Selection of an immunohistochemical panel for cardiovascular research in sheep.

Large animal research, often required as a final phase before commencing clinical trials for devices, has generally been hampered by the lack of appropriate tools to compare it with either initial small animal tests or to later evaluation in humans. Setting out to tissue engineer heart valves, we were particularly struck by the limited availability of immunohistochemical markers for sheep tissue, despite sheep being the FDA-approved animal for heart valve testing. This paper, therefore, aims to compile the available knowledge and extend the marker list with antibodies cross-reacting with sheep tissue.

The remodeling of cardiovascular bioprostheses under influence of stem cell homing signal pathways.

Optimizing current heart valve replacement strategies by creating living prostheses is a necessity to alleviate complications with current bioprosthetic devices such as calcification and degeneration. Regenerative medicine, mostly in vitro tissue engineering, is the forerunner of this optimization search, yet here we show the functionality of an in vivo alternative making use of 2 homing axes for stem cells. In rats we studied the signaling pathways of stem cells on implanted bioprosthetic tissue (photooxidized bovine pericardium (POP)), by gene and protein expression analysis.