Am. J. Respir. Cell Mol. Biol.,
Volume 20, Number 2, February, 1999 312-318
In Vitro Reconstitution of the Tracheal Epithelium
Yukio
Goto,
Yoshiko
Noguchi,
Akihiro
Nomura,
Tohru
Sakamoto,
Yukio
Ishii,
Soji
Bitoh,
Colin
Picton,
Yoshiji
Fujita,
Teruo
Watanabe,
Shizuo
Hasegawa,
and
Yoshiyuki
Uchida
Tsukuba Research Laboratories, Nippon Glaxo Ltd.; Department of Pulmonary Medicine, Institute of Clinical Medicine; and
Department of Pathology, Institute of Basic Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
We have developed a unique in vitro reconstitution system for tracheal epithelia of guinea pigs. In the system, a human amnion membrane was used as a basement membrane and the tracheal epithelial cells were
cultured on the epithelial side of the membrane. Three weeks later, the tracheal fibroblasts were co-cultured on the serosal side of the amnion membrane and the culturing was continued for an additional 10 d.
The morphology of the cultured epithelial cells consisted of a pseudostratified columnar ciliated epithelium from cuboidal ciliated epithelium during the last 10 d of the culture period. Epithelial cells included
both goblet-like and basal cells. In addition, the frequency of each type of differentiated cells was almost
identical to that of in vivo tracheas. Interestingly, the same results were obtained when the conditioned medium of the tracheal fibroblasts was used instead of the fibroblasts themselves. These results suggest that
epithelial-mesenchymal interaction is likely involved in growth and differentiation of epithelial cells in
vivo in a soluble factor(s)-mediated manner. As well as the epithelial cells, the fibroblasts also formed a
multilayer during the last 10 d of co-culturing. This indicates that in vitro reconstitution of tracheal epithelia is achieved without addition of any exogenous growth or differentiation factors. The reconstitution system is shown to be useful for investigating the cellular and molecular interaction of epithelial and mesenchymal cells. Possible applications of the culture system and possible factors involved in growth and
differentiation of epithelial cells are discussed.