Supplementary MaterialsSupplementary File. and and and and and and and 0.05; ** 0.01; *** 0.001 (unpaired 2-tailed test Rabbit Polyclonal to NCoR1 [and and and are is summarized from multiple experiments with similar results. We further investigated antigen-specific GC responses in ShipB (and and and and and and and and and and and and and and and and and and and and 0.05; ** 0.01; *** 0.001; **** 0.0001 (1-way ANOVA with Sidaks multiple comparisons test [test [is summarized from 2 independent experiments with similar results. To test whether the aberrant T-cell profile (with increased T-cell activation and TFH-cell accumulation) is responsible for the impaired GC selection in these models, we adoptively transferred pan-T cells isolated from ShipB mice into T cell-deficient mice (and (encoding CD11c) and and and and and and and and 0.05; ** 0.01; *** 0.001; **** 0.0001 (unpaired 2-tailed test [and and and and and with indicated B-cell subsets in the Diflunisal absence (UT) or presence of 0.3 g/mL of OVA peptide for 84 h. (and and 0.05; ** 0.01; **** 0.0001 (2-way ANOVA with Sidaks multiple comparisons test [and test [and and Diflunisal and and and and and and and and 0.001; **** 0.0001 (unpaired 2-tailed test [and and and and and and and and and and and and and and and and 0.05; ** 0.01; *** 0.001; **** 0.0001 (1-way ANOVA with Sidaks multiple comparisons test [and is summarized from multiple experiments with similar results. CD11c+Tbet+ ABCs Contribute Significantly to Autoantibody Production in ShipB Mice. To investigate whether CD11c+Tbet+ ABCs cells contribute to autoantibody production, their ability to produce anti-dsDNA autoantibody was analyzed. We found that depleting CD11c+ cells from ShipB pan-B cells also depleted anti-dsDNA autoantibody-producing B cells (Fig. 6 and and 0.05; ** 0.01; *** 0.001; **** 0.0001 (unpaired 2-tailed check and and [and Diflunisal and and 0. 05 (unpaired 2-tailed check ideals and [and, linear regression [are summarized from multiple tests. Discussion Our research demonstrates antigen-specific GC reactions are compromised in every tested lupus versions, with minimal differentiation of antigen-specific GCB cells and impaired AAM considerably, highlighting a humoral immunodeficiency which has not been valued sufficiently. Our data claim that this defect isn’t because of the decreased development of GC or GCB cells, but rather due to the lack of efficient affinity-based positive selection for antigen-specific GCB cells, the basis of the production of pathogen-specific affinity-matured antibodies. Strikingly, our data support that this defect can be triggered by excessive CD11c+Tbet+ ABCs, a non-GCB cell subset. In ShipB mice, a B cell-intrinsic lupus model, excessive CD11c+Tbet+ ABCs emerge before deregulated T-cell activation and TFH differentiation, as well as autoantibody production. Our study shows that excessive CD11c+Tbet+ ABC differentiation in ShipB mice promotes deregulated T-cell activation and TFH differentiation through their potent antigen-presenting function and consequently compromises GCB-cell selection and AAM. Consistently, it has been shown that B cells are required for TFH differentiation and maintenance (66, 67). Our observation that depleting CD11c+ cells attenuates established TFH responses in Bm12 cGVHD mice suggests that CD11c+ ABCs contribute to TFH maintenance. Notably, it has been reported that selectively depleting CD11c+ B cells leads to 80% reduction in TFH cells (72), which was interpreted as the impact of depleting GCB cells based on the observation that a small fraction (20%) of GC B cells express CD11c (72). In the context of our study, these data can be alternatively interpreted as the impact of depleting CD11c+ ABCs, which constitute the majority of CD11c+ B cells (50 to 80%, as compared to 10% for GC B cells). Our model is further supported by the observation that inhibiting CD11c+ ABC differentiation in ShipB mice by ablating B cell-intrinsic MyD88 not only normalizes TFH differentiation but also rescues GC selection and AAM. B cell-intrinsic MyD88 has also been reported to be critical for GCB-cell and antibody responses to TLR ligand-containing vaccines/immunizations (73, 74), as well.