Project acronym 3DBIOLUNG
Project Bioengineering lung tissue using extracellular matrix based 3D bioprinting
Researcher (PI) Darcy WAGNER
Host Institution (HI) LUNDS UNIVERSITET
Country Sweden
Call Details Starting Grant (StG), LS9, ERC-2018-STG
Summary Chronic lung diseases are increasing in prevalence with over 65 million patients worldwide. Lung transplantation remains the only potential option at end-stage disease. Around 4000 patients receive lung transplants annually with more awaiting transplantation, including 1000 patients in Europe. New options to increase available tissue for lung transplantation are desperately needed.
An exciting new research area focuses on generating lung tissue ex vivo using bioengineering approaches. Scaffolds can be generated from synthetic or biologically-derived (acellular) materials, seeded with cells and grown in a bioreactor prior to transplantation. Ideally, scaffolds would be seeded with cells derived from the transplant recipient, thus obviating the need for long-term immunosuppression. However, functional regeneration has yet to be achieved. New advances in 3D printing and 3D bioprinting (when cells are printed) indicate that this once thought of science-fiction concept might finally be mature enough for complex tissues, including lung. 3D bioprinting addresses a number of concerns identified in previous approaches, such as a) patient heterogeneity in acellular human scaffolds, b) anatomical differences in xenogeneic sources, c) lack of biological cues on synthetic materials and d) difficulty in manufacturing the complex lung architecture. 3D bioprinting could be a reproducible, scalable, and controllable approach for generating functional lung tissue.
The aim of this proposal is to use custom 3D bioprinters to generate constructs mimicking lung tissue using an innovative approach combining primary cells, the engineering reproducibility of synthetic materials, and the biologically conductive properties of acellular lung (hybrid). We will 3D bioprint hybrid murine and human lung tissue models and test gas exchange, angiogenesis and in vivo immune responses. This proposal will be a critical first step in demonstrating feasibility of 3D bioprinting lung tissue.
Summary
Chronic lung diseases are increasing in prevalence with over 65 million patients worldwide. Lung transplantation remains the only potential option at end-stage disease. Around 4000 patients receive lung transplants annually with more awaiting transplantation, including 1000 patients in Europe. New options to increase available tissue for lung transplantation are desperately needed.
An exciting new research area focuses on generating lung tissue ex vivo using bioengineering approaches. Scaffolds can be generated from synthetic or biologically-derived (acellular) materials, seeded with cells and grown in a bioreactor prior to transplantation. Ideally, scaffolds would be seeded with cells derived from the transplant recipient, thus obviating the need for long-term immunosuppression. However, functional regeneration has yet to be achieved. New advances in 3D printing and 3D bioprinting (when cells are printed) indicate that this once thought of science-fiction concept might finally be mature enough for complex tissues, including lung. 3D bioprinting addresses a number of concerns identified in previous approaches, such as a) patient heterogeneity in acellular human scaffolds, b) anatomical differences in xenogeneic sources, c) lack of biological cues on synthetic materials and d) difficulty in manufacturing the complex lung architecture. 3D bioprinting could be a reproducible, scalable, and controllable approach for generating functional lung tissue.
The aim of this proposal is to use custom 3D bioprinters to generate constructs mimicking lung tissue using an innovative approach combining primary cells, the engineering reproducibility of synthetic materials, and the biologically conductive properties of acellular lung (hybrid). We will 3D bioprint hybrid murine and human lung tissue models and test gas exchange, angiogenesis and in vivo immune responses. This proposal will be a critical first step in demonstrating feasibility of 3D bioprinting lung tissue.
