CROSS-SPECIES TRANSPLANTATION OF PHOTORECEPTORS WITH TACROLIMUS HYDRATE (FK506) TREATMENT

Photoreceptors from normal neonatal or transgenic neonatal mice with n ormally developing retinas were transplanted into the subretinal space s of normal rats. The animals with transplants received either immunos uppressive treatment with tacrolimus hydrate for the first two weeks a fter transplantation or no treatment. At 4 weeks after transplantation , graft survival occurred only in rats treated with tacrolimus. In 7 o f the 12 treated eyes, photoreceptors survived at least 4 weeks after transplantation. Relatively mature outer segments were found only in 2 eyes in which the retinal grafts formed rosettes.