FIG. 3.
ECM disruption as a result of freeze drying. (A) H&E staining of native tissue reveals highly dense undisrupted nature of collagen fibers. (B) Decellularization does not disrupt fibers (C) H&E staining shows that Tf=−10°C causes major collagen fiber disruption in decellularized scaffolds; black arrows indicate fully ruptured fibers; and white arrows display areas of nonuniform drying. (D) Less fiber damage was visible in Tf=−40°C decellularized scaffolds, but more uniform drying was apparent. (E) SF Tf=−40°C customized scaffolds retained a similar configuration of ECM as non-freeze-dried scaffolds. (F) Verhoff Van Gieson staining of decellularized scaffold in the Tf=−40°C group displayed disruption of the elastin network (elastin fibers stain black). Fragmentation of the elastin sheets was visible (white arrows). Scale bars in A–C indicate 20 μm and 50 μm in D. Color images available online at www.liebertpub.com/tec