Max ERC Funding
1 499 975 €
Duration
Start date: 2019-01-01, End date: 2023-12-31
Project acronym 3DPROTEINPUZZLES
Project Shape-directed protein assembly design
Researcher (PI) Lars Ingemar ANDRe
Host Institution (HI) MAX IV Laboratory, Lund University
Country Sweden
Call Details Consolidator Grant (CoG), LS9, ERC-2017-COG
Summary Large protein complexes carry out some of the most complex functions in biology. Such structures are often assembled spontaneously from individual components through the process of self-assembly. If self-assembled protein complexes could be engineered from first principle it would enable a wide range of applications in biomedicine, nanotechnology and materials science. Recently, approaches to rationally design proteins to self-assembly into predefined structures have emerged. The highlight of this work is the design of protein cages that may be engineered into protein containers. However, current approaches for self-assembly design does not result in the assemblies with the required structural complexity to encode many of the sophisticated functions found in nature. To move forward, we have to learn how to engineer protein subunits with more than one designed interface that can assemble into tightly interacting complexes. In this proposal we propose a new protein design paradigm, shape directed protein design, in order to address shortcomings of the current methodology. The proposed method combines geometric shape matching and computational protein design. Using this approach we will de novo design assemblies with a wide variety of structural states, including protein complexes with cyclic and dihedral symmetry as well as icosahedral protein capsids built from novel protein building blocks. To enable these two design challenges we also develop a high-throughput assay to measure assembly stability in vivo that builds on a three-color fluorescent assay. This method will not only facilitate the screening of orders of magnitude more design constructs, but also enable the application of directed evolution to experimentally improve stable and assembly properties of designed containers as well as other designed assemblies.
Summary
Large protein complexes carry out some of the most complex functions in biology. Such structures are often assembled spontaneously from individual components through the process of self-assembly. If self-assembled protein complexes could be engineered from first principle it would enable a wide range of applications in biomedicine, nanotechnology and materials science. Recently, approaches to rationally design proteins to self-assembly into predefined structures have emerged. The highlight of this work is the design of protein cages that may be engineered into protein containers. However, current approaches for self-assembly design does not result in the assemblies with the required structural complexity to encode many of the sophisticated functions found in nature. To move forward, we have to learn how to engineer protein subunits with more than one designed interface that can assemble into tightly interacting complexes. In this proposal we propose a new protein design paradigm, shape directed protein design, in order to address shortcomings of the current methodology. The proposed method combines geometric shape matching and computational protein design. Using this approach we will de novo design assemblies with a wide variety of structural states, including protein complexes with cyclic and dihedral symmetry as well as icosahedral protein capsids built from novel protein building blocks. To enable these two design challenges we also develop a high-throughput assay to measure assembly stability in vivo that builds on a three-color fluorescent assay. This method will not only facilitate the screening of orders of magnitude more design constructs, but also enable the application of directed evolution to experimentally improve stable and assembly properties of designed containers as well as other designed assemblies.
Max ERC Funding
2 325 292 €
Duration
Start date: 2018-06-01, End date: 2023-05-31
Project acronym ADDICTIONCIRCUITS
Project Drug addiction: molecular changes in reward and aversion circuits
Researcher (PI) Nils David Engblom
Host Institution (HI) LINKOPINGS UNIVERSITET
Country Sweden
Call Details Starting Grant (StG), LS5, ERC-2010-StG_20091118
Summary Our affective and motivational state is important for our decisions, actions and quality of life. Many pathological conditions affect this state. For example, addictive drugs are hyperactivating the reward system and trigger a strong motivation for continued drug intake, whereas many somatic and psychiatric diseases lead to an aversive state, characterized by loss of motivation. I will study specific neural circuits and mechanisms underlying reward and aversion, and how pathological signaling in these systems can trigger relapse in drug addiction.
Given the important role of the dopaminergic neurons in the midbrain for many aspects of reward signaling, I will study how synaptic plasticity in these cells, and in their target neurons in the striatum, contribute to relapse in drug seeking. I will also study the circuits underlying aversion. Little is known about these circuits, but my hypothesis is that an important component of aversion is signaled by a specific neuronal population in the brainstem parabrachial nucleus, projecting to the central amygdala. We will test this hypothesis and also determine how this aversion circuit contributes to the persistence of addiction and to relapse.
To dissect this complicated system, I am developing new genetic methods for manipulating and visualizing specific functional circuits in the mouse brain. My unique combination of state-of-the-art competence in transgenics and cutting edge knowledge in the anatomy and functional organization of the circuits behind reward and aversion should allow me to decode these systems, linking discrete circuits to behavior.
