Pathogenicity of Mycoplasma Pneumoniae in Hamster Nasal Organ Culture

Abstract

Mycoplasma pneumoniae was inoculated into organ cultures of hamster nasal mucosa and trachea in order to observe the growth curve of the organisms, changes in the ciliary activity, and histological findings. M. pneumoniae cells proliferated in the culture medium during the incubation. A relationship between the inoculum size of mycoplasmas and cilia-stopping effect was observed. Formalin-inactivated mycoplasmas did not affect the ciliary activity of nasal mucosa at all. Histopatho-logically, the epithelial cell layers were flattened and cilia were deficient in cultures showing high ciliary-stopping activities. Mycoplasmas were found to have been grown and attached to cilia and epithelial cells when examined by electron micrography. The nasal mucosa organ cultures were more sensitive to the cilia-stopping effect of M. pneumoniae than were the tracheal mucosa organ cultures. The relationship between the pathogenicity of M. pneumoniae in human sinusitis and their cilia-stopping effect on nasal mucosa is discussed.