Rejection of skin allo- and xenografts in the grass frog, Rana temporaria and the edible frog, Rana esculenta.

The fate of orthotopic dorsal skin allo- and xenografts at 22 +!- 2 degrees C in the grass frog, Rana tempororai (Rt) and in the edible frog, R. esculenta (Re) which is an interspecific hybrid of R. ridibunda and R. lessonae. Median survival times (MSTs) in experimental groups Rt in equilibrium Rt, Re in equilibrium Re and Rt comes from Re were 28, 26 and 25 days, respectively. In R. tempororia hosts the significantly shorter viability of xenografts than allogeneic grafts may be caused by the broader spectrum of transplantation antigens of the hybrid donors. In the experimental group Re comes from Rt similar surviva times of sensitizing, second set and third set grafts were observed (24, 22, and 22 days, respectively). The first symptoms of destruction in the grafts of dorsal skin of R. temporaria were visible earlier than in the grafts of dorsal skin of R. esculenta independently of the species of the hosts. Hypotheses which could explain the differences observed are discussed.