Collectively, the results will indicate how signals encoding aversion and reward are integrated to control addictive behavior and they may identify novel avenues for treatment of drug addiction as well as aversion-related symptoms affecting patients with chronic inflammatory conditions and cancer.
Summary
Our affective and motivational state is important for our decisions, actions and quality of life. Many pathological conditions affect this state. For example, addictive drugs are hyperactivating the reward system and trigger a strong motivation for continued drug intake, whereas many somatic and psychiatric diseases lead to an aversive state, characterized by loss of motivation. I will study specific neural circuits and mechanisms underlying reward and aversion, and how pathological signaling in these systems can trigger relapse in drug addiction.
Given the important role of the dopaminergic neurons in the midbrain for many aspects of reward signaling, I will study how synaptic plasticity in these cells, and in their target neurons in the striatum, contribute to relapse in drug seeking. I will also study the circuits underlying aversion. Little is known about these circuits, but my hypothesis is that an important component of aversion is signaled by a specific neuronal population in the brainstem parabrachial nucleus, projecting to the central amygdala. We will test this hypothesis and also determine how this aversion circuit contributes to the persistence of addiction and to relapse.
To dissect this complicated system, I am developing new genetic methods for manipulating and visualizing specific functional circuits in the mouse brain. My unique combination of state-of-the-art competence in transgenics and cutting edge knowledge in the anatomy and functional organization of the circuits behind reward and aversion should allow me to decode these systems, linking discrete circuits to behavior.
Collectively, the results will indicate how signals encoding aversion and reward are integrated to control addictive behavior and they may identify novel avenues for treatment of drug addiction as well as aversion-related symptoms affecting patients with chronic inflammatory conditions and cancer.
Max ERC Funding
1 500 000 €
Duration
Start date: 2010-10-01, End date: 2015-09-30
Project acronym AfricanNeo
Project The African Neolithic: A genetic perspective
Researcher (PI) Carina SCHLEBUSCH
Host Institution (HI) UPPSALA UNIVERSITET
Country Sweden
Call Details Starting Grant (StG), SH6, ERC-2017-STG
Summary The spread of farming practices in various parts of the world had a marked influence on how humans live today and how we are distributed around the globe. Around 10,000 years ago, warmer conditions lead to population increases, coinciding with the invention of farming in several places around the world. Archaeological evidence attest to the spread of these practices to neighboring regions. In many cases this lead to whole continents being converted from hunter-gatherer to farming societies. It is however difficult to see from archaeological records if only the farming culture spread to other places or whether the farming people themselves migrated. Investigating patterns of genetic variation for farming populations and for remaining hunter-gatherer groups can help to resolve questions on population movements co-occurring with the spread of farming practices. It can further shed light on the routes of migration and dates when migrants arrived.
The spread of farming to Europe has been thoroughly investigated in the fields of archaeology, linguistics and genetics, while on other continents these events have been less investigated. In Africa, mainly linguistic and archaeological studies have attempted to elucidate the spread of farming and herding practices. I propose to investigate the movement of farmer and pastoral groups in Africa, by typing densely spaced genome-wide variant positions in a large number of African populations. The data will be used to infer how farming and pastoralism was introduced to various regions, where the incoming people originated from and when these (potential) population movements occurred. Through this study, the Holocene history of Africa will be revealed and placed into a global context of migration, mobility and cultural transitions. Additionally the study will give due credence to one of the largest Neolithic expansion events, the Bantu-expansion, which caused a pronounced change in the demographic landscape of the African continent
Summary
The spread of farming practices in various parts of the world had a marked influence on how humans live today and how we are distributed around the globe. Around 10,000 years ago, warmer conditions lead to population increases, coinciding with the invention of farming in several places around the world. Archaeological evidence attest to the spread of these practices to neighboring regions. In many cases this lead to whole continents being converted from hunter-gatherer to farming societies. It is however difficult to see from archaeological records if only the farming culture spread to other places or whether the farming people themselves migrated. Investigating patterns of genetic variation for farming populations and for remaining hunter-gatherer groups can help to resolve questions on population movements co-occurring with the spread of farming practices. It can further shed light on the routes of migration and dates when migrants arrived.
