Ease of tissue collection without ethical and immunological problems inherent in allogenic and xenogenic tissue

Much of the early work focused on autologous cellular sources of dopamine

Adrenal Medulla (AM)

Secretes dopamine and other catecholamines

Freed et al. 1981; Freed et al. 1986

Uncertainties about mode of action of AM grafts, limited functional benefits experimentally

Backlund et al. (1985) --> no placebo, but still some slight improvement

Other studies showed modest improvements for limited 18-month period

Hurtig et al. (1989) --> Post-mortem studies showed poor survival of grafted tissue

o Neuopathological study done 16 years after an autologous adrenal medullary transplantation showed few chromogranin A positive cells and complete absence of cells staining for tyrosine hydroxylase (key enzyme in dopamine synthesis) at the graft site. The patient had dervied some clinical benefit from the graft for ~4 years post transplantation. (Kompoliti et al. 2007)

In order to improve graft survival of AM transplants, co-grafts of tissue secreting Nerve Growth Factor (NGF) were investigated

Animal studies used the technique of co-grafting AM with pre-transected peripheral nerve (NGF source) and showed improvement in graft survival and functional recovery

Clinical studies report only modest improvement on Unified Parkinson’s Disease Rating Scale (UPDRS) scores in ‘on’ and ‘off’ phases with increased proportion of time when dopaminergic medication is working, namely the ‘on; phase, with a corresponding reduction in the ‘off’ phase (Lopez-Lozano et al. 1999)

Clinical trials of direct NGF infusion to support AM autografts also show some benefit

High level of morbidity and mortality associated with the techniques involved in the obtainment and transplantation of AM tissue though