Transcriptome of TACI KO and WT mouse marginal zone and follicular B cells

The mature peripheral B cell compartment consists of follicular (FO) and marginal zone (MZ) B cells, which mature from transitional B cells in the spleen and mount T-dependent and T-independent antibody responses, respectively. TACI (Tnfrsf13b) is a member of the TNF-receptor superfamily expressed on mature and transitional B cells, with highest expression on MZ B cells and plasma cells, which is activated by the cytokines BAFF and APRIL. BAFF also stimulates the related receptor BAFFR, which provides signals that are essential for mature B-cell survival. Previous studies of TACI-/- mice have observed that TACI-deficiency leads to an expansion of mature B cells, and therefore it has long been thought that TACI is a negative regulator of mature B-cell survival. However, TACI-/- mice also have elevated levels of BAFF, therefore the B-cell hyperplasia phenotype in TACI-/- mice is most likely a cell-extrinsic effect due to increased BAFF-BAFFR signalling in TACI-/- B cells. To investigate the cell-intrinsic role of TACI, we generated mouse mixed bone marrow chimeras from TACI-/- and WT mice and studied the effect of TACI loss in vivo, without the confounding factor of increased BAFF. Here, we have analysed the transcriptomes of TACI KO and TACI WT marginal zone and follicular B cells by RNAseq.