The spread of farming to Europe has been thoroughly investigated in the fields of archaeology, linguistics and genetics, while on other continents these events have been less investigated. In Africa, mainly linguistic and archaeological studies have attempted to elucidate the spread of farming and herding practices. I propose to investigate the movement of farmer and pastoral groups in Africa, by typing densely spaced genome-wide variant positions in a large number of African populations. The data will be used to infer how farming and pastoralism was introduced to various regions, where the incoming people originated from and when these (potential) population movements occurred. Through this study, the Holocene history of Africa will be revealed and placed into a global context of migration, mobility and cultural transitions. Additionally the study will give due credence to one of the largest Neolithic expansion events, the Bantu-expansion, which caused a pronounced change in the demographic landscape of the African continent
Max ERC Funding
1 500 000 €
Duration
Start date: 2017-11-01, End date: 2022-10-31
Project acronym AGINGSEXDIFF
Project Aging Differently: Understanding Sex Differences in Reproductive, Demographic and Functional Senescence
Researcher (PI) Alexei Maklakov
Host Institution (HI) UPPSALA UNIVERSITET
Country Sweden
Call Details Starting Grant (StG), LS8, ERC-2010-StG_20091118
Summary Sex differences in life span and aging are ubiquitous across the animal kingdom and represent a
long-standing challenge in evolutionary biology. In most species, including humans, sexes differ not
only in how long they live and when they start to senesce, but also in how they react to
environmental interventions aimed at prolonging their life span or decelerating the onset of aging.
Therefore, sex differences in life span and aging have important implications beyond the questions
posed by fundamental science. Both evolutionary reasons and medical implications of sex
differences in demographic, reproductive and physiological senescence are and will be crucial
targets of present and future research in the biology of aging. Here I propose a two-step approach
that can provide a significant breakthrough in our understanding of the biological basis of sex
differences in aging. First, I propose to resolve the age-old conundrum regarding the role of sexspecific
mortality rate in sex differences in aging by developing a series of targeted experimental
evolution studies in a novel model organism – the nematode, Caenorhabditis remanei. Second, I
address the role of intra-locus sexual conflict in the evolution of aging by combining novel
methodology from nutritional ecology – the Geometric Framework – with artificial selection
approach using the cricket Teleogryllus commodus and the fruitfly Drosophila melanogaster. I will
directly test the hypothesis that intra-locus sexual conflict mediates aging by restricting the
adaptive evolution of diet choice. By combining techniques from evolutionary biology and
nutritional ecology, this proposal will raise EU’s profile in integrative research, and contribute to
the training of young scientists in this rapidly developing field.
Summary
Sex differences in life span and aging are ubiquitous across the animal kingdom and represent a
long-standing challenge in evolutionary biology. In most species, including humans, sexes differ not
only in how long they live and when they start to senesce, but also in how they react to
environmental interventions aimed at prolonging their life span or decelerating the onset of aging.
Therefore, sex differences in life span and aging have important implications beyond the questions
posed by fundamental science. Both evolutionary reasons and medical implications of sex
differences in demographic, reproductive and physiological senescence are and will be crucial
targets of present and future research in the biology of aging. Here I propose a two-step approach
that can provide a significant breakthrough in our understanding of the biological basis of sex
differences in aging. First, I propose to resolve the age-old conundrum regarding the role of sexspecific
mortality rate in sex differences in aging by developing a series of targeted experimental
evolution studies in a novel model organism – the nematode, Caenorhabditis remanei. Second, I
address the role of intra-locus sexual conflict in the evolution of aging by combining novel
methodology from nutritional ecology – the Geometric Framework – with artificial selection
approach using the cricket Teleogryllus commodus and the fruitfly Drosophila melanogaster. I will
directly test the hypothesis that intra-locus sexual conflict mediates aging by restricting the
adaptive evolution of diet choice. By combining techniques from evolutionary biology and
nutritional ecology, this proposal will raise EU’s profile in integrative research, and contribute to
the training of young scientists in this rapidly developing field.
