1986 Volume 8 Issue 2 Pages 191-197
In order to study pulmonary defence mechanism and mucociliary transport system reflected by morphological alterations in Mycoplasma pneumoniae infections, ultrastructural observations were made on hamster tracheal epithelium inoculated with Mycoplasma pneumoniae FH strain. One hour post-inoculation, M. pneumoniae attached to the ciliary membrane with a characteristic tip were identified accompanied by bleb formation of cilia and destruction of ciliary membrane. This tip was composed of a dense central core surrounded by a lucent space enclosed by the organism's limited membrane. Seventy-two hours after inoculations, the tracheal epithelium showed clumping of microvilli, extruded fragments of ciliated cells, and reduction in the density of cilia when compared with uninfected controls. These degenerative changes of epithelial cells progressively developed, and marked sloughing of cilia with completely denuded appearance of the cell surface was observed 14 days after infections, which may responsible for upper respiratory tract symptoms. In the regenerative process following, the density of cilia gradually increased by 20 and 30 days after infection, accompanied by the appearance of many protruding axonemes with a single ciliary membrane. This finding suggested the formation of compound cilia, and because these cilia are considered to be immobile, pulmonary mucociliary transport may be disturbed, with resultant prolonged cough and sputum in patients of Mycoplasma pneumonia.
