Perfusion decellularization of whole rat hearts. (A)–(C): Photographs of cadaveric rat hearts mounted on a Langendorff apparatus. Retrograde perfusion of cadaveric rat heart over 12 h using, (A) PEG, (B) Triton-X-100 and (C) SDS. The heart becomes more translucent as cellular material is washed out from the right ventricle, then the atria and finally the left ventricle. (D)–(F) Corresponding H&E staining of thin sections from LV, showing complete decellularization in (F) and incomplete decellularization in (D) and (E). (D) and (E) Hearts treated with PEG or Triton-X-100 retained nuclei and myofibers. Scale bars, 200 mm. (F) H&E staining of SDS-treated heart showing no intact cells or nuclei. Scale bar, 200 mm. All three protocols maintain large vasculature conduits (black asterisks). Note: Ao, aorta; LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle. Source: Adapted with permission from Ott et al. (2008).