Max ERC Funding
1 391 904 €
Duration
Start date: 2010-12-01, End date: 2016-05-31
Project acronym Allelic Regulation
Project Revealing Allele-level Regulation and Dynamics using Single-cell Gene Expression Analyses
Researcher (PI) Thore Rickard Hakan Sandberg
Host Institution (HI) KAROLINSKA INSTITUTET
Country Sweden
Call Details Consolidator Grant (CoG), LS2, ERC-2014-CoG
Summary As diploid organisms inherit one gene copy from each parent, a gene can be expressed from both alleles (biallelic) or from only one allele (monoallelic). Although transcription from both alleles is detected for most genes in cell population experiments, little is known about allele-specific expression in single cells and its phenotypic consequences. To answer fundamental questions about allelic transcription heterogeneity in single cells, this research program will focus on single-cell transcriptome analyses with allelic-origin resolution. To this end, we will investigate both clonally stable and dynamic random monoallelic expression across a large number of cell types, including cells from embryonic and adult stages. This research program will be accomplished with the novel single-cell RNA-seq method developed within my lab to obtain quantitative, genome-wide gene expression measurement. To distinguish between mitotically stable and dynamic patterns of allelic expression, we will analyze large numbers a clonally related cells per cell type, from both primary cultures (in vitro) and using transgenic models to obtain clonally related cells in vivo.
The biological significance of the research program is first an understanding of allelic transcription, including the nature and extent of random monoallelic expression across in vivo tissues and cell types. These novel insights into allelic transcription will be important for an improved understanding of how variable phenotypes (e.g. incomplete penetrance and variable expressivity) can arise in genetically identical individuals. Additionally, the single-cell transcriptome analyses of clonally related cells in vivo will provide unique insights into the clonality of gene expression per se.
Summary
As diploid organisms inherit one gene copy from each parent, a gene can be expressed from both alleles (biallelic) or from only one allele (monoallelic). Although transcription from both alleles is detected for most genes in cell population experiments, little is known about allele-specific expression in single cells and its phenotypic consequences. To answer fundamental questions about allelic transcription heterogeneity in single cells, this research program will focus on single-cell transcriptome analyses with allelic-origin resolution. To this end, we will investigate both clonally stable and dynamic random monoallelic expression across a large number of cell types, including cells from embryonic and adult stages. This research program will be accomplished with the novel single-cell RNA-seq method developed within my lab to obtain quantitative, genome-wide gene expression measurement. To distinguish between mitotically stable and dynamic patterns of allelic expression, we will analyze large numbers a clonally related cells per cell type, from both primary cultures (in vitro) and using transgenic models to obtain clonally related cells in vivo.
The biological significance of the research program is first an understanding of allelic transcription, including the nature and extent of random monoallelic expression across in vivo tissues and cell types. These novel insights into allelic transcription will be important for an improved understanding of how variable phenotypes (e.g. incomplete penetrance and variable expressivity) can arise in genetically identical individuals. Additionally, the single-cell transcriptome analyses of clonally related cells in vivo will provide unique insights into the clonality of gene expression per se.
Max ERC Funding
1 923 060 €
Duration
Start date: 2015-07-01, End date: 2020-12-31
Project acronym ANALYTICAL SOCIOLOGY
Project Analytical Sociology: Theoretical Developments and Empirical Research
Researcher (PI) Mats Peter Hedstroem
Host Institution (HI) LINKOPINGS UNIVERSITET
Country Sweden
Call Details Advanced Grant (AdG), SH2, ERC-2012-ADG_20120411
Summary This proposal outlines a highly ambitious and path-breaking research program. Through a tightly integrated package of basic theoretical work, strategic empirical research projects, international workshops, and a large number of publications in leading journals, the research program seeks to move sociology in a more analytical direction.
One part of the research program focuses on the epistemological and methodological foundations of analytical sociology, an approach to sociological theory and research that currently receives considerable attention in the international scholarly community. This work will be organized around two core themes: (1) the principles of mechanism-based explanations and (2) the micro-macro link.
