FIG. 1.

Twenty-four-hour de-cellularization protocol effectively removes cells and maintains architecture but increases alveolar spacing. (A) Gross histology of the normal and de-cellularized lung. The addition of methylene blue demonstrates patency of the construct immediately and 7 days after de-cellularization. (B) Histology of 50-h and 24-h de-cellularization protocols compared to the normal lung with gomori trichrome, H&E, and alcian blue staining. Representative images for all conditions are shown (20×magnification). (C) Nuclei count and the alveolar mean cord length are calculated after 24-h de-cellularization (n=5. *p<0.05). (D) Transmission and scanning electron microscopy of the 24-h de-cellularized lung compared to the normal lung. H&E, hematoxylin & eosin. Arrows indicating disrupted basement membrane. Color images available online at www.liebertonline.com/tec