*4.3. DNA Measurements*

Decellularized lung tissue was quantified for residual double stranded DNA (dsDNA) using fluorescent nucleic acid staining (Thermo Fisher Scientific, P7589). Lung tissue slices were freeze dried and homogenized with 0.1 mm zirconia silica beads (Thermo Fisher Scientific, Waltham, MA, USA, cat.no. 3488) in a fast prep bead beater (MP fastprep96, Nordic Biolabs, Täby, Sweden). Samples were centrifuged at 6000× *g* for 3 min and supernatants were analyzed for dsDNA quantification according to manufacturer's instructions.
