Oliver Burton | The Babraham Institute (original) (raw)

Papers by Oliver Burton

Research paper thumbnail of A microbiota signature associated with experimental food allergy promotes allergic sensitization and anaphylaxis

Journal of Allergy and Clinical Immunology, 2013

Background-Commensal microbiota play a critical role in maintaining oral tolerance. The effect of... more Background-Commensal microbiota play a critical role in maintaining oral tolerance. The effect of food allergy on the gut microbial ecology remains unknown. Objective-We sought to establish the composition of the gut microbiota in experimental food allergy and its role in disease pathogenesis. Methods-Food allergy-prone mice with a gain-of-function mutation in the IL-4 receptor α chain (Il4raF709) and wild-type (WT) control animals were subjected to oral sensitization with chicken egg ovalbumin (OVA). Enforced tolerance was achieved by using allergen-specific regulatory T (Treg) cells. Community structure analysis of gut microbiota was performed by using a high-density 16S rDNA oligonucleotide microarrays (PhyloChip) and massively parallel pyrosequencing of 16S rDNA amplicons. Results-OVA-sensitized Il4raF709 mice exhibited a specific microbiota signature characterized by coordinate changes in the abundance of taxa of several bacterial families,

Research paper thumbnail of A microbiota signature associated with experimental food allergy promotes allergic sensitization and anaphylaxis

Journal of Allergy and Clinical Immunology, 2013

Background-Commensal microbiota play a critical role in maintaining oral tolerance. The effect of... more Background-Commensal microbiota play a critical role in maintaining oral tolerance. The effect of food allergy on the gut microbial ecology remains unknown. Objective-We sought to establish the composition of the gut microbiota in experimental food allergy and its role in disease pathogenesis. Methods-Food allergy-prone mice with a gain-of-function mutation in the IL-4 receptor α chain (Il4raF709) and wild-type (WT) control animals were subjected to oral sensitization with chicken egg ovalbumin (OVA). Enforced tolerance was achieved by using allergen-specific regulatory T (Treg) cells. Community structure analysis of gut microbiota was performed by using a high-density 16S rDNA oligonucleotide microarrays (PhyloChip) and massively parallel pyrosequencing of 16S rDNA amplicons. Results-OVA-sensitized Il4raF709 mice exhibited a specific microbiota signature characterized by coordinate changes in the abundance of taxa of several bacterial families,

Research paper thumbnail of A booster dose enhances immunogenicity of the COVID-19 vaccine candidate ChAdOx1 nCoV-19 in aged mice

The spread of SARS-CoV-2 has caused a global pandemic that has affected almost every aspect of hu... more The spread of SARS-CoV-2 has caused a global pandemic that has affected almost every aspect of human life. The development of an effective COVID-19 vaccine could limit the morbidity and mortality caused by infection, and may enable the relaxation of social distancing measures. Age is one of the most significant risk factors for poor health outcomes after SARS-CoV-2 infection, therefore it is desirable that any new vaccine candidates should elicit a robust immune response in older adults. Here, we test the immunogenicity of the adenoviral vectored vaccine ChAdOx1 nCoV-19 (AZD-1222) in aged mice. We find that a single dose of this vaccine induces cellular and humoral immunity in aged mice, but at a reduced magnitude than in younger adult mice. Furthermore, we report that a second dose enhances the immune response to this vaccine in aged mice, indicating that a primeboost strategy may be a rational approach to enhance immunogenicity in older persons.

Research paper thumbnail of An open resource for T cell phenotype changes in COVID-19 identifies IL-10-producing regulatory T cells as characteristic of severe cases

The pandemic spread of the novel coronavirus SARS-CoV-2 is due, in part, to the immunological pro... more The pandemic spread of the novel coronavirus SARS-CoV-2 is due, in part, to the immunological properties of the host-viral interaction. The clinical presentation varies greatly from individual to individual, with asymptomatic carriers, mild to moderate-presenting patients and severely affected patients. Variation in immune response to SARS-CoV-2 may underlie this clinical variation. Using a high dimensional systems immunology platform we have analysed the peripheral blood compartment of 6 healthy individuals, 23 mild-to-moderate COVID-19 patients and 20 severe COVID-19 patients. We identify distinct immunological signatures in the peripheral blood of the mild-to-moderate and severe COVID-19 patients, including T cell lymphopenia, more consistent with peripheral hypo- than hyper-immune activation. Unique to the severe COVID-19 cases was a large increase in the proportion of IL-10-secreting regulatory T cells, a lineage known to possess anti-inflammatory properties in the lung. Annota...

