7. The recommended seeding density is 5000–20,000 cells per

cm².

8. The formula to calculate the final volume depends on the

specific type of chamber used. Cells/μL ¼ Average number of

cells per small grid  chamber multiplication factor  dilution.

9. The bioreactor provides continuous rotation of the tracheal

bio-scaffold, exposing cells to a covering film of alternating

gas and liquid phases.

Acknowledgments

This research was funded by Carraresi Foundation. The Authors are

members of the COST Action CA16119 In vitro 3-D total cell

guidance and fitness (CellFit) and of the Trans-COST Actions

Task-Force on Covid-19.

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