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Plasmablasts and germinal center founder cells developing in vivo

ABSTRACT: A range of cellular interactions and cytokines influence immunoglobulin class switch recombination (CSR), which occurs both in extrafollicular antibody responses and germinal centers. This study addresses where CSR occurs during extrafollicular responses, allowing identification of the cellular interactions and cytokine-producing cells that influence CSR in vivo. The response in mice of B cells specific for 4-hydroxy-3-nitrophenyl-acetyl (NP) to NP-Ficoll was analyzed. Immunohistology and flow cytometry confirm responding NP-binding cells move to the outer T zone of the spleen and start dividing there on the second day. During the third day they move either to follicles as germinal center founding cells, or extrafollicular foci as plasmablasts. Analysis of expression of AID, Bcl-6 and Blimp-1 mRNA in single NP-binding cells indicates a proportion of T zone B blasts express AID transiently without Bcl-6 and these cells are shown to undergo CSR. By contrast Blimp-1+ cells emerging on the third day and were universally AID- and hence unable to initiate CSR. Bcl-6 mRNA without protein, expressed by 40% of naïve NP-binding cells, is rapidly downregulated. Bcl-6 and AID are coexpressed by germinal centre founding cells only on moving to follicles during the third day after immunization. Keywords: TaqMan Low Density Array

ORGANISM(S): Mus musculus

PROVIDER: GSE7744 | GEO | 2008/01/01

SECONDARY ACCESSION(S): PRJNA99857

REPOSITORIES: GEO

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Bach2 regulates AID-mediated immunoglobulin gene conversion and somatic hypermutation in DT40 B cells

Project description:The transcription factor Bach2 is required for germinal center formation and somatic hypermutation (SHM) of immunoglobulins, both central to an efficient antibody-mediated immune response. Activation-induced cytidine deaminase (AID) initiates SHM and CSR in germinal centers and has potential to induce human B cell lymphoma. To understand the role of Bach2 in AID-mediated immunoglobulin gene diversification processes, we established a Bach2-deficient DT40 B cell line. We show that in addition to allowing SHM, Bach2 drives immunoglobulin gene conversion (GCV), an important AID-dependent antibody gene diversification process. We demonstrate that Bach2 promotes GCV by increasing the expression of AID. Importantly, we found that the regulation of AID is independent of Blimp-1 and that Bach2-deficient cells have altered expression of several genes regulating AID expression, stability and function. These results demonstrate that Bach2 has a previously unappreciated role in the production of high-affinity antibodies.

2017-03-27 | GSE92430 | GEO

SFR KO mice germinal center B cell RNA sequencing

Project description:WT-AID-GFP+ and SFR KO-AID-GFP+ mice were immunized with NP(18)OVA+ alum, on Day 9, germinal center B cells (AID-GFP+) were sorted for total RNA

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Transcription factor Ascl2 promotes geminal center B cell responses through directly regulating AID transcription

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2021-03-30 | GSE169416 | GEO

Extrafollicular IgD+ B cells Generate IgE Antibody Secreting Cells in the Nasal Mucosa

Project description:Here we describe the dynamics underlying the generation of IgE-antibody secreting cells (ASC) in human nasal polyps (NP), mucosal tissues rich in ASC without germinal centers (GC). Using VH next generation sequencing, we identified an extrafollicular (EF) mucosal IgD+ naïve-like intermediate B cell population with high connectivity to the mucosal IgE ASC. Mucosal IgD+ B cells, express germline epsilon transcripts and predominantly co-express IgM. However, a small but significant fraction co-express IgG or IgA instead which also show connectivity to ASC IgE. Phenotypically, NP IgD+ B cells display an activated profile and molecular evidence of BCR engagement. Transcriptionally, mucosal IgD+ B cells reveal an intermediate profile between naïve B cells and ASC. Single cell IgE ASC analysis demonstrates lower mutational frequencies relative to IgG, IgA, and IgD ASC consistent with IgE ASC derivation from mucosal IgD+ B cell with low mutational load. In conclusion, we describe a novel mechanism of GC-independent, extrafollicular IgE ASC formation at the nasal mucosa whereby activated IgD+ naïve B cells locally undergo direct and indirect (through IgG and IgA), IgE class-switch.

2021-05-13 | GSE174349 | GEO

Gene expression analysis of B-NHL from λMYC, λMYC/IµHABCL6, λMYC/AIDKO and λMYC/IµHABCL6/AIDKO mouse models

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Gene expression comparison, WT and PDAP1-deficient primary B lymphocytes

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2020-06-19 | GSE141876 | GEO

RNAseq of germinal center B cells from Blimp-1-GFP reporter mice

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2018-12-20 | GSE111416 | GEO

The histone chaperone Spt6 is required for AID target determination through H3K4me3 regulation

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2013-02-01 | E-GEOD-35334 | biostudies-arrayexpress

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