Project description:In response to antigen challenge, human B cells clonally expand, undergo selection and differentiate within secondary lymphoid tissues to produce mature B cell subsets and high affinity antibodies necessary for an effective immune response. However, the interplay between affinity, antibody class and different B cell fates has proved challenging to decipher in primary human tissue. We have applied an integrated analysis of bulk and single-cell antibody repertoires paired with single-cell transcriptomics of human B cells from a model secondary lymphoid tissue. Specifically, here we have performed bulk B cell repertoire sequencing of the immunoglobulin heavy chain (IgH) for sorted B cell subsets from paediatric tonsil tissue. Matched single-cell gene expression and single-cell VDJ data are also available for the same patient donors.
Project description:We sought to investigate the extent of genetic and antigen-driven predetermination of antibody repertoires throughout B-cell development (pre-B cells, naive B cells, plasma cells). To this end, we used (i) an inbred model organism (mouse, C57BL/6J) to quantify genetic predetermination and (ii) cohort-stratification (4 cohorts: 1 untreated, 3 antigen-immunized) to quantify antigen-driven predetermination. To ensure generalizability of our research, we additionally sequenced naive B cells from Balb/c and pet shop mice.
Project description:Antibody repertoire sequencing of blood and bone marrow plasma cell compartments following lymphocytic choriomeningitis virus infection. Heavy chain repertoires of 5 uninfected mice, 5 acutely infected mice and 5 chronically infected mice were longitudinally sequenced over 80 days. All samples are named according to the following scheme: dpi#_cohort$_R&.fastq.gz . dpi = days post infection = for all samples following the start of infection. Those samples starting with dm10 correspond to blood samples taken before the introduction of any virus. # = time point post virus infection cohort=acute (LCMV), chronic (LCMV), or naive (uninfected) animals $= mouse number, 1-5 R&=paired read, either R1 or R2 Those samples with \"bmpc\" in title correspond to sorted plasma cells (CD138hi, CD19lo) from bone marrow Example: dpi70_chronic3_R2.fastq.gz == blood repertoire 70 days post chronic LCMV infection in chronically-infected mouse#3
Project description:<p>We developed an improved high throughput sequencing approach to measure the quantities and sequences of the repertoire of antibody heavy chain RNA in a blood sample. Using this approach we analyzed the antibody repertoire in response to yearly vaccinations with influenza vaccines TIV and LAIV in healthy adults in two subsequent years. We determined vaccine response patterns specific to LAIV and TIV and found antibody sequences that were shared between two samples of the same individuals following influenza vaccination in subsequent years, thereby providing a genetic measurement of B-cell memory recall.</p>
Project description:<p>We developed an improved high throughput sequencing approach to measure the quantities and sequences of the repertoire of antibody heavy chain RNA in a blood sample. Using this approach we analyzed the antibody repertoire in response to yearly vaccinations with influenza vaccines TIV and LAIV in healthy adults in two subsequent years. We determined vaccine response patterns specific to LAIV and TIV and found antibody sequences that were shared between two samples of the same individuals following influenza vaccination in subsequent years, thereby providing a genetic measurement of B-cell memory recall.</p>
| phs000656.v1.p1 | EGA
Project description:Characterization of heavy-chain antibody gene repertoires in Bactrian camels
Project description:Throughout life, humans experience repeated exposure to viral antigens through infection and vaccination, resulting in the generation of diverse, and largely unique, antigen specific antibody repertoires. A paramount feature of antibodies that enables their critical contributions in counteracting recurrent and novel pathogens, and consequently fostering their utility as valuable targets for therapeutic and vaccine development, is the exquisite specificity displayed against their target antigens. Yet, there is still limited understanding of the determinants of antibody-antigen specificity, particularly as a function of antibody sequence. In recent years, experimental characterization of antibody repertoires has led to novel insights into fundamental properties of antibody sequences, but has been largely decoupled from at-scale antigen specificity analysis. Here, using the LIBRA-seq technology, we generated a large dataset mapping antibody sequence to antigen specificity for thousands of B cells, by screening the repertoires of a set of healthy individuals against twenty viral antigens representing diverse pathogens of biomedical significance. Analysis uncovered virus specific patterns in variable gene usage, gene pairing, somatic hypermutation, as well as the presence of convergent antiviral signatures across multiple individuals, including the presence of public antibody clonotypes. Notably, our results showed that, for B cell receptors originating from different individuals but leveraging an identical combination of heavy and light chain variable genes, there is a specific CDRH3/CDRL3 identity threshold that defines whether these B cells may share the same antigen specificity. This finding provides a quantifiable measure of the relationship between antibody sequence and antigen specificity and further defines experimentally grounded criteria for defining public antibody clonality. Understanding the fundamental rules of antibody-antigen interactions can lead to transformative new approaches for the development of antibody therapeutics and vaccines against current and emerging viruses.
Project description:The immunoglobulin heavy-chain (Igh) locus undergoes large-scale contraction in pro-B cells, which facilitates VH-DJH recombination by juxtaposing distal VH genes next to the DJH- rearranged gene segment in the proximal Igh domain. By high-resolution mapping of long-range interactions, we now demonstrate that an array of local interaction domains establishes the three- dimensional structure of the extended Igh locus in lymphoid progenitors and thymocytes. In pro- B cells, these local domains engage in long-range interactions across the entire Igh locus, which depend on the transcription factors Pax5, YY1 and CTCF. The large VH gene cluster thereby undergoes flexible long-range interactions with the more rigidly structured 3M-bM-^@M-^Y proximal domain, which ensures that all VH genes can participate with similar probability in VH-DJH recombination to generate a diverse antibody repertoire. Notably, these long-range interactions appear to be an intrinsic feature of the VH gene cluster, as they are still generated upon mutation of the EM-NM-< enhancer, IGCR1 insulator or 3M-bM-^@M-^Y regulatory region present in the 3M-bM-^@M-^Y proximal Igh domain. 4C sequencing from mutliple celltypes with multiple viewpoints; uneven number of replicates ChIP-Seq