Methylene blue-stained ACF (a, c) and corresponding HID-AB stain (b, d). ACF with enlarged round shaped crypts (a, b) appeared to have increased deposition of HID or more sulphomucin whereas ACF with slit-like crypts (c, d) demonstrated little to no HID staining with variable amounts of AB stain, i.e., sulphomucin-depleted. e Methylene blue-stained colon with three ACF showing variable crypt morphology. Round crypts (arrow), slit-like crypts (diamond) and spiral crypts (arrowhead). f Corresponding HID-AB-stained colon. Round crypts favored both HID and AB stains (arrow). Slit-like crypts typically demonstrated AB only with scant HID stain (diamond). Spiral crypts showed absence of HID and scant AB stain. Bars = 100 μm.