ABSTRACT: Encounters between host cells and intracellular bacterial pathogens lead to complex phenotypes that determine the outcome of infection. Single-cell RNA-sequencing (scRNA-seq) are increasingly used to study the host factors underlying diverse cellular phenotypes. But current approaches do not permit the simultaneous unbiased study of both host and bacterial factors during infection. Here, we developed scPAIR-seq, an approach to analyze both host and pathogen factors during infection by combining multiplex-tagged mutant bacterial library with scRNA-seq to identify mutant-specific changes in host transcriptomes. We applied scPAIR-seq to macrophages infected with a library of Salmonella Typhimurium secretion system effector mutants. We developed a pipeline to independently analyze redundancy between effectors and mutant-specific unique fingerprints, and mapped the global virulence network of each individual effector by its impact on host immune pathways. ScPAIR-seq is a powerful tool to untangle bacterial virulence strategies and their complex interplay with host defense strategies that drive infection outcome.
Project description:Encounters between host cells and intracellular bacterial pathogens lead to complex phenotypes that determine the outcome of infection. Single-cell RNA-sequencing (scRNA-seq) are increasingly used to study the host factors underlying diverse cellular phenotypes. But current approaches do not permit the simultaneous unbiased study of both host and bacterial factors during infection. Here, we developed scPAIR-seq, an approach to analyze both host and pathogen factors during infection by combining multiplex-tagged mutant bacterial library with scRNA-seq to identify mutant-specific changes in host transcriptomes. We applied scPAIR-seq to macrophages infected with a library of Salmonella Typhimurium secretion system effector mutants. We developed a pipeline to independently analyze redundancy between effectors and mutant-specific unique fingerprints, and mapped the global virulence network of each individual effector by its impact on host immune pathways. ScPAIR-seq is a powerful tool to untangle bacterial virulence strategies and their complex interplay with host defense strategies that drive infection outcome.
Project description:Encounters between host cells and intracellular bacterial pathogens lead to complex phenotypes that determine the outcome of infection. Single-cell RNA-sequencing (scRNA-seq) are increasingly used to study the host factors underlying diverse cellular phenotypes. But current approaches do not permit the simultaneous unbiased study of both host and bacterial factors during infection. Here, we developed scPAIR-seq, an approach to analyze both host and pathogen factors during infection by combining multiplex-tagged mutant bacterial library with scRNA-seq to identify mutant-specific changes in host transcriptomes. We applied scPAIR-seq to macrophages infected with a library of Salmonella Typhimurium secretion system effector mutants. We developed a pipeline to independently analyze redundancy between effectors and mutant-specific unique fingerprints, and mapped the global virulence network of each individual effector by its impact on host immune pathways. ScPAIR-seq is a powerful tool to untangle bacterial virulence strategies and their complex interplay with host defense strategies that drive infection outcome.
Project description:Encounters between host cells and intracellular bacterial pathogens lead to complex phenotypes that determine the outcome of infection. Single-cell RNA-sequencing (scRNA-seq) are increasingly used to study the host factors underlying diverse cellular phenotypes. But current approaches do not permit the simultaneous unbiased study of both host and bacterial factors during infection. Here, we developed scPAIR-seq, an approach to analyze both host and pathogen factors during infection by combining multiplex-tagged mutant bacterial library with scRNA-seq to identify mutant-specific changes in host transcriptomes. We applied scPAIR-seq to macrophages infected with a library of Salmonella Typhimurium secretion system effector mutants. We developed a pipeline to independently analyze redundancy between effectors and mutant-specific unique fingerprints, and mapped the global virulence network of each individual effector by its impact on host immune pathways. ScPAIR-seq is a powerful tool to untangle bacterial virulence strategies and their complex interplay with host defense strategies that drive infection outcome.
Project description:Encounters between host cells and intracellular bacterial pathogens lead to complex phenotypes that determine the outcome of infection. Single-cell RNA-sequencing (scRNA-seq) are increasingly used to study the host factors underlying diverse cellular phenotypes. But current approaches do not permit the simultaneous unbiased study of both host and bacterial factors during infection. Here, we developed scPAIR-seq, an approach to analyze both host and pathogen factors during infection by combining multiplex-tagged mutant bacterial library with scRNA-seq to identify mutant-specific changes in host transcriptomes. We applied scPAIR-seq to macrophages infected with a library of Salmonella Typhimurium secretion system effector mutants. We developed a pipeline to independently analyze redundancy between effectors and mutant-specific unique fingerprints, and mapped the global virulence network of each individual effector by its impact on host immune pathways. ScPAIR-seq is a powerful tool to untangle bacterial virulence strategies and their complex interplay with host defense strategies that drive infection outcome.
Project description:Encounters between host cells and intracellular bacterial pathogens lead to complex phenotypes that determine the outcome of infection. Single-cell RNA-sequencing (scRNA-seq) are increasingly used to study the host factors underlying diverse cellular phenotypes. But current approaches do not permit the simultaneous unbiased study of both host and bacterial factors during infection. Here, we developed scPAIR-seq, an approach to analyze both host and pathogen factors during infection by combining multiplex-tagged mutant bacterial library with scRNA-seq to identify mutant-specific changes in host transcriptomes. We applied scPAIR-seq to macrophages infected with a library of Salmonella Typhimurium secretion system effector mutants. We developed a pipeline to independently analyze redundancy between effectors and mutant-specific unique fingerprints, and mapped the global virulence network of each individual effector by its impact on host immune pathways. ScPAIR-seq is a powerful tool to untangle bacterial virulence strategies and their complex interplay with host defense strategies that drive infection outcome.
