Table 1: Modulation of stem cells or dopaminergic (DA) cells with combined cellular transplantation in PD.

Type of transplanted cellsAnimal modelSignificanceReference

Mouse fetal DA neuronsMouse mesencephalic NSCs overexpressing human glial-derived neurotrophic factor (GDNF-mNSCs)6-OHDA rat Apomorphine-induced rotation was reduced by cotransplantation of fetal DA neurons with mNSCs genetically modified to overexpress GDNF, which supports differentiation into DA cells and their survival[66]

Human embryonic NSCMacaque autologous Schwann cells (SCs)6-OHDA macaque Gomez-Mancilla dyskinesia score in the group of cotransplantation with SCs and NSCs was significantly lower than the control group. SCs harvested from the autologous peripheral nerves can avoid rejection[67]

Human umbilical cord-derived MSCsHuman dermal fibroblastsMPTP rat Fibroblasts may be common cell contaminants affecting purity of MSC preparations and clinical outcome in stem cell therapy protocols[68]

Rat embryonic DA neuronsRat Schwann cells (SCs) overexpressing basic fibroblast growth factor (FGF-2)6-OHDA rat Cotransplantation of DA neurons and FGF-2 overexpressing SCs differentially affects survival and reinnervation. Behavioral recovery underlines the necessity of direct contact between FGF-2 and DA neurons[69]