The empirical research analyzes in great detail the ethnic, gender, and socio-economic segregation of key interaction domains in Sweden using the approach of analytical sociology. The interaction domains focused upon are schools, workplaces and neighborhoods; domains where people spend a considerable part of their time, where much of the social interaction between people takes place, where identities are formed, and where important resources are distributed.
Large-scale longitudinal micro data on the entire Swedish population, unique longitudinal data on social networks within school classes, and various agent-based simulation techniques, are used to better understand the processes through which schools, workplaces and neighborhoods become segregated along various dimensions, how the domains interact with one another, and how the structure and extent of segregation affects diverse social and economic outcomes.
Summary
This proposal outlines a highly ambitious and path-breaking research program. Through a tightly integrated package of basic theoretical work, strategic empirical research projects, international workshops, and a large number of publications in leading journals, the research program seeks to move sociology in a more analytical direction.
One part of the research program focuses on the epistemological and methodological foundations of analytical sociology, an approach to sociological theory and research that currently receives considerable attention in the international scholarly community. This work will be organized around two core themes: (1) the principles of mechanism-based explanations and (2) the micro-macro link.
The empirical research analyzes in great detail the ethnic, gender, and socio-economic segregation of key interaction domains in Sweden using the approach of analytical sociology. The interaction domains focused upon are schools, workplaces and neighborhoods; domains where people spend a considerable part of their time, where much of the social interaction between people takes place, where identities are formed, and where important resources are distributed.
Large-scale longitudinal micro data on the entire Swedish population, unique longitudinal data on social networks within school classes, and various agent-based simulation techniques, are used to better understand the processes through which schools, workplaces and neighborhoods become segregated along various dimensions, how the domains interact with one another, and how the structure and extent of segregation affects diverse social and economic outcomes.
Max ERC Funding
1 745 098 €
Duration
Start date: 2013-03-01, End date: 2018-02-28
Project acronym ARTSILK
Project Novel approaches to the generation of artificial spider silk superfibers
Researcher (PI) Anna RISING
Host Institution (HI) KAROLINSKA INSTITUTET
Country Sweden
Call Details Consolidator Grant (CoG), LS9, ERC-2018-COG
Summary Spider silk is Nature’s high performance material that has the potential to revolutionize the materials industry. However, production and spinning of artificial spider silk fibers are challenging, and current methods to produce silk fibers include denaturing conditions which prevent the silk proteins from assembling into fibers in the same complex way as native silk proteins do. In order to fulfill the potential of spider silk we need to increase our understanding of the silk formation process and decipher how protein folding and interactions relate to mechanical properties of the resulting silk fiber. Recent insights into the physiology and molecular mechanisms of the spinning process has made it possible to develop a biomimetic artificial spider silk spinning device (see our publications Andersson et al. Nat Chem Biol. 2017; Otikovs et al. Angew Chemie Int Engl Ed. 2017). We are, for the first time, able to spin artificial silk fibers in which the proteins adopt correct secondary, tertiary and quaternary structures.
The overall objective of ARTSILK is to build on these recent technical leaps and use state-of-the-art technologies to generate artificial silk fibers that are equal or superior to native spider silk in terms of toughness and tensile strength.
To reach the overall objective we will use the recently mapped spider genome, protein engineering and single cell RNA (ScRNA) sequencing to design novel silk proteins for fiber production. We will also study the relationship between protein secondary structure formation and fiber mechanical properties in order to decipher the ques that determine mechanical properties of the fiber. This knowledge will be important also for the basic understanding of how soluble proteins covert into b-sheet rich fibrils in, e.g., Alzheimer’s disease. Finally, we will use microfluidic chips to engineer the next generation spinning device and 3D-printing techniques to make reproducible three-dimensional structures of spider silk.
Summary
Spider silk is Nature’s high performance material that has the potential to revolutionize the materials industry. However, production and spinning of artificial spider silk fibers are challenging, and current methods to produce silk fibers include denaturing conditions which prevent the silk proteins from assembling into fibers in the same complex way as native silk proteins do. In order to fulfill the potential of spider silk we need to increase our understanding of the silk formation process and decipher how protein folding and interactions relate to mechanical properties of the resulting silk fiber. Recent insights into the physiology and molecular mechanisms of the spinning process has made it possible to develop a biomimetic artificial spider silk spinning device (see our publications Andersson et al. Nat Chem Biol. 2017; Otikovs et al. Angew Chemie Int Engl Ed. 2017). We are, for the first time, able to spin artificial silk fibers in which the proteins adopt correct secondary, tertiary and quaternary structures.