Project description:Encounters between host cells and intracellular bacterial pathogens lead to complex phenotypes that determine the outcome of infection. Single-cell RNA-sequencing (scRNA-seq) are increasingly used to study the host factors underlying diverse cellular phenotypes. But current approaches do not permit the simultaneous unbiased study of both host and bacterial factors during infection. Here, we developed scPAIR-seq, an approach to analyze both host and pathogen factors during infection by combining multiplex-tagged mutant bacterial library with scRNA-seq to identify mutant-specific changes in host transcriptomes. We applied scPAIR-seq to macrophages infected with a library of Salmonella Typhimurium secretion system effector mutants. We developed a pipeline to independently analyze redundancy between effectors and mutant-specific unique fingerprints, and mapped the global virulence network of each individual effector by its impact on host immune pathways. ScPAIR-seq is a powerful tool to untangle bacterial virulence strategies and their complex interplay with host defense strategies that drive infection outcome.
Project description:The factors that determine the outcome of clinical tuberculosis lie within both the host and the pathogen, Mycobacterium tuberculosis (Mtb). The advent of recombinant inbred mouse panels and next-generation transposon mutagenesis and sequencing approaches has enabled dissection of the host-pathogen interface for mammalian and pathogen genetic determinants of disease outcome. To identify host and pathogen genetic drivers of Mtb infection, we infected 19 genotypes from the BXD panel, bred from Mtb-resistant C57BL/6J (B6) and Mtb-susceptible DBA/2J (D2), with a comprehensive library of transposon mutants (TnSeq). The survival of each of the ~4000 bacterial mutants within each distinct host was quantified and leveraged as refined “endophenotypes”, directly reporting on the infection microenvironment. We leveraged QTL mapping to associate each varying bacterial fitness endophenotype to the host genome and identified 140 significant host-pathogen quantitative trait loci (hpQTL). This host-pathogen interaction screen reinforces the utility of bacterial mutant libraries as precise reporters of host immunological microenvironment during infection and highlights host gene candidates for further investigation.
Project description:Interactions between intracellular bacteria and mononuclear phagocytes give rise to diverse cellular phenotypes that may determine the outcome of infection. Recent advances in single-cell RNA-seq (scRNA-seq) have identified multiple subsets within the mononuclear population, but implications to their function during infection remain unknown. Here, we applied microscopy, flow cytometry and scRNA-seq to survey the mononuclear niche of intracellular Salmonella Typhimurium (S.Tm) during early systemic infection in mice. We describe eclipse-like growth kinetics in the spleen, with a first phase of bacterial control mediated by tissue-resident red-pulp macrophages. A second phase involved extensive bacterial replication within a newly identified macrophage population characterized by CD9 expression. Using Nr4a1e2-/- mice we established that CD9+ macrophages originated from non-classical monocytes (NCM), and NCM-depleted mice were more resistant to S.Tm infection. Our study defines a novel host-pathogen interface, with macrophage subset-specific interactions that determines early infection dynamics and the infection outcome of the entire organism.
Project description:Interactions between intracellular bacteria and mononuclear phagocytes give rise to diverse cellular phenotypes that may determine the outcome of infection. Recent advances in single-cell RNA-seq (scRNA-seq) have identified multiple subsets within the mononuclear population, but implications to their function during infection remain unknown. Here, we applied microscopy, flow cytometry and scRNA-seq to survey the mononuclear niche of intracellular Salmonella Typhimurium (S.Tm) during early systemic infection in mice. We describe eclipse-like growth kinetics in the spleen, with a first phase of bacterial control mediated by tissue-resident red-pulp macrophages. A second phase involved extensive bacterial replication within a newly identified macrophage population characterized by CD9 expression. Using Nr4a1e2-/- mice we established that CD9+ macrophages originated from non-classical monocytes (NCM), and NCM-depleted mice were more resistant to S.Tm infection. Our study defines a novel host-pathogen interface, with macrophage subset-specific interactions that determines early infection dynamics and the infection outcome of the entire organism.
Project description:Interactions between intracellular bacteria and mononuclear phagocytes give rise to diverse cellular phenotypes that may determine the outcome of infection. Recent advances in single-cell RNA-seq (scRNA-seq) have identified multiple subsets within the mononuclear population, but implications to their function during infection remain unknown. Here, we applied microscopy, flow cytometry and scRNA-seq to survey the mononuclear niche of intracellular Salmonella Typhimurium (S.Tm) during early systemic infection in mice. We describe eclipse-like growth kinetics in the spleen, with a first phase of bacterial control mediated by tissue-resident red-pulp macrophages. A second phase involved extensive bacterial replication within a newly identified macrophage population characterized by CD9 expression. Using Nr4a1e2-/- mice we established that CD9+ macrophages originated from non-classical monocytes (NCM), and NCM-depleted mice were more resistant to S.Tm infection. Our study defines a novel host-pathogen interface, with macrophage subset-specific interactions that determines early infection dynamics and the infection outcome of the entire organism.