Research paper thumbnail of Mice Deficient in Nucleoporin Nup210 Develop Peripheral T Cell Alterations

Research paper thumbnail of Stem-cell-derived human microglia transplanted in mouse brain to study human disease

Research paper thumbnail of Insufficient IL-10 Production as a Mechanism Underlying the Pathogenesis of Systemic Juvenile Idiopathic Arthritis

The Journal of Immunology

Research paper thumbnail of Mechanical Skin Injury Promotes Food Anaphylaxis by Driving Intestinal Mast Cell Expansion

Research paper thumbnail of Stem cell derived human microglia transplanted in mouse brain to study genetic risk of Alzheimer's Disease

Genetics highlight the central role of microglia in Alzheimer's disease but at least 36% of A... more Genetics highlight the central role of microglia in Alzheimer's disease but at least 36% of AD-risk genes lack good mouse orthologues. Here, we show that embryonic stem cell (ESC)-derived human microglia successfully engraft the mouse brain and recapitulate transcriptionally primary human microglia derived from human surgical samples. Upon exposure to oligomeric Aβ a wide range of AD-risk genes are expressed that are not readily studied in current mouse models for AD. This work provides a unique humanized animal model that will allow elucidating the role of genetic risk in the pathogenesis of AD.

Research paper thumbnail of NFIL3 mutations alter immune homeostasis and sensitise for arthritis pathology

Annals of the rheumatic diseases, Jan 14, 2018

is a key immunological transcription factor, with knockout mice studies identifying functional ro... more is a key immunological transcription factor, with knockout mice studies identifying functional roles in multiple immune cell types. Despite the importance of NFIL3, little is known about its function in humans. Here, we characterised a kindred of two monozygotic twin girls with juvenile idiopathic arthritis at the genetic and immunological level, using whole exome sequencing, single cell sequencing and flow cytometry. Parallel studies were performed in a mouse model. The patients inherited a novel p.M170I in NFIL3 from each of the parents. The mutant form of NFIL3 demonstrated reduced stability in vitro. The potential contribution of this mutation to arthritis susceptibility was demonstrated through a preclinical model, where Nfil3-deficient mice upregulated IL-1β production, with more severe arthritis symptoms on disease induction. Single cell sequencing of patient blood quantified the transcriptional dysfunctions present across the peripheral immune system, converging on IL-1β as ...

Research paper thumbnail of {"__content__"=>"The Long Non-coding RNA Anticipates Foxp3 Expression in Regulatory T Cells.", "i"=>{"__content__"=>"Flatr"}}

Frontiers in immunology, 2018

Mammalian genomes encode a plethora of long non-coding RNA (lncRNA). These transcripts are though... more Mammalian genomes encode a plethora of long non-coding RNA (lncRNA). These transcripts are thought to regulate gene expression, influencing biological processes from development to pathology. Results from the few lncRNA that have been studied in the context of the immune system have highlighted potentially critical functions as network regulators. Here we explored the nature of the lncRNA transcriptome in regulatory T cells (Tregs), a subset of CD4 T cells required to establish and maintain immunological self-tolerance. The identified Treg lncRNA transcriptome showed distinct differences from that of non-regulatory CD4 T cells, with evidence of direct shaping of the lncRNA transcriptome by Foxp3, the master transcription factor driving the distinct mRNA profile of Tregs. Treg lncRNA changes were disproportionally reversed in the absence of Foxp3, with an enrichment for colocalisation with Foxp3 DNA binding sites, indicating a direct coordination of transcription by Foxp3 independent...

Research paper thumbnail of Tissue-Specific Expression of the Low-Affinity IgG Receptor, FcγRIIb, on Human Mast Cells

Frontiers in immunology, 2018

Immediate hypersensitivity reactions are induced by the interaction of allergens with specific Ig... more Immediate hypersensitivity reactions are induced by the interaction of allergens with specific IgE antibodies bound FcεRI to mast cells and basophils. While these specific IgE antibodies are needed to trigger such reactions, not all individuals harboring IgE exhibit symptoms of allergy. The lack of responsiveness seen in some subjects correlates with the presence of IgG antibodies of the same specificity. In cell culture studies and animal models of food allergy and anaphylaxis such IgG antibodies have been shown to exert suppression FcγRIIb. However, the reported absence of this inhibitory receptor on primary mast cells derived from human skin has raised questions about the role of IgG-mediated inhibition of immediate hypersensitivity in human subjects. Here, we tested the hypothesis that mast cell FcγRIIb expression might be tissue specific. Utilizing a combination of flow cytometry, quantitative PCR, and immunofluorescence staining of mast cells derived from the tissues of humani...

Research paper thumbnail of Phenotype molding of stromal cells in the lung tumor microenvironment

Nature medicine, Jan 9, 2018

Cancer cells are embedded in the tumor microenvironment (TME), a complex ecosystem of stromal cel... more Cancer cells are embedded in the tumor microenvironment (TME), a complex ecosystem of stromal cells. Here, we present a 52,698-cell catalog of the TME transcriptome in human lung tumors at single-cell resolution, validated in independent samples where 40,250 additional cells were sequenced. By comparing with matching non-malignant lung samples, we reveal a highly complex TME that profoundly molds stromal cells. We identify 52 stromal cell subtypes, including novel subpopulations in cell types hitherto considered to be homogeneous, as well as transcription factors underlying their heterogeneity. For instance, we discover fibroblasts expressing different collagen sets, endothelial cells downregulating immune cell homing and genes coregulated with established immune checkpoint transcripts and correlating with T-cell activity. By assessing marker genes for these cell subtypes in bulk RNA-sequencing data from 1,572 patients, we illustrate how these correlate with survival, while immunohi...

