Grafting of neural tissue in chronically injured spinal cord: influence of the donor tissue on regenerative activity.
BACKGROUND
To determine the influence of different nervous tissue grafts on the regenerative activity of chronically injured spinal cord, an experimental study examining the expression of the proliferating cell nuclear antigen (PCNA) in chronically injured spinal cord subjected to neural grafting was performed.


METHODS
Three months after induced spinal cord injury, paraplegic Wistar rats were subjected to grafting of neural tissue. Grafts consisted of fetal brain cortex, fetal spinal cord, crushed adult peripheral nerve tissue, or fetal brain cortex combined with crushed adult peripheral nerve tissue. Four months later, the spinal cord was removed and the grafted zone was studied by means of immunohistochemical demonstration of PCNA.


RESULTS
Different patterns of PCNA expression were recorded in the different experimental groups. PCNA-immunostained cells in injured spinal cord tissue, mainly ependymal cells and astrocytes, increased when co-transplantation of fetal brain cortex and crushed adult peripheral nerve tissue was used, in comparison to other neural donor tissues. In the grafted tissue, proliferative activity was greater when fetal brain cortex, alone or with peripheral nerve, was used, in comparison to the use of fetal spinal cord or adult peripheral nerve tissue. Nevertheless, the number of PCNA-positive cells does not seem to be influenced by the presence of peripheral nerve tissue in the donor tissue.


CONCLUSIONS
Our present findings suggest the effectiveness of co-transplantation of peripheral nerve tissue and fetal brain tissue in attempts at spinal cord reconstruction after injury.
Zurita
M
M
Neuroscience Research Unit of the Mapfre-Medicine Foundation, Puerta de Hierro Clinic, Autonomous University, Madrid, Spain.
Vaquero
J
J
Oya
S
S
D000818:Animals; D016380:Brain Tissue Transplantation / Q000473:pathology; D002540:Cerebral Cortex / Q000473:pathology / Q000637:transplantation; D005260:Female; D016332:Fetal Tissue Transplantation / Q000473:pathology; D009416:Nerve Regeneration / Q000502:physiology*; D009417:Nerve Tissue / Q000473:pathology / Q000637:transplantation*; D010525:Peripheral Nerves / Q000473:pathology / Q000637:transplantation; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D013116:Spinal Cord / Q000473:pathology / Q000637:transplantation; D013119:Spinal Cord Injuries / Q000473:pathology / Q000601:surgery*
D018809:Proliferating Cell Nuclear Antigen