Abstract
We report on the development of a new model of alveolar air-tissue
interface consisting of an array of suspended hexagonal monolayers of
gelatin nanofibers supported by microframes and a microfluidic device
for the patch integration. The suspended monolayers are deformed to a
central displacement of 40-80 μm at the air-liquid interface by
application of air pressure in the range of 200-1000 Pa. With respect to
the diameter of the monolayers that is 500 μm, this displacement
corresponds to a linear strain of 2-10% in agreement with the
physiological strain range in the lung alveoli. The culture of A549
cells on the monolayers for an incubation time 1-3 days showed viability
in the model. We exerted a periodic strain of 5% at a frequency of 0.2
Hz during 1 hour to the cells. We found that the cells were strongly
coupled to the nanofibers, but the strain reduced the coupling and
induced remodeling of the actin cytoskeleton, which led to a better
tissue formation. Our model can serve as a versatile tool in lung
investigations such as in inhalation toxicology and therapy.