The overall objective of ARTSILK is to build on these recent technical leaps and use state-of-the-art technologies to generate artificial silk fibers that are equal or superior to native spider silk in terms of toughness and tensile strength.
To reach the overall objective we will use the recently mapped spider genome, protein engineering and single cell RNA (ScRNA) sequencing to design novel silk proteins for fiber production. We will also study the relationship between protein secondary structure formation and fiber mechanical properties in order to decipher the ques that determine mechanical properties of the fiber. This knowledge will be important also for the basic understanding of how soluble proteins covert into b-sheet rich fibrils in, e.g., Alzheimer’s disease. Finally, we will use microfluidic chips to engineer the next generation spinning device and 3D-printing techniques to make reproducible three-dimensional structures of spider silk.
Max ERC Funding
2 000 000 €
Duration
Start date: 2019-05-01, End date: 2024-04-30
Project acronym ASTRODYN
Project Astrophysical Dynamos
Researcher (PI) Axel Brandenburg
Host Institution (HI) KUNGLIGA TEKNISKA HOEGSKOLAN
Country Sweden
Call Details Advanced Grant (AdG), PE9, ERC-2008-AdG
Summary Magnetic fields in stars, planets, accretion discs, and galaxies are believed to be the result of a dynamo process converting kinetic energy into magnetic energy. This work focuses on the solar dynamo, but dynamos in other astrophysical systems will also be addressed. In particular, direct high-resolution three-dimensional simulations are used to understand particular aspects of the solar dynamo and ultimately to simulate the solar dynamo as a whole. Phenomenological approaches will be avoided in favor of obtaining rigorous results. A major problem is catastrophic quenching, i.e. the decline of dynamo effects in inverse proportion to the magnetic Reynolds number, which is huge. Tremendous advances have been made in the last few years since the cause of catastrophic quenching in dynamos has been understood in terms of magnetic helicity evolution. The numerical tools are now in place to allow for magnetic helicity fluxes via coronal mass ejections, thus alleviating catastrophic quenching. This work employs simulations in spherical shells, augmented by Cartesian simulations in special cases. The roles of the near-surface shear layer, the tachocline, as well as pumping in the bulk of the convection zone are to be clarified. The Pencil Code will be used for most applications. The code is third order in time and sixth order in space and is used for solving the hydromagnetic equations. It is a public domain code developed by roughly 20 scientists world wide and maintained under an a central versioning system at Nordita. Automatic nightly tests of currently 30 applications ensure the integrity of the code. It is used for a wide range of applications and may include the effects of radiation, self-gravity, dust, chemistry, variable ionization, cosmic rays, in addition to those of magnetohydrodynamics. The code with its infrastructure offers a good opportunity for individuals within a broad group of people to develop new tools that may automatically be useful to others.
Summary
Magnetic fields in stars, planets, accretion discs, and galaxies are believed to be the result of a dynamo process converting kinetic energy into magnetic energy. This work focuses on the solar dynamo, but dynamos in other astrophysical systems will also be addressed. In particular, direct high-resolution three-dimensional simulations are used to understand particular aspects of the solar dynamo and ultimately to simulate the solar dynamo as a whole. Phenomenological approaches will be avoided in favor of obtaining rigorous results. A major problem is catastrophic quenching, i.e. the decline of dynamo effects in inverse proportion to the magnetic Reynolds number, which is huge. Tremendous advances have been made in the last few years since the cause of catastrophic quenching in dynamos has been understood in terms of magnetic helicity evolution. The numerical tools are now in place to allow for magnetic helicity fluxes via coronal mass ejections, thus alleviating catastrophic quenching. This work employs simulations in spherical shells, augmented by Cartesian simulations in special cases. The roles of the near-surface shear layer, the tachocline, as well as pumping in the bulk of the convection zone are to be clarified. The Pencil Code will be used for most applications. The code is third order in time and sixth order in space and is used for solving the hydromagnetic equations. It is a public domain code developed by roughly 20 scientists world wide and maintained under an a central versioning system at Nordita. Automatic nightly tests of currently 30 applications ensure the integrity of the code. It is used for a wide range of applications and may include the effects of radiation, self-gravity, dust, chemistry, variable ionization, cosmic rays, in addition to those of magnetohydrodynamics. The code with its infrastructure offers a good opportunity for individuals within a broad group of people to develop new tools that may automatically be useful to others.
