Simple, low-cost, and well-performing method, the outgrowth technique, for the isolation of epithelial cells from nasal polyps

ABSTRACT Objectives Epithelial cells are an important part of the pathomechanism in chronic rhinosinusitis with nasal polyps. It is therefore essential to establish a robust method for the isolation and culture of epithelial cells from nasal polyps to enable further research. In this study, the feasibility of the outgrowth technique for the isolation of the epithelial cells from the nasal polyps was evaluated. Methods The outgrowth technique was performed to isolate the epithelial cells. Proliferation was evaluated up to the 3rd passage. Epithelial cells were identified and differentiation and proliferation were evaluated using flow cytometry with anti-cytokeratin, anti-p63, and anti-Ki-67. A functionality test was assessed by determining type 2–relevant proteins using ELISA, representatively, interleukin-33 and periostin. Results Using the outgrowth technique, epithelial cells could be isolated from all tissue samples. Isolated epithelial cells showed a proliferation rate of approximately 7- to 23-fold every 6 days up to the 3rd passage. Over 97% of isolated cells were shown to be cytokeratin- and p63-positive, and over 86% of them were Ki-67–positive in flow cytometry. Interleukin-33 and periostin were detectable in the supernatant. Conclusions We introduce a simple, low-cost, and well-performing method for isolating epithelial cells from nasal polyps with the outgrowth technique.