PERMEABILITY OF CULTURED NORMAL BRONCHIAL EPITHELIUM TO FINE NANO-PARTICLES

• Published in: JIBI INKOKA TEMBO Vol. 49; no. Supplement1; pp. 32 - 36
• Main Authors: Takano, Hiroshi, Fujigaya, Takumi, Itoh, Masayuki
• Format: Journal Article
• Language: Japanese
• Published: Society of Oto-rhino-laryngology Tokyo 2006
• Subjects: cultured cell sheet; human respiratory model; nanometer-size particles; normal bronchial epithelium cell; transepithelial permeation
• ISSN: 0386-9687; 1883-6429
• DOI: 10.11453/orltokyo1958.49.Supplement1_32

Transepithelial permeation of nanometer-size particles was investigated by cultured sheets of normal bronchial human and rabbit epithelium. The cultured sheets of normal bronchial epithelial cells were obtained in several subculture steps, and the cultured epithelium was evaluated by a transmission electron microscopy for the morphology of the cell sheets and by a transepithelial electrical resistance method to check their thickness. In the cell culture MSAGM was used to grow normal bronchial epithelial cells plated at a density of approximately 106 cells/cm2 on fibronectin-coated filters. The cells were cultured for 10 days to obtain as a 3-dimensional culture sheets whose morphology most closely approximated the morphology of normal human bronchial epithelium in vivo by the air-contact method. Lanthanum hydroxide (LH) particles 2 nm in diameter were used as the nanometer-size particles to test the transepithelial permeability. The results of the TEM analysis confirmed transepithelial permeation of the nanometer-size particles in the intercellular spaces and the goblet cells of the cultured epithelum, and a significantly larger amount of LH in the intercellular spaces. Since the LH was observed at the tight junctions of the bronchial epithelum, the effective pathway for transepithelial permeation of the nanometer-size particles was in the intercellular spaces.