Oxisuran: influence on allograft rejection and graft versus host reactivity in chickens and mice.

Oxisuran, a reported differential suppressant of cell-mediated immunity in several mammalian species, was evaluated for its capacity to prolong allograft survival and reduce graft versus host reactivity in chickens. In addition, the capacity of oxisuran to modulate cell-mediated immunity in mice was reappraised. In the chicken, the administration of 50, 100, or 1000 mg of oxisuran/kg body weight did not significantly prolong allograft survival. Furthermore, graft versus host (GVH) reactivity was not significantly diminished following treatment with 50 or 100 mg of oxisuran/kg body weight; however, GVH reactivity was significantly suppressed after administration of a high dose, 1000 mg of oxisuran/kg body weight. In mice, 100 mg of oxisuran/kg body weight slightly prolonged the survival of H-2a allografts on H-2d recipients, but it did not significantly alter GVH reactivity. Thus, the capacity of oxisuran to significantly suppress cell-mediated immune functions can be questioned at least in the species studied.