The morphology of ciliogenesis in the developing fetal human respiratory epithelium.
Segmental imaging studies of the respiratory epithelium from human embryos and fetuses of normal karyotype have demonstrated that ciliogenesis and ciliation of the respiratory epithelium starts at 7 weeks of gestation. Ciliated cell differentiation follows a pre-determined pattern of distribution. It starts exclusively in the upper segment of the membranous trachea and spreads distally. Ciliation of the carinal angle takes place at 8 weeks of gestation. Three patterns of basal body formation were identified. The various morphological features encountered are described and compared with those observed in cases of Immotile Cilia Syndrome and other pathological conditions. Ciliation of the respiratory epithelium in the cartilaginous trachea does not take place until after the 12th week of gestation. The morphological findings identified in our case material are in agreement with those observed in the developing respiratory epithelium of other higher mammals.
Moscoso
G J
GJ
Department of Morbid Anatomy, King's College Hospital School of Medicine and Dentistry, London.
Driver
M
M
Codd
J
J
Whimster
W F
WF
D001980:Bronchi / Q000196:embryology / Q000648:ultrastructure; D002923:Cilia / Q000648:ultrastructure; D005314:Embryonic and Fetal Development; D004848:Epithelium / Q000648:ultrastructure; D005260:Female; D006801:Humans; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012143:Respiratory Physiological Phenomena; D012137:Respiratory System / Q000196:embryology / Q000648:ultrastructure*; D014132:Trachea / Q000196:embryology / Q000648:ultrastructure