalian cells. In the proposed project, we will study the hypothesis that a complex bacteria-phage cooperative adaptation supports virulence during mammalian infection while preventing inadvertent killing by phages. Several years ago, we uncovered a novel pathogen-phage interaction, in which an infective prophage promotes the virulence of its host, the bacterial pathogen Listeria monocytogenes (Lm), via adaptive behaviour. More recently, we discovered that the prophage, though fully infective, is non-autonomous- completely dependent on regulatory factors derived from inactive prophage remnants that reside in the Lm chromosome. These findings lead us to propose that the intimate cross-regulatory interactions between all phage elements within the genome (infective and remnant), are crucial in promoting bacteria-phage patho-adaptive behaviours in the mammalian niche and thereby bacterial virulence. In the proposed project, we will investigate specific cross-regulatory and cooperative mechanisms of all the phage elements, study the domestication of phage remnant-derived regulatory factors, and examine the hypothesis that they collectively form an auxiliary phage-control system that tempers infective phages. Finally, we will examine the premise that the mammalian niche drives the evolution of temperate phages into patho-adaptive phages, and that phages that lack this adaptation may kill host pathogens during infection. This work is expected to provide novel insights into bacteria-phage coexistence in mammalian environments and to facilitate the development of innovative phage therapy strategies.
Summary
Most bacterial pathogens are lysogens, namely carry DNA of active phages within their genome, referred to as prophages. While these prophages have the potential to turn under stress into infective viruses which kill their host bacterium in a matter of minutes, it is unclear how pathogens manage to survive this internal threat under the stresses imposed by their invasion into mammalian cells. In the proposed project, we will study the hypothesis that a complex bacteria-phage cooperative adaptation supports virulence during mammalian infection while preventing inadvertent killing by phages. Several years ago, we uncovered a novel pathogen-phage interaction, in which an infective prophage promotes the virulence of its host, the bacterial pathogen Listeria monocytogenes (Lm), via adaptive behaviour. More recently, we discovered that the prophage, though fully infective, is non-autonomous- completely dependent on regulatory factors derived from inactive prophage remnants that reside in the Lm chromosome. These findings lead us to propose that the intimate cross-regulatory interactions between all phage elements within the genome (infective and remnant), are crucial in promoting bacteria-phage patho-adaptive behaviours in the mammalian niche and thereby bacterial virulence. In the proposed project, we will investigate specific cross-regulatory and cooperative mechanisms of all the phage elements, study the domestication of phage remnant-derived regulatory factors, and examine the hypothesis that they collectively form an auxiliary phage-control system that tempers infective phages. Finally, we will examine the premise that the mammalian niche drives the evolution of temperate phages into patho-adaptive phages, and that phages that lack this adaptation may kill host pathogens during infection. This work is expected to provide novel insights into bacteria-phage coexistence in mammalian environments and to facilitate the development of innovative phage therapy strategies.
Max ERC Funding
2 200 000 €
Duration
Start date: 2019-10-01, End date: 2024-09-30
Project acronym Danger ATP
Project Regulation of inflammatory response by extracellular ATP and P2X7 receptor signalling: through and beyond the inflammasome
Researcher (PI) Pablo Pelegrin Vivancos
Host Institution (HI) FUNDACION PARA LA FORMACION E INVESTIGACION SANITARIAS DE LA REGION DE MURCIA
Call Details Consolidator Grant (CoG), LS6, ERC-2013-CoG
Summary Inflammatory diseases affect over 80 million people worldwide and accompany many diseases of industrialized countries, being the majority of them infection-free conditions. There are few efficient anti-inflammatory drugs to treat chronic inflammation and thus, there is an urgent need to validate novel targets. We now know that innate immunity is the main coordinator and driver of inflammation. Recently, we and others have shown that the activation of purinergic P2X7 receptors (P2X7R) in immune cells is a novel and increasingly validated pathway to initiate inflammation through the activation of the NLRP3 inflammasome and the release of IL-1β and IL-18 cytokines. However, how NLRP3 sense P2X7R activation is not fully understood. Furthermore, extracellular ATP, the physiological P2X7R agonist, is a crucial danger signal released by injured cells, and one of the most important mediators of infection-free inflammation. We have also identified novel signalling roles for P2X7R independent on the NLRP3 inflammasome, including the release of proteases or inflammatory lipids. Therefore, P2X7R has generated increasing interest as a therapeutic target in inflammatory diseases, being drug like P2X7R antagonist in clinical trials to treat inflammatory diseases. However, it is often questioned the functionality of P2X7R in vivo, where it is thought that extracellular ATP levels are below the threshold to activate P2X7R. The overall significance of this proposal relays to elucidate how extracellular ATP controls host-defence in vivo, ultimately depicting P2X7R signalling through and beyond inflammasome activation. We foresee that our results will generate a leading innovative knowledge about in vivo extracellular ATP signalling during the host response to infection and sterile danger.
