A decrease in B cell function and augmentation of NK cell function is observed in (NZB/NZW) F1 (BWF1) mice treated with alpha-galactosylceramide (α-GalCer). (a) Representative histograms obtained by flow cytometry showing the expression of intracellular Toll-like receptor-9 (TLR-9) in splenic F4/80+ CD11b+ macrophages in the vehicle (left) and α-GalCer (right) groups of BWF1 mice. The data represent the mean ± SEM in each group (n = 4 in each group). IgM production by spleen mononuclear cells (MNCs) stimulated with (b) CpG-oligodeoxynucleotide (CpG-ODN) or (c) lipopolysaccharide for 48 hours in each group (n = 4–6 in each group). (d) IFN-γ production by liver MNCs stimulated by CpG-ODN for 48 hours in each group (n = 4 in each group). *p < 0.05 compared with the vehicle group.