Fig. 8From: Interactions between rat alveolar epithelial cells and bone marrow-derived mesenchymal stem cells: an in vitro co-culture modelTransmission electron micrographic images of the alveolar-like structures observed in cultures of AECs in direct contact with BMSCs on day 14. a Alveolar-like structures consist of mesenchymal cells and matrix on the culture insert (asterisk) covered with an epithelial cell monolayer. b A magnification of a rectangle shown in a. At the edge of the bottom of the alveolar-like structures, type II-like cells with lamellar bodies are shown. c Cells with type I-like phenotype. Magnification of the rectangle shown in a. d A magnification of the rectangle shown in b. White arrow heads indicate tight junctions between epithelial cells, and the black arrow head indicates a cellular contact between the mesenchymal and epithelial cells via a small processBack to article page