Summary
Inflammatory diseases affect over 80 million people worldwide and accompany many diseases of industrialized countries, being the majority of them infection-free conditions. There are few efficient anti-inflammatory drugs to treat chronic inflammation and thus, there is an urgent need to validate novel targets. We now know that innate immunity is the main coordinator and driver of inflammation. Recently, we and others have shown that the activation of purinergic P2X7 receptors (P2X7R) in immune cells is a novel and increasingly validated pathway to initiate inflammation through the activation of the NLRP3 inflammasome and the release of IL-1β and IL-18 cytokines. However, how NLRP3 sense P2X7R activation is not fully understood. Furthermore, extracellular ATP, the physiological P2X7R agonist, is a crucial danger signal released by injured cells, and one of the most important mediators of infection-free inflammation. We have also identified novel signalling roles for P2X7R independent on the NLRP3 inflammasome, including the release of proteases or inflammatory lipids. Therefore, P2X7R has generated increasing interest as a therapeutic target in inflammatory diseases, being drug like P2X7R antagonist in clinical trials to treat inflammatory diseases. However, it is often questioned the functionality of P2X7R in vivo, where it is thought that extracellular ATP levels are below the threshold to activate P2X7R. The overall significance of this proposal relays to elucidate how extracellular ATP controls host-defence in vivo, ultimately depicting P2X7R signalling through and beyond inflammasome activation. We foresee that our results will generate a leading innovative knowledge about in vivo extracellular ATP signalling during the host response to infection and sterile danger.
Max ERC Funding
1 794 948 €
Duration
Start date: 2014-09-01, End date: 2019-08-31
Project acronym DC_Nutrient
Project Investigating nutrients as key determinants of DC-induced CD8 T cell responses
Researcher (PI) David FINLAY
Host Institution (HI) THE PROVOST, FELLOWS, FOUNDATION SCHOLARS & THE OTHER MEMBERS OF BOARD OF THE COLLEGE OF THE HOLY & UNDIVIDED TRINITY OF QUEEN ELIZABETH NEAR DUBLIN
Call Details Consolidator Grant (CoG), LS6, ERC-2017-COG
Summary A new immunoregulatory axis has emerged in recent years demonstrating that cellular metabolism is crucial in controlling immune responses. This regulatory axis is acutely sensitive to nutrients that fuel metabolic pathways and support nutrient sensitive signalling pathways. My recent research demonstrates that nutrients are dynamically controlled and are not equally available to all immune cells. The data shows that activated T cells, clustered around a dendritic cell (DC), can consume the available nutrients, leaving the DC nutrient deprived in vitro. This local regulation of the DC nutrient microenvironment by neighbouring cells has profound effects on DC function and T cell responses. Nutrient deprived DC have altered signalling (decreased mTORC1 activity), increased pro-inflammatory functions (IL12 and costimulatory molecule expression) and induce enhanced T cell responses (proliferation, IFNγ production). However, proving this, particularly in vivo, is a major challenge as the tools to investigate nutrient dynamics within complex microenvironments have not yet been developed. This research programme will generate innovative new technologies to measure the local distribution of glucose, glutamine and leucine (all of which control mTORC1 signalling) to be visualised and quantified. These technologies will pioneer a new era of in vivo nutrient analysis. Nutrient deprivation of antigen presenting DC will then be investigated (using our new technologies) in response to various stimuli within the inflammatory lymph node and correlated to CD8 T cell responses. We will generate state-of-the-art transgenic mice to specifically knock-down nutrient transporters for glucose, glutamine, or leucine in DC to definitively prove that the availability of these nutrients to antigen presenting DC is a key mechanism for controlling CD8 T cells responses. This would be a paradigm shifting discovery that would open new horizons for the study of nutrient-regulated immune responses.
Summary
A new immunoregulatory axis has emerged in recent years demonstrating that cellular metabolism is crucial in controlling immune responses. This regulatory axis is acutely sensitive to nutrients that fuel metabolic pathways and support nutrient sensitive signalling pathways. My recent research demonstrates that nutrients are dynamically controlled and are not equally available to all immune cells. The data shows that activated T cells, clustered around a dendritic cell (DC), can consume the available nutrients, leaving the DC nutrient deprived in vitro. This local regulation of the DC nutrient microenvironment by neighbouring cells has profound effects on DC function and T cell responses. Nutrient deprived DC have altered signalling (decreased mTORC1 activity), increased pro-inflammatory functions (IL12 and costimulatory molecule expression) and induce enhanced T cell responses (proliferation, IFNγ production). However, proving this, particularly in vivo, is a major challenge as the tools to investigate nutrient dynamics within complex microenvironments have not yet been developed. This research programme will generate innovative new technologies to measure the local distribution of glucose, glutamine and leucine (all of which control mTORC1 signalling) to be visualised and quantified. These technologies will pioneer a new era of in vivo nutrient analysis. Nutrient deprivation of antigen presenting DC will then be investigated (using our new technologies) in response to various stimuli within the inflammatory lymph node and correlated to CD8 T cell responses. We will generate state-of-the-art transgenic mice to specifically knock-down nutrient transporters for glucose, glutamine, or leucine in DC to definitively prove that the availability of these nutrients to antigen presenting DC is a key mechanism for controlling CD8 T cells responses. This would be a paradigm shifting discovery that would open new horizons for the study of nutrient-regulated immune responses.
