Semi-quantitative 3-D immunomicroscopy for small intestinal production and secretion of amyloid-β and apolipoprotein B, and plasma amyloid-β. The production within the enterocytes and secretion into the lacteal of amyloid-β (Aβ) and apolipoprotein (apo) B were determined with 3-D quantitative immunomicroscopy in the small intestine of mice maintained on low-fat (LF) control chow or diets enriched in saturated fats (SFA) with/without probucol for 3 months (3 M) and 12 months (12 M). (A) The mean voxel intensity of small intestinal villi Aβ or apoB are expressed per DAPI voxel intensity. One-way ANOVA followed by Tukey’s post hoc test was performed and the significance is indicated with * (p < 0.05, n = 8). (B) The plasma concentration of Aβ was measured with ELISA. One-way ANOVA followed by Tukey’s post hoc test was performed to compare the difference of total plasma Aβ, and the significance is indicated with alphabetical letters (p < 0.05, n = 8). (C) Correlation coefficient between intestinal Aβ or apoB with cerebral IgG/apoB extravasation are also shown. Correlation coefficient was determined with Pearson’s analysis (n = 24). (D) Correlation coefficient between intestinal Aβ or apoB with neuroinflammatory GFAP/COX-2 are also shown.