Mucociliary Differentiation according to Time in Human Nasal Epithelial Cell Culture

Abstract

In cell culture studies using human nasal epithelial cells, information regarding the state of differentiation, cell phenotype, and gene expression for mucus production would be important to have in relations to different culture time as these factors may vary according to the length of culture period. The primary purpose of this research was to determine whether the number of the ciliated cells increases as a function of differentiation in normal human nasal epithelial (NHNE) cells. When an increase was observed in the number of ciliated cells, we determined the composition ratio of ciliated cells and secretory cells according to the culture duration. At the same time, we also examined the levels of mucin and lysozyme secretion at the same time. The presence of ciliated cells was not evident up to 2 days after confluence. However, 3.1+/-0.2%, 7.4+/-0.5%, and 14.5+/-0.6% of the cells were ciliated 7, 14, and 28 days after confluence, respectively. Meanwhile, the percentage of secretory cells were 35.6+/-2.8%, 32.8+/-2.5%, 32.8+/-2.5%, and 49.4+/-1.4% on the 2, 7, 14 and 28 days after confluence, respectively. The amount of secreted mucin showed an abruptly increasing pattern by the 14th day of confluence, but showed no significant changes thereafter. The amount of secreted lysozyme increased as a function of differentiation. We concluded that in in vitro studies with NHNE cells, the time point of treatment should vary according to the purpose of the study.