Max ERC Funding
1 995 861 €
Duration
Start date: 2018-05-01, End date: 2023-04-30
Project acronym DevoTed_miR
Project MicroRNA determinants of the balance between effector and regulatory T cells in vivo
Researcher (PI) Bruno Miguel De Carvalho e Silva Santos
Host Institution (HI) INSTITUTO DE MEDICINA MOLECULAR JOAO LOBO ANTUNES
Call Details Consolidator Grant (CoG), LS6, ERC-2014-CoG
Summary T lymphocytes display potent pro- or anti-inflammatory properties, which typically associate with distinct effector (Teff) versus regulatory (Treg) cell subsets. Based on published and our preliminary data showing a major impact of microRNAs on T cell differentiation and (auto)immune pathology, my proposal aims to dissect the miRNA networks that control the balance between Teff and Treg subsets in vivo, in various experimental models of infection and autoimmunity.
We will focus on three critical mediators of T cell functions: interferon-gamma (IFN-g) and interleukin-17A (IL-17), highly pro-inflammatory Teff cytokines; and Foxp3, the transcription factor that confers Treg suppressive properties. To track the activity of these key genes, we will generate a new Ifng/ Il17/ Foxp3 triple reporter mouse, from which we will isolate Teff and Treg subsets to determine their genome-wide miRNA profiles and specific signatures in vivo. We will investigate both natural (thymic-derived and present in naïve mice) and induced (in the periphery upon challenge) Teff and Treg subsets, as they make distinct contributions to the immune response. We will identify miRNAs selectively expressed in Teff (Ifng+ or Il17+) versus Treg (Foxp3+) subsets of various lineages (CD4+, CD8+, gamma-delta or NKT) in each in vivo model; assess whether they are induced during thymic development or upon peripheral activation; and determine the robustness of subset-specific miRNA profiles across various in vivo challenges.
We will then use loss- and gain-of-function strategies to define the individual miRNAs that impact Teff or Treg differentiation and disease pathogenesis; dissect the external cues and intracellular mechanisms that regulate miRNA expression; and identify the mRNA networks controlled by key miRNAs in Teff and Treg differentiation. I expect this project to provide major conceptual and experimental advances towards manipulating miRNAs either to boost immunity or to treat autoimmunity.
Summary
T lymphocytes display potent pro- or anti-inflammatory properties, which typically associate with distinct effector (Teff) versus regulatory (Treg) cell subsets. Based on published and our preliminary data showing a major impact of microRNAs on T cell differentiation and (auto)immune pathology, my proposal aims to dissect the miRNA networks that control the balance between Teff and Treg subsets in vivo, in various experimental models of infection and autoimmunity.
We will focus on three critical mediators of T cell functions: interferon-gamma (IFN-g) and interleukin-17A (IL-17), highly pro-inflammatory Teff cytokines; and Foxp3, the transcription factor that confers Treg suppressive properties. To track the activity of these key genes, we will generate a new Ifng/ Il17/ Foxp3 triple reporter mouse, from which we will isolate Teff and Treg subsets to determine their genome-wide miRNA profiles and specific signatures in vivo. We will investigate both natural (thymic-derived and present in naïve mice) and induced (in the periphery upon challenge) Teff and Treg subsets, as they make distinct contributions to the immune response. We will identify miRNAs selectively expressed in Teff (Ifng+ or Il17+) versus Treg (Foxp3+) subsets of various lineages (CD4+, CD8+, gamma-delta or NKT) in each in vivo model; assess whether they are induced during thymic development or upon peripheral activation; and determine the robustness of subset-specific miRNA profiles across various in vivo challenges.
We will then use loss- and gain-of-function strategies to define the individual miRNAs that impact Teff or Treg differentiation and disease pathogenesis; dissect the external cues and intracellular mechanisms that regulate miRNA expression; and identify the mRNA networks controlled by key miRNAs in Teff and Treg differentiation. I expect this project to provide major conceptual and experimental advances towards manipulating miRNAs either to boost immunity or to treat autoimmunity.
Max ERC Funding
2 000 000 €
Duration
Start date: 2015-07-01, End date: 2020-06-30
