Acidic glycoproteins produced by the mucous cells of the bronchial submucosal glands in the fetus and child: A histochemical autoradiographic study

Abstract

The adult mucous cells of the submucosal glands of the trachea and bronchus produce four varieties of acidic glycoproteins. Only one of these, the heavily sulphated type, is produced in the fetus. The percentage of mucous cells producing sulphated mucin falls, and the percentage producing sialomucin rises to the normal adult levels over the first 2–3 years of life. The predominance of sulphated mucin in the fetus is not one aspect of a general inability to produce sialomucin in fetal life, nor is it the consequence of an inactive resting phase in the mucous cell activity. The significance of these findings is discussed.