Research paper thumbnail of IL-4 production by group 2 innate lymphoid cells promotes food allergy by blocking regulatory T-cell function

Journal of Allergy and Clinical Immunology, 2016

Food allergy is a major health issue, but its pathogenesis remains obscure. Group 2 innate lympho... more Food allergy is a major health issue, but its pathogenesis remains obscure. Group 2 innate lymphoid cells (ILC2s) promote allergic inflammation. However their role in food allergy is largely unknown. We sought to investigate the role of ILC2s in food allergy. Food allergy-prone mice with a gain-of-function mutation in the IL-4 receptor α chain (Il4raF709) were orally sensitized with food allergens, and the ILC2 compartment was analyzed. The requirement for ILC2s in food allergy was investigated by using Il4raF709, IL-33 receptor-deficient (Il1rl1(-/-)), IL-13-deficient (Il13(-/-)), and IL-4-deficient (Il4(-/-)) mice and by adoptive transfer of in vitro-expanded ILC2s. Direct effects of ILC2s on regulatory T (Treg) cells and mast cells were analyzed in coculture experiments. Treg cell control of ILC2s was assessed in vitro and in vivo. Il4raF709 mice with food allergy exhibit increased numbers of ILC2s. IL-4 secretion by ILC2s contributes to the allergic response by reducing allergen-specific Treg cell and activating mast cell counts. IL-33 receptor deficiency in Il4raF709 Il1rl1(-/-) mice protects against allergen sensitization and anaphylaxis while reducing ILC2 induction. Adoptive transfer of wild-type and Il13(-/-) but not Il4(-/-) ILC2s restored sensitization in Il4raF709 Il1rl1(-/-) mice. Treg cells suppress ILC2s in vitro and in vivo. IL-4 production by IL-33-stimulated ILC2s blocks the generation of allergen-specific Treg cells and favors food allergy. Strategies to block ILC2 activation or the IL-33/IL-33 receptor pathway can lead to innovative therapies in the treatment of food allergy.

Research paper thumbnail of A humanized mouse model of anaphylactic peanut allergy

Journal of Allergy and Clinical Immunology, 2016

Food allergy is a growing health problem with very limited treatment options. Investigation of th... more Food allergy is a growing health problem with very limited treatment options. Investigation of the immunologic pathways underlying allergic sensitization to foods in humans has been greatly constrained by the limited availability of intestinal tissue and gut-resident immune cells. Although mouse models have offered insights into pathways of food sensitization, differences between rodent and human immune physiology limit the extension of these findings to our understanding of human disease. We sought to develop a strategy for the generation of mice with humanized adaptive immune systems, complete with tissue engraftment by human mast cells that are competent to mount specific IgE-mediated responses and drive systemic anaphylaxis on ingestion challenge. Nonobese diabetic severe combined immunodeficient mice lacking the cytokine receptor common gamma chain (γc(-/-)) and carrying a human stem cell factor transgene were engrafted with human hematopoietic stem cells. The impact of peanut (PN) feeding and IgE neutralization on the development of immune responses, mast cell homeostasis, and anaphylactic food allergy was assessed in these animals. Humanized nonobese diabetic severe combined immunodeficient common gamma chain-deficient stem cell factor (huNSG) mice exhibited robust engraftment with functional human T and B lymphocytes and human mast cells were found in significant numbers in their tissues, including the intestinal mucosa. Following gavage feeding with PN, they mounted specific antibody responses, including PN-specific IgE. When enterally challenged with PN, they exhibited mast-cell-mediated systemic anaphylaxis, as indicated by hypothermia and increases in plasma tryptase levels. Anti-IgE (omalizumab) treatment ablated this anaphylactic response. huNSG mice provide a novel tool for studying food allergy and IgE-mediated anaphylaxis.

Research paper thumbnail of Oral immunotherapy induces IgG antibodies that act through Fc?RIIb to suppress IgE-mediated hypersensitivity

