For your 3D models of the airway epithelium air-liquid interface (ALI) cultures, is it possible to grow epithelial cells on fibroblasts? Or do you have other methods to generate stromal cells?

Answer

Yes, you can co-culture the airway epithelial cells with human airway fibroblasts. The human airway fibroblasts can be seeded onto opposite side of a transwell insert membrane so the fibroblasts are submerged in the PneumaCult™-ALI medium within the bottom chamber and epithelial cells in the apical chamber are at air-liquid interface.

It should first be noted that stromal cells are not required for achieving a well-differentiated pseudostratified airway epithelium at air-liquid interface when using PneumaCult™ media. This defined media system can be used to generate a high-integrity epithelial layer at the air-liquid interface in the absence of other cell types. If desired, however, you can co-culture airway epithelial cells with human airway fibroblasts, in order to investigate the interactions and signalling between these cell types. In this case, the human airway fibroblasts can be seeded onto the basal side of a cell culture insert, such that the fibroblasts are submerged in PneumaCult™-ALI Medium in the basal chamber after air-lift while the epithelial cells are exposed to the air in the apical chamber. There are also several other methods for co-culture of airway epithelial cells with other cells types, such as mesenchymal stem cells (Carbone et al.), to enable interrogation of the signalling interaction between those tissue types.