FIG. 2.

The decellularization process largely preserves the native structure of porcine lungs. Representative images of native and decellularized wild-type and α-gal KO pig lungs are depicted. (A) Photomicrographs demonstrate qualitative preservation of characteristic structure and major ECM proteins (collagen, elastin) by H&E, EVG, and trichrome stains. Glycosaminoglycan content is qualitatively decreased as assessed by Alcian blue staining. Original magnification 100 × . Representative images from wild-type (n = 33) and α-gal KO (n = 17) pig lungs are shown. (B) Transmission electron microscopy demonstrates comparable appearance of proximal airway, distal airway, and alveolar septal regions in decellularized wild-type and α-gal KO pig lungs (scale bar is indicated on each image). Representative images from a single decellularized wild-type and single α-gal KO lung are shown. Enlargements of the insets for each image demonstrate more detail in residual collagen and elastin fibers (arrows). (C) DNA gels demonstrate minimal residual DNA in decellularized wild-type and α-gal KO pig lungs compared to native controls. A DNA ladder and salmon sperm DNA (positive control) are shown for comparison. Representative gels for native and decellularized wild-type and α-gal KO pig lungs are shown. a, airways; bv, blood vessels; ECM, extracellular matrix; EVG, Verhoeff's Van Gieson; H&E, hematoxylin and eosin. Color images available online at www.liebertpub.com/tec