Data Revues 00916749 Unassign S0091674914008033, Jul 18, 2014

Food-induced anaphylaxis is triggered by specific IgE antibodies. Paradoxically, some subjects wi... more Food-induced anaphylaxis is triggered by specific IgE antibodies. Paradoxically, some subjects with significant IgE levels can ingest allergenic foods without incident. Similarly, subjects completing oral immunotherapy (OIT) tolerate food challenges despite persistent high-titer food-specific IgE. We sought to test whether IgG antibodies induced by food immunotherapy prevent food-induced anaphylaxis and whether this occurs through the inhibitory receptor FcγRIIb. Food allergy-susceptible Il4raF709 mice were enterally sensitized to ovalbumin (OVA). Similarly sensitized IgE-deficient (IgE(-/-)) Il4raF709 mice, which can ingest OVA without anaphylaxis, were subjected to a high-dose enteral OVA desensitization protocol (OIT). Sera from both groups were tested for the ability to activate or inhibit bone marrow mast cells (BMMCs) exposed to allergen or to passively transfer allergy to naive hosts. In parallel experiments sera obtained from patients with peanut allergy before and after undergoing OIT were interrogated for their ability to enhance or suppress peanut-induced activation in an indirect assay by using basophils from nonallergic donors. Il4raF709 mice exhibited strong OVA-specific IgE responses. Their sera efficiently sensitized BMMCs for activation by antigen challenge. Sera from Il4raF709/IgE(-/-) mice subjected to OVA OIT suppressed BMMC responses. This inhibition was IgG mediated and FcγRIIb dependent. Similarly, pre-OIT but not post-OIT sera from patients efficiently sensitized basophils for peanut-induced activation. IgG antibodies in post-OIT sera suppressed basophil activation by pre-OIT sera. This inhibition was blocked by antibodies against FcγRII. Food-specific IgG antibodies, such as those induced during OIT, inhibit IgE-mediated reactions. Strategies that favor IgG responses might prove useful in the management of food allergy.

Research paper thumbnail of Parasite modulation of autoimmune diseases

Research paper thumbnail of Oral immunotherapy induces IgG antibodies that act through Fc?RIIb to suppress IgE-mediated hypersensitivity

Data Revues 00916749 Unassign S0091674914008033, Jul 18, 2014

Food-induced anaphylaxis is triggered by specific IgE antibodies. Paradoxically, some subjects wi... more Food-induced anaphylaxis is triggered by specific IgE antibodies. Paradoxically, some subjects with significant IgE levels can ingest allergenic foods without incident. Similarly, subjects completing oral immunotherapy (OIT) tolerate food challenges despite persistent high-titer food-specific IgE. We sought to test whether IgG antibodies induced by food immunotherapy prevent food-induced anaphylaxis and whether this occurs through the inhibitory receptor FcγRIIb. Food allergy-susceptible Il4raF709 mice were enterally sensitized to ovalbumin (OVA). Similarly sensitized IgE-deficient (IgE(-/-)) Il4raF709 mice, which can ingest OVA without anaphylaxis, were subjected to a high-dose enteral OVA desensitization protocol (OIT). Sera from both groups were tested for the ability to activate or inhibit bone marrow mast cells (BMMCs) exposed to allergen or to passively transfer allergy to naive hosts. In parallel experiments sera obtained from patients with peanut allergy before and after undergoing OIT were interrogated for their ability to enhance or suppress peanut-induced activation in an indirect assay by using basophils from nonallergic donors. Il4raF709 mice exhibited strong OVA-specific IgE responses. Their sera efficiently sensitized BMMCs for activation by antigen challenge. Sera from Il4raF709/IgE(-/-) mice subjected to OVA OIT suppressed BMMC responses. This inhibition was IgG mediated and FcγRIIb dependent. Similarly, pre-OIT but not post-OIT sera from patients efficiently sensitized basophils for peanut-induced activation. IgG antibodies in post-OIT sera suppressed basophil activation by pre-OIT sera. This inhibition was blocked by antibodies against FcγRII. Food-specific IgG antibodies, such as those induced during OIT, inhibit IgE-mediated reactions. Strategies that favor IgG responses might prove useful in the management of food allergy.

Research paper thumbnail of Adenomatous Polyposis Coli Defines Treg Differentiation and Anti-inflammatory Function through Microtubule-Mediated NFAT Localization

Graphical Abstract Highlights d APC controls microtubule organization and NFAT-driven cytokine ge... more Graphical Abstract Highlights d APC controls microtubule organization and NFAT-driven cytokine gene expression d APC silencing impairs NFAT nuclear localization and activation d NFAT associates with microtubules that control its localization and its activation d Apc Min/+ Tregs have intrinsically reduced differentiation and IL-10 production

Research paper thumbnail of IgE receptor signaling in food allergy pathogenesis

Current Opinion in Immunology, 2015

The pathogenesis of food allergy remains poorly understood. Recent advances in the use of murine ... more The pathogenesis of food allergy remains poorly understood. Recent advances in the use of murine models have led to discoveries that mast cells and IgE receptor signaling not only drive immediate hypersensitivity reactions but also exert an immunoregulatory function, promoting the development of allergic sensitivity to foods. We review the evidence that IgE, IgE receptors, key signaling kinases and mast cells impair oral tolerance to ingested foods, preventing the induction of regulatory T cells (Treg) and promoting the acquisition of pro-allergic T helper (Th) 2 responses. We discuss innovative strategies that that could be implemented to counteract these immunoregulatory effects of IgE-mediated mast cell activation, and potentially reverse established sensitization, curing food allergy.

