Nerve xenograft transplantation. Immunosuppression with FK-506 and RS-61443.

An experimental model has been developed to study the potential transplantation of nerve xenografts using the newer immunosuppressive agents RS-61443 and FK-506. Sciatic nerve grafts of 2 cm were transplanted from donor Golden Syrian hamsters into a 0.5 cm gap in the sciatic nerve of recipient Lewis rats. Walking track analysis, somatosensory evoked potentials and histology demonstrated improved regeneration across the nerve xenografts that had been immunosuppressed with RS-61443 and FK-506 compared with non-immunosuppressed controls, but the function never approached that seen in control isografts. Regeneration across nerve xenografts immunosuppressed with FK-506 was better than xenografts immunosuppressed with RS-61443.