Decellularized matrix grafts from placenta chorionic plate for small diameter vascular applications

摘要

The human placenta is deemed to be clinical waste. However, some placental structures, e.g. the vasculature, have a great potential as source for human allogeneic vascular replacement material. Therefore, we established a method for decellularization of vascular tissue from human placenta chorionic plate. Our protocol is based on the combination of an initial freeze-thaw step, a short osmotic pressure treatment step with a hypertonic salt solution and a chemical disruption step using 1 % Triton X-100. Furthermore we apply perfusion in a pulsatile manner through the lumen of the vessels via a custom-made computer controlled perfusion system. The perfusion set-up enabled us to lower the concentrations of the chemicals with a shorter exposure time compared to a non-perfusion process. Complete decellularization was confirmed by histology, scanning electron microscopy and biochemical quantification methods. The used decellularization procedure did not lead to significant changes in collagen content of the decellularized matrix grafts. Moreover, biocompatibility of the decellularized tissue and its ability to serve as an adequate scaffold for recellularization strategies using primary endothelial cells was shown in vitro. To create a nonthrombogenic luminal surface with good healing characteristics, decellularized blood vessels were chemically cross-linked with heparin. Such modified small diameter vessel grafts are currently tested in vivo in a small rodent model.