Research paper thumbnail of A microbiota signature associated with experimental food allergy promotes allergic sensitization and anaphylaxis

Journal of Allergy and Clinical Immunology, 2013

Background-Commensal microbiota play a critical role in maintaining oral tolerance. The effect of... more Background-Commensal microbiota play a critical role in maintaining oral tolerance. The effect of food allergy on the gut microbial ecology remains unknown. Objective-We sought to establish the composition of the gut microbiota in experimental food allergy and its role in disease pathogenesis. Methods-Food allergy-prone mice with a gain-of-function mutation in the IL-4 receptor α chain (Il4raF709) and wild-type (WT) control animals were subjected to oral sensitization with chicken egg ovalbumin (OVA). Enforced tolerance was achieved by using allergen-specific regulatory T (Treg) cells. Community structure analysis of gut microbiota was performed by using a high-density 16S rDNA oligonucleotide microarrays (PhyloChip) and massively parallel pyrosequencing of 16S rDNA amplicons. Results-OVA-sensitized Il4raF709 mice exhibited a specific microbiota signature characterized by coordinate changes in the abundance of taxa of several bacterial families,

Research paper thumbnail of A microbiota signature associated with experimental food allergy promotes allergic sensitization and anaphylaxis

Journal of Allergy and Clinical Immunology, 2013

Background-Commensal microbiota play a critical role in maintaining oral tolerance. The effect of... more Background-Commensal microbiota play a critical role in maintaining oral tolerance. The effect of food allergy on the gut microbial ecology remains unknown. Objective-We sought to establish the composition of the gut microbiota in experimental food allergy and its role in disease pathogenesis. Methods-Food allergy-prone mice with a gain-of-function mutation in the IL-4 receptor α chain (Il4raF709) and wild-type (WT) control animals were subjected to oral sensitization with chicken egg ovalbumin (OVA). Enforced tolerance was achieved by using allergen-specific regulatory T (Treg) cells. Community structure analysis of gut microbiota was performed by using a high-density 16S rDNA oligonucleotide microarrays (PhyloChip) and massively parallel pyrosequencing of 16S rDNA amplicons. Results-OVA-sensitized Il4raF709 mice exhibited a specific microbiota signature characterized by coordinate changes in the abundance of taxa of several bacterial families,

Research paper thumbnail of A booster dose enhances immunogenicity of the COVID-19 vaccine candidate ChAdOx1 nCoV-19 in aged mice

The spread of SARS-CoV-2 has caused a global pandemic that has affected almost every aspect of hu... more The spread of SARS-CoV-2 has caused a global pandemic that has affected almost every aspect of human life. The development of an effective COVID-19 vaccine could limit the morbidity and mortality caused by infection, and may enable the relaxation of social distancing measures. Age is one of the most significant risk factors for poor health outcomes after SARS-CoV-2 infection, therefore it is desirable that any new vaccine candidates should elicit a robust immune response in older adults. Here, we test the immunogenicity of the adenoviral vectored vaccine ChAdOx1 nCoV-19 (AZD-1222) in aged mice. We find that a single dose of this vaccine induces cellular and humoral immunity in aged mice, but at a reduced magnitude than in younger adult mice. Furthermore, we report that a second dose enhances the immune response to this vaccine in aged mice, indicating that a primeboost strategy may be a rational approach to enhance immunogenicity in older persons.

Research paper thumbnail of An open resource for T cell phenotype changes in COVID-19 identifies IL-10-producing regulatory T cells as characteristic of severe cases

The pandemic spread of the novel coronavirus SARS-CoV-2 is due, in part, to the immunological pro... more The pandemic spread of the novel coronavirus SARS-CoV-2 is due, in part, to the immunological properties of the host-viral interaction. The clinical presentation varies greatly from individual to individual, with asymptomatic carriers, mild to moderate-presenting patients and severely affected patients. Variation in immune response to SARS-CoV-2 may underlie this clinical variation. Using a high dimensional systems immunology platform we have analysed the peripheral blood compartment of 6 healthy individuals, 23 mild-to-moderate COVID-19 patients and 20 severe COVID-19 patients. We identify distinct immunological signatures in the peripheral blood of the mild-to-moderate and severe COVID-19 patients, including T cell lymphopenia, more consistent with peripheral hypo- than hyper-immune activation. Unique to the severe COVID-19 cases was a large increase in the proportion of IL-10-secreting regulatory T cells, a lineage known to possess anti-inflammatory properties in the lung. Annota...

