CNTF and Parkinson disease: Neurotrophic growth factors like NGF, BDNF, ciliary neurotrophic factor (CNTF) and GDNF have been found to be increased after NPC transplantation and are likely responsible for the prevention of neuronal programmed cell death and glial scar formation in both primary and secondary neurodegenerative disorders – such as SCI, ischaemic stroke, HD, PD, and demyelinating disorders[6,90–95].