Being the second most prevalent neurodegenerative disorder in the world, it is alarming that for the last six decades, therapy for Parkinson's disease (PD) has consisted mainly of symptomatic treatment which does not interrupt or slow down the progression of the disease. However, in spite of the lack of clinical changes, research has been far from stagnant. Neurotrophic factors - proteins which play critical roles in nervous system development and cell survival - have shown promising results for the treatment of neurodegenerative disorders including PD. Members of the GDNF family of growth factors have shown promising results in promoting cell survival in models of PD. One of the many research models is the use of the SHSY-5Y human neuroblastoma cell line that can be differentiated into stereotypical dopaminergic neurone type through treatment with retinoic acid or 12-tetradecanoyl-13-acetyl-beta-phorbol (TPA). Subsequently, PD neurodegeneration can be mimicked by chemical insult with 6-hydroxidopamine (6-OHDA) then allowing assays on neuroprotection and neurorescue. Using this model, the objectives of this work are to evaluate the best conditions for differentiation, neuroprotection and neurorescue using GDNF, GDF-5, Neurturin CDNF and MANF. Once each growth factor is assessed individually, we will test combinations of growth factors providing optimal SHSY-5Y cell line neuroprotection.