Research paper thumbnail of Mice Deficient in Nucleoporin Nup210 Develop Peripheral T Cell Alterations

Research paper thumbnail of Stem-cell-derived human microglia transplanted in mouse brain to study human disease

Research paper thumbnail of Insufficient IL-10 Production as a Mechanism Underlying the Pathogenesis of Systemic Juvenile Idiopathic Arthritis

The Journal of Immunology

Research paper thumbnail of Mechanical Skin Injury Promotes Food Anaphylaxis by Driving Intestinal Mast Cell Expansion

Research paper thumbnail of Stem cell derived human microglia transplanted in mouse brain to study genetic risk of Alzheimer's Disease

Genetics highlight the central role of microglia in Alzheimer's disease but at least 36% of A... more Genetics highlight the central role of microglia in Alzheimer's disease but at least 36% of AD-risk genes lack good mouse orthologues. Here, we show that embryonic stem cell (ESC)-derived human microglia successfully engraft the mouse brain and recapitulate transcriptionally primary human microglia derived from human surgical samples. Upon exposure to oligomeric Aβ a wide range of AD-risk genes are expressed that are not readily studied in current mouse models for AD. This work provides a unique humanized animal model that will allow elucidating the role of genetic risk in the pathogenesis of AD.

Research paper thumbnail of NFIL3 mutations alter immune homeostasis and sensitise for arthritis pathology

Annals of the rheumatic diseases, Jan 14, 2018

is a key immunological transcription factor, with knockout mice studies identifying functional ro... more is a key immunological transcription factor, with knockout mice studies identifying functional roles in multiple immune cell types. Despite the importance of NFIL3, little is known about its function in humans. Here, we characterised a kindred of two monozygotic twin girls with juvenile idiopathic arthritis at the genetic and immunological level, using whole exome sequencing, single cell sequencing and flow cytometry. Parallel studies were performed in a mouse model. The patients inherited a novel p.M170I in NFIL3 from each of the parents. The mutant form of NFIL3 demonstrated reduced stability in vitro. The potential contribution of this mutation to arthritis susceptibility was demonstrated through a preclinical model, where Nfil3-deficient mice upregulated IL-1β production, with more severe arthritis symptoms on disease induction. Single cell sequencing of patient blood quantified the transcriptional dysfunctions present across the peripheral immune system, converging on IL-1β as ...

Research paper thumbnail of {"__content__"=>"The Long Non-coding RNA Anticipates Foxp3 Expression in Regulatory T Cells.", "i"=>{"__content__"=>"Flatr"}}

Frontiers in immunology, 2018

Mammalian genomes encode a plethora of long non-coding RNA (lncRNA). These transcripts are though... more Mammalian genomes encode a plethora of long non-coding RNA (lncRNA). These transcripts are thought to regulate gene expression, influencing biological processes from development to pathology. Results from the few lncRNA that have been studied in the context of the immune system have highlighted potentially critical functions as network regulators. Here we explored the nature of the lncRNA transcriptome in regulatory T cells (Tregs), a subset of CD4 T cells required to establish and maintain immunological self-tolerance. The identified Treg lncRNA transcriptome showed distinct differences from that of non-regulatory CD4 T cells, with evidence of direct shaping of the lncRNA transcriptome by Foxp3, the master transcription factor driving the distinct mRNA profile of Tregs. Treg lncRNA changes were disproportionally reversed in the absence of Foxp3, with an enrichment for colocalisation with Foxp3 DNA binding sites, indicating a direct coordination of transcription by Foxp3 independent...

Research paper thumbnail of Tissue-Specific Expression of the Low-Affinity IgG Receptor, FcγRIIb, on Human Mast Cells

Frontiers in immunology, 2018

Immediate hypersensitivity reactions are induced by the interaction of allergens with specific Ig... more Immediate hypersensitivity reactions are induced by the interaction of allergens with specific IgE antibodies bound FcεRI to mast cells and basophils. While these specific IgE antibodies are needed to trigger such reactions, not all individuals harboring IgE exhibit symptoms of allergy. The lack of responsiveness seen in some subjects correlates with the presence of IgG antibodies of the same specificity. In cell culture studies and animal models of food allergy and anaphylaxis such IgG antibodies have been shown to exert suppression FcγRIIb. However, the reported absence of this inhibitory receptor on primary mast cells derived from human skin has raised questions about the role of IgG-mediated inhibition of immediate hypersensitivity in human subjects. Here, we tested the hypothesis that mast cell FcγRIIb expression might be tissue specific. Utilizing a combination of flow cytometry, quantitative PCR, and immunofluorescence staining of mast cells derived from the tissues of humani...

Research paper thumbnail of Phenotype molding of stromal cells in the lung tumor microenvironment

Nature medicine, Jan 9, 2018

Cancer cells are embedded in the tumor microenvironment (TME), a complex ecosystem of stromal cel... more Cancer cells are embedded in the tumor microenvironment (TME), a complex ecosystem of stromal cells. Here, we present a 52,698-cell catalog of the TME transcriptome in human lung tumors at single-cell resolution, validated in independent samples where 40,250 additional cells were sequenced. By comparing with matching non-malignant lung samples, we reveal a highly complex TME that profoundly molds stromal cells. We identify 52 stromal cell subtypes, including novel subpopulations in cell types hitherto considered to be homogeneous, as well as transcription factors underlying their heterogeneity. For instance, we discover fibroblasts expressing different collagen sets, endothelial cells downregulating immune cell homing and genes coregulated with established immune checkpoint transcripts and correlating with T-cell activity. By assessing marker genes for these cell subtypes in bulk RNA-sequencing data from 1,572 patients, we illustrate how these correlate with survival, while immunohi...

