FUNCTIONAL RECOVERY IN HEMIPARKINSONIAN PRIMATES TRANSPLANTED WITH POLYMER-ENCAPSULATED PC12 CELLS

Cross-species neural grafting of cell lines immunoisolated by a permse lective polymer membrane represents a promising source of neuroactive molecules for the treatment of neurodegenerative diseases. Utilization of a cell line of xenogeneic origin is advantageous since the transpl anted cells will be rejected by the host immune system in case of brea kage of the immunoisolating envelope. Polymer-encapsulated PC12 cells, a dopaminergic cell line derived from a rat pheochromocytoma, were tr ansplanted in five Macaca fascicularis monkeys which had been previous ly rendered hemiparkinsonian by a unilateral carotid injection of 1-me thyl-4-phenyl- 1,2,3,6-tetrahydropyridine. Well-preserved, tyrosine hy droxylase positive encapsulated PC12 cells were observed in the lesion ed striatum for up to 5 months after implantation. Four out of five mo nkeys which received polymer-encapsulated PC12 cells showed significan t behavioral improvement, whereas three monkeys implanted with either encapsulated bovine chromaffin cells or empty polymer envelopes showed no amelioration. (C) 1994 Academic Press, Inc.