Described are tissue graft constructs that include submucosa and other extracellular matrix materials that incorporate a number of exogenous proteins. Further described are methods for making tissue graft constructs that include stripping endogenous heparin binding proteins from a porcine graft material and thereafter binding one or more human growth factors to the native heparin molecules that are retained within the graft material. Such graft materials may be used in methods for the treatment of wounds in patients.
