SITVITBovis-a publicly available database and mapping tool to get an improved overview of animal and human cases caused by Mycobacterium bovis

Limited data are available for bovine tuberculosis and the infections it can cause in humans and other mammals. We therefore constructed a publicly accessible SITVITBovis database that incorporates genotyping and epidemiological data on Mycobacterium bovis. It also includes limited data on Mycobacterium caprae (previously synonymous with the name M. bovis subsp. Caprae) that can infect both animals and humans. SITVITBovis incorporates data on 25,741 isolates corresponding to 60 countries of origin (75 countries of isolation). It reports a total of 1000 spoligotype patterns: 537 spoligotype international types (SITs, containing 25 278 clinical isolates) and 463 orphan patterns, allowing a wide overview of the geographic distribution of various phylogenetical sublineages (BOV_1, BOV_2, BOV_3 and BOV_4-CAPRAE). The SIT identifiers of the SITVITBovis were compared to the SB numbers of the Mbovis.org database to facilitate crosscheck among databases. Note that SITVITBovis also contains limited information on mycobacterial interspersed repetitive units-variable number of tandem repeats when available. Significant differences were observed when comparing age/gender of human isolates as well as various hosts. The database includes information on the regions where a strain was isolated as well as hosts involved, making it possible to see geographic trends. SITVITBovis is publicly accessible at: http://www.pasteur-guadeloupe.fr:8081/SITVIT_Bovis. Finally, a future second version is currently in progress to allow query of associated whole-genome sequencing data

FB5P-seq: FACS-Based 5-Prime End Single-Cell RNA-seq for Integrative Analysis of Transcriptome and Antigen Receptor Repertoire in B and T Cells

International audienceSingle-cell RNA sequencing (scRNA-seq) allows the identification, characterization, and quantification of cell types in a tissue. When focused on B and T cells of the adaptive immune system, scRNA-seq carries the potential to track the clonal lineage of each analyzed cell through the unique rearranged sequence of its antigen receptor (BCR or TCR, respectively) and link it to the functional state inferred from transcriptome analysis. Here we introduce FB5P-seq, a FACS-based 5′-end scRNA-seq method for cost-effective, integrative analysis of transcriptome and paired BCR or TCR repertoire in phenotypically defined B and T cell subsets. We describe in detail the experimental workflow and provide a robust bioinformatics pipeline for computing gene count matricesand reconstructing repertoire sequences from FB5P-seq data. We further present two applications of FB5P-seq for the analysis of human tonsil B cell subsets and peripheral blood antigen-specific CD4T cells. We believe th at our novel integrative scRNA-seq method will be a valuable option to study rare adap tive immune cell subsets in immunology research

High-Dimensional Single-Cell Analysis Identifies Organ-Specific Signatures and Conserved NK Cell Subsets in Humans and Mice.

Natural killer (NK) cells are innate lymphoid cells (ILCs) involved in antimicrobial and antitumoral responses. Several NK cell subsets have been reported in humans and mice, but their heterogeneity across organs and species remains poorly characterized. We assessed the diversity of human and mouse NK cells by single-cell RNA sequencing on thousands of individual cells isolated from spleen and blood. Unbiased transcriptional clustering revealed two distinct signatures differentiating between splenic and blood NK cells. This analysis at single-cell resolution identified three subpopulations in mouse spleen and four in human spleen, and two subsets each in mouse and human blood. A comparison of transcriptomic profiles within and between species highlighted the similarity of the two major subsets, NK1 and NK2, across organs and species. This unbiased approach provides insight into the biology of NK cells and establishes a rationale for the translation of mouse studies to human physiology and disease

The activation trajectory of plasmacytoid dendritic cells in vivo during a viral infection

International audienc

The activation trajectory of plasmacytoid dendritic cells in vivo during a viral infection

International audiencePlasmacytoid dendritic cells (pDCs) are a major source of type I interferon (IFN-I). What other functions pDCs exert in vivo during viral infections is controversial, and more studies are needed to understand their orchestration. In the present study, we characterize in depth and link pDC activation states in animals infected by mouse cytomegalovirus by combining Ifnb1 reporter mice with flow cytometry, single-cell RNA sequencing, confocal microscopy and a cognate CD4 T cell activation assay. We show that IFN-I production and T cell activation were performed by the same pDC, but these occurred sequentially in time and in different micro-anatomical locations. In addition, we show that pDC commitment to IFN-I production was marked early on by their downregulation of leukemia inhibitory factor receptor and was promoted by cell-intrinsic tumor necrosis factor signaling. We propose a new model for how individual pDCs are endowed to exert different functions in vivo during a viral infection, in a manner tightly orchestrated in time and space