Figure 1.

Immunoperoxidase localization of the 13A4 antigen (prominin) in the neuroepithelium and kidney tubules. Triton X-100-permeabilized cryosections (8 μm) of paraformaldehyde-fixed telencephalic neuroepithelium of a 12-day-old mouse embryo (A) and adult mouse kidney cortex (B) were stained with mAb 13A4 (1 μg/100 μl) followed by peroxidase-coupled goat anti-rat IgG/IgM and observed using Nomarski optics. In A, the apical and the basal side of the neuroepithelium are at the top and bottom, respectively. Immunoreactivity is confined to the apical, ventricular side. In B, most tubules are cross-sectioned. Immunoreactivity is restricted to their apical, lumenal side. (Bars = 20 μm.)