Addition of fresh blood to intrastriatal grafts of embryonic mesencephaloninto the hemiparkinsonian rat does not impair the survival of grafted dopaminergic neurones

Cell transplantation therapy for Parkinson's patients, although seen to bri ng benefit to some patients during first clinical trials, remains impractic able on a large scale, in part because of the poor survival of the dopamine rgic neurones transplanted. The loss of dopaminergic neurones occurs rapidl y over the first 1-2 days after transplantation, in response to factors int rinsic to the host brain. Here we investigated whether contamination of the grafted cell suspension with blood during the transplantation procedure ma y be one factor responsible for the poor survival of DA neurons within the graft, possibly through factors such as free iron or complement. 6-Hydroxyd opamine lesioned rats were grafted with 2 mu l suspension of dissociated E1 4 ventral mesencephalon to which 1 mu l blood or 1 mu l grafting medium was added. After 6 weeks, there was no significant difference in the number of surviving DA neurones in the two groups. We conclude that contamination of grafts with blood is not a major factor responsible for the extensive deat h of dopaminergic neurones within them. (C) 1999 Academic Press.