Fig. 3.

Cultivation of human nasal mucosal epithelial cells. (A) Spread of nasal mucosal epithelial cells from the explant fragment and quick proliferation were observed after 7 days of culture. (B) The cells that spread from the explants were found to be of polygonal cobblestone shape with morphology typical of epithelial cells. (C) The cells cultured on temperature-responsive cell culture insert were observed to have a steady growth while retaining the cobblestone morphology even after two passages. (D) After a 12-day subculture, all cultured cells reached a confluent state and could be harvested as a single contiguous sheet by lowering the culture temperature from 37 °C to 20 °C.