Research paper thumbnail of IL-4 production by group 2 innate lymphoid cells promotes food allergy by blocking regulatory T-cell function

Journal of Allergy and Clinical Immunology, 2016

Food allergy is a major health issue, but its pathogenesis remains obscure. Group 2 innate lympho... more Food allergy is a major health issue, but its pathogenesis remains obscure. Group 2 innate lymphoid cells (ILC2s) promote allergic inflammation. However their role in food allergy is largely unknown. We sought to investigate the role of ILC2s in food allergy. Food allergy-prone mice with a gain-of-function mutation in the IL-4 receptor α chain (Il4raF709) were orally sensitized with food allergens, and the ILC2 compartment was analyzed. The requirement for ILC2s in food allergy was investigated by using Il4raF709, IL-33 receptor-deficient (Il1rl1(-/-)), IL-13-deficient (Il13(-/-)), and IL-4-deficient (Il4(-/-)) mice and by adoptive transfer of in vitro-expanded ILC2s. Direct effects of ILC2s on regulatory T (Treg) cells and mast cells were analyzed in coculture experiments. Treg cell control of ILC2s was assessed in vitro and in vivo. Il4raF709 mice with food allergy exhibit increased numbers of ILC2s. IL-4 secretion by ILC2s contributes to the allergic response by reducing allergen-specific Treg cell and activating mast cell counts. IL-33 receptor deficiency in Il4raF709 Il1rl1(-/-) mice protects against allergen sensitization and anaphylaxis while reducing ILC2 induction. Adoptive transfer of wild-type and Il13(-/-) but not Il4(-/-) ILC2s restored sensitization in Il4raF709 Il1rl1(-/-) mice. Treg cells suppress ILC2s in vitro and in vivo. IL-4 production by IL-33-stimulated ILC2s blocks the generation of allergen-specific Treg cells and favors food allergy. Strategies to block ILC2 activation or the IL-33/IL-33 receptor pathway can lead to innovative therapies in the treatment of food allergy.

Research paper thumbnail of A humanized mouse model of anaphylactic peanut allergy

Journal of Allergy and Clinical Immunology, 2016

Food allergy is a growing health problem with very limited treatment options. Investigation of th... more Food allergy is a growing health problem with very limited treatment options. Investigation of the immunologic pathways underlying allergic sensitization to foods in humans has been greatly constrained by the limited availability of intestinal tissue and gut-resident immune cells. Although mouse models have offered insights into pathways of food sensitization, differences between rodent and human immune physiology limit the extension of these findings to our understanding of human disease. We sought to develop a strategy for the generation of mice with humanized adaptive immune systems, complete with tissue engraftment by human mast cells that are competent to mount specific IgE-mediated responses and drive systemic anaphylaxis on ingestion challenge. Nonobese diabetic severe combined immunodeficient mice lacking the cytokine receptor common gamma chain (γc(-/-)) and carrying a human stem cell factor transgene were engrafted with human hematopoietic stem cells. The impact of peanut (PN) feeding and IgE neutralization on the development of immune responses, mast cell homeostasis, and anaphylactic food allergy was assessed in these animals. Humanized nonobese diabetic severe combined immunodeficient common gamma chain-deficient stem cell factor (huNSG) mice exhibited robust engraftment with functional human T and B lymphocytes and human mast cells were found in significant numbers in their tissues, including the intestinal mucosa. Following gavage feeding with PN, they mounted specific antibody responses, including PN-specific IgE. When enterally challenged with PN, they exhibited mast-cell-mediated systemic anaphylaxis, as indicated by hypothermia and increases in plasma tryptase levels. Anti-IgE (omalizumab) treatment ablated this anaphylactic response. huNSG mice provide a novel tool for studying food allergy and IgE-mediated anaphylaxis.

Research paper thumbnail of Oral immunotherapy induces IgG antibodies that act through Fc?RIIb to suppress IgE-mediated hypersensitivity

