Vein replacement with fresh vital veins: a comparison of transplantation in RT-1-different rat strain combinations.

Transplantation of the intrathoracic inferior vena cava into the abdominal inferior vena cava of the recipient was performed in inbred rat strains of the following combinations: Syngeneic F344 leads to F344, RT-1-identical allogeneic LEW leads to F344, and RT-1-different allogeneic CAP leads to F344. In the RT-1-different combination subgroups with presensitization (blood, skin) were formed. The transplanted veins were evaluated at different times, macro- and microscopically. To test humoral immunology reactivity, we used a modified hemagglutination test, to analyse cell-mediated reactivity, subsequent skin grafts. The following results were obtained: 1) Aside from sporadic mononuclear cells caused by the operation technique, syngeneic vein grafts do not show any macroscopically visible and microscopically detectable changes. 2) Weakly allogeneic vein grafts do not lead to microscopically detectable changes in the graft. Strongly allogeneic vein grafts cause temporary mononuclear cell infiltration, which subsides within 21 days, without influencing the morphologic structure of the vessel wall. 3) In the RT-1-identical allogeneic strain combination, only accelerated skin graft rejection time indicates systemic sensitization, in the strongly allogeneic system, the increase of hemagglutinating antibodies also does this. 4) In both the RT-1-identical allogeneic strain combination and the RT-1-different allogeneic one, a proven sensitization does not lead to a permanent morphologic alteration. 5) Only presensitization with strong antigens (skin) leads to a macroscopically visible, as well as microscopically detectable, rejection reaction.