Optimum conditions for successful transplantation of immature rat retina to the lesioned adult retina.
We have previously reported the successful transplantation of neonatal rat retina to the lesioned retinas of adult host rats. The current studies provide a much more in-depth evaluation of the optimal conditions under which successful grafting can be achieved. Utilizing the same surgical approach and techniques as in our earlier studies, the variables of host lesion conditioning and donor age were investigated. The grafts were evaluated for survival, location, and degree of achievement of selected histological characteristics. The latter category was organized into an evaluation index (E.I.) which provided a consistent system of scoring for purposes of inter-group comparisons. In order to study the effects of lesion conditioning, neonatal grafts were delivered into fresh (0), 1, 2, 4, and 8 week conditioned lesions. Excellent survival and placement were observed at all conditioning times examined. Even the E.I. failed to reveal any statistically significant differences among the lesion conditioning groups. However, there was the suggestion of reduced scarring in the older, more stable lesion groups. The second portion of the study, dealing with donor age, involved the transplantation of E14, E16, E20, PN1, and PN10 retina into freshly lesioned sites in the host retina. Again the result was excellent overall graft survival and placement in all groups. The E.I. score, however, revealed highly significant differences between PN10 grafts and those from all other groups tested. These differences were revealed for all histological criteria with the exception of non-neuronal barrier formation. These studies show the utility of the current model for the repair of retinal lesions over an extended post-traumatic period as well as revealing the wide developmental window for harvesting retinal tissue for the purpose of intravitreal transplantation.
Blair
J R
JR
Department of Anatomy, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, NC 27103.
Turner
J E
JE
D000375:Aging; D000818:Animals; D006085:Graft Survival; D008297:Male; D008855:Microscopy, Electron, Scanning; D051381:Rats; D011919:Rats, Inbred Strains; D012160:Retina / Q000254:growth & development / Q000637:transplantation* / Q000648:ultrastructure