CILIOGENESIS AND MUCUS SYNTHESIS IN CULTURED HUMAN RESPIRATORY EPITHELIAL-CELLS

The mechanisms for the regulation of ciliogenesis and for the synthesi s of mucus are not well understood. We sought to develop a culture sys tem for differentiating ciliated and secretory types of human respirat ory epithelial (HRE) cells. Dissociated HRE cells obtained from nasal polyps and maxillary sinus mucosa were cultured on type I collagen gel . Cells grown to confluence on collagen gel lost their cilia and exhib ited a flat, squamouslike appearance. After reaching confluence, the c ultured cells with a collagen gel substrate were removed from plastic dishes and floated in the culture medium After 7 days in the floating culture, some cells exhibited several centrioles or basal bodies, whil e others showed secretory granules. The secretory phenotype predominat ed after 7 days. After 14 days in the floating culture, nearly all cel ls were ciliated. The results demonstrate that the differentiation of HRE cells can be induced by floating cultured cells with a collagen ge l substrate in a defined culture medium.