Therapeutic effect of neural progenitor cells expanded in the 3D nano-engineered Nichoid substrate in a Parkinson’s disease preclinical model

INTRODUCTION: In regenerative medicine, biomaterials have been used to create 3D micro scaffolds, such as the one named “Nichoid”, which mimics the biomechanical characteristics of stem cell niches. The aim of this study was to investigate: i) the proliferation, differentiation and stemness properties of neural precursor cells (NPCs) following their cultivation inside the Nichoid substrate; ii) the therapeutic effect and safety in vivo of NPCs cultivated inside the Nichoid in preclinical experimental model of Parkinson’s Disease (PD). METHODS: Nichoids were fabricated by two photon laser polymerization using a photosensitive resin. NPCs were grown for different periods inside the Nichoid (1x104 cells at plating). Growth curves were performed and cells features were characterized by immunofluorescence, Western Blot, and Real Time PCR analysis. Parkinsonism was induced by the intraperitoneal administration of MPTP in C57/black mice by using an acute protocol. NPCs were transplanted in a murine experimental model of PD after a 7 days’ growth inside the Nichoid. RESULTS: NPCs grown inside the Nichoid create a 3D carpet expanding inside the scaffold. 7 days after plating, cells grown inside the Nichoid show a significantly higher proliferation than in normal floating culture conditions. NPCs expanded inside the Nichoid maintain their biological features and show an increase in stemness potential, as demonstrated by immunofluorescence, Real Time-PCR, Western blot and methylation assay. The therapeutic effect and safety of Nichoid-grown NPCs was evaluated by their intrastriatal infusion (7x104 cells) in PD affected mice. Behavioral performances were evaluated with two different tests showing that Nichoid-grown NPCs promoted the recovery of PD symptoms and favor the expression of tyrosine hydroxylase in the pathology affected brain areas. CONCLUSIONS: Stem cells showed an increase in stemness potential when grown inside the Nichoid, showing great promise and strong application in the field of regenerative medicine applied to neurodegenerative disease.