Keratins in the developing olfactory epithelia

At embryonic day 14, the supporting cells of the olfactory epithelium already contained tonofilaments which terminated in the desmosomes, and were stained by antikeratin antibodies of RGE53 and MA902, indicating the presence of 45 and 52.5 kDa keratins. The basal cells were identified at postnatal day 1 by the appearance of a few filaments, and stained by PKK2 antikeratin antibody which reacts with 40, 46, 48, and 54 kDa keratins, and by CKB1 antikeratin antibody which reacts with 50 kDa keratin. At postnatal day 14, the basal cells possessed densely aggregated bundles of filaments and reacted with KL1 and MA902 antikeratin antibodies, indicating the appearance of 56 and 52.5 kDa keratins. The basal cells showed a columnar or pyramidal shape changing into a flat shape during postnatal development. The olfactory cells remained unstained by antikeratin antibodies throughout their development.