Immunocytochemical localization of choline-phospholipids in postnatal mouse molars

This localization was studied using anti-choline phospholipid monoclonal IgM antibody (MC22-33F). By immunofluorescence, the apical portions of enamel-secreting ameloblasts and dentine-secreting odontoblasts were positively stained with MC22-33F. By immunoelectron microscopy, lysosomes in preodontoblasts, odontoblasts, preameloblasts and ameloblasts as well as matrix vesicles in dentine were strongly stained with MC22-33F. On the other hand, plasma membrane of these cells did not stain with MC22-33F. The frequency of positively reacting lysosomes in ameloblasts and odontoblasts and of matrix vesicles increased with cell maturation and mineral deposition.