Fresh Venous Allografts as Arterial Substitutes in Dogs: The Importance of Donor-Recipient Tissue Compatibility

Abstract

Fresh venous allografts were investigated in dogs matched according to donor-recipient tissue compatibility, either originating from the same litter or chosen at random (pound dogs). Five centimeter long segments of femoral vein were interposed as carotid substitutes in an autografting and allografting manner between paired dogs. During a 5-month implantation period, donor-specific antibody development was measured in the recipient serum by a flow-cytometric assay using cultured donor vascular endothelial cells. Autografts and allografts were investigated in terms of patency, histopathology, and endothelial cell function. Fifteen of 16 autografts remained patent. Allografts between littermate dogs, whether compatible or incompatible, showed no donor-specific antibody development and were all patent at retrieval.

Compatible and incompatible allografts in littermates did not show any difference in prostacyclin (PGI,)/thromboxane A, (TXA,) ratios. In pound dogs, both compatible allografts were patent and one dog developed donor-specific antivascular endothelial cell antibodies. Among incompatible dogs, antibody formation was detected at I month in jive of six recipients and graft patency was as follows: two partial thromboses, two stenoses, and two patent grafts. The PGIJTXA, ratio was significantly lower in incompatible allografts than in compatible ones (p =. 028). These results show the importance of donor-recipient histocompatibility matching in improving the outcome of vein allografts.

Key Words:

• vein grafts
• arterial substitute
• histocompatibility