New technique for chest opening in mice: U-sternotomy

In cardiac xenotransplantation, transfections with recombinant adeno-associated viruses could be a promising way of modulating the cardiomyocyte genome. Proteins like TRAIL, hDAF, Il-10, Il-4, and beta-galactosidase may be expressed on cardiomyocyte surfaces in order to prevent cellular rejection processes. However, after intracoronary perfusion with transfecting viruses, it takes up to 4 weeks before expression of the transgene can be detected. Mouse models have been established to create reliable transfection protocols. Currently, the major problem involves performing the intraaortic injection in mice without causing a lethal pneumothorax. Here we describe a new technique for chest opening to safely reach the mouse ascending aorta without opening the pleural space. This U-sternotomy reduces the risk of animal death and therefore the amount of quite expensive virus solutions needed.