Fig. 4: B cell activation by DS plasma and stimulated T cells.
From: Autoimmunity in Down’s syndrome via cytokines, CD4 T cells and CD11c+ B cells
a,b, Plasma cell differentiation (a) and secreted IgG in the supernatant (b) after culture for 4 days of sorted HC naive or CD11c+ B cells in the presence of BAFF, IL-2, IL-10, IL-21, the TLR7/8 ligand R848 with or without IFNγ. n = 3 biologically independent samples. Norm., normalized. c, Correlation of CD11c+ B cell and plasmablast frequencies in adults DS (n = 12) and age-matched HC individuals (n = 8). d, Plasma cell differentiation after culture for 6 days of sorted HC naive B cells in the presence of BAFF, IL-2, IL-10, IL-21, R848 and IgG-depleted plasma from HC individuals (n = 2) or individuals with DS (n = 4). e, Magnetic-activated cell sorting (MACS)-isolated naive B cells from a healthy donor were cultured for 3 days with BAFF, IL-2, IL-21, R848, anti-IgM and plasma of HC individuals or individuals with DS in the presence of a combination of antibodies blocking IFN-I, IFN-II, IL-6 and TFNα signalling, in triplicates. Significance was assessed using two-tailed unpaired t-tests. Data are mean ± s.e.m. The results are representative of two independent experiments with n = 2 donors per group. f–h, Co-cultures containing T cells activated with IL-6, IL-2, both or polarized into TH1 cells with IL-2, IL-12 and anti-IL-4 together with MACS-isolated naive B cells from the same donor, run in triplicates. The frequency of plasmablasts (f) and extracellular CD11c induction (g) and downregulation of CD21 expression (h) in non-plasmablast B cells after co-culture for 3–6 days. Significance was assessed using one-way ANOVA with Tukey’s post hoc analysis. i,j, CD11c induction (i) and plasmablast differentiation (j) in naive CD11c− B cells isolated from controls (n = 4) or individuals with DS (n = 2) after 3 days of co-culture with CD4 T cells isolated from the same donors (syngeneic cultures). For b, d and f–j, data are mean ± s.d.
