Project description:The production of IL-21 by T follicular helper (Tfh) cells is vital in driving the germinal centre reaction and high affinity antibody formation. However, the degree of Tfh cell heterogeneity and function is not fully understood. Using a novel IL-21eGFP reporter mouse strain, we identified a subpopulation of GFP+ highly differentiated Tfh cells in Peyer’s Patches. In vitro, GFP+ cells that did not co-express IL-17 or Foxp3 were induced by CD3 and CD28 stimulation of naïve CD4+ cells from IL-21eGFP mice in cultures containing IL-6, TGFβ and retinoic acid. In vivo, the differentiation of GFP+Tfh cells in Peyer’s Patches was induced by intestinal bacteria, and required CD4+ T cells and B cells with diverse repertoires. Analysis of the TCRβ repertoire of Peyer’s Patches CD4+ T cell subpopulations demonstrated that GFP+Tfh cells are polyclonal and closely related to GFP-Tfh cells. Importantly, ablation of GFP+ cells resulted in a reduced frequency of Peyer’s Patches germinal center B cells and small but significant shifts in gut microbiome composition. Thus, using a new IL-21-reporter mouse we have identified a subpopulation of Tfh cells induced by the gut microbiota and necessary for optimal Peyer’s Patches germinal center responses.
Project description:147 B-cell lymphomas were studies for miRNA expression miRNA profiling of control human B cell populations Comparison of miRNA expression profiles of naive B cells (CD19+ IgD+ CD27-) from 3 individuals and germinal center B cells (CD10+ CD19+) from 4 individuals 147 B-cell lymphomas were hybridized on a human miRNA one-color platform containing probes for 470 human miRNAs. Each lymphoma type was compared to all set of NHLs. Burkitt Lymphoma was also directly compared to DLBCL miRNA expression signature is different in human naive B cells compared to Germinal Center B cells
Project description:We report the high-throughput profiling of murine naive B cells, germinal center (dark zone and light zone) B cells, and plasma cells transcriptome. By obtaining over 5 million bases of sequence, we generated genome-wide expression maps of cell subsets from WT mice and aPIK3CD mice. We find that activated PIK3CD signaling lead to significant alteration in gene expression of plasma cells.
Project description:In order to assess the miRNA signature of B cells undergoing the germinal center reaction, we isolated three subsets of B cells from tonsils--naive (N), germinal center (GC), and memory (M) and looked at their miRNA profile.
Project description:miRNA profiling has been performed on normal mature B cells at different stages of differentiation (naive, germinal center and memory). The main goal is to identify miRNA signatures associated with differentiation stages of normal B cells. Keywords: miRNA, normal mature B cells
