Fig. 5

Systemic lupus erythematosus (SLE) pre-naïve B cells were defective in producing interleukin-10 (IL-10) and promoted robust CD4⁺ T-cell activation. a Representative contour plot showing the frequencies of IL-10-producing B cells from an SLE patient, measured as described in Fig. 1b. b Comparison of the frequencies of IL-10-producing B cells between six patients with SLE and 10 healthy donors (cumulative data from 6 independent experiments). c Supernatants from cultures as described in (b) were tested for the presence of IL-10 by enzyme-linked immunosorbent assay. d Representative histogram comparing CD80, CD86, CD54, and HLA-DR expression on pre-naïve B cells from a healthy individual and an SLE patient, obtained as described in Fig. 3a. e Comparison of mean fluorescence intensity of CD80, CD86, CD54, and HLA-DR expression of pre-naïve B cells from six healthy individuals and three SLE patients on days 0–2 (cumulative data from three independent experiments). Data are expressed as mean ± standard error. f Representative histogram showing proliferation of T cells in co-culture with B cells from two SLE patients and two healthy donors. Proliferation of T cells was determined by carboxyfluorescein succinimidyl ester (CFSE) dilution. *P < 0.05, **P < 0.01, ***P < 0.001. IFN-γ interferon-gamma, MFI mean fluorescence intensity