(A) Anti-BST2 or the isotype rat IgG was i.p. administered into 4-week-old female NOD mice, 3 times weekly for 3 weeks. Immunofluorescence staining images show the detection of serum autoantibodies, measured by the HEp-2 human epithelial cell substrate slides, in mice aged 10 weeks (scale bar = 50 μm). The two images shown for the anti-BST2 treatment group represent serum samples from two of the NOD mice in this group. Bar graphs show the fluorescence intensity of autoantibody staining of the 1:40-diluted sera, left, and the autoantibody titers, right. (B) Relative level of anti-M3R in the sera as determined by ELISA. All data are representative or the average of analyses of 6 mice for each group.