Postdoctoral Research Fellow The Florey Institute Parkville, Victoria, Australia
Abstract: Differentiation of human pluripotent stem cells into defined cellular populations have vast research, industry and clinical applications ranging from modelling development and disease through to advancing drug development and cell-based therapies. Necessary for their use is the establishment of defined protocols that emerge from a culmination of developmental knowledge, yet these protocols rarely perform systematic assessment of all the media components and their resultant necessity, potential detriment and not to mention cost implications, particularly during maturation, post regional specification. Assessing 16 combinatorial conditions, here we examined the 4 trophic proteins commonly included in neuronal maturation media - Brain Derived Neurotrophic Factor (BDNF), Glial-cell derived neurotrophic factor (GDNF), dibutyryl cyclic Adenosine Monophosphate (dcAMP) and transforming growth factor- ß3 (TGF-ß3). Cultures were analysed for survival, retained specification and functionality as well as the impact of trophic factor ablation on subsequent graft survival and function in a rat model of Parkinson’s disease (PD). Omission of growth factors had no impact on cell survival or dopamine neuron proportions, with cells able to regulate expression of pro-survival transgene PITX3 in response to altered culture conditions. Furthermore, transplantation of neural progenitors cultured in the absence of these trophic cue had no detrimental impact on graft outcomes in PD rats. Parallel assessment in maturing cortical and motor neuron differentiations similarly suggest that these trophic cues are dispensable within cultures, with this knowledge providing a significant cost benefit for human stem cell-based research including clinical and industry translation.
