The invention provides a xenograft formed of a soft tissue for implantation into a human comprising a portion of the soft or bone tissue from a non-human animal, wherein the portion includes a plurality of extracellular components, a plurality of substantially only dead cells, and an aldehyde in an amount ranging from about 0.01 % to about 0.10 % crosslinking a plurality of proteins of the extracellular components, the extracellular components and the dead cells having substantially no surface carbohydrate moieties which are susceptible to glycosidase digestion, and whereby the portion is substantially non-immunogenic and has substantially the same mechanical properties as a corresponding portion of the native soft or bone tissue.
