In a previous report,1 the early results of implantation of enzymatically digested bovine heterografts into the abdominal aorta of dogs were described. Bovine arteries were stripped of most of their parenchymatous proteins by controlled enzyme action, leaving tubular prostheses composed mostly of collagen. These tubes were implanted into dogs as aortic substitutes in the hope that, with most of their immunologically reactive proteins removed, the implants would be better tolerated by the host while yet maintaining their effectiveness as arterial substitutes. Short-term observations seem to corroborate this hypothesis, and histological comparisons of treated and control heterografts after implantation indicate a markedly diminished host reaction to the enzyme-digested vessel.
In a second report,2 the physical characteristics of the elastica and collagen components of the arterial wall were investigated. It was shown that collagen derived from arteries by digestion with the enzyme ficin is highly resistant to mechanical stress, whereas
ROSENBERG N, HENDERSON J, LORD GH, GAUGHRAN ERL, DOUGLAS JF. Use of Enzyme-Digested Heterografts as Segmental Arterial SubstitutesIII. Follow-Up Observations on Two-Year-Old Aortic Implants. AMA Arch Surg. 1958;76(2):275-281. doi:10.1001/archsurg.1958.01280200097011