Procurement, isolation, expansion, and characterization of hfSC, as well as assessment of patients' immune response to hfSC grafting, were performed at Celavie Biosciences, LLC (Oxnard, CA USA). Patient selection, pre- and post-surgery neurological, neuropsychological, and MRI evaluations, as well as stereotactic surgery and post-surgery care, were performed at Hospital Angeles del Pedregal (Mexico City, Mexico). Synthesis of radiopharmaceuticals and PET imaging were carried out at the Radiopharmacy-Cyclotron Unit of the Faculty of Medicine, Universidad Nacional Autonoma de Mexico (Mexico City, Mexico). Eight patients with moderate to advanced PD were selected for this trial. One of the patients was lost to follow up due to reasons unrelated to this study. Subjects that completed follow up were 2 females and 5 males, with ages ranging between 43-74 years (mean age 56 years).