Max ERC Funding
2 220 000 €
Duration
Start date: 2009-02-01, End date: 2014-01-31
Project acronym B-DOMINANCE
Project B Cell Immunodominance in Antiviral Immunity
Researcher (PI) Davide Angeletti
Host Institution (HI) GOETEBORGS UNIVERSITET
Country Sweden
Call Details Starting Grant (StG), LS6, ERC-2019-STG
Summary This proposal aims at understanding how B cell specificity and immunodominance shape primary and secondary humoral responses to influenza A virus. Influenza A virus is a relevant human pathogen causing a considerable yearly death toll and economic burden to society. Immunodominance is a major driving force of adaptive immunity and defines the hierarchical recognition of epitopes on the same antigen. Previous studies analysing B cell dynamics in primary and secondary responses have been mainly focusing on simple antigens and competition between B cell clones of the same family. Investigation using complex antigens and examining interclonal competition are surprisingly scarce. Influenza hemagglutinin (HA) is a prime candidate to study immunodominance in B cells. I have generated a set of mutant viruses that will allow for an unprecedented investigation into immunodominance and B cell interclonal competition in primary and secondary responses. These viruses can be used to isolate and enumerate antibody and B cells specific for different epitopes on the same complex antigen (HA). I will use these unique tools in combination with state-of-the-art immunological methods, multi-colour flow cytometry and single cells RNA sequencing paired with B cell receptor sequencing to gain fundamental insights into B cell regulation and anti-viral humoral responses. I will i) study the link between B cell receptor characteristics, specificity and B cell fate decisions in primary responses, ii) characterize the relative contribution of pre-existing B cells, serum antibodies and CD4 T cells for immunodominance of secondary responses, iii) define immunodominance in human individuals, repeatedly exposed to influenza virus. I expect this project to critically improve our understanding of basic B cell biology with the long-term benefit of improving current vaccination against variable viral pathogens.
Summary
This proposal aims at understanding how B cell specificity and immunodominance shape primary and secondary humoral responses to influenza A virus. Influenza A virus is a relevant human pathogen causing a considerable yearly death toll and economic burden to society. Immunodominance is a major driving force of adaptive immunity and defines the hierarchical recognition of epitopes on the same antigen. Previous studies analysing B cell dynamics in primary and secondary responses have been mainly focusing on simple antigens and competition between B cell clones of the same family. Investigation using complex antigens and examining interclonal competition are surprisingly scarce. Influenza hemagglutinin (HA) is a prime candidate to study immunodominance in B cells. I have generated a set of mutant viruses that will allow for an unprecedented investigation into immunodominance and B cell interclonal competition in primary and secondary responses. These viruses can be used to isolate and enumerate antibody and B cells specific for different epitopes on the same complex antigen (HA). I will use these unique tools in combination with state-of-the-art immunological methods, multi-colour flow cytometry and single cells RNA sequencing paired with B cell receptor sequencing to gain fundamental insights into B cell regulation and anti-viral humoral responses. I will i) study the link between B cell receptor characteristics, specificity and B cell fate decisions in primary responses, ii) characterize the relative contribution of pre-existing B cells, serum antibodies and CD4 T cells for immunodominance of secondary responses, iii) define immunodominance in human individuals, repeatedly exposed to influenza virus. I expect this project to critically improve our understanding of basic B cell biology with the long-term benefit of improving current vaccination against variable viral pathogens.
Max ERC Funding
1 481 697 €
Duration
Start date: 2019-12-01, End date: 2024-11-30