Data Revues 00916749 Unassign S0091674914008033, Jul 18, 2014

Food-induced anaphylaxis is triggered by specific IgE antibodies. Paradoxically, some subjects wi... more Food-induced anaphylaxis is triggered by specific IgE antibodies. Paradoxically, some subjects with significant IgE levels can ingest allergenic foods without incident. Similarly, subjects completing oral immunotherapy (OIT) tolerate food challenges despite persistent high-titer food-specific IgE. We sought to test whether IgG antibodies induced by food immunotherapy prevent food-induced anaphylaxis and whether this occurs through the inhibitory receptor FcγRIIb. Food allergy-susceptible Il4raF709 mice were enterally sensitized to ovalbumin (OVA). Similarly sensitized IgE-deficient (IgE(-/-)) Il4raF709 mice, which can ingest OVA without anaphylaxis, were subjected to a high-dose enteral OVA desensitization protocol (OIT). Sera from both groups were tested for the ability to activate or inhibit bone marrow mast cells (BMMCs) exposed to allergen or to passively transfer allergy to naive hosts. In parallel experiments sera obtained from patients with peanut allergy before and after undergoing OIT were interrogated for their ability to enhance or suppress peanut-induced activation in an indirect assay by using basophils from nonallergic donors. Il4raF709 mice exhibited strong OVA-specific IgE responses. Their sera efficiently sensitized BMMCs for activation by antigen challenge. Sera from Il4raF709/IgE(-/-) mice subjected to OVA OIT suppressed BMMC responses. This inhibition was IgG mediated and FcγRIIb dependent. Similarly, pre-OIT but not post-OIT sera from patients efficiently sensitized basophils for peanut-induced activation. IgG antibodies in post-OIT sera suppressed basophil activation by pre-OIT sera. This inhibition was blocked by antibodies against FcγRII. Food-specific IgG antibodies, such as those induced during OIT, inhibit IgE-mediated reactions. Strategies that favor IgG responses might prove useful in the management of food allergy.

Research paper thumbnail of Parasite modulation of autoimmune diseases

Research paper thumbnail of Oral immunotherapy induces IgG antibodies that act through Fc?RIIb to suppress IgE-mediated hypersensitivity

Data Revues 00916749 Unassign S0091674914008033, Jul 18, 2014

Food-induced anaphylaxis is triggered by specific IgE antibodies. Paradoxically, some subjects wi... more Food-induced anaphylaxis is triggered by specific IgE antibodies. Paradoxically, some subjects with significant IgE levels can ingest allergenic foods without incident. Similarly, subjects completing oral immunotherapy (OIT) tolerate food challenges despite persistent high-titer food-specific IgE. We sought to test whether IgG antibodies induced by food immunotherapy prevent food-induced anaphylaxis and whether this occurs through the inhibitory receptor FcγRIIb. Food allergy-susceptible Il4raF709 mice were enterally sensitized to ovalbumin (OVA). Similarly sensitized IgE-deficient (IgE(-/-)) Il4raF709 mice, which can ingest OVA without anaphylaxis, were subjected to a high-dose enteral OVA desensitization protocol (OIT). Sera from both groups were tested for the ability to activate or inhibit bone marrow mast cells (BMMCs) exposed to allergen or to passively transfer allergy to naive hosts. In parallel experiments sera obtained from patients with peanut allergy before and after undergoing OIT were interrogated for their ability to enhance or suppress peanut-induced activation in an indirect assay by using basophils from nonallergic donors. Il4raF709 mice exhibited strong OVA-specific IgE responses. Their sera efficiently sensitized BMMCs for activation by antigen challenge. Sera from Il4raF709/IgE(-/-) mice subjected to OVA OIT suppressed BMMC responses. This inhibition was IgG mediated and FcγRIIb dependent. Similarly, pre-OIT but not post-OIT sera from patients efficiently sensitized basophils for peanut-induced activation. IgG antibodies in post-OIT sera suppressed basophil activation by pre-OIT sera. This inhibition was blocked by antibodies against FcγRII. Food-specific IgG antibodies, such as those induced during OIT, inhibit IgE-mediated reactions. Strategies that favor IgG responses might prove useful in the management of food allergy.

Research paper thumbnail of Adenomatous Polyposis Coli Defines Treg Differentiation and Anti-inflammatory Function through Microtubule-Mediated NFAT Localization

Graphical Abstract Highlights d APC controls microtubule organization and NFAT-driven cytokine ge... more Graphical Abstract Highlights d APC controls microtubule organization and NFAT-driven cytokine gene expression d APC silencing impairs NFAT nuclear localization and activation d NFAT associates with microtubules that control its localization and its activation d Apc Min/+ Tregs have intrinsically reduced differentiation and IL-10 production

Research paper thumbnail of IgE receptor signaling in food allergy pathogenesis

Current Opinion in Immunology, 2015

The pathogenesis of food allergy remains poorly understood. Recent advances in the use of murine ... more The pathogenesis of food allergy remains poorly understood. Recent advances in the use of murine models have led to discoveries that mast cells and IgE receptor signaling not only drive immediate hypersensitivity reactions but also exert an immunoregulatory function, promoting the development of allergic sensitivity to foods. We review the evidence that IgE, IgE receptors, key signaling kinases and mast cells impair oral tolerance to ingested foods, preventing the induction of regulatory T cells (Treg) and promoting the acquisition of pro-allergic T helper (Th) 2 responses. We discuss innovative strategies that that could be implemented to counteract these immunoregulatory effects of IgE-mediated mast cell activation, and potentially reverse established sensitization, curing food allergy.